ACEEE_Emerging Indust EE Technologies_detail_Oct 2000

EMERGING ENERGY-EFFICIENT INDUSTRIAL TECHNOLOGIESAPPENDIX

Table of ContentsIntroduction....................................................................................................................... 3Technologies ...................................................................................................................... 3

Twin chamber pulp lifter (alumina production) ......................................................................................... 3Pot lining additive (aluminum)................................................................................................................... 3Improve casting furnace technology (aluminum)....................................................................................... 4Improvements to the aluminum grain refinement process (aluminum) ...................................................... 4Innovative Tunnel kiln (bricks and tiles).................................................................................................... 4Advanced coating processes (car manufacture).......................................................................................... 5Cogen--exhaust gas drying of blast furnace slag for blended cements (cement)........................................ 5New refractory materials (cement) ............................................................................................................. 5Fluidized bed kiln (cement)........................................................................................................................ 6Mineral polymers (cement) ........................................................................................................................ 6Heat recovery for cogeneration (cement) ................................................................................................... 6Advanced communition (cement) .............................................................................................................. 6High efficiency roller mills-raw material (cement) .................................................................................... 7Ammonia – adiabatic pre-reformer (chemicals) ......................................................................................... 7Ammonia process control technology (chemicals)..................................................................................... 7Ammonia - membrane reactor for steam reforming (chemicals)................................................................ 8Ammonia - membrane reactor for selective ammonia removal (chemicals) .............................................. 8Advanced chlorine cells (chemicals) .......................................................................................................... 8Corn fiber fractionation (chemicals)........................................................................................................... 9Selective cracking – ethylene (chemicals).................................................................................................. 9Oxy-burners (chemicals) ............................................................................................................................ 9Direct production of silicones from sand (chemicals) .............................................................................. 10Chlorate cathodes for ClO2 production (chemicals) ................................................................................. 10Catalytic autothermal oxydehydrogenization (CAO) (chemicals)............................................................ 10Advanced reactor design – methanol (chemicals) .................................................................................... 11Electrodeionization (chemicals) ............................................................................................................... 11Advanced recovery systems – fractionation (chemicals).......................................................................... 11Melt crystallization - benzene (chemicals) .............................................................................................. 11Alkane functionalization catalysts (chemicals) ........................................................................................ 12Solvent recovery using liquid nitrogen (chemicals) ................................................................................. 12Dividing wall column – olefins production (chemicals)........................................................................... 12Oxy-fuel burners (metal casting) (cross-cutting)...................................................................................... 13Tube feeder (cross-cutting)....................................................................................................................... 13Meta-lax stress relief method (cross-cutting) ........................................................................................... 13Energy management systems (cross-cutting) ........................................................................................... 14Clean energy systems (cross-cutting) ....................................................................................................... 14Heat pumps (cross-cutting)....................................................................................................................... 14Advanced electrogalvinization (cross-cutting) ......................................................................................... 15Written pole motor (cross-cutting) ........................................................................................................... 15Copper rotor motor (cross-cutting)........................................................................................................... 15Electronically commutated permanent magnet motor (cross-cutting) ...................................................... 15Efficient transformers (cross-cutting)....................................................................................................... 16General heat recovery (cross-cutting)....................................................................................................... 16Molten metal filtering (cross-cutting)....................................................................................................... 17GFX drainwater heat recovery (cross-cutting) ......................................................................................... 17High-efficiency welding (cross-cutting)................................................................................................... 17Low friction working fluids (cross-cutting) ............................................................................................. 17Recuperative regenerative boilers (cross-cutting) .................................................................................... 18Advanced polysilicon production (electronics) ........................................................................................ 18

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Heat recovery food - high temperature (food processing) ........................................................................ 18Freeze concentration (food processing) .................................................................................................... 184 or more effect evaporator for cooling (food processing) ....................................................................... 19Heat pump dryer (food processing) .......................................................................................................... 19Condi-cyclone dryers (food processing).................................................................................................. 19Controlled atmosphere packaging (food) ................................................................................................. 20Efficient cooling systems (food)............................................................................................................... 20Process control-glass tanks (glass) ........................................................................................................... 20New glass melting technologies (glass).................................................................................................... 21Efficient burners for glass furnaces (glass)............................................................................................... 21Electric forehearth with indirect cooling (glass)....................................................................................... 21Ion-exchange system – float glass (glass)................................................................................................. 21High levels of pulverized coal injection (iron and steel) .......................................................................... 22Advanced coke oven gas co-generation technology (iron and steel) ........................................................ 22On-site pickling HCl regeneration (iron and steel)................................................................................... 23Intelligent inductive processing (iron and steel) ....................................................................................... 23Improved EAF refractories (iron and steel) .............................................................................................. 23Coke dry quenching (iron and steel)......................................................................................................... 24Non-recovery coke ovens (iron and steel) ................................................................................................ 24Waste oxides recycling in steelmaking furnaces (iron and steel) ............................................................. 24Heat recovery in sinter plants (iron and steel) .......................................................................................... 25Scrap pre-heating electric arc furnace (EAF) technologies (iron and steel) ............................................. 25Recuperative burners in the rolling mill (iron and steel) .......................................................................... 26Direct steel strapping production (iron and steel)..................................................................................... 26Improved drying systems (lumber and wood products............................................................................. 27Heat recovery turbine (metalcasting)........................................................................................................ 27Furnace process modeling and control (metal casting)............................................................................. 27Unconventional yield improvement methods (metal casting) .................................................................. 28Simulation programs for process management (metal casting) ................................................................ 28New metal heating approaches (metal casting) ........................................................................................ 28Die casting copper motor rotors (metal casting)....................................................................................... 29Ceramic filters (mining) ........................................................................................................................... 29Vibration fluidized bed separation (mining)............................................................................................. 29Ramex tuneller (mining)........................................................................................................................... 30Ammonia absorption refrigeration unit (petroleum refining) ................................................................... 30Hydrogen purification improvements (petroleum refining)...................................................................... 30Selective oxidation of benzene to phenol (petroleum refining) ................................................................ 30Liquid membranes in refining (petroleum refining) ................................................................................. 31Low profile FCC (petroleum refining) ..................................................................................................... 31Fluidized bed reactor for plastics recovery (plastics) ............................................................................... 32Heat recovery in plastics (plastics) ........................................................................................................... 32Water as cooling refrigerant (plastics)...................................................................................................... 32Tunnel kiln (plastics) ................................................................................................................................ 33Heat recovery – printing (printing).......................................................................................................... 33Flotation deinking for stickies removal (pulp and paper) ......................................................................... 33Bacterial reduction of sulfur to sulfide in kraft mills (pulp and paper)..................................................... 34Press drying (pulp and paper) ................................................................................................................... 34Biopulping (pulp and paper) ..................................................................................................................... 34Fluidized bed combustion for sludge/bark/wood fiber waste (pulp and paper) ........................................ 35Air/Steam impingement drying (pulp and paper) ..................................................................................... 35Freeze concentration mill effluent (pulp and paper)................................................................................. 35Fiber loading equipment for PCC (pulp and paper).................................................................................. 36Thermodyne pulp dryer (pulp and paper) ................................................................................................. 36Super pressurized groundwood pulping (pulp and paper) ........................................................................ 36Direct drying cylinder firing (pulp and paper).......................................................................................... 36Molten metal paper dryer (pulp and paper) .............................................................................................. 37

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Multi-port drying cylinder (pulp and paper)............................................................................................. 37Fluidized bed heat exchanger (pulp and paper) ........................................................................................ 37New refractory materials-lime kiln (pulp and paper) ............................................................................... 38Supercritical extraction and protein separation (textile) ........................................................................... 38Suction slot dewatering (textile)............................................................................................................... 38Direct contact water heating (textile) ....................................................................................................... 39Textile heat recovery (textile)................................................................................................................... 39Dyeing vacuum system (textile) ............................................................................................................... 39Automated dyebath reuse technology (textile) ......................................................................................... 39Membrane technology – textiles (textile) ................................................................................................. 39

IntroductionIn the main body of this report (ACEEE Report #IE003), Lawrence Berkeley National Laboratory and theAmerican Council for an Energy-Efficient Economy identified 173 emerging energy-efficient industrialtechnologies. Because of resource constraints, only the 54 highest scoring technologies were profiled in detailin the main body of the report. The selection process used was by no means perfect, with those selected orrejected based upon the researchers’ judgment and sponsors’ interests. Many technologies not profiled offersignificant opportunities, particularly to some states and regions in which the applicable industries dominate.

To capture the information collected in the initial research phase of the study, the authors have prepared thisappendix. A brief profile is provided for each technology that was not selected for detailed profiling in thesecond phase of the study. Included with each profile are the key reference sources identified in the initialscreening. While these profiles lack the detail of those provided in the main body of the report, the authorshope that the information included can provide a starting point for future efforts investigating thesetechnologies.

Technologies

Twin chamber pulp lifter (alumina production)Alumina, the precursor used in the production of aluminum, is extracted from bauxite ore using the Bayerprocess. In the first stage of this process, crude bauxite ore is dried, crushed and blended with recycled plantliquor (containing dissolved sodium carbonate and sodium hydroxide). This is formed into a slurry that is thenfurther processed (Margolis, 1997). The flow of the grinding mills is essentially controlled by the efficiency ofthe grate and pulp lifters. One manufacturer, JK Tech, developed a twin chamber pulp lifter that prevents thepulp from flowing backward and thereby impeding throughput. Alcoa installed the JKJetLift pulp lifter in oneof their semi-autogenous grinding mills in Western Australia in 1999. Results from this installation indicated anincrease in throughput by 15% compared to existing mill configurations resulting in a decrease in electricity useof 0.7 kWh/ton (Cameron, 2000). U.S. alumina capacity has been stable at 5 million tons (USGS, 2000).Potential energy savings for this application are limited (less than 1 TBtu).

Margolis, N. 1997. Energy and Environmental Profile of the U.S. Aluminum Industry. DOE97-IOFA12.Washington, DC: U.S. Department of Energy, Office of Industrial Technologies.

Cameron, Peter. 2000. “Improved slurry transport in AG and SAG mills with JKJetLift,” Personalcommunication and informational materials provided by Alcoa Wagerup.

United States Geological Survey (USGS), 2000. Mineral Commodity Summaries—Bauxite and Alumina.(http://minerals.usgs.gov/minerals/pubs/commodity/bauxite/)

Pot lining additive (aluminum)Primary aluminum production involves the electrolytic reduction of alumina into alumina (Hall-Heroultsmelting process). This is accomplished in a series of cells or “pots” that are connected in long lines. In eachcell the refractory material is overlaid with a carbon lining and a carbon cathode. Preliminary research byEMEC Consultants indicates that cell operation, cathode performance and options for the disposal of spent potlining will be improved by additives to the pot lining (OIT, 1999). An R&D project funded by the U.S.Department of Energy’s Office of Industrial Technology focused on using the addition of boron oxide to pot

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lining as a way to suppress cyanide formation and potential reducing ohmic cell resistance and sludge formation(OIT, 1999). Potential projected energy savings in 2010 based on OIT calculations are 2 TBtu with cost savingsof $23 million annually. The technology is expected to yield savings in both O&M and reduced disposal costsfor spent pot liners. The product is still pre-commercial, with a full test in a working cell planned for 2002 (OIT,1999).

Office of Industrial Technology, U.S. Department of Energy, 1999. “Boron Oxide Added to Pot lining willIncrease Energy Efficiency and Operations in Primary Aluminum Production,” project fact sheet.(http://www.oit.doe.gov/factsheets/aluminum/pdfs/potliningadd.pdf)

Improve casting furnace technology (aluminum)The production of secondary aluminum involves the smelting of pre-treated scrap in melting furnaces.Depending on the quality of the scrap various furnace types are used. Several opportunities exist to furtherimprove melting furnace efficiency and reduce energy consumption, including improved agitation in the bath,the use of alternative fluxes, and improved furnace designs (F.T. Gerson Ltd, 1993). In one U.S. Department ofEnergy project, Air Products and Chemicals in collaboration with Argonne National Laboratory, WabashAlloys, and Brigham Young University are developing a low-NOx combustion system combined with an on siteoxygen generation system (OIT, 1999). The use of enriched air in furnace combustion is expected to improveheat transfer to the melt as well as reduce emissions. The goal of this particular project is to increase meltingproductivity by 30%. The system is currently in the demonstration phase and is expected to reach commercialviability in the near future (OIT, 1999). Potential savings in 2015 could reach 6-8 TBtu.

F.T. Gerson Ltd., 1993. Processes, Equipment and Techniques for the Energy Efficient Recycling of Aluminum,prepared for Efficiency and Alternative energy technology Branch, Canada Centre for Mineral andEnergy Technology (CANMET).

Office of Industrial Technology, U.S. Department of Energy, 1999. “High-efficiency, high-capacity, Lox-NOxAluminum Melting Using Oxygen-Enhanced Combustion,” project fact sheet.(http://www.oit.doe.gov/factsheets/aluminum/pdfs/lownox.pdf)

Improvements to the aluminum grain refinement process (aluminum)Almost all aluminum cast in the U.S. is grain refined, which involves the reaction of salts with aluminum. Anew method for grain refining aluminum castings, the fy-Gem process offers significant cost, energy andenvironmental benefits. The development of this process by several project partners (Alcoa, GKS Engineering,GRAS Inc, JDC Inc., Littlestown Hardware and Foundry, Touchstone Laboratory) is being supported by theOffice of Industrial Technology, U.S. Department of Energy. DOE estimated that by 2010, potential energysavings from the use of this process could reach 2 TBtu as well as the elimination of several million pounds ofspent salt.

Office of Industrial Technology, U.S. Department of Energy, 1999. “New Effective Method will ProduceCleaner, Higher Quality Aluminum Castings,” project fact sheet.(http://www.oit.doe.gov/factsheets/aluminum/pdfs/grainref.pdf)

Innovative Tunnel kiln (bricks and tiles)Several new designs that reduce energy consumption in kilns used for brick and tile manufacture have becomecommercialized. Conventional kilns are normally constructed with a fire-proof inner wall, insulation, a brickouter wall and a concrete floor. The walls of the kiln are air-cooled which adds to air leakage into the kilnthereby reducing efficiency. The tunnel kiln design reduces air leakage in the heating zone as a new method ofwater-cooling rather than air-cooling is used for the kiln carts. Product passage through the kiln is also reduced.Energy savings in tunnel kilns are significant. Based on case studies reported in the Netherlands, the new kiln isexpected to use 1,100-1,900 ft3/ton finished product of gas (1.0-1.7 MBtu/ton) consumption and 85 kWh/shortton electricity (CADDET, 1993; CADDET, 1994). This represents energy savings of 15-50% over conventionalprocesses. A U.S. tunnel kiln that uses ceramic fiber insulation and a lower profile stack was able to reduce kilnpreheat time by over 20 hours and also reduce energy consumption by 50% (OIT, 1997). Investment costs areestimated to be 10-20% higher than traditional kilns with a simple payback (based on Dutch gas prices) of 4-6years.

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(CADDET) Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1994. “Energysaving production unit for roof tiles,” technical brochure.

———, 1994. “Efficient tunnel kiln for baking roof tiles,” technical brochure.Office of Industrial Technology, U.S. Department of Energy, 1997. “Brick Kiln Using Low Thermal Mass

Technology,” NICE3 project fact sheet (http://www.oit.doe.gov/nice3/projects/fctshts/brick.shtml).

Advanced coating processes (car manufacture)While auto painting was traditionally dried using gas ovens, there has been a shift to the use of low VOCcoatings with the use of infrared curing technologies. One case study noted the installation of an infrared oveninstalled in 1991 at the Peugeot Talbot Motor Co. The new stoving system resulted in 85% energy cost savingsin the drying section of the plant as well as a significant reduction in labor cost since the technology is computerbased. These systems are increasingly becoming standard because of the competing priorities for maintaining ahigh quality finish on autos but reducing emissions. Surface quality considerations do limit the applicability ofsome IR cured coatings. Another potential trend is molded-in color where the final surface is part of a moldedplastic product. Currently, this is used for some textured body parts (e.g., bumpers) but again surface quality isnot acceptable for smooth body panels, like those used on Saturns which are still painted. A number of autosuppliers are currently working on improved surface quality in molded panels. If this can be achieved, it islikely to be adopted more broadly by manufacturers because of the reduced cost, time savings from eliminationof paint step, and durability benefits. Due to limited data on energy consumption in auto assembly and existingmarket penetration we do not estimate potential savings in 2015.

(CADDET) Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1992“Computerized infra-red stoving oven for use in car manufacture.”

Cogen--exhaust gas drying of blast furnace slag for blended cements (cement)Clinker production is the most energy intensive step in U.S. cement production accounting for over 90% ofprimary energy use (336 TBtu). Clinker is produced in large kiln systems that evaporate free water in the rawmaterials, calcine the carbonate constituents, and form Portland cement minerals (Martin et al. 1999). Typicalfuel use for the clinker kiln is ranges from 3.6-5.1 MBtu/ton clinker. Blast furnace slag has been demonstratedto be an effective clinker substitute in cement, and several European countries have added up to 30-40% blastfurnace slag into the final cement mixture (PCA, 1997). One cement plant in the Netherlands installed a systemin which a gas turbine was used to dry granulated blast furnace slag, resulting in both reduced cost forelectricity production and effective kiln energy savings for the slag substitution. We assume a fuel savingspotential of 1.2 MBtu/ton which accounts for both the kiln fuel savings and the additional fuel requirements todry the slags. Electricity production is estimated at 63 kWh/ton slag. Incremental investment costs are $0.7/tonfor new storage and grinding capacity and $750/kW for the gas turbine system (Alsip, 2000). We estimatepotential savings of 5-8 TBtu by 2015 based on the displacement of 3-4 million tons of clinker.

Alsip, J. 2000. “Combined Heat and Power Capital Costs,” presented at International Symposium CombinedHeat and Power, Energy Solutions for the 21st Century. Feb. 1-2.

Martin, N., E. Worrell, and L. K. Price., 1999.Energy Efficiency and Carbon Dioxide Emissions ReductionOpportunities in the U.S. Cement Industry. LBNL-44182.

Portland Cement Association, 1997. Blended Cement Potential Study. Skokie, IL: Portland Cement Association.

New refractory materials (cement)Clinker production is the most energy intensive step in U.S. cement production accounting for over 90% ofprimary energy use (336 TBtu). Clinker is produced in large kiln systems that evaporate free water in the rawmaterials, calcine the carbonate constituents, and form Portland cement minerals (Martin et al. 1999). There canbe considerable heat losses through the shell of the kiln, especially in the burning zone. The use of betterinsulating refractories can reduce heat losses (Venkateswaran and Lowitt, 1988). A U.S. Department of Energy,OIT, project identified a potential savings of 5% of the heat load with the use of a new high temperatureceramic refractory. O&M costs would also be reduced since the refractory would last longer than itsconventional counterparts (OIT, 1999). We assume the improved materials such as Lytherm can reduce fuelconsumption by 0.15 GJ/t with estimated installation costs of $0.25/tonne clinker. We estimate potential energysavings of 7 TBtu in 2015 based on application to 50% of kiln systems.

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Energy Information Administration, U.S. Department of Energy, 1997. Manufacturing Energy ConsumptionSurvey, 1994. EIA: Washington, DC.


Office of Industrial Technology, U.S. Department of Energy, 1999. “Monolithic Refractory Material” projectfact sheet (http://www.oit.doe.gov/factsheets/inventions/pdfs/monolithic.pdf)

Venkateswaran, S.R. and H.E. Lowitt, 1988.The U.S. Cement Industry, an Energy Perspective, U..S.Department of Energy, Washington, DC.

Fluidized bed kiln (cement)Clinker production is the most energy intensive step in U.S. cement production accounting for over 90% ofprimary energy use (336 TBtu) (Martin et al. 2000). The fluidized bed kiln (FBK) is a new concept for clinkerproduction. In the FBK, the rotary kiln is replaced by a stationary kiln, in which the raw materials are calcinedin a fluidized bed (Martin et al. 1999). An overflow at the top of the reactor regulates the transfer of clinker tothe cooling zone. This system can yield lower capital costs (since it is more compact), lower operatingtemperatures and therefore reduced NOx emissions, and a broader choice in fuel types. Expected energyconsumption is 10-15% lower than conventional processes (van der Vlueten, 1994). Early developments of thistechnology have not been successful, although a U.S. manufacturer, Fuller, was in the lead on technologydevelopment. Further research, development, and demonstration will be needed before this technology canbecome commercially viable. We conservatively estimate potential energy savings of 12 TBtu in 2015, basedon application of FBK to 5% of clinker production.


van der Vlueten, F.P., 1994. “Cement in Development: Energy and Environment,” Netherlands EnergyResearch Foundation, Petten, the Netherlands.

Mineral polymers (cement)Clinker production is the most energy intensive step in U.S. cement production accounting for over 90% ofprimary energy use (336 TBtu) (Martin et al. 2000). Calcining limestone (calcium carbonate) produces clinker.The reaction releases carbon dioxide into the atmosphere leaving calcium silicates as binding agents. Mineralpolymers can be made from inorganic alumino-silicate compounds instead of clinker. They can be produced byblending three elements: calcined alumino-silicates (from clay), alkali-disilicates, and granulated blast furnaceslag or fly ash (Martin et al. 1999). Research on mineral polymers has been going on in Eastern Europe and theU.S. since the early 1980s and the silica-alumina raw materials can be found on all continents. The calcining ofalumino-silicates occurs at 1400°F (750°C) although no energy consumption data for the whole process havebeen found in the literature (Martin et al. 1999).


Heat recovery for cogeneration (cement)Waste gas discharged from the kiln exist gases, the clinker cooler system, and the kiln pre-heater system allcontain useful energy that can be converted into power. We focus on combined heat and power systems thatinvolve the installation of a waste heat boiler system that operate a steam turbine. (The use of direct gas turbinesystems is also possible.) Although electrical efficiencies are low, electricity savings are estimated at 18kWh/ton clinker. We estimate installation costs of $2-4/ton clinker and operating costs of $0.2-0.3/ton clinker(Martin et al. 1999). This type of technology is particularly applicable to long dry kilns but not to the moreadvanced pre-heater, pre-calciner kiln technology which do not produce enough high grade waste heat to meritthe installation of a CHP system. Estimated national energy savings in 2015 are 5 TBtu based on estimatedlong-dry kiln capacity.


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Advanced communition (cement)In cement manufacture grinding is an important power consumer. Grinding mills consume 27-54 kWh/ton.Much of the energy input (over 95%) with current grinding technologies is dissipated as waste heat(Venkaterswaran and Lowitt, 1988). Some of this heat can be used to dry raw materials either in the preparationof limestone or at the finish grinding stage. In particular, longer-term efficiency improvements can be expectedwhen non-mechanical milling technologies become available such as laser, thermal shock, electric shock orcryogenics. While the theoretical energy savings associated with these technologies are large, thesetechnologies are still in the research phase and are not commercially available. We estimate U.S. energy savingspotential of 16 TBtu in 2015, applying savings to a quarter of industry capacity.


Venkateswaran, S.R. and H.E. Lowitt, 1988.The U.S. Cement Industry, an Energy Perspective. U.S. Departmentof Energy, Washington, D.C., USA.

High efficiency roller mills-raw material (cement)In cement manufacture, once the raw materials are mined and quarried, they need to be prepared into a mealthat is then fed into a clinker kiln. In dry processing of raw materials (used in modern plants) the materials areground into a flowable powder in ball mills or in roller mills. High efficiency grinding equipment includes theuse of a vertical or horizontal roller mill, which can save an estimated 6 kWh/ton when compared to an averageball mill. We estimate an investment cost of $4.5/ton raw material based on (Holderbank, 1993) (Martin et al.,1999). Nationally, high-efficiency roller mills are estimated to save 2-5 TBtu in 2015, based on their applicationto at least half the processed raw material.

Holderbank Consulting, 1993.Present and future Energy Use of energy in the Cement and Concrete Industriesin Canada,” CANMET, Ottawa, Ontario, Canada.


Ammonia – adiabatic pre-reformer (chemicals) In the adiabatic pre-reformer incoming natural gas is partially converted to synthesis gas, using highly activecatalysts. The pre-reformer uses excess steam, and hence lowers the steam production in the convection section ofthe reformer furnace. This results in a reduction of the primary reformer duty and hence a reduction in gasconsumption. The technology can only be implemented in older plants with an excess steam production. The systemis developed by Haldor-Topsoe, and has been installed in several plants around the world. One of the first plants wasan ammonia plant from 1968 by Kemira in Rozenburg, The Netherlands installed a system in 1991. The investmentswere equal to about 5$/ton ammonia annual production capacity (10 Dfl/tonne) (CADDET, 1991), with a simplepayback period of 1.2 years under Dutch conditions. The energy savings are approximately 4% of the initial energyconsumption of the plant, or 1.4 MBtu/ton (HHV) (Worrell and Blok, 1994). It is difficult to estimate the share ofammonia production capacity in the US to which the technology could be applied, as we have limited age data ofthe ammonia plants (Worrell et al., 2000). We assume that it can potentially be applied to 25% of U.S. capacity by2015, saving approximately 5.6 TBtu.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1991. “Pre-Reformer and Convection Section,” (DEMO 21), Project NL.90.049, IEA-CADDET, Sittard, TheNetherlands.

Worrell, E. and K. Blok, 1994. “Energy Savings in the Nitrogen Fertilizer Industry in The Netherlands,” Energy2 19 pp.195-209.

Worrell, E., D. Phylipsen, D, Einstein, and N. Martin, 2000. “Energy Use and Energy Intensity of the U.S.Chemical Industry,” Berkeley, CA: Lawrence Berkeley National Laboratory (LBNL-44314).

Ammonia process control technology (chemicals)Every ammonia plant uses some kind of process control systems. In common process control systems energyuse varies more widely, e.g., within a range of ±3-5%. Advanced control systems use automated sampling anddata analysis to optimize process control. The optimization process is always a process with multipleobjectives, but as energy is the feedstock in the ammonia process, energy efficiency is always improved with

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advanced improved process control systems. Various manufacturers are developing advanced control systems,such as M.W. Kellogg (CADDET, 1993) and GE (Lin et al., 1998) in the U.S. Energy savings will depend onthe operation of the plant. Typically savings of 0.6 MBtu/ton of ammonia can be achieved, although largersavings have been achieved, e.g., 1.5 MBtu/ton at Agrium Nitrogen Operations (TX) (Berkowitz, 1997). Weestimate typical savings at 1.6% (CADDET, 1993; Lin et al., 1998). Assuming use in 50% in ammonia plantsby 2015, the technology could result in natural gas savings of 4.9 TBtu. Average payback period may varybetween six months and 2.5 years (CADDET, 1993; Berkowitz and Poe, 1997).

Berkowitz, P.N., 1997. “Optimization of an Ammonia Plant from Advanced Process Control,” PI Users’Conference, San Francisco, CA, April 6-9, 1997.

Berkowitz, P.N. and W. Poe, 1997. “Improved Ammonia Plant Control from Integrated Information Systems,”OSI Process Monitoring Seminar, Houston, November 20, 1997.

CADDET, 1993. “An Optimiser for an Ammonia Factory,” (Demo 29), Project 92.017, IA-CADDET: Sittard,The Netherlands.

Lin, R., R. de Boer and W. Poe, 1998. “The Application of Model Based Predictive Control for AmmoniaPlants,” GE Continental Controls, Inc., Houston, TX.

Ammonia - membrane reactor for steam reforming (chemicals)The relative gas pressures of the reactants and products limit the conversion efficiency of chemical reactions inthe gas phase. Pushing the chemical equilibrium towards a higher conversion rate for hydrogen production canbe achieved by reducing the reaction temperature (by using highly active catalysts), or by removing hydrogenfrom the reactor. Several membranes are being developed that can be used in a membrane reformer reactor, e.g.,dense and porous membranes. The type of membrane affects the reactor design. Strøm et al. (1997) analyzed thepotential energy use of a membrane reactor, and found that it may vary between 26 and 29 MBtu/ton (HHV),depending on the design. De Beer (1998) estimated the net savings of a membrane reactor at 1.5 MBtu/tonammonia. Membranes would be less than 10% of the total capital costs of a new ammonia plant. However, themembranes may need to be replaced several times over the lifetime of the plant, leading to increases in capitalcosts. The design of the membranes and membrane reactor is still under research, and hence potentialapplication of the technology 2015 is limited.

De Beer, J.G., 1998. “Potential for Industrial Energy Efficiency Improvement in the Long Term,” Ph.D. Thesis,Utrecht, The Netherlands: Utrecht University.

Strøm T., T. Pettersen, T. Sundset, and J. Sogge, 1997. “Use of Membrane Reactor in Production of SynthesisGas – Process Options,” Paper presented at ECCE-1, Florence, Italy, May 5-7, 1997.

Ammonia - membrane reactor for selective ammonia removal (chemicals)The production efficiency of the ammonia loop is restricted by the equilibrium of the ammonia synthesisreaction, i.e., the relative gas pressures of the reaction inputs and products. This reaction leads to a conversionrate of approximately 18%. Hydrogen and nitrogen gases need to be recycled through recompression, whichconsumes energy in the large compressors. R&D has taken two directions; the first direction is the developmentof low pressure reactors using new catalysts to reduce the need for compression energy, and the second optionis to selectively remove the ammonia from the reactor vessel, so that thermodynamics drive the reaction to moreammonia production. This removal can be done using membranes or sorbents (De Beer, 1998). Energy savingsare roughly estimated at 1.5 MBtu/ton ammonia, based on a reduction of 50% of the compressor load. In theoryoverall energy savings could be as much as 24 TBtu, assuming full market saturation. R&D is going on atvarious places around the world in developing membranes with a high selectivity, or to new reactor designs forselective removal. However, none of the projects have yet delivered results that are demonstrated at largeindustrial scale. Hence, energy savings by 2015, if any, will be limited.

De Beer, J.G., 1998. “Potential for Industrial Energy Efficiency Improvement in the Long Term,” Ph.D. Thesis,Utrecht, The Netherlands: Utrecht University.

Advanced chlorine cells (chemicals)The production of chlorine is a highly electricity-intensive process requiring between 2780 kWh/ton and 3590kWh/ton depending on the cell type (Worrell et al.,2000; Pletcher and Walsh, 1989). Total energy consumptionfor the U.S. was estimated 200 TBtu in 1994 (Worrell et al., 2000). In the chlorine production process a brine

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solution is converted through electrolysis into chlorine and caustic soda. The most efficient conversion cell onthe market, the membrane cell technology, occupied an 8% market share in the U.S. in 1994 (Worrell et al.,2000). Even membrane cells have opportunities to be further developed. The European Union is currentlysponsoring research to decrease the existing membrane cell energy consumption by an additional 25% byincreasing the current density in the cell from the existing 4 kA/m2 to 5-5.5 kA/m2. Akzo Nobel, one of theleading European companies in the chemical industry, is currently demonstrating a pilot project using a celldeveloped by Krupp Uhde GmbH (EU, 1999). Applying 25% savings to 25% of the industry would yield aprimary energy savings of roughly 40 TBtu in 2015.

European Union, 1999. SESAME project information sheet. Project number IN/0107/98-DEWorrell, E.; Phylipsen, D.; Einstein, D.; Martin, N. 2000. “Energy Use and Energy Intensity of the U.s.

Chemical Industry,” Berkeley, CA: Lawrence Berkeley National Laboratory (LBNL-44314)Pletcher, D. and Walsh, F. 1989. “The Chlor-Alkali Industry,” in Industrial Electrochemistry, 2nd Ed.

Corn fiber fractionation (chemicals)For the industrial chemicals industry, corn fiber fractionation promises to be an energy-saving and cost-savingsource of polyol feedstock. Corn fiber—the outer covering of the corn kernel after the wet milling process—isan inexpensive and abundant renewable feedstock available as a by-product of the corn milling industry. Morethan 10 billion pounds of corn fiber is sold as animal feed at $0.03 to 0.04 per pound, an extremely low-valueuse for the material. Innovative new technology is being developed to cleanly and selectively removehemicellulose from the corn fiber and to subsequently separate and isolate the xylose and arabinose fraction.Hemicellulose makes up 60 to 70 percent of the weight of corn fiber, and xylose and arabinose make up about60 to 70 percent of the weight of the hemicellulose. Catalytic conversion of xylose and arabinose into ethyleneand propylene glycol (polyols) would produce a valuable feedstock with a very large market and a variety ofapplications (4.3 billion per pound of ethylene glycol and 0.8 billion per pound of propylene glycol areproduced each year). The cost of xylose and arabinose would be very competitive—about $0.03 to 0.05 perpound. This technology could potentially lead to a saving of 0.3 TBtu by 2015 (OIT 1999).

Office of Industrial Technology, U.S. Department of Energy, 1999. “Fractionation of Corn Fiber for theProduction of Polyols,” project fact sheet.http://www.oit.doe.gov/factsheets/chemicals/pdfs/cornfiber.pdf

Selective cracking – ethylene (chemicals)Kellogg Brown & Root (KBR), Houston, Texas, announced the release of selective cracking optimum recoveryethylene (SCORE) process. This process is a hybrid; combining the best features from three leading olefintechnologies (M. W. Kellogg, Brown & Root and Exxon Chemical Co.). The heart of the new process focuseson raising the severity of the furnace, thus enabling higher conversions, improved selectivity and greaterproduct yields. For gas cracking applications, increased conversion reduces recycling requirements. This allowssavings through the recovery-section capital costs. (See "HP Innovations".)

M. W. Kellogg, Brown & Root and Exxon Chemical Co. website.http://www.hydrocarbonprocessing.com/archive/archive_99-04/99-04_insight.html

Oxy-burners (chemicals)A waste acid regeneration and recycle plant can be modified to use pure oxygen instead of combustion air. Thetechnology can save up to 16,400 metric tons (3,723 English tons) of oil equivalent per year of natural gas andachieve reduced emissions of sulfur dioxide and nitrogen oxides (CADDET 1992). An example of where oxy-burners can be used is in the process of Spent Acid Recovery. The process of Spent Acid Recovery (SAR) hasthree phases:

1. Preconcentration, where water and light organics are removed from the BPA stream.2. Acid Pyrolysis, where the concentrated BPA stream is burnt to produce sulfur dioxide.3. Acid Regeneration, where the sulfur dioxide is regenerated to sulfuric acid.

During phase two of the process, hot air is normally used in the combustion of spent sulfuric acid. After heatrecovery, cleaning and the removal of water, the sulfur dioxide is converted back to pure sulfuric acid.

http://www.oit.doe.gov/factsheets/chemicals/pdfs/cornfiber.pdf

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Replacing air with oxygen eliminates the need to heat and process large volumes of nitrogen present in air. Thisgives substantial improvements in energy use and furthermore results in a reduction in equipment size. If thistechnology is applied to the production of sulfuric acid, a savings of 0.135 TBtu per year can be expected.

(CADDET) Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1992.“Combustion Air Replaced by Oxygen in an Acid Regeneration Plant,” technical brochure.

Direct production of silicones from sand (chemicals)A new process is proposed for producing silicones from low-cost silicon dioxide (sand, quartz) that will bypassseveral energy-intensive stages and reduce many of the wastes generated by the present technology.Researchers hope to develop a new silicon-carbon bonding reaction that will allow a variety of silicon-carbonlinkages. The new chemistry will in turn permit development of new lower-cost silicone materials that will beuseful to industry and to consumers. The competitive cost of the new products will encourage wider applicationin elastomers, copolymers, flame-retardants, and additives. Silicone-organic copolymers also offer attractivecapabilities for industrial applications if they can be produced cost-effectively. The new process eliminates theelectrochemical conversion of silicon dioxide to elemental silicon. The use of high-risk hazardous reagents andprocesses will also no longer be necessary, leading to a significant reduction in the use of electricity and coal,carbon dioxide emissions, and production of salt and other solid wastes by industry. This technology is still inthe research and development stage, and must overcome several technological barriers before becomingcommercially viable. Direct production of silicones from sand will most likely not enter the marketplace by2015.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Direct Production of Silicones from Sand,”project fact sheet. http://www.oit.doe.gov/factsheets/chemicals/pdfs/silicone.pdf

Chlorate cathodes for ClO2 production (chemicals)There are environmental constraints against the use of molecular chlorine in bleaching operations in the pulpand paper industry, and the industry is turning to chlorine dioxide (ClO2) as an alternative bleaching agent. Themost efficient method for producing ClO2 involves purchasing sodium chlorate (NaClO3) and reducing it tochlorine dioxide through a reaction with hydrochloric acid or sulfur dioxide. It is important to the industry thatthe cost of NaClO3 is kept low to make this process cost-effective. Unfortunately, the increased demand forchlorine dioxide as a bleaching agent has raised the price of its precursor, and the industry must look for otheroptions to produce chlorine dioxide. Electrochemical methods for generating chlorine dioxide directly areexpensive or the processes have other penalties. New electrode technologies are needed to overcome presentlimitations to on-site/on-demand production of ClO2. Investigators at Auburn University believe that a uniquethree-dimensional structure they have developed for the primary cathode will provide U.S. mills with anefficient and cost-effective method for producing ClO2. The cathode is an intermingled network of metal fibersand of activated carbon fibers to which appropriate combinations of catalytic metals have been added. Thecathode technology is revolutionary in that it is made on high-speed, papermaking equipment, and forms astrong, conductive structure.

http://www.oit.doe.gov/factsheets/forest/pdfs/chlorine.pdf Catalytic autothermal oxydehydrogenization (CAO) (chemicals)The production of the chemical ethylene has been ranked as the most energy-intensive process in the chemicalindustry. A new technology, catalytic autothermal oxydehydrogenation (CAO), somewhat similar to oxidativecoupling of methane, could help revolutionize the manufacture of many organic chemicals, including ethylene.Replacing the current steam cracking process with CAO could provide high yields of ethylene and other olefinswith lower energy requirements and waste generation. Unlike the conventional method, CAO is an internallyfired process that does not require a furnace and produces no flue gas. This simplified process produces therequired olefin, along with water and small amounts fuel gas containing methane, hydrogen, and carbonmonoxide. This fuel gas can be used in existing heating applications or reformed to synthesis gas for chemicaland/or liquid fuel synthesis. Because CAO does not leave a coke residue in the reactor, decoking shutdowns,their associated waste streams, and energy expenditures for restarts are all eliminated. These savings furtherincrease operational efficiency and indicate that the application of CAO could yield significant energy savings;

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reductions in greenhouse gases (CO2 and NOx); and cost-savings for operations, capital investments, andretrofits. Estimated energy savings of 11 to 15 trillion Btu per year are possible by 2020 (OIT 1999).

Office of Industrial Technology, U.S. Department of Energy, 1999. “Oxidative Cracking of Hydrocarbons toEthylene,” project fact sheet.

Advanced reactor design – methanol (chemicals)In the state-of-the-art methanol production processes the conversion of synthesis gas to methanol is only 40-50percent. To use the raw material economically recycling is necessary. First, the reactor product is cooled so thatmethanol condenses. Then, the unconverted syngas is recompressed, heated and recycled to the reactor feed. Thisbrings along large investment costs and a large energy consumption. A low energy (and capital requirement)process should be directed at avoiding the equilibrium of the reaction, that is 'taking the product away’. Theprocess with a reactor section with interstage product removal (RSIPR) seems most promising. Methanol isselectively removed in a liquid absorber at interstage reaction zones. Absorption takes place close to the reactiontemperature to avoid heating and cooling of large streams. The process has been tested in a mini-plant. It wasshown that a 97 percent conversion per pass is possible. The efficiency of the process is expected to increase to 80-85 percent (80-85 percent of the raw material is converted to methanol) as compared to 60-65 percent of currentcommercial processes. This measure only affects the energy consumption of the synthesis processes. We assumethat the future methanol plant includes combined reforming and an advanced reactor. The process will be 20percent (15 percent combined reforming, 5 percent synthesis) more energy efficient than the 1990 average.Investment costs are like that of a conventional plant.

http://www.ekinteractive.com/Kellogg/services/technol/methanol/effic.htmhttp://www.hydrocarbonprocessing.com/archive/archive_99-07/99-07_general-dutta.htmDe Beer et al. 1994.

Electrodeionization (chemicals)Electrodeionization, also called “electrochemical ion-exchange,” is an established technology that blends thefeatures of ion-exchange (an adsorption technology) and electrodialysis (a membrane-separation technology).Advantages of electrodeionization over these single technologies include greater energy efficiency, eliminationof chemical regenerants (acids and bases), and elimination of salty waste water streams. Electrodeionization canalso handle very dilute feed streams of low electrical conductivity. Until now, this technology has primarilybeen applied to purifying water for the pharmaceutical, semiconductor, and biotechnology sectors. Thistechnology would expand its application to the chemical industry for economically purifying products,recovering waste, and recycling water. The industry’s process streams and waters are highly complex, andelectrodeionization has the potential to handle such challenges as organic foulants, multivalent ions, and anacidic or basic pH. This technology is estimated to save 5.3 TBtu in 2020 (OIT 1999). The authors believe thatthis claim is a bit optimistic, but possible if widespread adoption of the technology takes place.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Advanced Electrodeionization Technologyfor Product Purification, Waste Recovery, and Water Recycling,” project fact sheet.

Advanced recovery systems – fractionation (chemicals) In olefins processing, the gases that leave the cracking furnace are quickly chilled (quench) and fractionated in theproducts (ethylene, propylene. butadiene, aromatics and fuel gas). Fractionation is done by distillation at very lowtemperature and high pressures. The chilling of the cracking can be made more efficient using advanced recoverysystems (ARS). ARS uses an exchanger in the demethaniser that achieves mass transfer as well as heat transfer.Total plant energy will be reduced by 5 percent relative to conventional designs. Investment costs will reducesignificantly when a new plant is built. In revamp situation the throughput of the fractionation section can beincreased with 40 percent, while compression power per ton of ethylene is reduced by 10-15 percent. Investmentcosts in revamp situation are not known but can be contributed to higher ethylene yield. We assume a 5 percentsaving is possible on the energy demand of olefin production without additional investment costs.

De Beer, et al. 1994.

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Melt crystallization - benzene (chemicals)Although static melt crystallization is not a new process, lower-priced equipment, the quest to eliminate toxic orhighly reactive solvents, and the need to generate high-purity chemicals in small batches is creating renewedinterest in this technology. In this process, solid material is crystallized from a liquid feed without solvents,separated from the liquid, a portion is melted to remove impurities, and the remainder is removed as product.The use of melt crystallization has been driven by a number of factors such as in-creasing purity requirementsfor targeted applications or new products, more stringent environmental laws concerning plant emissions, astrong interest in reducing energy consumption and operating costs, in addition to the simple need for morecapacity. Primary benefits of static melt crystallization include: no moving parts except pumps and valves; theabsence of slurry handling, filtration or centrifugation; and solvent-free operation. Adaptation of theconventional distillation scheme with a melt crystallization unit offers a saving of 27 percent on the energydemand for the production of benzene.

De Beer, et al. 1994.

Alkane functionalization catalysts (chemicals)Despite being the most abundant and least expensive hydrocarbon feedstock available, alkanes (e.g., methane,ethane, and propane) are rarely used as chemical building blocks because few viable methods exist for theirdirect conversion into valuable products. Methanol, for example, is not produced directly by oxidation ofmethane, but by high-temperature, energy-intensive steam reforming and subsequent hydrogenation processeswhich date back to the 1920’s (OIT 1999). A homogeneous catalyst system is under development that willenable direct oxidation of methane to methanol at ambient temperatures, offering considerable reductions inenergy use and waste generation over current processes. The new system will use catalysts that operate inenvironmentally benign media (e.g., water or dense-phase carbon dioxide), and will eliminate the byproductformation of carbon dioxide, which occurs during conventional steam reforming. Another major application ofthe technology would be conversion of methane to methanol at petroleum drilling sites. Methane at these sites isoften flared or re-injected rather than utilized because of prohibitive transportation costs (methane must becompressed for transport). Conversion of these considerable methane reserves (about 3 million tons in 1995[OIT 1999]) would obviate the need for methane flaring and eliminate the associated emissions of carbondioxide, which are considerable. This technology could result in an estimated energy saving of 7 trillion Btuper year by 2020 (OIT 1999).

[OIT] Office of Industrial Technology, U.S. Department of Energy, 1999. “Alkane Functionalization Catalyst,”project fact sheet.

Solvent recovery using liquid nitrogen (chemicals)Large quantities of solvents are used in the manufacture of magnetic recording films, adhesive tapes, and otherpolymeric films. In order to both save resources and meet environmental protection requirements, it is importantto recover these solvents from the dryers and ovens used in the coating processes. The recovery processesdemand efficient measures that are both benign to the environment and low in energy consumption and runningcosts. With the aim of satisfying these criteria, Osaka Sanso Kogyo Ltd. (OSK), in co-operation with Airco inthe USA, has developed the ASRS (Airco Solvent Recovery System). In conventional drying processes, duringthe coating of film or tape tens of thousands of cubic meters of heated air have to be fed into the dryers/ovensevery hour. This must be done to dilute solvent gases in order to maintain their concentrations below 1/4 of theupper safety limits. Large amounts of energy are consumed in heating and circulating this air. In addition, theprocesses involving cooling, absorption, desorption and solvent recovery treatment of such large volumes ofgases also require large amounts of energy. In contrast, the ASRS makes it possible to increase safely theconcentration of solvent gasesin the drying and solvent recovery processes to 20 or 30 percent (CADDET 1996).

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1996. “SolventRecovery Using Liquid Nitrogen,” technical brochure.

Dividing wall column – olefins production (chemicals)Utilization of the dividing wall column technology enables at least two conventional distillation columns to bereplaced by a single dividing wall column. Dividing wall columns exhibit significantly lower capital and energy

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costs than a conventional column system. The principle of the dividing wall column has been recognized forseveral decades now. The implementation of a simple metal sheet in a distillation column results in 2 integratedcolumns, useful for the separation of a 3 component or multi-component mixtures into 3 pure product streamsor fractions. In this way a fully thermally coupled distillation column is achieved, which reduces energyconsumption. Capital savings will also result because of the application of a single shell and a single reboiler-condenser unit. A case study for butane separation showed that 36 percent saving can be achieved and a 30 percentcost reduction. We assume a 40 percent savings is possible on the energy use for fractionation of the olefines whenthis measure is combined with advanced recovery. No additional investment costs are involved with this measure.This measure replaces all previous measures that apply on fractionation. These systems have existed for 50 years,but are rarely used. Reasons for this are lack of experience with this type of unit, and relatively high cost ofretrofitting of a separation unit. http://www.basf.de/en/produkte/chemikalien/catalysts/licence/dividing/http://www.aiche.org/conferences/techprogram/paperdetail.asp?PaperID=617&DSN=spring01De Beer et al. 1994

Oxy-fuel burners (metal casting) (cross-cutting)In many industrial activities air quality regulation drives the demand for high efficiency but low emissions(NOx, CO) in the combustion process. NOx formation is reduced by reducing the amount of nitrogen in contactwith oxygen at high flame temperatures. Oxy-fuel burners are one technology to both increase efficiency andreduce emissions. These burners are used throughout industry, including the steel and glass sectors. The highvelocities of the gases in the burner ensure that the fuel is completely combusted at a lower temperature zone ofthe flame. For the metal casting industry, one case study discussed the installation of an oxy-fuel meltingfurnace in an iron foundry. The furnace achieved a 30% reduction in energy use as well as a 20% improvementin operational costs with lower initial investment costs than a conventional electric furnace (CADDET, 1995).There are several manufacturers of oxy-fuel burners for the steel industry, including American Combustion,Praxair, and Bricmont. Estimates of cost for the burner installation in the steel industry were $2.5/t capacity,and we would assume slightly higher costs for the metal casting sector.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1995. “Arotating, gas fired oxy-fuel furnace in an iron foundry,” technical brochure 204.

Tube feeder (cross-cutting)Many industrial sectors, such as cement, pulp and paper, food processing and others require the handling andtransport of bulk materials. One particular technology, a tubefeeder was designed for continuous discharge ofbulk solids from silos, hoppers, and pile storage. This technology is basically a screw conveyor working inside arotating tube with slots. As the tube rotates, the bulk material is drawn in uniformly through the slots while aninside screw rotates in the opposite direction thereby allowing the material to be conveyed along the tube(CADDET,1990). Because there are few components wear and tear are minimized. Costs for this technology arealso lower than costs for installing a standard parascrew feeder (CADDET, 1990). Compared to a standardscrew reclaimer, the energy consumption of the tubefeeder for moving wood chips was reduced by 75%, withan average consumption of 46 kWh/1000m3. This translates to savings of 0.2 kWh/ton. Overall savings in theUS by 2015 are expected to be small, less than 2 TBtu.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1990.“Tubefeeder – Advances Simplicity of Bulk Material Handling.”

Meta-lax stress relief method (cross-cutting)The Meta-lax process was developed by Bonal Technologies (OIT 1999a) as a solution to the problem ofdistortion and cracking that can occur as a result of sharp temperature drops during metal processing. The mostcommon methods of relieving thermal stress involve slowing the cooling process down. This is an energy-intensive process in which fuel must be consumed while process temperatures are maintained. Meta-lax, shortfor “metal relaxation,” process relieves thermal stress by using sub-harmonic vibrations to prevent the damageassociated with thermal stress. This process is a proven substitute for 80 percent to 90 percent of heat-treatmentstress relieve in metal working applications. Meta-lax can treat a wide variety of work pieces with a versatile,portable unit and yields results much more quickly than conventional stationary heat-treating furnaces. This

http://www.basf.de/en/produkte/chemikalien/catalysts/licence/dividing/

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method of stress relief reduces energy consumption by 98 percent compared with a natural-gas-fired heat-treating furnace (OIT 1999b). This technology may save 180 trillion Btu in the primary metal industry by 2020according to the DOE Office of Industrial Technologies.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Meta-lax Stress Relief Process SavesEnergy,” project fact sheet.

Office of Industrial Technology, U.S. Department of Energy, 1999. Impacts. Office of Industrial Technologies:Summary of Program Results.

Energy management systems (cross-cutting)Controlling energy costs during production is a prominent consideration for managers in all industries.Monitoring and Targeting Setting (CADDET 1995) techniques have been developed to increase energyperformance information transfer from shop floor operators to the top managers by using appropriate reportingformats for various personnel levels. This presentation of performance has provided the information to indicateexceptional energy consumption figures, which may require further investigation. Ivaco Rolling Mills Divisionof Ivaco Inc. installed a predictive "smart" Demand Side Management System (DMS) in its steel plant/rollingmill complex to reduce energy consumption and also to improve the efficiency of existing equipment(CADDET 1992). Two years after initiation, the system resulted in a demand reduction of 9,894 kW andexisting load cost savings in excess of CAD 864,000. Over the same period, productivity increased 8 percent.Quantifying the benefits of energy management systems is difficult, however, based on savings such as thosereported by Ivaco Inc., it could be estimated that U.S. industry can reduce energy consumption byapproximately 4 percent by 2015 for a savings of approximately 1,200 trillion Btu (MECS).

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1992. “EnergyMonitoring and Targeting Setting,” technical brochure.

———, 1995. “DSM Technology Benefits Steel Producer,” technical brochure.

Clean energy systems (cross-cutting)Combust hydrocarbon fuel with oxygen in the presence of water to produce high-temperature, high-pressure gascomposed of steam and CO2. Clean Energy Systems (CES) can sequester CO2producing sellable CO2, oxygen,nitrogen, and argon. Fuel used in the CES system can come from several sources so long as it is composed ofalmost entirely of carbon, hydrogen, and oxygen. The primary requirements for the fuel are that it is a fluid andfree of ash. Hydrocarbons such as methane, alcohols, hydrogen, and carbon monoxide are suitable fuel sources.Oxygen is used to combust the fuel rather than air as in conventional systems thereby eliminating the formationof NOx and the large volume of exhaust gas. The oxygen is obtained from air via a number of processes,including a commercially available air separation plant. The CES gas generator is the key enabling element ofthis advanced power system. The gas generator embodies numerous rocket-based materials and design features.The end result is a small gas generator that produces steam and CO2 at virtually any desired controlledtemperature and pressure. The CES compares favorably with simple and combined cycle gas turbines.Depending on size, the CES can range from approximately 45-67 percent fuel conversion efficiency (notincluding losses in the air separation plant) (CES 2000).

Clean Energy Systems, Inc. Brochure. Sacramento, California.

Heat pumps (cross-cutting)Increasingly, heat transformers are offering practical solutions to industry’s high-energy costs andenvironmental problems. By taking waste heat from an industrial process and increasing its temperature, theyproduce useful low-cost energy, and considerably reduce emissions. The aim of this analysis is to identify thoseindustrial processes in which the use of heat transformers can be economically favorable. The heat transformeroperates on the principle that the temperature at which water vapor condenses (is absorbed) in a salt solution isabove the temperature at which water evaporates, provided both processes are at the same pressure. Absorptionof water vapor releases heat, increasing the temperature of the salt solution. This heat is then used to generatesteam for the production process by circulating the salt solution through special heat exchangers. Thistechnology has been demonstrated in a variety of industries including the chemical (CADDET 1990) and steel(CADDET 1993) industries. Typically, the use of heat pumps is currently limited to relatively low temperatures

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and is mainly recover waste heat for the production of steam. Applications of open cycle heat pumps (up to afew MW) can be found in fully integrated processes, e.g., for the production of styrene and propylene oxide.Energy savings depend on the specific applications and even the local layout of the process, as do the capitalcosts. Energy savings may vary between 10 percent and 15 percent.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1990. “HeatTransformer in the Chemical Industry,” technical brochure.

———, 1993. “Heat Transformer in the Steel Industry,” technical brochure.

Advanced electrogalvinization (cross-cutting)Electrogalvinization accounts for almost 8 percent of the total electricity consumption in the fabricated metalsindustry. This process deposits a corrosion-inhibiting layer of zinc on steel by electrolysis. Electricityconsumption accounts for 15-35 percent of the total production cost in this process (Elliott 1994). Because allthe new equipment used in this process is patented, operation data is not publicly available. Reduced electricityconsumption must be considered with increased capital costs since electrogalvanization equipment is veryexpensive. Processing lines cost $50-150 million with the more expensive equipment generally being moreenergy-efficient. Advanced electrogalvanization processes could lead to streamlined production. Specificenergy savings are unknown.

Elliott, R. N. 1994. Electricity Consumption and the Potential for Electric Energy Savings in theManufacturing Sector. ACEEE. Washington D.C.

Written pole motor (cross-cutting)The written pole (WP) motor is a single phase AC motor that acts like an induction motor during startup, thenacts like a synchronous motor upon reaching full operating speed. Much like a PC hard drive, which recordsdata onto a disk, the WP “writes” the number of poles, and their locations, electronically onto the rotor. Thisallows the WP motor to obtain higher energy efficiency and lower startup inrush current. The lower inrushinherent in the WP design may extend the expected life of the motor by reducing the inrush stresses. WP motorswere originally intended to replace three phase motors that use phase converters because they can operate onsingle phase power systems, particularly in rural applications such as drying fans, conveyors and irrigationpumps. However, in these cases efficiency was not considered to be a significant issue. The primary barriersfacing WP motor technology are its limited market niche, high first cost, and lack of product understanding bythe purchasing public. Potential energy savings could be on the order of 0.75 TWh (Nadel, et al. 1998).

Nadel, S., L. Ranier, M. Shepard, M. Suozzo, and J. Thorne. 1998. Emerging Energy-Saving Technologies andPractices for the Buildings Sector. Washington, D.C.: American Council for an Energy-EfficientEconomy.

Copper rotor motor (cross-cutting)The substitution of copper for aluminum as the rotor core material in random-wound, induction motorsrepresents the most significant opportunity to improve the efficiency of these widely used general-purposemotors. Currently, rotor cores are made from aluminum, because it can be easily cast and machined. Copper, amore energy-efficient choice because of its superior conduction characteristics, is expensive and hasmanufacturability problems. While copper costs significantly more than aluminum, the cost of the rotor corewould not pose an unacceptable barrier for high-end products. However, only a relatively small number ofrotors can be cast using a die made from conventional materials. Since these dies can cost hundreds ofthousands of dollars each, the die-cost makes the production of these rotors uneconomic Designs for using acopper rotor have been developed, and the use of alternative die materials is now the focus of research by theCopper Development Association, Inc., which is working in cooperation with EPRI and several motormanufacturers. Potential savings could approach 5 billion kWh (Nadel, et al. 1998).


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Electronically commutated permanent magnet motor (cross-cutting)Electronically commutated permanent magnet motors (ECPMs) consist of a rotor with multiple permanentmagnets bonded to it and a stator made of electrical windings, creating a varying magnetic field to drive therotor. The stator field is driven electronically using solid state power devices and feedback fromangular-position sensors. This arrangement eliminates rotor resistive losses, brush friction, and maintenanceassociated with conventionally commutated motors. Other advantages are precise speed control, lower operatingtemperature and higher power factor than induction motors. ECPM efficiency cannot match induction motorefficiency for fixed-speed, full-load operation, but has a significant advantage at reduced speeds. Under thesepart-load conditions, common with many motor applications, induction motor efficiency drops significantlywhile ECPM efficiency remains flat. These motors compete with other motor speed control technologies suchas written pole motors and variable frequency adjustable speed drives. ECPMs are available from manymanufacturers in sizes from fractional hp up to 600 hp. Potential savings could approach 5 billion kWh (Nadel,et al. 1998).


Efficient transformers (cross-cutting)All electric power passes through one or more dry-type transformers on its way to service equipment, lighting,and other loads. Transformers experience two types of losses: no-load and load losses. Transformer energylosses are constant at no-load and vary with the square of the load on the transformer. In typical commercial andindustrial applications, transformers are loaded on average at 30 to 35 percent of their rated output. E Sourcereports that transformer losses represent two to six percent of a typical building's electricity use (Nadel, et al.1998). An LBNL steel report (Worrell et al., 1999) found that transformer losses can be as high as 7 percent,and assumed savings of 4 percent due to new UHP transformers. Currently available materials and designs canconsiderably reduce both load and no-load losses. More efficient transformers with attractive payback periodsare estimated to save 40 to 50 percent of the energy lost by a "typical" transformer, which translates into a oneto three percent reduction in electric bills for commercial and industrial customers. Typical paybacks rangefrom 3 to 5 years (Nadel, et al. 1998).

Worrell, E., N. Martin and L. Price, 1999. Energy Efficiency and Carbon Dioxide Emissions ReductionOpportunities in the U.S. Iron and Steel Sector. Berkeley, Calif.: LBNL.


General heat recovery (cross-cutting)Flue-gas cleaning with a condensing scrubber allows waste-heat recovery and reduces pollutants. Flue gascontains a large amount of heat that is left unused in a conventional boiler system. Using a flue-gas scrubber,this heat is absorbed in the scrubber water, cooling down the flue gas, thereby furnishing low-temperature heat.This heat can be used directly, e.g., for preheating tap water and ventilation air or for floor heating. However, ifthe direct use of low-temperature heat is not feasible, a heat pump can be installed on the secondary side of thescrubber heat exchanger, producing high-temperature heat that can be used directly in a district heating plant.Boiler efficiency approaches 100 percent based on the higher heating value of the boiler fuel. The principle of acondensing scrubber involves a liquid being led through hot flue gas in counter-flow, washing out particles(dust) and water-soluble gases. As the hot flue gas meets the cold liquid, the water vapor in the gas condenses.To wash out the acidic gases in the gas flow, Cambi APC AS uses a diluted soda lye as washing water. Thewater is then neutralized, cooled in a heat exchanger, and reused in the scrubber. The products formed, forexample Na2SO4, may be discharged into the sea as they are found there naturally. A high pH and a lowwashing-water temperature in the scrubber enable high pollutant absorption. The materials used in the systemhave been carefully chosen, considering the corrosion problems that may arise due to the saline water.Corrosion-resistant materials such as polypropylene and glass fiber reinforced polyvinyl ester are used in thesystem. Flue-gas waste heat is transferred to the scrubber water as detectable and latent heat (condensationheat). The flue-gas temperature is reduced from approximately 200°C to 10°C. This process produces low-temperature heat, which is further used in a heat pump. The temperature of the water (40°C) is increased to be

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used directly in a district heating plant at KNP. New heat-pump fluids make it possible to supply water attemperatures of approx. 70°C. This technology provides annual savings in oil consumption of more than NOK900,000.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1998. “Flue GasCleaning and Heat Recovery,” technical brochure.

Molten metal filtering (cross-cutting)Casting molten metal presents many opportunities for contamination, often with particles as small as a fewmicrons. This contamination may be slag, dross, or pieces of refractory from the melting crucible. Metal thatcontains impurities will have reduced strength, requiring a heavier section thickness to compensate. Impuritiesalso present serious stress points if they are located on the surface of castings subjected to mechanical forces.The standard ceramic cellular or reticulated foam filters are not readily adaptable to the highly automated diecasting and permanent mold casting operations. This invention circumvents these problems by creating a filtersystem that has a continuous supply of filter material. Before each pour of metal into the shot tube or mold, thefilter material is advanced to present a clean filter area. As the next section of clean filter material is advanced,the impurities that were filtered out can be observed on the exiting used filter.

Office of Industrial Technology, U.S. Department of Energy. 1999. “Filtering Molten Metal,” project fact sheet.

GFX drainwater heat recovery (cross-cutting)Very little of the heat in hot water is actually used; the vast majority of the energy goes down the drain after thewater is used for such tasks as crystal rinsing and drying applications . Economical recovery of the heat forreuse has been a goal of many inventions over the years using various heat exchange and storage devices. TheGFX falling-film heat exchanger uses a vertical five-foot piece of 3" copper drainpipe wrapped with a spiral of1/2" copper water supply pipe. As the drain water from a shower falls down the drain it forms a falling film onthe inside surface of the drain. This results in very high exchange efficiency with the incoming water in the 1/2"line with typical efficiencies on the order of 40 to 75 percent. This technology crosscuts many industrialsectors, but has particular usage in process with relatively hot wastewater streams. The chemical and foodprocessing industries may benefit from the use of this technology. Precise energy savings are unknown.


High-efficiency welding (cross-cutting)Laser assisted arc welding provides greater flexibility in materials and joint geometries while maintainingwelding speed. This process, when applied to steel welding, meets the needs for a new joining technology.Among other things, the benefits of the combined laser and arc welding process would ease the currentrequirement for precise fit-up when laser welding alone. In addition, with the use of filler metals in the arcwelding component of the process, there would be greater flexibility in the choice of materials that are joinedand the process could be easily applied to non-linear joint geometries. It is expected that the Laser-Assisted ArcWelding (LAAW) process would be advantageous in many applications including tailored-blank welding,dissimilar metal welding, and mill coil joining applications. This project is designed to develop and apply theLAAW process for steel welding. The system design would be optimized for steel applications to bridge thewide joint gaps that are currently unacceptable for autogenous laser welding. Process development will focus onthe application to low-carbon and high strength, low alloy steels. This technology offers some energy savings inthat geometries that formerly required a slower welding speed can take advantage of higher speeds. Sourceshave not been able to offer concrete estimates of energy savings.

Office of Industrial Technology, U.S. Department of Energy. 2000. “Development and Application of Laser-assisted Arc Welding to Steel,” project fact sheet.

Low friction working fluids (cross-cutting)A significant energy consumer in many industrial heat transfer processes is the pumping energy required tomove heat-transfer working fluids through heat exchangers and piping. A significant portion of this energy is

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used to overcome the friction in these devices. Pumping energy can be reduced significantly by using low-friction piping and heat exchangers and increasing cross sectional areas. An alternate, novel approach is toreduce the viscosity of the working fluid. Some research has been undertaken on formulating new workingfluids that preserve the attractive heat transfer properties while reducing friction.

Degens, P. (Northwest Energy Efficiency Alliance). 2000. Personal communication to author. April.

Recuperative regenerative boilers (cross-cutting)Within casting furnaces and boilers, a compact bed of heat storing material within each burner accomplishesheat reclamation. Alternate rapid cycling of each burner pair allows short term heat storage and reclamation.This efficient design preheats the combustion air to within 85-95 percent of flue gas temperature. These naturalgas burners use heat reclaimed from the hot flue gases to preheat the combustion air. The objective is to reducenatural gas consumption by 35-50 percent compared with conventional burners, while still maintaining therequired flame temperature. The approach is to preheat the combustion air using energy reclaimed from the hotflue gases. The furnace can produce 20 percent more product using less energy.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1993.“Regenerative type heat recuperation in a retort furnace,” technical brochure.

Advanced polysilicon production (electronics)AKT's polysilicon technology features a multi-step (SiN/SiO2/a-Si) single-chamber deposition process thatprovides the industry's highest quality, hydrogen-controlled polysilicon precursor film at temperatures up to430°C. A separate pre-heat/post-deposition chamber significantly reduces hydrogen in the deposited silicon filmwhile increasing system throughput. The reduced hydrogen content in the polysilicon precursor film enablesrapid conversion of the film into polysilicon with an excimer laser annealing process performed in a separatesystem. AKT's polysilicon systems continue the use of AKT's patented remote plasma source cleaningtechnology, which reduces particles and process contamination to the lowest levels in the industry, anddramatically extend the lifetime of process chamber components and time between wet cleans.

http://www.eurosemi.co.uk/industry_news/news_oct_nov_2000/stories/akt.htm

Heat recovery food - high temperature (food processing)The food processing industry is one of the largest consumers of energy in manufacturing (1,500 TBtu primaryenergy in 1994). There are many opportunities to take advantage of heat recovery, where “excess” heat fromsome production process is utilized in another process step. This can be accomplished by using part of theexhaust gases from one process as inlet gases to another process, or through the use of heat exchange networks.High temperature heat recovery refers to the recovery of high temperature waste heat from combustionprocesses such as steam production or gas combustion in ovens. A CADDET case study of a heat exchangerthat was installed in a bakery for proofing the over found a payback of 1.5-3.5 years (CADDET, 1997). Anothercase study in a coffee company installed a system that cleaned and then recombusted exhaust gases in order tocomply with local environmental requirements, achieving savings of 70%. We assume a 2% savings in industryfuel use or 22 TBtu in 2015.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1997 Heat pipesaves energy in the baking industry

———, 1997 "Energy efficiency and Environmental Benefits for a Coffee Roasting Company,"

Freeze concentration (food processing)Freeze concentration separates mixtures by crystallizing one or more components and has the potential toproduce and almost completely dry product (de Beer et al. 1994). This type of process shows particular promisein the food processing industry for heat sensitive liquid foods, and has been applied to fruit juices, beer, wine,vinegar, milk, and coffee (SCE, 2000). Because the process takes place at low temperatures aroma losses can beavoided. Several freeze concentration systems are in use with the main commercial system developed byGrenco N.V. (Worrell et al., 1997). A study performed by the Electric Power Research Institute on the potentialfor freeze concentration in the milk and whey industry found that the heat demand could almost be fullyeliminated while electricity demand increased by 30% (de Beer et al. 1994). Some of the challenges of this

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technology are its high cost (three to four times higher than evaporation) and the difficulty in separating icefrom solid (Worrell et al., 1997). We assume a potential savings of 15-20 TBtu in 2015 as this technologypenetrates into the dairy industry.

De Beer, J.; K, Blok, M.T. van Wees, and E. Worrell. 1994. Icarus-3. The Potential of Energy efficiencyImprovement in the Netherlands up to 2000 and 2015. Utrecht, The Netherlands: Utrecht University.

Southern California Edison, Business Advisor website. http://www.scebiz.com/electroscc/fprocess/freeze.htmWorrell, E.; J.W. Bode; J. de Beer, 1997. Analyzing Research and Technology Development Strategies – the

Atlas Project. Utrecht, The Netherlands: Utrecht University.

4 or more effect evaporator for cooling (food processing)Evaporation refers to the process of heating liquid to the boiling point to remove water as vapor. This is used inthe dairy industry to produce evaporated milk products. Standard evaporators are two-stage that require 0.3-0.5kg of steam to evaporate 1 kg of water. State of the art technology (6 stage evaporators) require only 0.09 kgsteam per kg water. The operating costs of evaporation are relative to the number of effects and the temperatureat which they operate. The boiling milk creates vapors that can be recompressed for high steam economythrough adding energy to the vapor in the form of a steam jet, (thermo-compression) or by a mechanicalcompressor (mechanical vapour recompression (MVR)) (Goff, 2000). A powdered milk production plant inTokyo installed a quadruple effect evaporator with MVR and saved 75% of the operating costs. Incrementalinvestment that was 20% greater than the standard system (CADDET, 1992). A second Japanese dairy companyinstalled an MVR plant in its whey production facilities realizing a savings of 0.4 kWh/kg steam evaporated(CADDET, 1997). We assume a savings of 10-20 TBtu in 2015 depending on the rate at which evaporators areable to penetrate into the fluid milk products sector.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1992"Quadruple effect milk evaporator uses mechanical vapor recompression"

———, 1997. Learning from Experiences with Industrial Heat Pumps. Analysis Series No. 23Goff, D. 2000. Dairy Science and Technology Web site, University of Guelph. “Evaporation.”

Heat pump dryer (food processing)Heat pumps use waste process heat and deliver this heat at higher temperatures for process use or for spaceheating. Heat pumps can be used for food processing for various purposes, such as drying and other waterremoval methods. One CADDET case study noted the application of heat pump technology to recover wasteheat from the bottle sterilization process in a dairy and used it for space heating. In another demonstrationproject a thermal vapor recompression unit was installed in a distillery to recover heat from condensers andfrom flash steam, and achieved an energy savings of 15% (CADEET, 1997). Another case study notes the useof heat pump dryer technology for drying fruit and vegetables in a Norwegian food processing company thatsaved 50-80% of energy use (CADDET, 1997b). Although energy savings can be significant, the higher firstcost can be a barrier to investment. We estimate a savings of 5 TBtu based on the application of heat pumps tofruit and vegetable drying.

IEA Heat Pump Centre newsletter, 1999 www.heatpumpcentre.org, [CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1997. Learningfrom Experiences with Industrial Heat Pumps. Analysis Series No. 23CADDET Newsletter, No. 4, 1997 "Low temperature drying of food materials using energy efficient heat pumpdryers"

Condi-cyclone dryers (food processing)In a condi-cyclone dryer system the exhaust air of a dryer is expanded and the water vapor is condensed. Thelatent heat of the water vapor is then recovered. This dry heated air is then recycled to the dryer (de Beer et al.,1994). Because of the pressure loss over the cyclone a compressor is required. If electric driven compressorsystems are used, electricity demand increases while steam demand savings are estimated to be 40% (de Beer etal. 1994). This technology is still under development. Stork Product Engineering in the Netherlands firstpatented the technology in 1989, and has been developing a condi-cyclone device for drying gas on behalf ofShell Technology Ventures (Stork, 2000). We estimate a potential savings of 15 TBtu based on the applicationof condi-cyclone systems to the dairy industry.

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De Beer, J.; K, Blok, M.T. van Wees, and e. Worrell. 1994. Icarus-3. The Potential of Energy efficiencyImprovement in the Netherlands up to 2000 and 2015. Utrecht, The Netherlands: Utrecht University.

Stork engineering web site, 2000. (http://www.spe.storkgroup.com/en/projects/08_condi.html)

Controlled atmosphere packaging (food)The concept of Controlled Atmosphere or Modified Atmosphere Packaging (CAP or MAP) is fast emerging asthe leading packaging option for preservation of fresh and processed foods which are required to be stored overlonger periods of time and under diverse storage temperatures and conditions. Via CAP system, the foodproduct is packaged in a High Barrier Film or laminate, following which the atmosphere inside the pack iscontrolled via various gas flushing and vaccumising options. After the pack is sealed or vacuum packed, theHigh Barrier film prevents further transmission of gasses in or out of the pack, thus extending the shelf life andensuring that the product reaches the customer in a fresher condition. CAP films and pouches are based onpolyamide (nylon) and EVOH High Barrier polymers, the contents of which are adjusted to meet the shelf liferequirements of individual products. They are an ideal cost effective replacement to the expensive tin packingand aluminum foil based laminates, plus they offer the added advantage that the packed product can be visuallyinspected by the consumer prior to purchase. Exact energy savings have not yet been determined.

http://www.hitkaripackaging.com/cap.html

Efficient cooling systems (food)The cooling method developed in this technology involves a new technique, in which the products can bebrought directly into contact with the coolant without the risk of bacteriological contamination. This techniquecould be replicated in a number of different foodstuff industries. In comparison to the old situation, where itemsare cooled by contact with air, the new cooler saves about 140,000 kWh/year of electricity. The heat pumpsaves about 235,000 kWh/year. The overall savings are 375,000 kWh per year. This assumes an averagepower generation efficiency of 37 percent. If this technology is adopted by the food industry, an industry thatmakes use of many cooling processes, savings of approximately 6 TBtu can be expected by 2015.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1995. “Efficientcooling system with heat recovery for tofu production,” technical brochure.

Process control-glass tanks (glass)In 1997, the glass industry produced 21 million short tons of glass and used in excess of 250 TBtu of energy.Over 80% of the energy use in the industry is natural gas, primarily applied for glass melting (EIA, 1996).Opportunities to reduce energy use in the glass melt can have a significant impact in reducing overall energyuse in the sector. One particular area is the use of advanced process control. The Office of Industrialtechnologies (U.S. Department of Energy) has been sponsoring research in this area including: 1) thedevelopment of a more comprehensive model of glass melting furnaces (OIT, 1999a; OIT, 1999d), 2) thedevelopment of more robust and sophisticated sensors, including the use of laser technology (OIT, 1999b; OIT,1999e; OIT, 2000a; OIT, 2000b), and the development of dynamic expert system controls (OIT, 1999c). Weestimate that potential savings from the deployment of these technologies could be as high as 20% of fuel use inthe melt. Installation costs will depend on the specific technology being deployed. We estimate energy savingsof 15-20 TBtu in 2015 based on the application of the technology to melting furnaces.

OIT, 1999. “Glass Furnace Simulation Model Will Improve Energy Use And Efficiency While ReducingEmissions” project fact sheet

OIT, 1999b “Robust Sensor Will Improve Product Quality” project fact sheetOIT, 1999c “Automatic Controls Will Optimize The Overall Performance Of The Glass Manufacturing

System”OIT, 1999d “Combustion Space Models Will Allow Cost-Effective Furnace Design And Modification For

Increased Energy Efficiency”OIT, 1999e “In-situ, real-time measurements of melt constituents”OIT, 2000a. “Diagnostics and Control of Natural-gas fired furnaces via flame image analysis”“Diode laser sensor for combustion control”OIT, 2000b “Diode laser sensor for combustion control”

http://www.spe.storkgroup.com/en/projects/08_condi.html

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New glass melting technologies (glass)In 1997, the glass industry produced 21 million short tons of glass and used in excess of 250 TBtu of energy.Over 80% of the energy use in the industry is natural gas, primarily applied for glass melting (EIA, 1996).While melting a ton of glass theoretically requires about 2.2 MBtu of energy, in practice a minimum of twicethis amount of energy input is used due to losses and inefficiencies (OIT, 1997). The U.S. glass industry hasidentified the development of new melting technologies as one of its top technical research priorities (OIT,1997). However, this research is still being undertaken and there are no major technological breakthroughs yetfor the major segments of the industry. For some niche applications there have been some new developmentsincluding a rotary electric glass furnace (not currently being funded) for re-pressing glass (Marino, 2000). Also,in the area of optics manufacture, Toshiba has developed a finished molded lens machine that combinespressing and molding into one step (Marino, 2000).

Marino, A. 2000. Advanced Glass Industries. Personal Communication. OIT, 1997. Glass Technology Roadmap Workshop. Document prepared by Energetics, Inc. Workshop held in

Alexandria, VA on April 24-25th.

Efficient burners for glass furnaces (glass)In 1997, the glass industry produced 21 million short tons of glass and used in excess of 250 TBtu of energy.Over 80% of the energy use in the industry is natural gas, primarily applied for glass melting (EIA, 1996). Oneof the success stories for the U.S. glass industry has been the relatively rapid uptake of oxy-fuel burnertechnology which is now installed in about one-fourth of the glass making capacity in the U.S. (OIT, 2000).While opportunity still exists to further integrate oxy-fuel combustion into the industry, there are alsoopportunities to further improve these combustion systems. For example, some systems generate relatively highNOx emissions. One DOE sponsored research project in conjunction with Combustion Tec and Owens Corningsought to develop a high-luminosity, low NOx oxy-fuel burner system. Laboratory results indicated a 12%improvement in heat transfer efficiency, which translates to a savings of 7 TBtu when applied to 50% of the gasconsumption in the industry (OIT, 1999). Other burner technology research for applications in the glass industryand elsewhere is going on throughout the world, and is part of the U.S. Department of Energy’s crosscuttingresearch vision. We estimate a potential savings of 10-15 TBtu in 2015.

OIT, 1997. “Oxy-fuel firing,” Office of Industrial Technology, Program Impacts Document.OIT, 1999. “High-luminosity, how NOx Burner.” Project fact sheet.

Electric forehearth with indirect cooling (glass)In 1997, the glass industry produced 21 million short tons of glass and used in excess of 250 TBtu of energy.Over 80% of the energy use in the industry is natural gas, primarily applied for glass melting (EIA, 1996).While melting a ton of glass theoretically requires about 2.2 MBtu of energy, in practice a minimum of twicethis amount of energy input is used due to losses and inefficiencies (OIT, 1997). One of the gas savingtechnologies highlighted by the Centre for the Analysis and Dissemination of Demonstrated EnergyTechnologies was the replacement of a gas forehearth with an electric forehearth. (A forehearth conditions themolten glass before it is fed to the forming machine). Savings using this technology were significant for thissection of the conditioning process (over 50%) while the payback on the investment was estimated at 1.5 years.The technology also improves yield (CADDET, 1989). We estimate that the forehearth accounts for about 20%of the gas consumption in the industry. Applying savings of 30% to a quarter of the container industry yields anational savings potential of 5-10 TBtu in 2015.

OIT, 1997. Glass Technology Roadmap Workshop. Document prepared by Energetics, Inc. Workshop held inAlexandria, VA on April 24-25th.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1989. “Electricforehearth with Indirect cooling saves energy.”

Ion-exchange system – float glass (glass)While chemically strengthened glass has better optical properties and is stronger than conventional, thermallytempered glass, it requires a lengthy treatment time that often makes it an uneconomical and inefficient optionfor manufacturers. Project partners are researching and developing several innovative systems using ion

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exchange, a process which substitutes one chemical ion for another, decreasing strengthening time. Thisshortened treatment time will make chemical strengthening a more commercially viable and cost-effectiveoption for glass manufacturers. Researchers will experiment with mixed alkali compositions that have higherexchange rates and with non-isothermal exchange processing, in which gradual glass bath temperature reductionincreases the exchange rate. This process results in increased energy efficiency—reducing glass mass in acontainer or float product by 25 percent could reduce the required energy more than 1MBtu/ton of glassproduced (OIT 1999). The ion-exchange process is an innovative way of inserting compounds evenly within aglass structure, however the claims of OIT on this technology are perhaps exaggerated. While the process canreduce the glass mass in a container, it is not quite clear that such a large energy savings will be had.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Integrated Ion-Exchange Systems forHigh-Strength Glass Products,” project fact sheet.

High levels of pulverized coal injection (iron and steel)Pulverized coal injection replaces the use of coke in blast furnaces. This in turn reduces coke production andenergy consumption in coke making, and reduces emissions and associated maintenance costs from coke ovens.Coal injection has increased in recent years. This increase is due in part to environmental regulations ofcokemaking and an aging stock of coke batteries in the U.S. In the blast furnace, the coal replaces part of thecoke that is used to fuel the chemical reactions. Coke is still used as support material in the blast furnace. Themaximum fuel injection depends on the geometry of the blast furnace and impact on the iron quality. Maximumtheoretical coal injection rates are around 560-590 pounds/ton hot metal (280-300 kg/tonne). In the U.S. thecoal injection rate varies. A 1994 survey of seven blast furnaces in the U.S. gave fuel injection rates between 80and 450 pounds/ton (41 and 226 kg/t) hot metal (Lanzer and Lungen, 1996). The highest injection rates, of 450pounds/ton (225 kg/t), have been reached at USX Gary (Schuett et al., 1997). O&M costs for the measure show anet decrease due to reduced coke purchase costs and reduced maintenance costs of existing coke batteries. Thisdecrease is partly offset by the increased costs of oxygen injection and increased maintenance of the blast furnaceand coal grinding equipment. We estimate the reduced operation costs on the basis of 1994 prices of steam coaland coking coal to be $14/ton. This is a low estimate, as cost savings of up to $30/ton are possible, resulting in anet reduction of 4.6% of the costs of hot metal production. We assume increased pulverized coal injection to 450lb/ton hot metal (225 kg/tonne, as reached at USX Gary blast furnace 13) for the large volume blast furnaces only(approximately 30% of total US production). Net fuel savings are estimated at 0.5 MBtu/ton hot metal (Worrell etal., 1999) while total energy savings are estimated at 4.1 TBtu (assuming a penetration rate of 15% by 2015).

Lanzer, W. and H.B. Lungen, 1996. “Roheisenerzeugung in Nordamerika,” Stahl und Eisen 116(8): 61-69.Schuett, K.J., and D.G. White, 1997. “Record Production on U.S. Steel Gary Works’ No. 13 Blast Furnace with

450 Pounds/THM Co-Injection Rates,” Iron and Steelmaker, 24(3): 65-68.Worrell, E., N. Martin, and L. Price, 1999. “Energy Efficiency and Carbon Dioxide Emissions Reduction in the

U.S. Iron and Steel Sector,” Berkeley, CA: Lawrence Berkeley National Laboratory (LBNL-41724).

Advanced coke oven gas co-generation technology (iron and steel)All plants and sites that need electricity and steam are candidates for cogeneration. Conventional cogenerationuses a steam boiler and back-pressure turbine technology to generate electricity. Steam systems generally have alow efficiencies and high investment costs. Modern cogeneration units are gas turbine based, using either asimple cycle system (gas turbine with waste heat recovery boiler), or a combined cycle integrating a gas turbinewith a steam cycle. Gas turbine systems mainly use natural gas. Integrated steel plants produce significant levelsof off-gases (coke oven gas, blast furnace gas, and basic oxygen furnace-gas). Specially adapted turbines canburn these low calorific value gases at electrical generation efficiencies of 45% (low heating value, LHV) butinternal compressor loads reduce these efficiencies to 33% (Mitsubishi, 1993). Mitsubishi Heavy Industries hasdeveloped such a turbine and it is now used in several steel plants, e.g., Kawasaki Chiba Works (Japan) (Takanoet al., 1989) and Hoogovens (The Netherlands). These systems are also characterized by low NOx emissions(20 ppm) (Mitsubishi, 1993). We assume that steel production facilities that have ready access to coke oven gas(55% of integrated plants) re-power their steam turbine generating systems with a combined cycle. This resultsin net primary energy savings of 7 TBtu. Investments for the turbine systems are $1090/kWe (Anon.,1997),resulting in a simple payback period of 6 years (Worrell et al., 1999).

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Anonymous, 1997. “Warmtekrachteenheid van 144 MWe bij Hoogovens” Energie en Milieuspectrum, October1997, p.9 (in Dutch)

Mitsubishi Heavy Industries, 1993. High Efficiency From Low BTU Gas, Outline of 145 MW Combined CyclePower Plant for Kawasaki Steel Corporation, Chiba Works, Mitsubishi Heavy Industries, Ltd., Tokyo,Japan.

Takano, H., Kitauchi, Y., and Hiura, H., 1989. Design for the 145 MW Blast Furnace Gas Firing Gas TurbineCombined Cycle Plant,” Journal of Engineering for Gas Turbines and Power, 111 (April): 218-224.

Worrell, E., N. Martin, and L. Price, 1999. “Energy Efficiency and Carbon Dioxide Emissions Reduction in theU.S. Iron and Steel Sector,” Berkeley, CA: Lawrence Berkeley National Laboratory (LBNL-41724).

On-site pickling HCl regeneration (iron and steel)Heated Hydrochloric acid (HCl) is used in the pickling line before the cold rolling mill to remove any metallicimpurities on the surface of the steel that is to be rolled. When the iron content of the pickling solution becomestoo high, the pickling solution is treated to remove the iron and recycle any HCl-solution to the pickling line.The acid is currently sent off-site for treatment or disposal, or it is recovered. Energy use for recovery may varybetween 0.2 and 5.2 kWh/ton cold rolled steel and between 20 and 125 kBtu/tonne steel (IISI, 1998). US DOEand NYSERDA have supported the development of recovery processes for the steel industry (DOE, 2000a) aswell as small-scale industries (DOE, 2000b) using different chemical reactions to treat the pickling solution.The fact sheets do not give energy consumption data for the new equipment, but still claim savings compared tooff-site treatment of the solution. Given the lack of this data. we are not able to independently evaluate theclaims, but estimate the primary energy savings at 1.5 TBtu (assuming 90 kBtu/ton energy savings in the steelindustry, 35 Million tons of cold rolled steel and a 50% implementation rate by 2015). No investment data isavailable.

International Iron and Steel Institute, 1998. “Energy Use and the Steel Industry,” Brussels, Belgium: IISI.U.S. Department of Energy, 2000a. “Energy-Saving Regeneration of Hydrochloric Acid Pickling Liquor,” Fact

Sheet NICE3, Washington, DC: US DOE-OIT.U.S. Department of Energy, 2000b. “Hydrochloric Acid Recovery System,” Fact Sheet NICE3, Washington,

DC: US DOE-OIT.

Intelligent inductive processing (iron and steel)Carburization, used to harden metal parts, now often happens by thermal heating or by inductive (electric)heating. Improved inductive (electric) heating technologies can improve product quality and reduce therejection rate due a better control of the carburization process. However, it is difficult to assess the energysavings from this technology, without detailed data on rejection rates and other process inefficiencies that couldpotentially be reduced by this process. The project developers claim savings of up to 1 Quad by 2015 if half ofall steel parts currently carburized would be treated with the improved technology (DOE-OIT, 2000). We areunable to independently evaluate this claim within the limitations of this project. However, as the technology isin the early stages of development, a 50% penetration rate by 2015 seems very high.

U.S. Department of Energy, 2000. “Improvements in Induction Heating Technology Can Increase Yields andImprove Quality,” Project Fact Sheet, Washington, DC: US DOE-OIT.

Improved EAF refractories (iron and steel)EAFs (and other furnaces as well as ladles) are lined with a refractory material to insulate and manage themolten metal. On average about 9 pounds/ton (3.5 kg/t) of steel of refractory material is needed (IISI, 1983).The refractory material wears off and has to be repaired or replaced. R&D programs in different countries areaimed to develop and select better refractories, although the choice will also depend on the specific furnace andraw material used. Increased lifetime of refractories will lead to less wastes, and may lead to indirect energysavings in steelmaking due to the reduce demand for refractory materials. These savings however may be offsetby increased energy demand for manufacture of the material itself. The new materials may also reduce costs dueto less downtime, and may lead to better control of the slag foaming process, an indirect energy efficiencyimprovement (DOE, 1999). Based on Worrell et al. (1999), we estimate that potential energy savings throughbetter slag foaming are 1-2 kWh/ton (additional to improved foamy slag practices). This will lead to electricitysavings of 1.8 GWh and primary energy savings of 0.2 TBtu (assuming a 30% implementation rate by 2015).

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International Iron and Steel Institute, 1983. “The Electric Arc Furnace,” Brussels, Belgium: IISI.U.S. Department of Energy, 1999. “Improving Refractory Service Life and Recycling Refractory Materials in

EAF Steel Production,” Washington, DC: U.S. DOE – OIT.Worrell, E., N. Martin, and L. Price, 1999. “Energy Efficiency and Carbon Dioxide Emissions Reduction in the

U.S. Iron and Steel Sector,” Berkeley, CA: Lawrence Berkeley National Laboratory (LBNL-41724).

Coke dry quenching (iron and steel)Coke dry quenching is an alternative to the traditional wet quenching of the coke. Dry quenching reducesparticulate emissions, improves the working environment, and recovers the sensible heat of the coke. Dry cokequenching is typically implemented as an environmental control technology. Various systems are used in Brazil,Finland, Germany, Japan, Russia and Taiwan (IISI, 1993). All recover the heat in a vessel where the coke isquenched with an inert gas (nitrogen). The heat is used to produce steam (approximately 800-1000 lb steam/toncoke), equivalent to 700-1000 kBtu/ton coke (Stelco, 1993; Dungs and Tschirner, 1994). For new coke plants thecosts are estimated to be $45/ton coke, based on the construction costs of a recently built plant in Germany(Nashan, 1992). However, it is very unlikely that new coke plants will be constructed in the U.S. Retrofit capitalcosts depend strongly on the layout of the coke plant and can be very high, i.e., $63/ton coke. Operating andmaintenance costs are estimated to increase slightly. Implementation of this technology will be driven byenvironmental regulation, as the investment is not economic based on energy savings alone.

Dungs, H. and U. Tschirner, 1994. “Energy and Material Conversion in Coke Dry Quenching Plants as Found inExisting Facilities,” Cokemaking International 6(1): 19-29.

International Iron and Steel Institute, 1993. World Cokemaking Capacity, Brussels, Belgium: IISI.Nashan, G., 1992. “Conventional Maintenance and the Renewal of Cokemaking Technology,” In: IISI, Committee

on Technology, The Life of Coke Ovens and New Coking Processes under Development, Brussels: IISI.Stelco, 1993. Present and Future Use of Energy in the Canadian Steel Industry, Ottawa, Canada: CANMET.

Non-recovery coke ovens (iron and steel)Coke ovens produce a lot of potentially hazardous chemicals as by-products. Traditionally, many of the by-products are recovered and used to produce chemicals. However, coke ovens produce a large amount ofemissions, both to the air and to water. Non-recovery coke ovens try to overcome this by burning all the by-product gas, based on older process designs. This results not only in fewer emissions, but may also result inlower capital and operating costs. However, non-recovery coke ovens may lea to higher SO2 emissions. Theonly energy recovered is waste heat of the flue gases, which in turn can be used to produce power. If used forpower approximately 700 kWh/ton coke can be produced (IISI, 1998). Various designs are available (Buss etal., 1999; Westbrook, 1999), and plants are operating in the U.S., Mexico and Australia. Inland Steel in the USstarted a new non-recovery coke oven in 1998, producing 1.33 Million tons of coke per year, while generating87 MW of power and supplying steam to Inland Steel. The technology actually needs a higher coal input (1.54t/t coke) than traditional coke plants (1994 US average 1.37 t/t) (Stelco, 1993). Hence, compared to a state-of-the-art coke oven using traditional technology a non-recovery coke oven does not save energy. However,compared to the average 1994 performance of US coke ovens, small primary energy savings may be achievedof 0.56 MBtu/ton coke if all heat is recovered to produce power. Assuming a penetration rate of 20% by 2015(due to air quality regulation) this would be equivalent to primary energy savings of 2.1 TBtu. Investment costsfor a non-recovery coke oven battery are estimated at 270-300 $/ton annual capacity (Stelco, 1993)

Buss, W.E., M.A. Merhof, H.G. Piduch, R. Schumacher and U. Kochanski, 1999. “Thyssen Still Otto/PACTINonrecovery Cokemaking System,” Iron and Steel Engineer 1 75 pp.33-38.

International Iron and Steel Institute, 1998. “Energy Use and the Steel Industry,” Brussels, Belgium: IISI.Stelco, 1993. Present and Future Use of Energy in the Canadian Steel Industry, Ottawa, Canada: CANMET.Westbrook, R.W., 1999. “Heat Recovery Cokemaking at Sun Coke,” Iron and Steel Engineer 1 75 pp.25-28.

Waste oxides recycling in steelmaking furnaces (iron and steel)Different processes in the steel mill produce wastes that contain a high concentration of iron oxides, e.g., millscale, sludges. These so-called ‘waste oxides’ can be landfilled or recycled. The waste oxides can be recycled inthe sinter process (adding to the iron ore) (Worrell et al., 1999) or the agglomerated waste oxides can berecycled in a steelmaking furnace (BOF or EAF). Research is ongoing in several parts of the world, e.g.,

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Luxembourg, Japan and the U.S. The U.S. research project aims at improved recycling of the waste oxides inthe BOF through better understanding and control of the melting and reduction process. Successful recyclingwould divert about 3 Million tons of waste oxides from landfills, containing about 50% iron. As energy is stillneeded to agglomerate and reduce the iron oxide, energy savings are mainly due to reduced need for mining ofiron ore and transport of the ore and wastes. The reduced landfilling and recycling will however result in largecost savings to the industry. However, the claims for energy savings of the U.S. project vary widely; from 30Billion Btu (AISI, 2000) to 15 TBtu (DOE, 1999). Assuming transport by rail open pit mining, (150 miles) andbarge (Great Lakes), we estimate the primary energy savings at 0.2 TBtu.

American Iron and Steel Institute, 2000. “Recycling of Waste Oxides in Steelmaking Furnaces,”http://www.steel.org/mt/projects/rswf/descrip.htm, accessed December 8th, 2000

U.S. Department of Energy, 1999. “Recycling of Waste Oxides in Steelmaking Furnaces,” Project Fact Sheet,Washington, DC: US DOE-OIT.

Heat recovery in sinter plants (iron and steel)Heat recovery at the sinter plant is a means to improve the efficiency of sinter making. The recovered heat can beused to preheat the combustion air for the burners and to generate high-pressure steam that can be run throughturbines. Various systems exist for new sinter plants (e.g., Lurgi EOS process) and existing plants can be retrofit(Stelco, 1993; IISI, 1998). The implementation is likely to be driven by environmental regulation, as the systemssubstantially reduce emissions (NOx, SOx, PM). In 1994, only 15% of the blast furnace feed consisted of sinter.We estimate the fuel savings associated with production of 13.4 Million tons (12.2 Mt) of sinter to be 0.5MBtu/ton (0.55 GJ/t) sinter, based on a retrofitted system at Hoogovens in The Netherlands. The retrofit isexpected to increase electricity use by 1.4 kWh/ton (1.5 kWh/t) sinter (Rengersen et al., 1995). The measure hascapital costs of approximately $3/ton sinter (Farla et al., 1997). We do not estimate costs for new sinter plantssince it is unlikely that such plants will be built in the U.S., due to the large investment required.

Farla, J.C.M., E. Worrell, L. Hein, and K. Blok, 1997. Actual Implementation of Energy Conservation Measures inthe Manufacturing Industry 1980-1994, The Netherlands: Dept. of Science, Technology & Society,Utrecht University.

International Iron and Steel Institute, 1998. “Energy Use and the Steel Industry,” Brussels, Belgium: IISI.Rengersen, J., Oosterhuis, E., de Boer, W.F., Veel, T.J.M. and Otto, J. 1995. “First Industrial Experience with

Partial Waste Gas Recirculation in a Sinter Plant,” Revue de Metallurgie-CIT 3 92 pp. 329-335 (1995).Stelco, 1993. Present and Future Use of Energy in the Canadian Steel Industry, Ottawa, Canada: CANMET.

Scrap pre-heating electric arc furnace (EAF) technologies (iron and steel)Scrap preheating is a technology that can reduce the power consumption of EAFs, using the waste heat of thefurnace to preheat the scrap charge. Old (bucket) preheating systems had various problems, such as emissions,high handling costs, and a relatively low heat recovery rate. Modern systems have reduced these problems, and arehighly efficient. Energy savings depend on the preheat temperature of the scrap. Various systems have beendeveloped and are in use at various sites in the U.S. and Europe, i.e., Consteel tunnel-type preheater, Fuchs FingerShaft, and Fuchs Twin Shaft (the latter only for new plants). All systems can be applied to new construction, andalso as retrofit technologies in existing plants. The new construction has already been included in the advancedEAF design. In this description we focus on retrofit scrap preheating systems.

The Consteel process consists of a conveyor belt with the scrap going through a tunnel, down to the EAF through a“hot heel”. Various U.S. plants have installed a Consteel process, including Florida Steel (now AmeriSteel,Charlotte, NC) New Jersey Steel (Sayreville, NJ) and Nucor (Darlington, SC), and one plant in Japan. Theinstallation at New Jersey Steel is a retrofit of an existing furnace (Lahita, 1995). Besides energy savings, theConsteel-process results in a productivity increase of 33% (Jones, 1997), reduced electrode consumption of 40%(Jones, 1997) and reduced dust emissions (Herin and Busbee, 1996). Electricity use can be decreased toapproximately 335-354 kWh/ton (370-390 kWh/t) (Herin and Busbee, 1996) without supplementary fuel injectionin a retrofit situation. We estimate the electricity savings to be 54 kWh/ton (60 kWh/t) for retrofit of existingEAFs. The investments are estimated to be $2M (1989) for a capacity of 400-500,000 ton per year (Bosley andKlesser, 1991), resulting in specific investments of approximately $4.4 to $5.5/t. The annual costs savings dueincreased productivity, reduced electrode costs and increased yield are estimated to be $1.9/t (Bosley and Klesser,1991).

http://www.steel.org/mt/projects/rswf/descrip.htm

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The FUCHS shaft furnace consists of a vertical shaft that channels the offgases to preheat the scrap. The scrap canbe fed continuously (4 plants installed worldwide) or through a so-called system of ‘fingers’ (15 plants installedworldwide). The Fuchs-systems make almost 100% scrap preheating possible, leading to potential energy savingsof 90-108 kWh/ton (100-120 kWh/t) (Hofer, 1997). The energy savings depend on the scrap used, and the degreeof post-combustion (oxygen levels). In the U.S. Fuchs systems have been installed at North Star (single shaft(1996), Kingman, AZ), North Star-BHP (double shaft (1996), Delta, OH), Birmingham Steel (finger shaft (1997),Memphis, TN). Two other Finger shaft processes have been ordered by Chapparel (TX) and North Star(Youngstown, OH). Carbon monoxide and oxygen concentrations should be well controlled to reduce the dangerof explosions, as happened at North Star-BHP. The scrap preheating systems lead to reduced electrodeconsumption, yield improvement of 0.25-2% (CMP, 1997), up to 20% productivity increase (VAI, 1997) and 25%reduced flue gas dust emissions (reducing hazardous waste handling costs) (CMP, 1997). A special system hasbeen developed for retrofitting existing furnaces called the Fuchs Optimized Retrofit Shaft, with a relatively shortshaft. Retrofit costs are estimated at $5.4/ton ($6/t) (Hofer, 1997) for an existing 100 t furnace. Using post-combustion the energy consumption is estimated at 308-317 kWh/ton (340-350 kWh/t) (Jones, 1997d) and 0.6MBtu/ton (0.7 GJ/t) fuel injection (Hofer, 1996). The production costs savings amount up to $4.5/t (excludingsaved electricity costs) (Hofer, 1997).

On average, we assume that retrofit of existing furnaces can lead to primary energy savings of 8.8 TBtu,retrofitting 40% of the EAF capacity (only large EAFs).

Bosley, J. and D. Klesser,1991. The Consteel Scrap Preheating Process, CMP Report 91-9, Center for MaterialsProduction, Pittsburgh, PA.

Center for Materials Production. 1997. Electric Arc Furnace Scrap Preheating. Tech Commentary, Pittsburgh,PA: Carnegie Mellon Research Institute.

Herin, H.H. and T. Busbee, 1996. “The Consteel Process in Operation at Florida Steel” Iron & Steelmaker23(2): 43-46.

Hofer, L.,1996. Electric Steelmaking with FUCHS Shaft Furnace Technology, Linz, Austria: Voest AlpineIndustrieanlagenbau Gmbh, VAI.

Hofer, L.,1997. Personal communication, Voest Alpine Industrieanlagenbau Gmbh, Linz, Austria, 25 September1997.

Jones, J. A. T. 1997a. "New Steel Melting Technologies: Part X, New EAF Melting Processes." Iron andSteelmaker 24(January): 45-46.

Lahita, J.A.,1995. “The Consteel Process in Operation at New Jersey Steel Corporation” Proceedings 5th

European Electric Steel Congress, Paris, June 19-23, 1995.

Recuperative burners in the rolling mill (iron and steel)Recuperative burners in the reheating furnace can reduce energy consumption, competing with low NOx oxy-fuelburners (see Martin et al., 2000). Energy use in a reheating furnace will depend on production factors (e.g., stock,steel type), operational factors (e.g., scheduling), and design features. Therefore, in practice energy consumptioncan vary widely between 0.6 and 3.0 GJ/t (Flanagan, 1993), with the low figures due to hot charging. Based on asurvey of 151 furnaces (representing 20% of Western world steel production) in Japan, Australia, UK and Canada,it was found that 18% of the furnaces had no heat recovery and 75% had separate heat recovery (Flanagan, 1993).As no specific U.S. data were available, we assume a similar distribution for the U.S. Installing recuperative orregenerative burners may require substantial changes in the furnace construction and may have high investmentcosts. New designs have typically low NOx emissions, despite higher flame temperatures. We assume installingregenerative burners in 20% of the furnaces, saving approximately 25% on fuel in these (mostly small) furnaces,based on experiences in the UK (Flanagan, 1993), or roughly estimated at 0.6 MBtu/ton product. We assumeinvestment costs $2.3/ton product. Assuming installing regenerative burners in 20% of the furnaces, this measurewill result in primary energy savings of 10.6 TBtu

Flanagan, J.M., 1993. “Process Heating in the Metals Industry,” CADDET Analyses Series 11, Sittard, TheNetherlands: CADDET.

Martin, N., 2000. Emerging Technologies Report

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Direct steel strapping production (iron and steel)The U.S. produces about 500,000 tons of steel strapping. Similar to near-net-shape casting technologies thistechnology aims to produce steel strap (and strip) from a rod. Though, the process is similar it uses a cold rod,instead of hot metal. It reduces the number of production steps in strapping production, and improves productquality. However, the process may still save energy compared to the conventional strapping production process(DOE, 1999). Given the specific nature of this process we are unable to independently evaluate the claimedenergy savings. The claimed energy savings (380 kWh/ton of strapping), though, seem relatively high, based onexperience with induction heaters (Flanagan, 1993). We assume lower electricity savings (200 kWh/ton ofstrapping) and implementation of this technology for 25% of the strapping production by 2015. This results inelectricity savings of 25 GWh, or 0.3 TBtu in primary energy by 2015. The technology will have productivitybenefits and increased product quality. This will make the technology economically more attractive.

Flanagan, J.M., 1993. “Process Heating in the Metals Industry,” CADDET Analyses Series 11, Sittard, TheNetherlands: CADDET.

US Department of Energy, 1999. “Method of Making Steel Strapping and Strip,” Fact sheet Inventions andInnovation Program, Washington, DC: US DOE-OIT.

Improved drying systems (lumber and wood productsThe U.S. lumber and wood products industry consumes an estimated 570 TBtu of primary energy. The dryingof lumber is one of the most energy intensive processes. We identified several drying technologies that couldpotentially reduce energy use in this sector. For permeable wood species the use of microwave and radiofrequency drying has shown promise, while for impermeable wood, OIT has sponsored research on a newtechnology that used high-speed microwave drying (OIT, 1998). Infrared drying has shown promise with thedrying of wood particulates with savings of 80% claimed beyond conventional gas drying processes (OIT,1999a). The use of a smart control system technology in the drying of red oak veneer yielded improved dryingefficiencies of 20-30% while increasing production by up to 10% (OIT, 1999b). Finally, several countries haveexperience in the application of waste heat pumps for wood drying which can eliminate fuel use (with anelectric heat pump) while increasing electricity consumption by 20% (de Beer et al., 1994; CADDET, 1994).We assume that 20% savings are possible, and estimate industry-wide savings of 12-20 TBtu in 2015.

OIT, 1998.“High speed microwave treatment for rapid wood drying”CADDET, 1994. Industrial Drying Technologies. Analysis series #12 CADDET, 1997, "Drying wood waste with flue gas in a wood fuel dryer"; CADDET 1995 "Improved drying of wood wool cement plates" OIT, 1999a “Long wave catalytic infra-red drying system for wood fiber.” OIT, 1999b “New Technology Revolutionizes Industrial Drying”

Heat recovery turbine (metalcasting)Heat from FeSi furnaces is converted into electric energy using a heat recovery turbine with the waste heatordinarily vented to the atmosphere. The approximately 750°C heavily dust-laden flue gas (10g/m3 silicon)from the furnaces passes a specially designed heat recovery boiler, which converts the gas heat into superheatedsteam for steam turbine power generation. In 1987, a turbine produced 90 GWh of electric energy,corresponding to 28 percent of the waste gas heat and 16.5 percent of the electric power consumption of thefurnaces. The hot gases from the furnaces are conveyed to the bottom of the boiler and the cooled gas is filteredin a bag filter unit. The boiler produces superheated steam at 460°C and 50 bar which is fed into a multi-stagereaction turbine, with capacity of about 22 MW (CADDET 1989), resulting in net annual primary energysavings of about 900 TBtu. Other potential applications outside the metal casting industry, include glass,cement, and steel production.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies. 1989.“Electricity Production by Heat Recovery at a Ferrosilicon Plant,” technical brochure.

Furnace process modeling and control (metal casting)The foundry cupola has historically been the primary method for melting iron because of its low cost andsimplicity. Recently, however, the need for pollution control devices and foreign competition has contributed to

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a decline in the domestic market. The design and application of automatic control technology for the cupolafurnace with reduce material and processing costs for cupola operation, reduce energy requirements andenvironmental impacts and improve product quality. This technology applies advanced intelligent controlmethods to the cupola melter in a furnace using pig iron, scrap steel, cast iron scrap, foundry return scrap, andferroalloys to a specified tapping temperature and chemical composition. An 18-inch experimental researchcupola was designed and constructed. A neural network model of the cupola, and techniques for training theneural network have been developed. Exact energy savings have not yet been determined.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Intelligent Control of the Cupola Furnace,”project fact sheet.

http://www.oit.doe.gov/factsheets/metalcast/pdfs/cupola2.pdf

Unconventional yield improvement methods (metal casting)Substantial yield increases are possible by using alternatives to current rules for risering design. Researchers areidentifying techniques for decreasing the size and number of risers required to produce quality castings. Thesetechniques include:- conventional methods (feeding rules, riser insulation, block chills)- unconventional methods (active heating and cooling, directional solidification)

Novel yield improvement techniques are being developed promoting directional solidification through a varietyof active heating/cooling schemes. It is envisioned that the techniques will allow certain castings to be producedwith a yield that is at least 25 percent higher than the current level. Energy savings in melting estimated to be1.8 trillion BTUs per year when yield is increased by 10 percent.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Unconventional Methods for YieldImprovement,” project fact sheet. http://www.oit.doe.gov/factsheets/metalcast/pdfs/yieldproj.pdf

Simulation programs for process management (metal casting)A simple qualitative method is being developed to visualize potential design problems in die-casting. Thesoftware, CastView, is intended to help minimize flow-related filling problems, thermal problems in the diecasting die, and solidification-related defects in the cast part. CastView’s intended uses are different fromtypical simulation programs. It is designed to complement numerical simulation by quickly providing the partdesign team with a limited amount of data relevant to thermal and flow problems in die-castings. The analysis isqualitative and provides information based only on the part geometry. Material properties are not required andprocess details are not required. This enables analysis times of only a few minutes. Simulation programs forprocess management addresses thermal issues by allowing the user to locate and display thick and thin sectionsin the part and thin sections in the die. Thick sections in the part will typically correlate well with the lastsections to solidify and with shrinkage porosity. Thin sections in the part may present premature solidification.Detecting problems early in the process enables the die caster to negotiate a modification of the part geometrywith the part designer to achieve a more castable part. This tool will greatly increase the ability of die castersand designers to communicate with one another and to quickly evaluate a large number of design alternatives.Simulation programs for process management will lead to better designs, resulting in less scrap, feweroperational problems and a reduction in associated energy consumption. Exact energy savings are unknown.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Visualization Tools for Die Casting,”project fact sheet.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies. 1997. “Castingprocess improved using simultaneous engineering,” technical brochure.

———. 1994. “New simulation program predicts quality of castings,” technical brochure.

New metal heating approaches (metal casting)Metal casting is among the most energy-intensive industries in the United States. The heating and melting ofmetals consume large amounts of energy. It has been estimated that as much as 20 million Btu are required tomelt and cast one ton of salable iron castings, although 13 to 15 million Btu per ton is more typical. Most of thisenergy use (an average of 55 percent of total energy costs) can be attributed to melting. There are several

http://www.oit.doe.gov/factsheets/metalcast/pdfs/cupola2.pdf

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innovative casting processes that can reduce this energy use. They include: squeeze casting, semi-solid metalcasting, the FM process, and rheocasting and thixomolding. These innovative casting processes can lower theenergy used in the melt by 15-20 percent. The 1994 energy use of the metal casting industry was approximately200 trillion Btu. Utilizing new metal heating approaches could result in an energy savings of 4 trillion Btu by2015 if 20 percent of all forgers adopt energy saving casting processes.

U.S. Department of Energy, 1999. Energy and Environmental Profile of the U.S. Metalcasting Industry.Washington, D.C.: USDOE

Die casting copper motor rotors (metal casting) Though it conducts electricity less efficiently than copper, aluminum is preferred for manufacturing conductorsin electric induction motor rotors. Aluminum can be die cast relatively easily and is the industry's preferredfabrication material. Before aluminum die-casting was developed, rotors were hand-fitted with individualcopper conductors that were then joined into a complete rotor conductor system by hand labor. Die castingcopper conductor rotors (CCRs) has not been successful because conventional casting molds suffer thermalshock, shortening mold life and increasing production costs. ThermoTrex Corporation proposes to fabricatecost-effective molds using high-temperature, thermal shock-resistant materials designed to perform foreconomically acceptable life spans of thousands of casting cycles (OIT 1999). This technology responds to theCongressional mandate to increase the electrical efficiency of integral horsepower motors sold in the UnitedStates (OIT 1999). Electrical motors are used throughout U.S. manufacturing agricultural irrigation. Motorsaccount for more than 60 percent of all electricity use in the Nation. The market for electric motors totals about$35 billion per year internationally and about $10 billion in the United States. Die copper motor rotors isexpected to improve motor efficiency by 15 percent to 20 percent.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Die Casting Copper Rotor Motors,” projectfact sheet.

http://www.oit.doe.gov/factsheets/nice3/pdfs/25029motorrotor.pdf

Ceramic filters (mining)Filters remove heavy metals resulting from enameling processes. Typically, Polymer Membrane Filters areused, but are unsatisfactory for two main reasons. Firstly, the membranes tend to block easily, reducingcapacity from 3000 liters per hour (l/h) to 500 l/h. This blockage requires daily cleaning, increasing the workinghours on the installation. Secondly, a large pump capacity is necessary to maintain pressure across themembrane. In response, Ferro Techniek BV developed ceramic filters to replace the polymer membranes, andusing an existing prototype, changed the pump configuration to obtain the required pressure build-up. One ofthe demands to be met was a guaranteed capacity of 1,000 liters per hour. Immediately after installation,capacity was 2,400 l/h, however, capacity dropped to and stabilized at 800 l/h. The results of this project areuseful to any industry that requires the removal of very small particles from effluent water (CADDET 1994).This measure offers dramatic increases in volumetric flow rate in a given process, rather than marked energysavings. The overall productivity of a process will be increased while pumping energy remains the same.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1994.“Ultrafiltration,” technical brochure.

Vibration fluidized bed separation (mining)In large mining operations, a thousand or more tons of coal may be processed each hour. The best large-scaleseparation method available until now has been water flotation, which requires drying the material afterseparating and disposing of the wastewater. To reduce the energy needed to dry mined coal and reduce thegeneration of wastewater, a new method of separating coal through complex-mode vibration in a fluidized bedhas been developed. These innovative vibrating beds eliminate the need to process the coal through a wet slurryremoval process, saving energy and time. Unlike simple linear vibrations, the adjustable vibration inducingsystem can be tuned to produce optimum separations from a variety of different materials. This process isprojected to save one million gallons of fuel oil (0.138 TBtu by 2015) and $500 million in expenditures fromenergy for drying if the new process is used for 10 percent of the coal produced annually in the United States(OIT 1999).

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Office of Industrial Technology, U.S. Department of Energy, 1999. “Density Separation in Complex-ModeVibration Fluidized Beds,” project fact sheet.

Ramex tuneller (mining)The Ramex Group has developed a new method of rock cutting that uses impact to fracture and create slots inhard rock. The Ramex IKC cutting tool is as easy to use as a hydraulic breaker, it produces larger rock cuttingsfor easier handling and allows the energy-efficient mining of any shape opening in rock. In addition, Ramex slotcutting eliminates the costly and energy intensive use of drill holes needed to place explosives. The diesel-powered cutting head has an injector that combusts fuel, creating an explosion that drives a piston forward in abounce chamber. This forces the cutting head against the rock face at the rate of eight or nine times per second.The first generation cutter was field tested on a free-piston, diesel driven, impact ram developed by Ramex. Theram developed 3,200 foot-pounds force (ft-lbf) at 460 blows per minute (bpm) and excavated hard rock at a rateof over sixteen cubic yards per hour (16 cu. yd./hr.) (i.e., 36 tons/hr.) (OIT 1999).

Office of Industrial Technology, U.S. Department of Energy. 1999. “Ramex Tuneller,” project fact sheet.

Ammonia absorption refrigeration unit (petroleum refining)The U.S. petroleum refining industry is one of the largest energy consumers, with a primary energyconsumption of roughly 3,300 TBtu in 1994. Modern complex refineries use about 6-10% of the energy contentof the incoming oil to process and produce final products. Flaring in refineries occurs when waste refinery gascan not be used in boiler systems and is burned. The propane fraction of this waste stream represents a valuableco-product that could be salvaged. One DOE sponsored project funded the development of an ammoniaabsorption unit run on waste heat chilled the gaseous waste stream from the reformer to recover 200 barrels perday (1% of output) from a Denver refinery. This technology boosted profit (by $900,000 annually) and paid foritself in less than 2 years (OIT, 1999). We assume that potential savings in the U.S. from reduced flaring couldbe 2-5 TBtu in 2015.

OIT, 1999. “Ammonia Absorption Refrigeration Unit Provides Environmentally-friendly Profits for an OilRefinery.”

Hydrogen purification improvements (petroleum refining)Hydrogen is used in petroleum refineries to desulfurize petroleum products, as well as to upgrade production tolighter end products. However, the production of hydrogen is energy-intensive, and produced by steamreforming or partial oxidation of hydrocarbon feedstocks (e.g., natural gas, HC residues). Total hydrogen use isestimated at 874 TBtu (US DOE-OIT, 1998). The hydrogen-using processes produce tailgases with a loss ofsome hydrogen. Given the high energy content of these gases it is worthwhile to recover the hydrogen.Technologies used for the separation of hydrogen include PSA and membranes, while oleophobic/hydrophobictreatment can be used to remove any liquids. Increasingly refineries are installing hydrogen recovery processes.Improvements in the separation efficiency can further increase hydrogen recovery, as well as save oncompression energy (membranes), or lead to reduced costs. Argonne National Laboratory is developing a long-term technology using microwaves to split H2S into hydrogen and sulfur, potentially reducing the energy needsfor hydrogen makeup (ANL, 1999). However, it is impossible to evaluate future energy use of this technologyyet, as the development is in the early stages. For 2015 we expect further development of current technologiesto increase efficiency and lower costs. We assume an increased recovery of 1% overall, leading to energysavings of approximately 9 TBtu. Payback periods vary depending on the type and size of the installation,between 1 and 2 years (Shaver, 1991).

ANL, 1999. “Recovering Hydrogen and Sulfur from Refinery Wastes,” Argonne, IL: Argonne NationalLaboratory (http://www.es.anl.gov/htmls/refinery.wastes.html).

Shaver, K.G., G.L. Poffenbarger and D.R. Grotewold, 1991. “Membranes Recover Hydrogen,” HydrocarbonProcessing 6 71 pp.77-80.

US DOE – OIT, 1998. “Energy and Environmental Profile of the U.S. Petroleum Refining Industry,”Washington, DC: U.S. Department of Energy – Office of Industrial Technologies.

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Selective oxidation of benzene to phenol (petroleum refining)Currently, the chemical industry uses the three-step “cumene process” to produce 95 percent of the 4.5 billionpounds of phenol it requires annually for manufacturing phenol-formaldehyde resins (OIT 1999). A proposednew process, still being developed, would convert benzene to phenol in only one step and would eliminate theneed to neutralize acids, separate organic products, or to be concerned with a potentially unstable intermediateproduct in the cumene process. Theoretically, the new process also produces no by-products, whereas thecumene process leaves several hazardous compounds that must be disposed of properly and acetone that mustbe sold to make the process economical. The new process could generate considerable energy savings andreduce by-products and hazardous wastes. Further, phenol is the second-largest commodity produced from theinexpensive raw material, benzene. The bottom line result for industry will be production cost savings,reduction in environmental impacts, and more effective carbon management. Phenol production normallyconsumes approximately 7,850 Btu/lb. (OIT 2000). This technology could reduce this figure by approximately10 percent leading to an estimated energy savings of 4 trillion Btu in 2015 (OIT 2000). Office of Industrial Technology, U.S. Department of Energy, 1999. “New Catalyst Technology for the Selective

Oxidation of Feedstock Aromatic Compounds to Commodity Chemicals,” project fact sheet.http://www.oit.doe.gov/factsheets/chemicals/pdfs/feedstock.pdf

Office of Industrial Technology, U.S. Department of Energy, 2000. “Energy and Environmental Profile of theU.S. Chemical Industry.” Washington, D.C.

Liquid membranes in refining (petroleum refining)Membrane separation process can be treated as a good alternative traditional filtration, ion exchange andchemical treatment systems. Although the basic scientific principles behind membrane technology have beendeveloped in the 1950s, it was not until the 1970s that crossflow membrane technology, in the form of UF andRO, began to be recognized as an efficient, economical and reliable separation process. Purification systemsutilizing crossflow membrane filtration, such as reverse osmosis (R0), nanofiltration (NF) or ultrafiltration (UF)can be a good alternative to conventional systems. Membranes also offer an alternative to liquid-liquidextraction, a technology used to separate aqueous, organic, or azeotropic mixtures. Liquid membranes canperhaps be utilized to replace the energy intensive cracking of petroleum feedstock into the various saleablefractions. The annual energy use of fluid catalytic cracking, most likely the process that liquid membraneswould replace is just over 100 trillion Btu per year in the U.S. Liquid membranes could reduce the energy useof the cracking process by 10% or more. The cost of liquid membrane unit is potentially much lower than thecost of a conventional cracking unit, but equipment retrofits and process changes are generally frowned upon byrefinery operators.

U.S. Department of Energy. Energy and Environmental Profile of the U.S. Petroleum Industry. 1998.Blok, et al. 1994.

Low profile FCC (petroleum refining)Petroleum refiners use fluid catalytic cracking (FCC) technology to convert crude oil to blending stocks for usein gasoline, diesel, and heating oil. Construction and operation of the 200-foot tall FCC units are expensive, andprocess control improvements are slow to be adopted. Process Innovators, Inc., will demonstrate a new, low-profile FCC process that will increase yields and lower costs for any size of refining operation (OIT 1999). Byusing multiple reactors instead of the current single-reactor technology, the company will be able to confine theunit’s height to 50 feet and also incorporate advances such as a short residence time, rapid disengaging, a highcatalyst-to-oil ratio, and the matching of feed reactivity to catalyst activity. Because of its low profile design,this technology can be scaled down cost-effectively. This will enable the small refiner of the future to becompetitive. The projected annual energy savings, as reported by the DOE Office of Industrial Technologiesare estimated at 122 billion Btu for each unit processing 10,000 barrels of finished product daily. Reduced airemissions of more than 10,000 tons per year per unit are also projected (OIT 1999). These figures would applyif industry-wide adoption of this technology took place. This however is a highly unlikely scenario due to thehigh capital cost of petroleum refining equipment.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Catalytic Cracking Distillation Plant,”project fact sheet.

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Fluidized bed reactor for plastics recovery (plastics)In the United States plastics production has grown significantly over the last two decades, with the productionof plastics accounting for 2% of primary energy use in manufacturing (400 TBtu). While some progress hasbeen made in recovering plastics from various waste streams, the overall recovery rate of post-consumer wastein the U.S. is very low. Thermoset plastics are particularly challenging to recycle since they can not be re-melted without destroying their original properties. The U.S. Department of Energy has been funding researchon a procedure for recovering chemicals from thermoset plastics. This process involves the use of a smallfluidized bed reactor and distilling out high-value monomers (OIT, 1999). A demonstration reactor has beenbuilt and Merichem corporation has been testing products. Initial claims are that savings of 44 TBtu can beachieved in the U.S. by 2020, although we have not been able to fully evaluate this calculation.

OIT, 1999. “Production of Chemicals from Thermoset Plastics.” Project fact sheet.

Heat recovery in plastics (plastics)The manufacturing processes of plastic products consume a large amount of energy. Electric heaters are used todry and melt plastic materials, and chilled water from a chiller is used to cool and solidify molded products.Thus, heating and cooling are carried out in the same process at the same time. The processes of kneading andmolding use a fair amount of electrical energy through their oil hydraulic circuits. The temperature of hydraulicfluid in these circuits must be controlled to stabilize the operations of molding machines. These hydrauliccircuits discharge large amounts of waste heat. On the other hand, an air-conditioning system for a moldingfactory of plastic products, which is indispensable to sophisticated quality control and improvements to laborenvironment and productivity, consumes only about half the amount of electrical power (CADDET 1991a,b).By recovering the waste heat from the hydraulic circuits and the molding processes, a molding factory in Ibarki,Japan manufacturing plastic electrical parts utilizing the excess heat as the heat source for a water-cooled heatpump air-conditioning system. This saved electric power and brought excellent economical benefits. Addingheat recovery to this system can reduce energy usage by approximately 15 percent. The 2015 impact could be20 TBtu.

[CADDET]Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1991a. “HeatRecovery from Plastic Injection Molding Machines at a Factory in Inchinnan, Scotland,” technicalbrochure.

———. 1991b. “Waste heat recovery from the manufacture of plastic products,” technical brochure.

Water as cooling refrigerant (plastics)As a result of a research and development project initiated by the Danish Technological Institute a 2 MWcooling plant was built in 1994 using only water as refrigerant for process cooling water. Since 1995 theinstallation has been in operation refrigerating process water from 600 injection molding machines producingLEGO bricks around the clock. Substantial environmental benefits result from the use of water as refrigerant.Energy savings are estimated to approximately 20-50 percent compared to traditional technology. The processresembles a normal gas compression cycle (evaporation, compression, condensation and expansion) with adifference of being an open cycle where the water is used as primary and secondary refrigerant. 13.5°C water isled to the evaporator where it expands to approximately 11mbar corresponding to a saturation temperature of8°C. 1 percent of the water evaporates and the remaining 99 percent is chilled to 9°C. The evaporated water,now the primary refrigerant (working fluid), is compressed in a two-stage turbo compressor system withintermediate cooler. The water vapor is condensed directly on the injected cooling tower water, which is heated4-5°C to a temperature very close to the condensing temperature. The temperature difference is less than 1-1.5°C. All non-condensable gasses must be removed from the cooling water before entering the condenser, whichhappens in an efficient two-stage deaeration system. Total project budget for the LEGO plant was 20 millionDKK ($2.3 million USD). The prototype demonstration plant at LEGO cost 9.3 million DKK ($1.0 millionUSD). The estimated payback period for this technology is 36 months. Within in a complete operational period,comparable measurements show that the power consumption of the new plant represents approximately half ofthe consumption of a conventional R22 refrigeration plant placed at LEGO systems A/S. In relation totraditional plant the price would be higher. Further development is at this moment carried out in order to reducethe overall production costs of the plant.

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[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies. "Cooling plantat LEGO uses water as refrigerant.” Technical brochure.

Tunnel kiln (plastics)In order to shield television tubes from the influence of the earth's magnetic field, special backs are built in,which requires a special structure of the glass crystals. This is obtained by subjecting the tubes to a three-stageheat treatment in three separate electric kilns: first stage: decarbonizing and recrystallizing. This takes place ina kiln at 700°C. Second stage: steam-blackening in a second kiln, where steam is injected at 650°C. This causesan oxide layer to form, which improves the corrosion resistance and the heat emission. Third stage: controlledcooling in a third kiln. In the new situation, a single, continuous kiln, consisting of three sections separated byair locks will replace these kilns. The result will be a reduction in electricity of approx. 60 percent, because theaverage passage time will be shortened, the separate sections can be heated continuously and the tubes onlyhave to be heated up once. Also, the use of steam will become more efficient, as at present the steam pipes haveto be blown through before each batch enters the second stage, in order to obtain dry steam. The technique canbe used at companies where heat-treatments are common, especially in the ceramics, steel and metal industry.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1994.“Blackening of the Steel Back Caps for Television Tubes,” technical brochure.

Heat recovery – printing (printing)Printing processes are generally done in the presence of heat. Normally the waste heat is vented to theatmosphere. A novel technology has been developed to capture some of the waste heat and use it for drying ofthe wet printing ink. After each stage of a multicolor printing process, the ink is dried with hot air, and heated ina hot oil heat exchanger. The drying air, which is polluted with hydrocarbons (used as solvents for the ink), isled to the afterburner. Prior to entering the afterburner, the air is preheated in a heat exchanger, using the wasteheat of the clean air flowing to the exhaust. In the afterburner the hydrocarbons are converted catalytically, withnatural gas as an additional fuel. The waste heat of the exothermic process is used to heat the hot oil for thedrying air heat exchanger, for space heating and to preheat the polluted drying air entering the afterburner. Thesavings of this technology are approximately proportional to the number of colors that have been printed, somulti-colored prints result in a high energy savings.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1993. “Heatrecovery after catalytic combustion in a printer's shop,” technical brochure.

Flotation deinking for stickies removal (pulp and paper)The pulp and paper industry is a large industrial energy user, and consumed about 13% of U.S. manufacturingenergy use in 1994. Energy requirements for the production of paper from virgin pulp are significant, given thehigh energy requirements associated with pulp production processes and for paper drying. Increasing the use ofrecycled paper can have a significant impact on reducing energy use. Flotation deinking is the current bestpractice for processing recycled pulp. In flotation deinking, recovered paper is dumped into the top of thehydrapulper and is pulp and blended into a slurry. The pulp exits at the bottom of the machine while theimpurities exit out of the side. Current flotation deinking technologies have trouble handling wax and stickycontaminants that are part of the stock of old corrugated containers (OCC). The U.S. department of energy andVoith Paper sponsored research on new separation methods to handle the particle size, shape, and density ofwax and stickies without incurring excessive fiber losses (OIT, 1998). If successful this technology can bothreduce cost penalties associated with disposing of wax and sticky contaminants and can provide increasedrecovered paper thereby lowering production costs. A related technology that could be promising forphotocopier waste is column flotation, which has shown in early trials a production of higher quality pulp withsimilar yields (Chaiarrekj et al. 1999). Costs for the construction of recycled pulp processing facilities areestimated at $485/tonne pulp in the analysis although significant operation and maintenance cost savings arepossible ($74/tonne pulp). Energy savings in 2015 will depend on the amount of OCC paper that can berecovered for recycling.

OIT, 1998. “The Removal of Wax Stickies from OCC.”

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Martin, N.; Anglani, N.; Einstein, D.; Khrusch, M.; Worrell, E.; Price, L.K. 2000. Opportunities to Improveenergy Efficiency and Reduce Greenhouse Gas emissions in the U.S. Pulp and Paper Industry.Lawrence Berkeley National Laboratory. Report No. LBNL-46141.

Chaiarrekij, H.; Dhingra, H.; Ramarao, B.V, 1999. “Deinking of Recycled Pups Using Column Flotation:Energy and Environmental Benefits,” in Industry and Innovation in the 21st Century Proceedings of the1999 American Council for an Energy Efficient Economy summer study on energy efficiency inindustry. Washington, DC: ACEEE.

Bacterial reduction of sulfur to sulfide in kraft mills (pulp and paper)The pulp and paper industry is a large industrial energy user, and consumed about 13% of U.S. manufacturingenergy use in 1994. Pulping is one of the most energy intensive process stages in an integrated mill. In a typicalpulp mill black liquor is concentrated and combusted in a large recovery boiler. The smelt is then recausticized(after being formed into green liquor), into white liquor which is re-used in the pulping process. Capacityconstraints in the recovery boiler can be a bottleneck for mill expansion. One technology being supported by theU.S. Department of energy is the bacterial reduction of oxidized sulfur produced during pulping to sulfide. Thisprocess reduces the load on the kraft recovery boiler and enhances longetivity (OIT, 1998). It is not clear towhat extent furnace efficiency will be improved from the technology, although it will bring about cost-savingsin operation. The technology is still in the research and demonstration phases.

OIT, 1998. “Biological Augmentation of Kraft Cycle.”Martin, N.; Anglani, N.; Einstein, D.; Khrusch, M.; Worrell, E.; Price, L.K. 2000. Opportunities to Improve

energy Efficiency and Reduce Greenhouse Gas emissions in the U.S. Pulp and Paper Industry.Lawrence Berkeley National Laboratory. Report No. LBNL-46141.

Press drying (pulp and paper)The pulp and paper industry is a large industrial energy user, with an estimated primary energy consumption of2,970 TBtu in 1994. In current drying practices, after the paper is formed and pressed and no more water can beremoved mechanically, the sheet moves through a series of 40-50 steam heated cylinders, with the finalconsistency being about 90-95% solids content. In press drying the sheet is pressed between two hot surfaces orpressing cylinders at a temperature of 100-250°C. In most cases the cylinders are installed in the conventionalpressing section of the machine. Energy savings have been estimated at 5-30% and the drying rate can beincreased by 2-10 times conventional processes (de Beer, 1998). We estimate a savings of 10% and apply this to15% of 2015 paper throughput for a 2015 savings potential of 50 TBtu.

De Beer, J. 1998. Potential for Industrial Energy efficiency Improvement in the Long Term. PhD thesis. Utrecht,the Netherlands: Utrecht University.

Biopulping (pulp and paper)The pulp and paper industry is a large industrial energy user, and consumed about 13% of U.S. manufacturingenergy use in 1994. Pulping is one of the most energy intensive process stages in an integrated mill. Biopulpingis a process in which the wood chips are pre-treated with biological agents to degrade the lignin. The chips aretreated for a 1 to 4 week period that can create space constraints in some mills. Electricity savings frombiopulping are estimated at 30%, or 512 kWh/ton pulp (565 kWh/t pulp) compared to mechanical refining,however there are some additional steam requirements estimated at 0.4 MBtu/ton (0.5 GJ/t) pulp (Martin et al.2000). Estimates for the investment in biopulping facilities are $25/ton pulp while operations and maintenancecosts are expected to increase $8.5/ton pulp (Scott and Swaney, 1998). The biopulping may extend machine lifein mills and improve product quality. The system has been demonstrated in several large-scale tests but is notcommercial as there are several unresolved technical issues. Based on a recent analysis for the U.S. pulp andpaper industry (Martin et al. 2000), we assume a potential energy savings of 4 TBtu based on the installation ofthe technology in 20% of all mechanical pulp mills with output of less than 600 tons per day.


Scott, G.M. and Swaney, R. 1998. “New technology for papermaking: biopulping economics.” Tappi Journalv.81, no. 12.

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Fluidized bed combustion for sludge/bark/wood fiber waste (pulp and paper)The pulp and paper industry is a large industrial energy user, with an estimated primary energy consumption of2,970 TBtu in 1994. Unique to this sector is the fact that 50% of the energy supplied for the industry is biomass(black liquor, wood wastes). This biomass is burned either in large recovery boilers or in biomass boilers toraise steam for process use. There are however additional opportunities to utilize additional biomass resourcesand offset the need to purchase commercial fuels through the use of fluidized bed combustion technology. TheTomakomai Mill at Oji paper company installed a fluidized bed boiler (replacing waste heat and bark boilers) tocombust pulp sludge from the waste water treatment system.. The heating value of the pulp sludge (as fired was4 GJ/t) and the boiler was able to generate electricity savings that yielded a project payback of 2 years(CADDET, 1991). A similar system concept installed by a Dutch newsprint manufacturer, Parenco BV, with apayback of less than 4 years (CADDET, 1993). Applying this technology to 50% of the mills where de-inkingsludge is available could yield savings of 20-30 TBtu.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1991. “Fluidisedbed combustion boiler for power generation.”

———, 1993. “Steam production by burning residual material in a fluidised bed boiler.”

Air/Steam impingement drying (pulp and paper)The pulp and paper industry is a large industrial energy user, with an estimated primary energy consumption of2,970 TBtu in 1994. In current drying practices, after the paper is formed and pressed and no more water can beremoved mechanically, the sheet moves through a series of 40-50 steam heated cylinders, with the finalconsistency being about 90-95% solids content. Air and steam impingement drying involves blowing hot air orsuperheated steam (300°C) against the wet sheet. For steam impingement drying 10-11 tons of superheatedsteam is required to dry 1 ton of paper, with an additional 4-9 tons to cover losses and inefficiencies. Thistechnology can be combined with existing technologies (de Beer et al., 1998). Fuel savings estimates are 10-40% for air impingement drying and less (10-15%) for steam impingement. Electricity requirements areexpected to slightly increase in the air impingement process (0-5%) and slightly decrease in the steamimpingement process (5-10%). Although the complexity of the technology increases investment costs can bereduced due to the shortening of the drying section (de Beer, 1998). (Fleming, 1997) claims that the system iseconomical with respect to gas consumption and noted that trials showed a 13% increase in bonding strength.Air impingement drying has been applied for sanitary paper while considerable R&D is still required in thesteam impingement drying technology (de Beer, 1998). We estimate a savings of 10% and apply this to 15% of2015 paper throughput for a 2015 savings potential of 50 TBtu.

De Beer, J. 1998. Potential for Industrial Energy efficiency Improvement in the Long Term. PhD thesis. Utrecht,the Netherlands: Utrecht University.

Fleming, 1997. Linerboard Technology Developments Changing "Round and Brown" Image. Pulp and Paper.Volume 71, Issue 6.

Freeze concentration mill effluent (pulp and paper)Freeze concentration separates mixtures by crystallizing one or more components and has the potential toproduce and almost completely dry product (de Beer et al. 1994). While this process shows promise in the foodprocessing industry (see technology write up in this appendix) it also can be applied to the pulp and paperindustry and other sectors as well. In particular, research work sponsored by the Office of IndustrialTechnologies in the U.S. Department of Energy has been focusing on the application of freeze concentration inrecovering volatile and complex contaminants found in mill effluent. Energy consumption for this system is15% less than energy required for evaporation and early demonstration projects found that 96 percent of theadsorbable organic halides and chlorides were removed from an elemental chlorine free bleaching effluent(OIT, 1998). We estimate that the technology could be applied to half the mills with a potential energy savingsof 5-10 TBtu in 2015.

De Beer, J.; K, Blok, M.T. van Wees, and e. Worrell. 1994. Icarus-3. The Potential of Energy efficiencyImprovement in the Netherlands up to 2000 and 2015. Utrecht, The Netherlands: Utrecht University.

OIT, 1998. “A New Freeze Concentration Process for Minimum Effluent Processes in Bleached Pulp Mills.”

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Fiber loading equipment for PCC (pulp and paper)In the manufacture recycled waste paper pulp, precipitated calcium carbonate (PCC) filler can be added toincrease brightness, remove color, and reduce residual ink and contaminants. Currently PCC is produced in asatellite plant adjacent to a paper mill. A new Voith fiber loading process produces PCC by adding calciumhydroxide to moist pulp reacted with carbon dioxide in a pressurized refiner. This technology has a 30% costsavings, and an estimated energy savings of 2 MBtu/ton recycled paper (OIT, 1999). Additional benefits includereduced solid waste production. A demonstration facility has been built and the technology is nowcommercially available. Applying the technology to 25% of recycled paper production would yield a savings of15 TBtu in 2015.

OIT, 1999. “Fiber Loading for Paper Manufacturing”

Thermodyne pulp dryer (pulp and paper)In situations where the pulp and paper mills are not located in the same area, then pulp must be dried. Marketpulp is dried on average to 20% water, and then shipped to a paper mill where it is re-pulped (Martin et al.2000). Pulp drying is an energy intensive process that consumes an estimated 3.9 MBtu/ton of steam and anestimated 140 kWh/ton electricity (Martin et al. 2000). The Thermodyne evaporator produced by Merrill AirEngineers is a higher efficiency technology capable of replacing conventional systems. The dryer producessuperheated steam in a sealed environment that is directed onto the material being dried rather than having thewater vapor exhausted outdoors (OIT, 1997). Energy requirements are reduced by 50% compared toconventional technology (OIT, 1997). We estimate potential energy savings of 10 TBtu based on an applicationof the technology to half the dried pulp in the U.S.


Office of Industrial Technology, U.S. Department of Energy, Impacts report, 1997. “Thermodyne evaporator, amolded pulp products dryer.”

Super pressurized groundwood pulping (pulp and paper)Pulp production is one of the largest energy consumers in an integrated mill. Pressurized groundwood pulpingwas first developed in Scandinavia in the 1970s. In this process, grinding takes place under pressure wherewater temperature is high (greater than 95°C) thereby allowing for higher grinding temperatures without steamflashing (Martin et al. 2000). Savings estimates are significant (36% electricity savings) as compared toconventional thermomechanical pulping (CADDET, 1992). Super-pressurized groundwood achieves bettersmoothness and opacity. Installation costs are estimated at $200/ton with a savings in O&M of $2/ton (Martin etal. 2000). Compared to atmospheric grinding, the strength properties of super pressurized groundwood pulpimprove by 30-50% (EPA, 1994). Based on an application of the technology to 50% of thermomechanical pulpwe estimate a savings potential of 5-10 TBtu.


[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies. 1992. SuperPressurized Groundwood Process Produces High Quality Mechanical Pulp. Sittard, The Netherlands:CADDET.

U.S. Environmental Protection Agency (EPA) -- Office of Water. 1994. "Pressurized Groundwood (PGW) andSuper Pressurized Groundwood (PGW-S) Processes Produce Pulps of Almost Same StrengthProperties as TMP (Thermomechanical) Pulps Using Less Energy" in 7. 820R94005 International(Non-U.S.) Industrial Pollution Prevention: A Case Study Compendium, by O. o. W. U.S.Environmental Protection Agency (EPA). Washington, D.C.: EPA, pp. pp. 2-198--2-200.

Direct drying cylinder firing (pulp and paper)The pulp and paper industry is a large industrial energy user, with an estimated primary energy consumption of2,970 TBtu in 1994. In current drying practices, after the paper is formed and pressed and no more water can beremoved mechanically, the sheet moves through a series of 40-50 steam heated cylinders, with the final

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consistency being about 90-95% solids content. Direct drying/cylinder firing is a modification of the existingdrying process. Instead of heating the drying cylinders with steam, direct drying cylinder firing heats thecylinders using natural gas or other petroleum products, thereby reducing the intermediate step of steamproduction. The technology can achieve significant savings 0.95 MBtu/ton paper but does require additionaloperation and maintenance (Martin et al. 2000). A gas fired cylinder system was successfully installed atWillamette's No. 3 paper machine in Albany, Ore. The paper machine significantly improved efficiency andexperienced a 5% increase in overall drying capacity (Fleming, 1997). We estimate a savings potential of 45TBtu in 2015 based on the application of the technology to 10% of throughput.

Fleming, 1997. Linerboard Technology Developments Changing "Round and Brown" Image. Pulp and Paper.Volume 71, Issue 6.


Molten metal paper dryer (pulp and paper)The pulp and paper industry is a large industrial energy user, with an estimated primary energy consumption of2,970 TBtu in 1994. In current drying practices, after the paper is formed and pressed and no more water can beremoved mechanically, the sheet moves through a series of 40-50 steam heated cylinders, with the finalconsistency being about 90-95% solids content. The molten metal paper dryer is an alternative dryingtechnology being developed with support of the U.S. Department of Energy’s Office of Industrial Technologies.When the paper web comes into contact with a molten metal bath heat is transferred rapidly to the paper surfaceand boils off the water in the web. Because of its high surface tension the molten metal does not stick to thesurface of the paper as it exits the bath (OIT, 1999). Compared to other advanced drying technologies energysavings moderate (0.6 MBtu/ton paper), although capital investment costs are significantly lower (80%) thanconventional drying machines (OIT, 1999). Currently the technology has been tested at the laboratory level buthas not yet been developed on a commercial scale. We estimate potential savings at 10-20 TBtu in 2015.

OIT, 1999. “Molten Film Paper Dryer.” Project Fact Sheet.

Multi-port drying cylinder (pulp and paper)The pulp and paper industry is a large industrial energy user, with an estimated primary energy consumption of2,970 TBtu in 1994. In current drying practices, after the paper is formed and pressed and no more water can beremoved mechanically, the sheet moves through a series of 40-50 steam heated cylinders, with the finalconsistency being about 90-95% solids content. Argonne National Laboratory has been researching theopportunity to upgrade existing cylinder technology with the use of a multiport drying cylinder. The conceptinvolves the flow of steam through multiport passages that are in close proximity to the cylinder dryer surface,thereby achieving high drying rates than conventional cylinders by minimizing condensate formation andmaximizing heat transfer (OIT, 1998). In theory, the technology could increase the drying rate by 30%,although we did not locate data on the performance of the technology during its demonstration phase. Thetechnology is capable of being incorporated into existing machines. Applying an electricity savings of 10% to20% of paper production, we estimate a potential savings in 2015 of 15 TBtu.

OIT, 1998. “Design and Demonstration of Multiport Cylinder Dryers.”

Fluidized bed heat exchanger (pulp and paper)The pulp and paper industry is a large industrial energy user, with an estimated primary energy consumption of2,970 TBtu in 1994. Most of this energy is used to produce steam and electricity for process use. Steamefficiency measures can be highly cost-effective and many opportunities exist throughout a mill to improvesteam production and distribution efficiency such as boiler maintenance, improved process control, flue gas heatrecovery, steam trap maintenance and monitoring, and reusing hot condensate (Martin et al. 2000). A particularCADDET project identified was the use of newly developed fluidized bed heat exchangers that enabled thetransfer of heat from chip refiner exhausts to pre-heat white water used in the pulp manufacturing process.These particular heat exchangers were specially designed to be able to operate successfully in a highly corrosiveenvironment (see also Chemicals-3 “Heat Recovery in Harsh Environments” in the main report for additional

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information). Energy savings from the system were 0.3 MBtu/ton with a payback of less than two years. Weestimate savings of 10 TBtu in 2015.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1991. “Fluidisedbed heat exchangers in paperboard mill.”


New refractory materials-lime kiln (pulp and paper)The pulp and paper industry is a large industrial energy user, with an estimated primary energy consumption of2,970 TBtu in 1994. Within the industry, chemical pulping accounts for 77% of total pulp production andconsumes an estimated 300 TBtu of site energy (Martin et al. 2000). As part of the chemical recovery processcalcium carbonate precipitate is heated and converted to lime (CaO) in the lime kiln. The lime is then dissolvedin water to produce calcium hydroxide used in other parts of the chemical recovery process. Lime kilns areusually fueled by oil or gas and require an average of 2 MBtu/ton pulp of fuel and 13 kWh/ton electricity(Martin et al. 2000). Several modifications can improve the efficiency of lime kilns. One measure, theinstallation of high efficiency refractory insulation brick to reduce heat losses in the kiln. A U.S. Department ofEnergy, OIT, project identified a potential savings of 5% of the heat load with the use of a new hightemperature ceramic refractory. O&M costs would also be reduced since the refractory would last longer thanits conventional counterparts (OIT, 1999). DOE claims savings of nearly 23 TBtu were these refractorymaterials installed in all existing kilns in the U.S.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Monolithic Refractory Material”Martin, N.; Anglani, N.; Einstein, D.; Khrusch, M.; Worrell, E.; Price, L.K. 2000. Opportunities to Improve

energy Efficiency and Reduce Greenhouse Gas emissions in the U.S. Pulp and Paper Industry.Lawrence Berkeley National Laboratory. Report No. LBNL-46141.

Supercritical extraction and protein separation (textile)The food industry is dependent on energy to perform unit operations and processes. Because the food andkindred products industry is diverse, there are many types of operations. Energy-dependent processes preservefreshness and food safety. Thermal processing and dehydration are the most commonly used techniques forfood preservation. Process heating accounts for approximately 29.1 percent of total energy input in the foodindustry. It is also necessary to cool and refrigerate processed food to ensure safety and quality of the products.In the food industry sector, process cooling and refrigeration demand about 15.5 percent of total energy inputs(Okos, et al. 1998). Supercritical extraction and protein separation processes can save energy and reducewastewater formation in the food industry. This processing method can be used in the soy industries (for theextraction of soy protein) and the dairy industry (for the manufacture of casein).

Okos, M., N. Rao, S. Drescher, M. Rode, and J. Kozak. 1998. Energy Usage in the Food Industry. AmericanCouncil for an Energy-Efficient Economy, Washington D.C.

Suction slot dewatering (textile)Drying is the most energy-intensive process in the textile industry. A suction slot dewatering unit can beretrofitted to the top of the pad-mangle assembly and connected to a water separator and exhauster, thusincreasing production capacity by improved mechanical dewatering before drying (CADDET 1996). The slotface configuration comprises a single row of orifices in a herringbone pattern and does not give rise to anyproblems of stripes on the finished fabric. Two major advantages are established: rates of throughput of themain fabric types can be boosted considerably; and certain types of fabric can be effectively dewatered withoutfirst being passed through the mangle, eliminating many of the problems of fabric creasing. Other advantagesinclude the removal of loose fiber from the fabric and a more thorough impregnation of the material byfinishing chemicals. Mechanical dewatering uses less than ¼ the primary energy of thermal drying.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1996. “Suctionslot dewatering in textile finishing,” technical brochure.

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Direct contact water heating (textile)The textiles industry uses considerable quantities of steam for processing fabric. Traditionally, the steam issupplied from central boilers and distributed to the points of use. To reduce energy costs, direct contact waterheating involves converting dyeing and after- print processes to local direct gas firing, thereby moving towardsthe elimination of wasteful central boiler plants and steam distribution system. Natural gas-fired direct contactwater heater replaces the steam calorifier (CADDET 1991). This unit heats the water by a submerged, gas-firedimmersion tube and by direct contact with hot combustion gases. The heater is fully condensing and operates atan efficiency of about 93 percent. Substantial energy savings resulted from replacing heat generated in a centralboiler plant from interruptible gas, with heat generated local to the process from firm gas. Savings are realizedfrom the higher efficiency of direct-contact hot water generation (approximately 93 versus 82 percent), andreduced piping and reduced steam system losses.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1991. “DirectGas Firing Technology for Dyeing and After-Print Processing of Textile Fabrics,” technical brochure.

Textile heat recovery (textile)The installation of a boiler blowdown heat exchanger, a specialty boiler economizer, other energy conservationmeasures, and an extensive monitoring and control system can enable a textile facility to satisfy its needs forboiler steam during peak winter operation and conserve energy. The system also contributes to increased boilerefficiency. The heat exchanger recovers heat from the waste steam and transfers it to the cold water makeup tothe hot water system. The boiler economizer installed at National Spinning Company's textile plant inWashington, North Carolina also takes into account the particular needs of the facility (CADDET 1994). Theboiler economizer walls are lined with Teflon sheets. All exposed tubes have an extruded Teflon surface appliedfor corrosion protection. The economizer operates in parallel with the existing boilers. Stack gases are drawn offfrom the existing boiler stacks only when needed. The uses of these corrosion resistance coatings allow for lowapproach temperatures. This technology is applicable in many industries where steam systems are deployed.

[CADDET] Centre for the Analysis and Dissemination of Demonstrated Energy Technologies, 1994. “HeatRecovery System Saves Energy in a Textile Plant,” technical brochure.

———. 1989. “Filtration and Recycling of Stenter Exhaust in Textile finishing,” technical brochure.

Dyeing vacuum system (textile)See Suction Slot De-watering. These two technologies are so similar as to be identical.

Automated dyebath reuse technology (textile)The Georgia Institute of Technology (GIT) has developed an effective automated dyebath analysis and reusesystem that improves the energy, environmental, and economic performance of dyehouse batch operations. Thenew system enables dyeing solutions to be accurately monitored and adjusted for reuse. According to industryestimates, 160 pounds of water are used to produce each pound of textile product (OIT 1999). The currentwasteful batch dyeing process requires all water and residual chemicals, as well as the energy required to heatthe mixture for dyeing, to be dumped after one application. Spent dyebaths can only be reused after they aresampled, analyzed, and reconstituted, a process requiring labor and expertise unavailable in dyehouses.Therefore, successful commercial reuse depends on an automated analysis system that precisely analyzesdyebath samples in real-time and provides for reconstitution and reuse. If fully implemented throughout thecarpet industry, this innovation is expected to reduce energy consumption by 3.6 trillion Btu/year if the textileindustry uniformly adopts this technology by 2020. More likely, a market penetration of 10-15 percent wouldresult in 0.4 TBtu/year of savings. Waste and cost savings will also be substantial.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Dyebath Reuse in Carpet Manufacture,”project fact sheet. http://www.oit.doe.gov/nice3/pdfs/factsheets/GTRI.pdf

Membrane technology – textiles (textile)The textile industry continually strives to minimize pollution, particularly when dyeing cotton and cotton blendfabrics where a large amount of salts and color dye pollutants are discharged into water. The current processesto remove these pollutants from wastewater are difficult and costly. National Textiles, Inc., formerly Sara LeeKnit Products Corporation, uses a membrane technology in the dyeing process that recovers and reuses about 50

http://www.oit.doe.gov/nice3/pdfs/factsheets/GTRI.pdf

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percent of saltwater (brine) (OIT 1999). Use of a polymer needed for conventional color treatment is alsoeliminated. This technology significantly reduces the amount of colored wastewater generated and the need forassociated processing equipment. The overall volume of water to be treated is also significantly reduced. Thisvolume reduction dramatically downsizes the entire water treatment cycle, and also reduces capital equipmentexpenditures and associated maintenance costs. The energy required to transport salt will be cut in half, becauseof the reuse of the brine.

Office of Industrial Technology, U.S. Department of Energy, 1999. “Textile Brine Separation,” project factsheet. http://www.oit.doe.gov/nice3/projects/fctshts/texbrine.shtml

http://www.oit.doe.gov/nice3/projects/fctshts/texbrine.shtml

Documents

ACEEE_Emerging Indust EE Technologies_detail_Oct 2000