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Energy Efficiency and Innovative Emerging Technologies for Olefin Production
T. Ren
Utrecht University, The Netherlands
Email: [email protected], Heidelberglaan 2, 3584 CSSponsored by Utrecht Energy Research Center (UCE) and
Energy Research Foundation (ECN)
European Conference on Energy Efficiency
in IPPC-Installations
On October 21-22, 2004 in Vienna, Austria
Copernicus InstituteSustainable Development and Transition Management
In this presentation
• Introduction to olefins• Energy use and CO2 emissions• Energy analysis• State-of-the-art• Innovations• Conclusion• Next step
Where is the Olefin Industry?
IPTS 2000
Light olefins and Steam Cracking
Ethylene (C2H4) andPropylene (C3H6)
are two most important light olefins
They are the building blocksof the chemical industry.
Their production process, steam cracking,has the backbone status for the sector.
Used in the production of plastics, fibers, lubricants, films,textiles, pharmaceuticals, etc. ---even chewing gum!
Steam Cracking
BASF 2000
Energy Use and Emissionfrom Steam Cracking
• Steam cracking is the single most energy consuming processes in the chemical industry
ca. 30% of the sector’s total final energy useand ca. 180 millions tons of CO2 in 2004
Another reason for innovation:
over 35% of European crackers are over 25 years old
Estimated Global Energy Use and Emission 2004
World US
Europe (including new EU member states and FSU)
Total feedstock (Million tons)
300 85 90
Breakdown ofFeedstock (wt. %)
naphtha 55,ethane 30,LPG 10,gas oil 5
ethane 55,naphtha 23,propane15,
gas oil 5
naphtha 75,LPG 10,gas oil 9,ethane 5
Ethylene capacity (Million tons)
110-113 28-3030-32 (23-24 byWestern Europe)
Propylene capacity(Million tons)
53-55 16-17 17-18
Total process energy(fuel combustion and
utilitiesincluded) (EJ)
2-3 0.5-0.6 0.7-0.8
Total CO2 emission
(fuel combustion, decoking and utilities included)
(Million tons)
180-200 43-45 53-55
Conventional Naphtha-based Steam Cracking Process
IPPC/BREF 2001
A naphtha steam cracker (900 kt/a) at Shell Moerdijk, the Netherlands
Shell 2003
Energy/Exergy Analysis
Ethane Naphtha
Process Energy
Process Energy
Exergy loss
[27] [31] Ourestimate
[26][80][20]
Pyrolysis
Heat of reaction
23%65%
Fuel combustion and heat transfer to
the furnace75% (or 15 GJ/t
ethylene)
73%
N/ASteam,heating &losses
24%Heat exchange with
steam, TLEs and heat loss to flue gas
27%
Fractionation and Compression
22% 15% Fractionationf and Compression
25% (2 GJ/t
ethylene in
compression and the
rest of separation processes)
N/A
19%
Separation 31% 20%
De-methanization12%
De-ethanizer andC2 splitter
23%
C3 splitter2%
De-propanization/De-butanization
10%
Ethylene refrigeration
5%
Propylene refrigeration
30%
Total processenergy use
100% 100% Total exergy losses100% or 17 GJ/t ethylene
100% (only pyrolysis section)
100% (only compression
and separation)
Conclusions from Energy Analysis
• Pyrolysis section is the most energy consuming section (65% of the total energy use and 75% the total exergy losses)
• Also energy consuming (each ca. 15-20%):– Refrigeration and C2 separation– Fractionation and compression
State-of-the-Art Naphtha Steam Cracking Processes
Licensors Technip-Coflexip ABB Lummus Linde AG Stone & Webster Kellogg & Brown Root
Coil related furnacefeatures
Radiant coils pretreated to reduce coking with a sulfur-
silica mixture
Double pass radiant coil design; online decoking reduces
emissions
Twin-radiant-cell design (single split) is 13m (shorter than the average length
25m)
Twin-radiant-cell design and quadra-
cracking
Coil design (straight, small diameter), low
reaction time; very high severity
De-methanizerseparation
features
Doublede-methanizing stripping system
De-methanizer with low refrigeration
demand
Front-end de-methanizer and hydrogenation
De-methanization simultaneous mass transfer and heat
transfer
Absorption-based demethanization system
with front-end design
Gas TurbineN/a
Ca. 3 GJ/tethylene saved
N/a Offered but no data N/a
Ethylene Yield
(wt. %)35% 34.4% 35% N/a 38%
SEC(GJ/t
ethylene)
18.8-20 (best)or 21.6-25.2 (typical)
18 (with gas turbine);21 (typical)
21 (best) 20-25 No data
Conclusion: 20% of energy savings on the current energy use(25-30 GJ/t ethylene) of naphtha steam cracking are possible.
Advanced naphtha steam cracking
• Advanced furnace materials (e.g. low coking coating)
• Vacuum Swing Adsorption, mechanical vapor recompression
• Advanced distillation columns, membrane and combined refrigeration systems
• Conclusion: up to 20% energy savings are possible in the pyrolysis section and up to 15% energy savings are possible in the compression and separation sections.
Innovative Olefin Technologies
Gas Stream Technologies
Ethane Oxidative De-hydrogenation
Propane Oxidative
dehydrogenation
Catalytic cracking of
naphtha
Hydro-pyrolysis of
Naphtha
Byproduct upgrading(C4-9)
Catalytic Pyrolysis Process (CPP)
FeedEthane and other gas feedstock
Ethane and oxygen
Propane and oxygen
Naphtha Naphtha C4-C9 (from steam cracking, refinery, etc.)
Crude oil, refinery heavy oils, residues, atmospheric gas oil,
vacuum gas oil
Olefins Ethylene Ethylene PropyleneEthylene/propylene
Ethylene Propylene Ethylene/propylene
Reactor
Shockwave, combustion
gas; shift syngas;
plasma; etc.
Alloy Catalyst Reactor with
hydrogen co feed
Both a stem reformer and an
(oxy-reactor); or, cyclic fixed-bed
Fluidized bedReactors with hydrogen co feed but less
steam
Fixed or fluidized bedRiser and transfer line
reactor
CatalystN/a Mordenite zeolite
Zinc and calcium aluminate based
Zeolite (or various metal oxides)
N/a ZeoliteAcidic zeolite (Lewis
sites)
Temp. oC
625-700 900-1100 550-600 650-680 785-825 580-650 650-750
Process energy(SEC)i
Shockwave:ca. 8-10 GJ/t
ethylene/HVCs
Dow: ca. 10-12 GJ/t
ethylene/HVCs
Uhde: ca. 8-10 GJ/t propylene;
ca. 8-10 GJ/t HVCs
KRICT: ca. 19 GJ/t ethylene and ca. 10
GJ/t HVCs
Blachownia: ca. 16-20 GJ/t
ethylene andca. 10-13 GJ/t
HVCs
N/aCPP: ca. 35 GJ/t
ethylene and ca. 12 GJ/t HVCs
Yield (wt. %)j
Shockwave: highest
ethylene yield ca. 90%
Dow: final ethylene ca. 53%
if weighted against
ethane and oxygen
Uhde: propylene final yield ca.
78% if weighted against propane
and oxygen
KRICT: ethylene 38%, propylene
17-20%, aromatics 30% and HVCs
73%
Blachownia: Ethylene yield 36-40% and HVCs yield
70%
UOP: total propylene yield from steam
cracking is 30% and HVCs yield 85%
CPP: ethylene 21%, propylene 18%, C4
11%, aromatics 15% and
HVCs yield 60%
Currentstatus Lab Lab
Commercially available
Pilot plantCommercially
availableCommercially available
Lab and near commercialization
CHEEC Projectby Dow and SABIC (NL)
• CHEEC (Cheap Energy Efficient Ethylene Cracking)—catalytic olefin technology!
• Yield of ethylene and propylene together up by 24%
• Energy use reduced by 20%
• Investment lowered by 27% and variable costs lowered by 14%
Novem 2003
Conclusions from Innovative Olefin Technologies
• Catalytic olefin technologies produce high yield of valuable chemicals (in particular) propylene from low-cost feedstocks at lower reaction temperature
• Special reactors, catalysts or additional materials (oxygen, hydrogen, etc.) can be applied to reduce energy consumption
• Up to ca. 20% energy savings are possible (on 11-14 GJ/t high value chemicals of energy use by state-of-the-art naphtha steam cracking)
Overall Conclusions
• Pyrolysis section is the most energy consuming in a steam cracker
• Plenty of room for energy savings is possible in steam cracking
• Catalytic olefin technologies can lead to energy saving (up to 20%) on energy use by state-of-the-art steam cracking
Ca. 90% chemical processes already benefits from catalysis,so can steam cracking!
Our Next Step
• Energy and economic analysis for Natural gas-to-Olefin technologies have been completed—one conclusion is that at this moment there are no energy saving (75% more energy use and only feasible in locations where prices of natural gas are very low $0.75-1.0/GJ)
• Barriers/drivers and their implications for innovation in the (bulk) chemical industry are being studied
• Policies and strategies for stimulating innovation will be recommended
Thank you! Questions?
Some Backup SheetsWhy Do Catalytic Olefin Technologies Save Energy?
Progress of Cracking Process
Energ
y
Ethane, naphtha or other feedstocks
Olefins and byproducts
Activation Energywithout catalysts
Activation Energywith catalysts
Thermodynamicenergy requirement
Process energy required in a pyrolysis furnaceIn the case of conventional steam cracking
Process energy required in a reactorIn the case of catalytic olefin technologies
Energy saving!Ren 2003
Thermal Cracking
Naphtha
Free radicals
Reorganization
Ethylene Propylene
Simplified Chemical Reactions by ConventionalNaphtha Cracking (or Thermal Cracking)
Thermal cracking
Naphtha
Catalytic cracking
Free radicals
Zeolite Catalysts
Carbonium ions
etc.etc.
Reorganization
Ethylene Propylene
Simplified Chemical Reactions byCatalytic Naphtha Cracking
Drivers/Barriers (1/2)
• Economic Drivers
• Lower energy costs• Value added (from
low-cost feedstock to high value chemicals)
• Strong propylene demand
• Economic Barriers
• New plant investment in the range of 500 million to 1 billion euros
• Most old plants run with zero depreciation, low margins and over-capacity
Drivers/Barriers (2/2)
• Technical Drivers
• Rapid advances in R&D on new catalysts
• Spillover from extensive technical experience in refinery catalysts
• Technical Barriers
• Low olefin yield and high byproduct yield
• Reaction and oxygen use
• Coking and “spent catalysts”