Revised Appendix D System Descriptions - Plains Justice

Interstate Power and Light Company Addendum and Response to IDNR Sutherland Unit 4 Air Permit Application Requests for Additional Information

040308-145491

Revised Appendix D System Descriptions

SYSTEM DESCRIPTION FILE 145491.43.0201 NO.

BOTTOM ASH IP&L 030708-C

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1.0 System Description 1.1 System Identification

• Category Name Bottom Ash

• Category Code AS

• System Name Bottom Ash Handling

• System Code ASA

• File Number 43.0201

1.2 Function The Bottom Ash System collects and removes bottom ash from the bottom of the steam generator furnace. The system also collects coal pulverizer (pyrites) rejects and economizer ash. All are gathered in the upper trough of the Submerged Scraper Conveyor (SSC) and conveyed to a three walled ash storage bunker for periodic truck transport to a landfill. 1.3 Process Description A process flow diagram of the Bottom Ash Handling System for the generating unit is shown on drawing 145491-DS-S2105.

The Bottom Ash System for the generating unit will include the following major equipment and components:

• One submerged scraper conveyor (SSC) with rollout capability, outboard bearings, automatic lubrication system and chain washing system.

• One SSC recirculating water cooling and supply including: − One surge / settling tank. − Two recirculation pumps (one primary, one stand-by) − Two heat exchangers (one primary, one stand-by) − Two sludge return pumps (one primary, one stand-by) − One bunker sump pit − One bunker sump drain pump

• Five coal pulverizer rejects hoppers (one for each furnished coal pulverizer).

• Five coal pulverizer rejects jet pumps (one for each rejects hopper). • Two coal pulverizer rejects water sluice pumps (one primary, one stand-

by).



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• One economizer ash collecting dry drag chain conveyor • One double dump air lock valve • One transfer dry drag chain conveyor

1.3.1 Submerged Scraper Conveyor (SSC).

A mechanical system for collection, removal, dewatering and transport of bottom ash will be provided. The system will also provide for the removal and transport of economizer ash, coal pulverizer rejects and storage bunker drain effluent. Boiler seal plates, which extend below the SSC upper trough water level, will provide a pressure seal for the boiler. Bottom ash produced in the steam generator furnace will fall into the water-filled upper trough of the SSC. Economizer ash will be transferred via dry drag chain conveyors to the SSC outside of the seal plates. Rejects from the coal pulverizers will be sluiced to the SSC outside of the seal plates. The collected ash and coal pulverizer rejects in the upper trough of the SSC will be conveyed up a dewatering slope and discharged into a three-sided concrete storage bunker located indoors at the ground level, from where it will be loaded directly into ash dump trucks for off-site sales or transport to a landfill.

Water in the SSC upper trough will be maintained at a temperature of approximately 140°F or below. Water for controlling temperature and level in the SSC will be provided by one of two 100 percent capacity ash water recirculation pumps. The cooling system will be of a closed loop design. Water overflowing the SSC will be collected in a settling/surge tank. The ash water recirculation pumps will pump the hot overflow water through one of two 100 percent capacity heat exchangers before directing the water back to the upper trough of the SSC. The heat exchangers will be of a tube and shell design and will include backflush capability and an upstream strainer with backflush capability. To account for system water losses due to evaporation or retained water in the ash, a service water makeup connection will be provided to both the SSC and the settling/surge tank.

Sludge that collects in the settling/surge tank will be periodically pumped to the upper trough of the SSC via one of two 100 percent capacity sludge return pumps. Two chain flushing/cleaning nozzles will be provided at the top of the incline to remove ash accumulation from the chains prolonging chain and sprocket life. Sludge that collects in the ash bunker sump pit will be periodically pumped to the SSC recirculating water surge tank via one sludge drain pump.

. The SSC will also be equipped with the following features:



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• The entire SSC will be mounted on wheels and rolled on rails to permit full maintenance of the scraper conveyor and provide access to the bottom of the boiler during outages.

• The return trough of the SSC will be a wet bath arrangement to reduce scraper wear and resistance.

• The SSC will be designed so that the spilling of hot water or the ejection of the steam cannot endanger personnel.

• The tension take-up sprocket wheels will be located outside of the water filled hopper. A hydraulic chain tensioning device will be used as required to tension the chain. The tensioning device will not drift after tensioning of the chain. A mechanical or hydraulic position-locking device will ensure that drift does not occur.

• All maintenance parts of the SSC subject to abrasion and/or in contact with the ash (with the exception of the chain and sprocket wearing parts) will be fitted with readily replaceable wearing shoes or liners wherever practicable.

• The hydraulic drive unit of the SSC will enable bump less speed adjustment which will be infinitely variable between zero and maximum. The reduction gear connected by a flexible coupling will have an integrated overload trip to de-energize the motion in the event of any blockage to prevent overload damage to the drag link system and drive unit. The hydraulic drive will be selected to provide high torque at all operating speed conditions.

1.3.1.1 Sizing Criteria.

• The SSC will be able to contain an 8 hour backlog of material under normal boiler operating conditions as well as ash produced during a controlled boiler shut down when the downstream ash handling plant is unavailable. The SSC will be able to re-start with the load imposed by such a condition and be able to reclaim the backlog within 4 hours of operation.

• The SSC will also be designed with sufficient capacity to continuously remove all of the bottom ash, pyrites, and economizer ash generated by the boiler plus an additional 20 percent margin, when operating at MCR condition and burning fuel (from the selected design fuels) which results in the worst case (maximum) ash production.

• The speed and resultant conveying capacity of the SSC will be designed with an adjustable speed drive which will provide continuous removal under minimum and maximum load conditions, as well as for intermittent removal and backlog recovery under minimum and maximum load conditions. The maximum chain speed of the conveyor will not exceed 10 fpm.

• The SSC will be retractable during boiler outages. The height attained by the ash in the hopper will not impede the removal of the SSC after a controlled shutdown of the boiler, commenced after the 8 hour backlog period has expired.



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• All sprocket wheel bearings will be split type roller bearings suitably sized for an operating life without maintenance of 50,000 hours. Outboard bearing arrangements for all sprocket shafts will be provided.

• The concrete bottom ash load out bunker will be sized to temporarily store 4 days of bottom ash, economizer ash and pyrites produced by the boiler when operating at MCR condition and burning the design Performance fuel.

1.3.2 Pulverizer Mill Rejects (Pyrites) Collection and Transfer. The Bottom Ash System will also be designed to remove coal pulverizer rejects which represent 1.0 percent, by weight of the as-fired coal. During normal operation of the steam generator, each rejects hopper will continuously receive material rejected from the coal pulverizer. Material will accumulate in each rejects hopper until transferred to the SSC. During the transfer process, each coal pulverizer rejects jet pump will be operated in sequence to sluice the rejects from its respective hopper through a common transport line to the SSC. The rejects will enter the SSC at an enclosed area of the conveyor trough outside of the steam generator seal plates or as required to prevent splashing of water onto the lower boiler tubes. Each rejects hopper will be a self-supported steel tank mounted near the coal pulverizer rejects outlet and will be provided with a jet pump for intermittent hydraulic transfer of the rejects to the SSC. The coal pulverizer rejects system will also be designed for hopper unloading following a mill trip. Sluice water for transporting coal pulverizer rejects will be supplied from two sluice water pumps. One primary pump and one standby pump will be provided. The sluice water pumps will supply the required flow and pressure to the jet pumps to transport the coal pulverizer rejects from the hoppers to the SSC. The sluice water pumps will take their suction from the surge/settling tank. 1.3.2.1 Sizing Criteria.

• The pyrites collection hoppers will collectively be sized to store a minimum of 4 hours of pyrites from its associated coal pulverizer, when operating at MCR condition, and with one coal pulverizer out of service. The duration of sluicing time to cycle through and clear all of the hoppers will not exceed 30 minutes. For emergency purposes, the pyrites sluicing system will also be capable of clearing an individual coal pulverizer of all material within the time specified by the coal pulverizer manufacturer.

1.3.3 Economizer Ash Collection and Transfer. Economizer ash will continuously discharge from each economizer hopper into an enclosed dry drag chain conveyor system. Continuous removal of ash from the economizer hoppers will prevent sintering of ash in the hot gas stream which could result in pluggage of the hoppers. The system will consist of one collecting conveyor and one transfer conveyor. The collecting conveyor will dump onto the transfer conveyor through

SYSTEM DESCRIPTION FILE NO. 145491.43.0201


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a pneumatically actuated, electrically controlled double dump airlock valve. The transfer conveyor will transport the material to the upper trough of the SSC. A handwheel operated knifegate valve will be provided at the outlet of each economizer hopper to isolate the collecting conveyor from the hopper during maintenance or repairs. An air-electric automatic isolation valve will also be provided to isolate the collecting conveyor from the hoppers during normal operation of the system. An expansion joint shall be provided at each hopper to accommodate the axial and lateral movements of the hoppers. 1.3.3.1 Sizing Criteria.

• The economizer ash conveying system will be sized to convey four times the anticipated economizer ash production rate when operating at MCR condition and burning fuel (from the selected design fuels) which results in the worst case (maximum) ash production.

SYSTEM DESCRIPTION FILE 145491.43.0202NO.

FLY ASH HANDLING IP&L 030708-D

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• Category Name Fly Ash


• System Name Fly Ash Handling

• System Code ASB

• File Number 145491.43.0202

1.2 Function The Fly Ash Handling system is comprised of two separate systems. The Saleable Fly Ash Handling System removes fly ash from the ESP hoppers and transfers it to a saleable fly ash storage silo or a winter fly ash storage building via a continuously operating pneumatic vacuum and vacuum/pressure conveying system. The Waste Fly Ash Handling System removes fly ash from the fabric filter hoppers, air heater hoppers, and SCR hoppers and transfers it via a continuously operating pneumatic vacuum conveying system to a fly ash waste storage silo. The hopper fluidizing system for the fabric filter is not covered in this system definition. The saleable fly ash silo will be equipped with a silo bottom aeration system and fluidized outlet hopper. Fly ash from the saleable storage silo will be loaded into closed ash hauling trucks or railcars or conditioned and loaded into open dump trucks for placement in a landfill. A combination truck or rail scale capable of weighing both carriers will be provided for the saleable fly ash silo. The fly ash waste storage silo will be equipped with a silo bottom aeration system and fluidized outlet hopper. Fly ash from the waste storage silo will be loaded into closed ash hauling trucks or railcars or conditioned and loaded into open dump trucks for placement in a landfill. The winter fly ash storage building will be equipped with a pressurized conveying system to convey ash from the ESP vacuum filter/separator hopper to the building. A network of pressure conveying line branches will be provided to distribute saleable ash within the building. To recover the ash from the building, a recovery air gravity conveyor system will be provided to promote ash flow into a below grade recovery hopper. The recovery air gravity conveyor system will work in conjunction with a front end loader. A mechanical



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conveying system will transfer ash from the recovery hopper to a truck load-out system. A truck scale will be provided for the winter storage building truck load-out system. Dust collection and ash return equipment will be included to keep the building under negative pressure. 1.3 Process Description A process flow diagram of the Saleable Fly Ash Handling System is shown on drawing 145491-DS-S2103. A process flow diagram of the Waste Fly Ash Handling System is shown on drawing 145491-DS-S2104. The Fly Ash Handling System for the boiler unit will include the following major equipment and components. Vacuum and Pressure Conveying Systems:

• Five filter/separator assemblies to remove ash particles from the conveying stream. Two are provided for the saleable fly ash storage silo (one operating, one standby), two are provided for the fly ash waste storage silo (one operating, one standby), and one is provided for the winter storage building

• Four double dump airlock valves will be furnished between the filter/separators and the storage silos

• Manual hopper isolation valve and automatic ash intake valve under each ash collection hopper and an automatic branch isolation valve for each branch

• One pressure conveying airlock vessel under a filter/separator assembly to service the winter fly ash storage building

• Conveying pipe, fittings, diverters and valves designed for ash conveying applications

• Transport air pipe, fittings, and valves

Mechanical Exhausters / Fluidizing Blowers & Heaters: • Two 100% capacity fly ash transport mechanical exhauster assemblies

(one operating, one stand-by) for the saleable fly ash vacuum conveying system.

• Two 100% capacity waste fly ash transport mechanical exhauster assemblies (one operating, one stand-by) for the waste fly ash vacuum conveying system

• One 100% capacity pressure conveying blower for the winter storage building airlock conveyor



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• One 100% capacity air gravity conveyor fluidizing blower for winter storage building ash recovery conveyors

• Two full capacity saleable fly ash silo fluidizing air blowers (one operating, one stand-by).

• Two full capacity fly ash waste silo fluidizing air blowers (one operating, one stand-by).

• Four silo fluidizing blower air heaters (one operating, one stand-by) for the saleable fly ash silo and (one operating, one stand-by) for the fly ash waste silo

• Four ambient conveying air intake heaters and check valves (one operating, one standby) to heat the air entering the ESP conveying system and (one operating, one standby) to heat the air entering the fabric filter conveying system

Air Gravity Conveyor:

• Air gravity conveyors as required to recover fly ash stored in the winter storage building and convey to the fly ash recovery hopper inside the building

Saleable Fly Ash Silo / Fly Ash Waste Storage Silo / Winter Storage Building Unloading Systems:

• One saleable fly ash storage silo and associated equipment including high level switch, level transmitter and vacuum-pressure relief valve.

• One saleable fly ash storage silo fluidizing system • One saleable fly ash silo dry unloading system to load trucks and railcars,

complete with telescopic chute, vent fan, feed and vent piping, valves and control accessories

• Combination truck or railcar scale under the saleable fly ash silo discharge • Two fly ash silo ash conditioning systems, complete with two pugmill

unloaders (one operating; one stand-by), ash and water metering devices, isolation valves, instrumentation and control accessories

• One saleable fly ash storage silo bin vent • Two truck wash down sump pumps (one operating, one stand-by) • One fly ash waste storage silo and associated equipment including high

level switch, level transmitter and vacuum-pressure relief valve. • One fly ash waste storage silo fluidizing system • One fly ash waste silo dry unloading system to load trucks and railcars,

complete with telescopic chute, vent fan, feed and vent piping, valves and control accessories

• Two fly ash waste silo ash conditioning systems, complete with two pugmill unloaders (one operating; one stand-by), ash and water metering devices, isolation valves, instrumentation and control accessories

• One fly ash waste storage silo bin vent • Two truck wash down sump pumps (one operating, one stand-by)



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• One fly ash winter storage building with roll up door • Two winter storage building dust collectors with ID fans (both operating) • Two rotary feeders to meter fly ash from the winter storage building dust

collectors to the screw conveyors (one operating, one standby) • Two screw conveyors to return the winter storage building dust collector

ash to the building (one operating, one standby) • One winter storage building fly ash recovery hopper inside the building • One winter storage building screw conveyor to convey ash from the fly

ash recovery hopper to the bucket elevator • One winter storage building bucket elevator to convey ash to dry

unloading system truck load out • One winter storage building dry unloading system, complete with

telescopic chute, vent fan, feed and vent piping, valves and control accessories and support structure

• One truck scale for the saleable winter storage building truck load-out system

1.3.1 Saleable Fly Ash Conveying System The Saleable Fly Ash Handling System will service all unit ESP hoppers, one saleable fly ash storage silo and one fly ash winter storage building as shown in process flow diagram 145491-DS-S2103. Each collection point in the fly ash handling system will be tied into a pneumatic vacuum conveying system via ash intake valves arranged in a straight branch line off the main conveying lines. The conveying system will sequentially remove fly ash from the ESP hoppers and transfer the material to either the saleable fly ash storage silo or the winter storage building via a pressure conveying system. Each ESP hopper will be equipped with a manual hopper isolation valve and an automatic material intake valve. The automatic material intake valve isolates the hopper being emptied and provides a controlled flow of ash into the conveyor line. Each valve will be arranged for air-electric operation and will include replaceable, abrasion resistant components. Two vacuum filter/separators (2 X 100%) located on top of the saleable fly ash storage silo will receive and transfer the material to the saleable fly ash storage silo via a double dump airlock valves. A third vacuum filter/separator (1 x 100%) located at ground level next to the winter storage building will receive and transfer the ash into the winter storage building via a pressure pneumatic conveying system for future recovery into dry ash trucks. Each vacuum filter/separator on the saleable fly ash silo will consist of a continuous operating filter section with filter bags, pulse jet filter bag cleaning system, integral surge hopper and double dump airlock valve assembly for discharge into the silo. The vacuum filter/separator for the winter fly ash storage building will consist of a continuous operating filter section with filter bags, pulse jet filter bag cleaning system, integral surge hopper and a pressure airlock pneumatic conveyor to convey the ash to the



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winter storage building. Inside the building, a pressure conveying line will be provided with branches to direct the ash to various areas of the building. Each branch will be equipped with an automatic isolation valve. A dust detector will be furnished to detect broken filter bags and prevent intrusion of ash into the exhausters. Air intake heaters will be provided at the intake end of the ESP conveying line branches. Automatic vacuum breaker valves will also be furnished on the mechanical exhauster piping of each vacuum filter/separator. Two (2 X 100%) mechanical exhausters will be furnished for the vacuum conveying system. Each exhauster will be designed to supply motive air to convey the ash at the specified rate. One (1 X 100%) pressure blower will be furnished for the pressure conveying system to the winter storage building. The pressure blower will be designed to supply motive air to convey the ash at the specified rate. Two pneumatic conveying lines will convey material from the ESP branch lines to each filter/separator. The two conveying lines will be capable of transporting ash to the saleable fly ash storage silo or to the winter storage building pressure conveying/distribution system. One conveying line will be provided to convey material from the pressure airlock to the winter storage building including a distribution system with automatic valves to direct ash to various areas of the building. Branch segregating knife gate valves will be furnished on each branch line in the pneumatic conveying system. These valves will be of the automatic, abrasion resistant knife gate type, actuated by air cylinder operators. The conveying lines will be designed to maintain the air velocity above the material saltation velocity, minimize bends and provide adequate access for clearing out lines. The system will be able to start and stop conveying with ash in the conveying pipelines. All piping, elbows, laterals, and other fittings used on vacuum conveying pipelines will have minimum hardness ratings designed for ash conveying service. The saleable fly ash storage silo will be designed to receive and temporarily store saleable fly ash from the conveying system. The silo will have pass through access for ash discharge to railcars and trucks. The capacity of the silo will allow for up to four days of material storage based on the unit running at MCR conditions while burning worst case fuel. The saleable fly ash storage silo will be equipped with a fluidizing system to promote ash discharge during unloading. The silo will also include a bin vent filter, material level sensors and equipment access. The silo will be equipped with a dry fly ash load out station. This station will consist of discharge valves, telescopic chute assembly, vent fan, vent return valve, vent piping and pendant control. A combination truck or rail scale will be provided below the silo. 1.3.1.1 Sizing Criteria



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• The pneumatic vacuum and pressure conveying systems will be designed to continuously convey saleable fly ash from the ESP hopper outlets to either saleable fly ash storage location, at a net conveying rate equal to or exceeding 2.0 times the ash production rate from all ESP fly ash collection hoppers while operating the boiler at MCR condition and burning the highest ash content fuel. The overall conveying rate of the system will account for idle (non-conveying) time spent on startup, shut down, pipeline purges and indexing between hoppers and branch lines.

1.3.2 Waste Fly Ash Conveying System The Waste Fly Ash Handling System will service all unit fabric filter hoppers, all air heater hoppers, all SCR hoppers, and one fly ash waste storage silo as shown in process flow diagram 145491-DS-S2104. Each collection point in the waste fly ash handling system will be tied into a pneumatic vacuum conveying system via ash intake valves arranged in a straight branch line off the main conveying lines. The conveying system will sequentially remove fly ash from the hoppers and transfer the material to the fly ash waste storage silo. Each hopper will be equipped with a manual hopper isolation valve and an automatic material intake valve. The automatic material intake valve isolates the hopper being emptied and provides a controlled flow of ash into the conveyor line. Each valve will be arranged for air-electric operation and will include replaceable, abrasion resistant components. Two vacuum filter/separators (2 X 100%) located on top of the fly ash waste storage silo will receive and transfer the material to the fly ash waste storage silo via a double dump airlock valves. Each vacuum filter/separator on the fly ash waste silo will consist of a continuous operating filter section with filter bags, pulse jet filter bag cleaning system, integral surge hopper and double dump airlock valve assembly for discharge into the silo. A dust detector will be furnished to detect broken filter bags and prevent intrusion of ash into the exhausters. Air intake heaters will be provided at the intake end of each fabric filter conveying line branch. Automatic vacuum breaker valves will also be furnished on the mechanical exhauster piping of each vacuum filter/separator. Two (2 X 100%) mechanical exhausters will be furnished for the vacuum conveying system. Each exhauster will be designed to supply motive air to convey the ash at the specified rate. Two pneumatic conveying lines will convey material from the fabric filter branch lines to each filter/separator. Each row of fabric filter hoppers will have an independent conveying line. The two conveying lines will be capable of transporting ash to the fly ash waste storage silo.



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Pneumatic conveying lines will convey material from the air heater hoppers and SCR hoppers to each filter/separator. These conveying lines will tie into the conveying lines from the fabric filter. Branch segregating knife gate valves will be furnished on each branch line in the pneumatic conveying system. These valves will be of the automatic, abrasion resistant knife gate type, actuated by air cylinder operators. The conveying lines will be designed to maintain the air velocity above the material saltation velocity, minimize bends and provide adequate access for clearing out lines. The system will be able to start and stop conveying with ash in the conveying pipelines. All piping, elbows, laterals, and other fittings used on vacuum conveying pipelines will have minimum hardness ratings designed for ash conveying service. The fly ash waste storage silo will be designed to receive and temporarily store fly ash from the conveying system. The silo will have pass through access for ash discharge to trucks. The capacity of the silo will allow for up to four days of material storage based on the unit running at MCR conditions while burning worst case fuel. The fly ash waste storage silo will be equipped with a fluidizing system to promote ash discharge during unloading. The silo will also include a bin vent filter, material level sensors and equipment access. Ash conditioning pugmills (2 x 100%) will be provided as the primary means of ash unloading from the fly ash storage silo. Flow control valves will be provided to meter the ash and water into the pugmill. The silo will also be equipped with a dry fly ash load out station. This station will consist of discharge valves, telescopic chute assembly, vent fan, vent return valve, vent piping, and pendant control. 1.3.2.1 Sizing Criteria

• The pneumatic vacuum and pressure conveying systems will be designed to continuously convey fly ash from the fabric filter hopper outlets to the fly ash waste storage silo at a net conveying rate equal to or exceeding 2.0 times the ash production rate from all fly ash collection hoppers while operating the boiler at MCR condition and burning the highest ash content fuel. The overall conveying rate of the system will account for idle (non-conveying) time spent on startup, shut down, pipeline purges and indexing between hoppers and branch lines.

1.3.3 Saleable Fly Ash Storage Silo, Fluidizing System and Discharge System A saleable fly ash storage silo will be supplied to receive and temporarily store saleable fly ash from the vacuum conveying system. The capacity of the silo will allow for up to 4 days of saleable ash storage, including allowances for angle of repose and freeboard clearance, based on the unit running at MCR conditions while burning worst case fuel.



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The roof of the silo will be equipped with two filter/separators, a bin vent filter, a material level transmitter and material high level switches. A pressure/vacuum relief assembly will also be included on the roof. The silo will be arranged with parallel truck or railcar pass-through access and will include platforms at both the roof elevation and the unloading floor elevation. A single jib crane will be provided atop the silo. The silo will be of a flat-bottom design utilizing a floor fluidizing system to promote ash flow toward the silo discharge hopper(s) during unloading. The silo fluidizing system will consist of a network of floor fluidizer diffuser assemblies. The area of fluidizing coverage will be no less than 12 percent of the entire silo floor area. Fluidizing blowers (one operating, one standby), air heaters, piping, valves and flow control accessories will be furnished for the silo. Ash conditioning equipment will be provided as the primary means of ash unloading at the silo. Two ash conditioning pugmills (one operating, one standby) will be provided on the enclosed unloading floor under the silo. Manual and air cylinder operated valves will be provided to isolate the unloading equipment from the silo. An ash metering device (either automatic valve with positioner and feedback loop or rotary vane feeder) will control the flow of fly ash into the pugmill. A pressure regulating valve and flow meter will control the flow of water into the pug mill. To accommodate fly ash sales, the fly ash silo will be equipped with a dry load out station which consists of a telescopic chute assembly, silo isolation valve, automatic valve, vent fan, vent return valve, piping and a pendant control. The silo will also have pass through access with a combination truck or rail scale for weighed ash discharge to railcars or trucks. The silo unloading operation will be automated to the maximum practical extent. Local control stations will be provided to allow for the activation and control of the truck filling operation by the truck driver, including minor adjustments to ash/water feed rates.

The truck loading area beneath the silo will be equipped with wash down facilities. Truck wash down water will drain to a local saleable fly ash silo drainage sump. Water collected in the saleable fly ash silo drain sump will be periodically pumped to the waste water collection pond by one of two full capacity sump pumps (one operating, one standby). 1.3.3.1 Sizing Criteria

• The silo venting system will be sized to consider maximum flows from the following sources: (i) inflow from all fly ash pneumatic conveying systems; (ii) air introduced through silo floor fluidizing systems; (iii) air introduced from venting of silo unloading equipment; (iv) volume of expanded air (due to hot material entering silo). The filter inlet from the



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silo and dust return to the silo will be positioned far enough apart to minimize any dust re-entrainment.

• Each fly ash silo conditioning/unloading station will be capable of processing and unloading fly ash at a minimum rate of 270 tons per hour.

• The fly ash silo dry ash unloading station will be capable of unloading fly ash at a minimum rate of 180 tons per hour.

1.3.4 Fly Ash Waste Storage Silo, Fluidizing System and Discharge System A fly ash waste storage silo will be supplied to receive and temporarily store fly ash from the vacuum conveying system. The capacity of the silo will allow for up to 4 days of ash storage, including allowances for angle of repose and freeboard clearance, based on the unit running at MCR conditions while burning worst case fuel. The roof of the silo will be equipped with two filter/separators, a bin vent filter, a material level transmitter and material high level switches. A pressure/vacuum relief assembly hatch will also be included on the roof. The silo will be arranged with parallel truck pass-through access and will include platforms at both the roof elevation and the unloading floor elevation. A single jib crane will be provided atop the silo. The silo will be of a flat-bottom design utilizing a floor fluidizing system to promote ash flow toward the silo discharge hopper(s) during unloading. The silo fluidizing system will consist of a network of floor fluidizer diffuser assemblies. The area of fluidizing coverage will be no less than 12 percent of the entire silo floor area. Fluidizing blowers (one operating, one standby), air heaters, piping, valves and flow control accessories will be furnished for the silo. Ash conditioning equipment will be provided as the primary means of ash unloading at the waste silo. Two ash conditioning pugmills (one operating, one standby) will be provided on the enclosed unloading floor under the silo. Manual and air cylinder operated valves will be provided to isolate the unloading equipment from the silo. An ash metering device (either automatic valve with positioner and feedback loop or rotary vane feeder) will control the flow of fly ash into the pugmill. A pressure regulating valve and flow meter will control the flow of water into the pug mill. The fly ash waste silo will also be equipped with a dry load out station which consists of a telescopic chute assembly, silo isolation valve, automatic valve, vent fan, vent return valve, piping and a pendant control. The waste silo unloading operations (both dry and conditioned fly ash) will be automated to the maximum practical extent. Local control stations will be provided to allow for the activation and control of the truck filling operation by the truck driver, including minor adjustments to ash/water feed rates.



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The truck loading area beneath the silo will be equipped with wash down facilities. Truck wash down water will drain to a local fly ash waste silo drainage sump. Water collected in the fly ash waste silo drain sump will be periodically pumped to the waste water collection pond by one of two full capacity sump pumps (one operating, one standby). 1.3.4.1 Sizing Criteria

• The silo venting system will be sized to consider maximum flows from the following sources: (i) inflow from all fly ash pneumatic conveying systems; (ii) air introduced through silo floor fluidizing systems; (iii) air introduced from venting of silo unloading equipment; (iv) volume of expanded air (due to hot material entering silo). The filter inlet from the silo and dust return to the silo will be positioned far enough apart to minimize any dust re-entrainment.

• Each fly ash waste silo conditioning/unloading station (two each silo) will be capable of processing and unloading fly ash at a minimum rate of 270 tons per hour.

• The fly ash waste silo dry ash unloading station will be capable of unloading fly ash at a minimum rate of 180 tons per hour.

1.3.5 Fly Ash Winter Storage Building, Fluidizing System and Load-out System A winter storage building will be supplied to receive and temporarily store saleable fly ash from the ESP vacuum/pressure conveying system. The fly ash storage capacity of the building will be 30,000 tons. The building will be constructed of a concrete base, concrete partial wall, structural steel frame, steel wall panels and steel roof panel sections. Access and platforms will be provided for maintenance of equipment inside the building. Access doors for front end loading equipment will be provided. To fill the building, one vacuum filter/separator located at ground level will receive ash from the ESP hoppers and discharge it through a pressure airlock into a pressure conveying line with multiple branches to distribute the ash within the building. Each branch will be equipped with an automatic isolation valve. Two dust collectors with ID fans will be provided to pull dust laden air from inside the building and exhaust the filtered air to atmosphere. The dust collector will maintain the building under a slight negative pressure. A rotary airlock and screw conveyor will be provided at the discharge of the dust collector hopper to convey accumulated dust back into the building.



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To remove the ash from the building an air gravity conveyor will be supplied at floor level to promote ash flow into an ash recovery hopper in conjunction with a front end loader. Ash collected in the recovery hopper will be conveyed by screw conveyor to the truck load-out area. The screw conveyor will discharge into a bucket elevator which will convey the material up into a dry load out station positioned over a truck drive-through. The load-out station consists of a telescopic chute assembly, automatic isolation valve, vent return valve, piping to the building dust collector system and a pendant control. A truck scale for the truck load-out system will also be provided. 1.3.5.1 Sizing Criteria

• The building venting system will be sized to consider maximum flows from the following sources: (i) inflow from all fly ash pneumatic conveying systems; (ii) air introduced from venting of truck load-out equipment; (iii) volume of expanded air due to hot material entering the building.

• The fly ash building dry ash unloading station will be sized to load fly ash into trucks at a minimum rate of 180 tons per hour or the maximum front end loader feed rate into the recovery hopper.


FGD SOLIDS IP&L 030708-C

0205-1

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• Category Name Bulk Material (Other Than Coal)


• System Name FGD Solids

• System Code ASE


1.2 Function This document provides basic function and description for the solids material handling of the flue gas desulfurization (FGD) addition. The function of the Flue Gas Desulfurization (FGD) Solids System is to collect and dewater the solids produced within the Flue Gas Desulfurization System, and transport the dewatered solids to a stock pile. The FGD solids produced will be transported to the landfill. 1.3 Process Description The following process flow diagrams will describe the material flow and various processes used in the FGD Solids system. Drawing No. Description 145491-1ASE-M2025A Flow Diagram FGD Solids 145491-1ASE-M2025B Flow Diagram FGD Solids 145491-DS-S2106 Flow Diagram FGD Solids The FGD Solids System will consist of the following major components.

• FGD solids product conveyors, CVY-1A and CVY-1B • Associated piping, valves, instruments, controls, and accessories

The dewatered FGD solids will be removed from the vacuum filters by a set of belt conveyors and diverter gates. Each vacuum filter will be sized to process the maximum byproduct gypsum production corresponding to 24 hours of operation at maximum continuous rating (MCR) in a 24-hour period.


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1.3.1 System Operation. There will be two 100 percent FGD Solids System trains housed in a common building. The dewatered FGD solids will be discharged from the vacuum filters onto one of the two FGD solids product conveyors CVY-1A or CVY-1B through motorized diverter gates GAT-1A and GAT-1B. Conveyors CVY-1A and CVY-1B will transfer the solids to a conical pile. The FGD solids from the stock pile will be loaded onto trucks by mobile equipment (and transported to the landfill). In order to prevent fine solids from accumulating in the FGD recycle tanks, a small flow stream will be taken from the hydrocyclone classifier overflow to be blown down to a local drain sump that will be equipped with an agitator to keep the solids in suspension and to be removed later using sump pumps that will transfer the sump water to the Wastewater Collection and Treatment System. Classifiers will be capable of being backflushed or serviced on line to remove any pluggage that occurs.


BIOMASS HANDLING SYSTEM IP&L 030708-A

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• Category Name Bulk Materials (Other Than Coal)

• Category Code BM

• System Name Biomass Handling System

• System Code BMU


1.2 Function The biomass handling system will provide the necessary functions to receive, process, and convey the processed biomass to the boiler. The design and process described herein are based on the principles and extensive operating experience derived from the biomass fuel operations at IPL’s Ottumwa Generating Station. 1.3 Process Description Drawing 145491-DS-S2102 is the process flow diagram of the Biomass Handling System. The Biomass Receiving, Storage and Reclaim System will include the following major equipment and components:

• Two Chain Conveyors, CVY-1A & CVY-1B, 12.5 TPH • Two Destringers • Two Debalers • Two Belt Conveyors, CVY-2A & CVY-2B, 60” 12.5 TPH (each) • Two Belt Scales, SCL-1 & SCL-2 • Two Inline Magnetic Separators, SEP-1 & SEP-2 • Two Shredders • Two Primary Collectors • Two Secondary Collectors • Two Exhaust Fans, FAN-1A & FAN-1B • Two Belt Conveyors, CVY-3A & CVY-3B • Two Metering Bins • Four Screw Conveyors


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• Four Boiler Feed Blowers • Eight Rotary Feeders

1.3.1 System Operation: The biomass fuel is harvested into “bales” which are of approximate dimensions 3 ft by 4 ft by 8 ft (which weigh approximately 1,000 pounds). The bales will be delivered to the site on flatbed trailers with 42 (3 ft by 4 ft by 8 ft) bales on each trailer. The bales will then be unloaded with an overhead crane and either stacked in the storage building or immediately into the processing cycle. The bales will be picked up with the overhead crane or mobile equipment and placed onto Chain Conveyor CVY-1A or CVY-1B. There are two identical processing lines denoted by equipment callout “A” and “B”. The binding twine will automatically be cut and retrieved from the bale by a “Destringer” prior to the bale feeding into the “Debaler”, a hammermill, which will mill the biomass. The biomass will be collected and conveyed by Belt Conveyors CVY-2A or CVY-2B to one of two “Shredders”, an attrition mill, configured to reduce the biomass to the selected size for pneumatic conveying to the boiler. Prior to the biomass reaching the attrition mill, Inline Magnetic Separator SEP-1 and SEP-2, will collect all foreign metal objects captured during the baling process. Belt Scale SCL-1 and SCL-2 will be located on CVY-2A and CVY-2B respectively, to monitor feed rate. At the discharge of the “Shredder” is a stone trap which is a lowered section in the duct work where rocks or other heavy non-metallic objects can fall out of the air stream to avoid being sent to the boiler. A baghouse and separator, Secondary Collector 1A and 1B, will pull the biomass material from the discharges of the “Shredders”, where the heavy material will drop down into the Primary Collectors, and the lighter material will move into the baghouses for collection. The Primary Collectors will discharge into Metering Bins by means of Rotary Feeders. The lighter biomass material will then be removed from the baghouse and feed onto covered Belt Conveyor CVY-3A and CVY-3B by means of rotary feeders. Belt Conveyors CVY-3A and CVY-3B will convey the biomass material to the Metering Bins for pneumatic transport to the boiler. All of the equipment downstream of the shredder will be kept at a slight negative pressure for dust control. A vacuum system will be installed to help keep the building and equipment free of fugitive biomass. This system will discharge into the Primary Collectors.


LIMESTONE HANDLING SYSTEM IP&L 030708-C

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• Category Name Bulk Materials (Other Than Coal)

• Category Code BM

• System Name Limestone Handling System

• System Code BMU


1.2 Function The function of the Limestone Handling System will be to receive bulk limestone by truck, store the limestone in an active and long-term storage pile, and to provide reclaim capacity to satisfy plant usage requirements. 1.3 Process Description Drawing 145491-DS-S2101 is the process flow diagram of the Limestone Handling System. The Limestone Receiving, Storage and Reclaim System will include the following major equipment and components:

• Limestone Storage Building • Two Stamler Feeders with Breakers 0-200 TPH (each), FDR-1 & FDR-2 • Dust Suppression System located at discharge of Stamler Feeders • One Reclaim Conveyor, CVY-1 – 24”, 200 TPH • One Belt Scale SCL-1 on Reclaim Conveyor CVY-1 • One Inline Magnetic Separator SEP-1 at head end of CVY-1 • One, 2-way motorized flop gate, GAT-1 • One Distribution Conveyor, CVY-2 – 24”, 200 TPH • Two Limestone Silos – 1 day (450 tons) each • One Limestone Dust Collection System DCO-1

1.3.1 System Operation: Bulk limestone will be delivered by dump trucks and formed into an active and inactive pile by mobile equipment (by others). The inactive pile will provide 45 days of storage. The active pile will have a total capacity of 2,688 tons equivalent to 7-days use for unit 4.



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The active pile will be protected by a covered steel structure to protect the limestone from the weather. The reclaim process begins with mobile equipment (by others) pushing/dumping the limestone onto two Stamler Feeders, FDR-1 and FDR-2, equipped with breakers. Each Stamler Feeder will reclaim the limestone at 0-200 TPH and discharge onto Reclaim Conveyor CVY-1, 24” 200 TPH. Reclaim Conveyor CVY-1 is equipped with Belt Scale SCL-1 used for feed control and inline Magnet Separator SEP-1 located at the head end. The Reclaim Conveyor CVY-1 will discharge the limestone into a 2-way motorized flop gate, GAT-1. One leg of this chute will be used to fill Limestone Silo 1, and the other leg will transfer the limestone to the Distribution Conveyor CVY-2, 24” 200 TPH. Distribution Conveyor CVY-2 will discharge to Limestone Silo 2. Limestone Dust Collection System DCO-1 will provide dust control for the Limestone Processing Building. The limestone reclaiming and silo fill system will operate as needed basis, to fill the limestone silos. During the operation of the limestone mills, a silo low level alarm will trigger an operator controlled start function of the reclaim and silo fill system. The operators will be able to regulate the speed of the Stamler Feeders with the help of in-line belt scale mounted on Reclaim Conveyor CVY-1. An inline magnetic separator mounted at the head/discharge section of Reclaim Conveyor CVY-1 will be able to remove the harmful ferrous metal objects from the limestone flow before they reach the silos or the mills. Suitably designed dust control equipment will be installed at strategic locations of the system. The limestone dust control system will control the escape to atmosphere of dust particles generated at the various transfer locations in the limestone handling system. A spray type dust suppression system will be provided at the discharge of the Stamler Feeders. A fabric filter bag type dust collector will be provided at the silo fill area. 1.3.2 Equipment Description: Belt Conveyors. The conveyor subcomponents include the conveyor belt, idlers, pulleys, take-ups, bearings, belt cleaners, drives, motors, drive base-plates, walkways, stringers, supports, head and tail frames, foundations, and all other appurtenances necessary for each of the individual conveyors. Reclaim Conveyor CVY-1 will have full conveyor hoods and wind guard. A walkway on one side of the Reclaim Conveyor CVY-1 will be furnished. Stamler Feeders. The function of the Stamler Feeders will be to reclaim the limestone and discharge onto limestone reclaim conveyor at the desired rate. They include breakers which will prevent any large lumps of limestone from damaging the belt conveyor.



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Magnetic Separator. The magnetic separator will be the overhead, self-cleaning, belted in-line, fluid-filled type. The magnetic separator will be housed completely inside dust covers. The magnetic separator will be mounted at the head chute of conveyor CVY-1. The magnetic separator will be positioned above and forward of the conveyor head pulley. The magnet will be sloped towards a tramp iron chute. The tramp iron chute will transport tramp iron to a collection box at grade. Belt Scales. Conveyor CVY-1 will be provided with a belt scale. The primary function of the belt scale is for feed rate control and material inventory monitoring. The belt scale will be the 3 or 4-idler precision digital electronic type with solid-state circuitry and built-in, self-testing devices. The scale will also be provided with test weights for self calibration. Each belt scale will use an environmentally sealed, temperature-compensated, load-sensing device and weigh bridge. The scale will weigh and totalize to a value within 1 to 2% of the test load at flow rates between 25% and 100% of the scale system’s calibrated capacity. Limestone Storage Building. The limestone storage building will protect the 7-day storage pile. The building will have open sides and a roof to prevent the escape of limestone dust and to protect the pile from weather. The storage building will be constructed from steel columns and beams and provided with girts, purlins and bracing. The roof will be of non-insulating metal panel construction. Dust Control. The purpose of the limestone dust control equipment is to minimize the escape of fugitive limestone dust into the atmosphere from the limestone reclaim operations. Two types of dust control equipment will be used, dry dust collection and wet dust suppression.

1. Dry dust collection systems- DCO-1:

In general, the dust collector will be induced draft filter bag unit, enclosed in stiffened plate housing and supported on wide flange column legs. Dust-laden air will be directed to the inlet plenum at the dust collector unit through ductwork. After passing through the filter bags, the filtered air will be drawn from the unit by induced draft fan and discharged to the atmosphere.

Dust collected by the filter bags, as well as dust precipitated within the unit, will fall in hoppers which will form the unit housing bottom. A rotary vane type air lock valve will be furnished at each point where hopper-collected dust is to be transferred from the vacuum condition in the collectors to an atmospheric/pressure region.

2. Wet dust suppression systems- Reclaim Area:



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The dry fog dust suppression systems uses a mixture of water and a proprietary chemical solution, in combination with high pressure air mixed vigorously to form a light spray, fog, which will be sprayed through nozzles into spaces inside the conveyor transfer chutes and skirt board areas. The spray captures the fugitive limestone dust and the heavier particles fall back into the limestone stream. The spray type dust suppression system uses a mixture of water and a proprietary chemical solution, or just water, which is pumped directly to spray nozzles that provide a heavier water stream than the dry fog nozzles. The spray type dust suppression system will be used at the discharge of the telescopic chute. Each dust suppression system will consist of a pump skid which will mix the water and the chemical in the desired proportion in combination with compressed air. This mixture will then be pumped to the nozzle headers mounted on the limestone handling equipment. Each pump skid will be enclosed in an insulated and heated enclosure or in an enclosed and heated building. Piping for dust suppression systems will be heat traced where exposed and will be arranged to drain to a system low point.


COAL HANDLING SYSTEM IP&L 030708-C

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• Category Name Coal Handling

• Category Code CH

• System Name Coal Handling System

• System Code CHU


1.2 Function The function of the Coal Handling System will be to receive and unload coal delivered by rail cars, provide a means to stock out and store the coal in active and reserve storage piles, provide the means to reclaim, blend, crush the coal to the desired size, and supply the coal to the Unit 4 silos to satisfy plant usage requirements. The coal handling system will also be sized to serve existing Units 1, 2, and 3 by providing a separate stockout facility to store coal unloaded by the Unit 4 unloading facility and to provide a separate reclaim facility to reclaim coal designated for Units 1, 2, and 3. 1.3 Process Description Drawing 145491-DS-S2100 is the process flow diagram of the Coal Handling System. 1.3.1 System Components The Coal Handling System will include the following major equipment and components:

• Rail Car Positioner • Rotary Car Dumper- DMP-1 • Rotary Car Dumper Dust Collection System, DCO-1 to control dust in the

dumper building • Coal Unloading Hopper, HPR-1, with four outlets each equipped with a

manual isolation gate and a traveling hammermill for oversize and frozen coal breaking

• Belt feeders, FDR-1 & FDR-2 under unloading hopper outlets • Belt conveyor CVY-1 - 72”, 4000 TPH coal receiving with a 2-way flop gate

at discharge • Belt Scale SCL-1 on Belt conveyor CVY-1, ¼ % accuracy for received coal

weighing



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• As-Received Sweep Sampling System SAM-1, on Belt Conveyor CVY-1 • Inline Magnetic Separator SEP-1 at the head end of CVY-1 • Transfer Tower TT-1 Dust Collection System, DCO-2 • Belt Conveyor “Stockout Conveyor” - 72”, 4000 TPH emergency stock out

conveyor • Telescopic chute, at Belt Conveyor “Stockout Conveyor” discharge • Dust Suppression System DS-1 at “Stockout Conveyor” discharge • Belt Conveyor CVY-2 – 72”, 4000 TPH stacking/reclaiming yard conveyor,

with a 2 position movable head • Stacker/Reclaimer SKR-1 with 72” boom conveyor capable of 4000 TPH

stacking and 600 or 1200 TPH reclaim • Dust Suppression System DS-2 for stacking/reclaiming operations • Belt Scale SCL-2 on Belt Conveyor CVY-2, ½ % accuracy for coal for coal

blending reclaim and/or feed rate control • Surge Hopper, HPR-3A, with a single outlet equipped with manual isolation

gate • Surge Hopper, HPR-3, with dual outlets each equipped with manual isolation

gate • Variable Frequency Drive Belt Feeder 0-400 TPH, FDR-4, below Surge

Hopper HPR-3A • Variable Frequency Drive Belt Feeders 0-660 TPH (each), FDR-5 & FDR-6,

below Surge Hopper HPR-3 • Transfer Tower TT-2 Dust Collection System, DCO-3 • Reclaim Hopper, HPR-2, with manual isolation gate • Variable Frequency Drive Belt Feeder 0-660 TPH, FDR-3, below Reclaim

Hopper HPR-2 • Reclaim tunnel Dust Collection System, DCO-4 • Belt Conveyor CVY-3 – 36”, 660 TPH with a 3 position movable head • Belt Scale SCL-3 on Belt Conveyor CVY-3, ½ % accuracy for coal blending

reclaim and/or feed rate control • Belt Conveyor CVY-4 – 36”, 660 TPH • Belt Conveyor CVY-5 – 36”, 660 TPH • Belt Scale SCL-4 on Belt Conveyor CVY-4, ½ % accuracy for as-fired coal

weighing and/or feed rate control • Belt Scale SCL-5 on Belt Conveyor CVY-5, ½ % accuracy for as-fired coal

weighing and/or feed rate control • Inline Magnetic Separator SEP-2 at the head end of CVY-4 • Inline Magnetic Separator SEP-3 at the head end of CVY-5 • Crusher Surge Hopper, HPR-4, with dual outlets each equipped with a manual

isolation gate • Variable Frequency Drive Belt Feeders 0-660 TPH (each), FDR-7 & FDR-8,

below Crusher Surge Hopper • Crusher CR-1, 660 TPH ring granulator • Crusher CR-2, 660 TPH ring granulator



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• Crusher House CH-1 Dust Collection System, DCO-5 • Belt Conveyor CVY-6 – 36”, 660 TPH with a 3-way flop gate at discharge • Belt Conveyor CVY-7 – 36”, 660 TPH with a 3-way flop gate at discharge • Tramp Metal Detector TMD-1, on Belt Conveyor CVY-6 • Tramp Metal Detector TMD-2, on Belt Conveyor CVY-7 • As-Fired Sweep Sampling System SAM-2, serving Belt Conveyors CVY-6 &

CVY-7 • Transfer Tower TT-3 and Unit 4 Silos Dust Collection System, DCO-6 • Reversing Belt Conveyor CVY-8 – 42”, 660 TPH • Reversing Belt Conveyor CVY-9 – 42”, 660 TPH • Belt Conveyor CVY-10 – 30”, 400 TPH • Stamler Feeder with Breaker 0-400 TPH, FDR-9 • Dust Suppression System DS-3 for Stamler Feeder • Belt Conveyor CVY-11 – 30”, 400 TPH • Transfer Tower TT-4 Dust Collection System DCO-7 • Belt Conveyor CVY-12 – 30”, 400 TPH • Belt Scale SCL-6 on Belt Conveyor CVY-12, ½ % accuracy for feed rate

control • Inline Magnetic Separator SEP-4 at the head end of CVY-12 • Transfer Tower TT-5 Dust Collection System DCO-8 • Belt Conveyor CVY-13 – 30”, 400 TPH with a 2-way flop gate at discharge • Surge Hopper, HPR-5, with motor operated outlet gate, side dump chute, and

motor operated side dump chute slide gate • Surge Hopper, HPR-6, with manual isolation gate • Variable Frequency Drive Belt Feeder 0-200 TPH, FDR-10, below Surge

Hopper HPR-6 • Dust Collection System DCO-9 for Existing Transfer Tower • Truck Loadout Chute and Enclosure • Dust Collection System DCO-10 for Truck Loadout Enclosure

1.3.2 System Operation. The new coal handling system at the Sutherland Plant will supply coal to the existing Units 1, 2, and 3 as well as the new Unit 4. The burn rate of units is as follows: Unit 1 15 TPH Unit 2 15 TPH Unit 3 45 TPH Unit 4 383 TPH



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The recommended coal storage capacities are as follows: Active Storage – 5 Days Reserve Storage – 45 Days Unit 1 1,800 Tons Unit 1 16,200 Tons Unit 2 1,800 Tons Unit 2 16,200 Tons Unit 3 5,400 Tons Unit 3 48,600 Tons Unit 4 45,960 Tons Unit 4 413,640 Tons The system will be designed to accommodate simultaneous car unloading, stacking and silo fill operations to Units 4 and be configured to provide sufficient redundancy for non-operating equipment. Coal will be delivered to the power plant by unit train consisting of approximately 150 cars. Each of the rail cars will carry approximately 120 tons of coal. The coal received in the plant will be unloaded by a rotary car dumper at a rate of 4,000 TPH. The rotary car dumper will be equipped with a rail car positioner, hopper, grizzly and traveling hammermill for the breaking of oversize and frozen coal. The unloaded coal will be collected by the hopper and withdrawn by two belt feeders FDR-1 and FDR-2. Dust Collection System DCO-1 will control dust in the dumper building. The coal will be transferred from the feeders to unloading conveyor CVY-1, 72” 4000 TPH, which will take it to Transfer Tower TT-1. Belt conveyor CVY-1 will be equipped with the as-received sampling system SAM-1 and Belt Scale SCL-1. The discharge of conveyor CVY-1 will be equipped with inline Magnetic Separator SEP-1 and a 2-way motorized flop gate. Dust Collection System DCO-2 will provide dust control in Transfer Tower TT-1. At Transfer Tower TT-1, the coal would be directed to Belt Conveyor CVY-2 which feeds Stacker/Reclaimer SKR-1. Belt Conveyor CVY-2, 72” 4000 TPH, will be equipped with Belt Scale SCL-2 and a 2 position movable head. Under normal operating conditions the unloaded coal will be stacked out by Stacker/Reclaimer SKR-1 at 4,000 TPH. During reclaiming the boom conveyor of Stacker/Reclaimer SKR-1 will be reversed to support a reclaim capacity of either 1,200 TPH or 600 TPH onto Belt Conveyor CVY-2. The discharge point at the top of Stacker/Reclaimer SKR-1 will be equipped with a motorized flow splitting gate, enabling the operator to split the material flow of 4,000 TPH into two separate streams, one stream would be sent directly to crushing and silo fill and the second stream going to stockout. Dust Suppression System DS-2 will control dust for these transfer points. In case of a Stacker/Reclaimer SKR-1 failure, the unloaded coal will be stacked out at 4000 TPH by emergency stacking conveyor “Stockout Conveyor”, equipped with telescopic chute and Dust Suppression System DS-1 onto an emergency pile. Depending on operating requirements, the coal from the emergency pile may be bulldozed directly into the yard storage or to the reclaim hopper HPR-2, equipped with a Variable Frequency Drive Belt Feeder FDR-3 at a rate of 0–660 TPH, and fed onto Belt



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Conveyor CVY-3. Belt Conveyor CVY-3 will be 36”, 660 TPH and will be equipped with Belt Scale SCL-3 and a 3 position movable head. Dust Collection System DCO-4 will provide dust control in the reclaim tunnel. Belt Conveyor CVY-3 will discharge to Belt Conveyor CVY-10, Belt Conveyor CVY-4, or Belt Conveyor CVY-5 in Transfer Tower TT-2. Belt Conveyor CVY-2 will discharge into Surge Hopper HPR-3 or HPR-3A in Transfer Tower TT-2. Dust Collection System DCO-3 will provide dust control in Transfer Tower TT-2. Surge Hopper HPR-3A, equipped with a rack & pinion slide gate, discharges with a Variable Frequency Drive Belt Feeder FDR-4 at a rate from 0-400 TPH onto Belt Conveyor CVY-10, 30” 400 TPH. Surge Hopper HPR-3 has dual outlets each equipped with a rack & pinion slide gate and a Variable Frequency Drive Belt Feeder FDR-5 and FDR-6 capable of 0-660 TPH (each). Feeders FDR-5 and FDR-6 discharge on to Belt Conveyor CVY-4 and CVY-5 respectively. Belt Conveyor CVY-4, 36” 660 TPH, will be equipped with Belt Scale SCL-4. The discharge of CVY-4 will be equipped with inline Magnetic Separator SEP-2. Belt Conveyor CVY-5, 36” 660 TPH, will be equipped with Belt Scale SCL-5. The discharge of CVY-5 will be equipped with inline Magnetic Separator SEP-3. Coal from Belt Conveyor CVY-4 and CVY-5 will discharge into Surge Hopper HPR-4 located inside the Crusher House CH-1. Dust Collection System DCO-5 will provide dust control in Crusher House CH-1. Surge Hopper HPR-4 will have dual outlets, each equipped with a rack & pinion slide gate. Coal will be discharge from HPR-4 outlets using Variable Frequency Drive Feeders FDR-7 and FDR-8, which will feed 660 TPH Ring Granulator Crushers (2 x 100%), CR-1 and CR-2 respectively. Belt Conveyors CVY-6 and CVY-7 will each be 36”, 660 TPH and will deliver crushed coal from Crusher House CH-1 to Transfer Tower TT-3. These two conveyors will each be equipped with Tramp Metal Detectors, TMD-1 on Belt Conveyor CVY-6 and TMD-2 on Belt Conveyor CVY-7. Belt Conveyors CVY-6 and CVY-7 also will be equipped with a swing arm as-fired sample cutters which will collect the coal samples from the belt and send them to the modular Sampling System House SAM-2 located at ground elevation. Inside Transfer Tower TT-3, the discharge of Belt Conveyors CVY-6 and CVY-7 will each have a 3 way motorized flop gate to provide complete cross-over redundancy to feed any Unit 4 Silo. Each gate can discharge to the center Silo 4C, Reversing Belt Conveyor CVY-8, or Reversing Belt Conveyor CVY-9. Reversing Belt Conveyor CVY-8 will be 42”, 660 TPH and deliver coal to Silo 4A and 4D. Reversing Belt Conveyor CVY-9 will be 42”, 660 TPH and deliver coal to Silo 4B and 4E. Dust Collection System DCO-6 will provide dust control in Transfer Tower TT-3 and the coal silos. Coal also will be sent to existing units 1, 2, and 3. Belt Conveyor CVY-10 will transfer coal from Transfer Tower TT-2 to Transfer Tower TT-4. Dust Collection System DCO-7 will provide dust control in Transfer Tower TT-4. Belt Conveyor CVY-10 will discharge onto Belt Conveyor CVY-12. Coal also will be reclaimed from the yard by a Stamler



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Feeder FDR-9 at a rate from 0-400 TPH. The Stamler Feeder, FDR-9, will be equipped with a breaker and discharge onto Belt Conveyor CVY-11. Dust Suppression System DS-3 will provide dust control at the discharge of FDR-9. Belt Conveyor CVY-11, 30” 400 TPH, will discharge on to Belt Conveyor CVY-12. Belt Conveyor CVY-12, 30” 400 TPH, will be equipped with a Belt Scale SCL-6. The discharge of Belt Conveyor CVY-12 will be equipped with inline Magnetic Separator SEP-4. Belt Conveyor CVY-12 will discharge onto Belt Conveyor CVY-13 inside Transfer Tower TT-5. Dust Collection System DCO-8 will provide dust control in Transfer Tower TT-5. Belt Conveyor CVY-13, 30” 400 TPH, will convey the coal to an Existing Transfer Tower. Inside this Existing Transfer Tower, Belt Conveyor CVY-13 discharge will be equipped with a 2-way motorized flop gate. The coal will be directed into Hopper HPR-5 or HPR-6 which will be above the existing coal handling systems for units 1, 2, and 3. Dust Collection System DCO-9 will provide dust control for the new equipment in the Existing Transfer Tower. Hopper HPR-5 will be provided with a cut-off gate to feed the existing splitter gate. Hopper HPR-5 will also be provided with a side discharge chute that will be equipped with a cutoff gate. The side discharge chute and gate will be used to load coal trucks. An enclosed structure along with Dust Collection System DCO-10 will provide dust control for truck loading. Hopper HPR-6 will be equipped with a Variable Frequency Drive Feeder, FDR-10, capable of 0-200 TPH. Feeder FDR-10 will discharge on to existing 3 Belt Conveyor. 1.3.3 Equipment Description. Train Positioner. The train positioner will be at the exit end of the dumper and capable of automatically positioning a train of 150 cars each weighing 286,000 lbs. to 315,000 lbs., and four (4) locomotives. The positioner will incorporate all necessary safety devices to prevent damage to the train and/or positioner in event of a power failure or emergency. The positioner will be equipped with a hydraulic cable tensioning device. The unit train will be under the control of the positioner arm or wheel chocks at all times. The positioner will incorporate entry truck type chocks to insure immobilization of the train during the offloading of the rotary coupled train. A set of exit hook and pawl chocks will be provided and used in conjunction with the entry chocks, to hold empty cars during the offloading of unit-rain and random cars. Rotary Railcar Dumper. The rotary car dumper will consist of a rotating cradle of suitable size and structural rigidity resting on a double set of trunnion wheels mounted on foundations. The dumper will be driven by an electromechanically driven system proven suitable for the type of services and duty specified. The dumper will include a movable platen, stationary spill girder and gravity setting mechanical car clamp system. The dumper will be designed for unit car unloading.



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The car dumper will consist of the following components:

Drive Mechanism, Rack & Pinion. The rotation of the dumper will be accomplished by a single motor connected through a flexible coupling to speed reducer unit. The low speed output shafts of the speed reducer will be flange coupled to line shafts, which will then be coupled to the pinion strands compete with drive rack gears located on each end ring.

Rotating Cradle. The rotating cradle will be a structural steel frame incorporating two end rings and supported on a total of eight wheels, four under each end ring. The rotating part of the dumper will consist of a rigid structure, capable of withstanding as an integrated unit, all forces resulting from its function of inverting railcars.

Platen. The platen will be a structural steel table carrying car rails and supported on rollers. The connection of the platen to the rotating cradle will be such that the platen will be suitably supported and guided in the event the cradle is rotated when there is no car in the dumper.

Bucket Wheel Stacker/Reclaimer. The bucket wheel stacker/reclaimer will be rail mounted hinged bascule, single counterbalanced slewing/luffing boom, cell-less bucket wheel type stacker/reclaimers with retractable trailer including an elevating conveyor, capable of both automatic and manual stacking to and reclaiming from double stockpiles located at both sides of its rail track. The following are the major components of the bucket wheel stacker/reclaimer.

Fixed Gantry. The fixed gantry will have a travel mechanism with flanged wheels 50% of which will be driven by electric motors and gear reducers. The slewing mechanism will be mounted on the fixed gantry structure, incorporating large-diameter anti-friction bearing with ring gear including its drive mechanism and slewing ring locking assembly. Slewing drives will be variable frequency drives.

Rotating Structure. The rotating structure will be mounted on the slewing ring (bearing) enabling the entire structure to rotate. The rotating structure will support boom with associated boom conveyor, operators cab, bucket wheel and the counterweight boom. The entire boom assembly will be hinge mounted on the rotating structure and can be raised and lowered with hydraulic lift mechanism mounted on the rotating structure.

Belt Conveyors. The conveyor subcomponents include the conveyor belt, idlers, pulleys, take-ups, bearings, belt cleaners, drives, motors, drive base-plates, walkways,



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stringers, supports, head and tail frames, foundations, and all other appurtenances necessary for each of the individual conveyors. All conveyors will have full conveyor hoods and wind guard except those located in an enclosed gallery. The travel distance of Stacker/Reclaimer SKR-1 will not have conveyor hoods but will be provided with wind guards. A walkway on one side of the conveyors will be furnished for single conveyors 36 inches in width and less. One walkway will be provided for dual conveyors. Two walkways will be provided for 72 inches in width. Enclosed conveyor trusses will be suitable for use with a wash down system. Telescopic Chute. A telescopic chute will be provided at the discharge end of the “Stockout Conveyor” to control dust emissions during stock piling of the coal. The telescopic chute will consist of steel fabricated concentric tubular sections telescoping into each other as required for stock piling of coal into a conical pile. The telescoping sections of the chute will be lifted or lowered by a motorized winch. Belt Feeders. The function of the belt feeders will be to receive coal from the hoppers located above the feeders and feed to the belt conveyors located below the feeders at a fixed or variable rate. Coal Crushers. The coal crushers will be ring granulator type crushers which will be able to produce 660 TPH of 1-¼ inch product while receiving raw coal of 3 x 0 inches. The crushers will have a rugged heavy-duty dust-tight frame of welded or cast steel construction. All internal wear parts will be made of manufacturer’s recommended steel and will be replaceable. The main shaft will be manufacturer’s recommended steel and will be equipped with heavy-duty roller antifriction bearings arranged for grease lubrication. The crushers will be equipped with externally adjustable devices to permit control of product size and to compensate for wear. Metal Detectors. The metal detectors will be of the electronic type which will continuously monitor the conveyor belts for tramp metals. The metal detectors will be designed to detect all types of tramp metal, whether ferrous, nonferrous, magnetic, or nonmagnetic, from the entire width of the material being conveyed on the conveyor belt. Magnetic Separators. The magnetic separator will be the overhead, manual cleaning suspended type or self-cleaning, belted in-line, type. The magnetic separator will be housed completely inside dust covers. The self cleaning magnetic separator will be positioned above and forward of the conveyor head pulley. The magnet will be sloped towards a tramp iron chute. The tramp iron chute will transport tramp iron to a collection box at grade. Belt Scales. The primary function of the belt scale will be for feed rate control and material inventory monitoring. The belt scales will be the 3 or 4-idler precision digital electronic type with solid-state circuitry and built-in, self-testing devices. The scales will also be provided with test weights for self calibration. Each belt scale will use an environmentally sealed, temperature-compensated, load-sensing device and weigh bridge.



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The scales will weigh and totalize to a value within either ¼ % or ½ % of the test load at flow rates between 25% and 100% of the scale system’s calibrated capacity. Dust Control. The purpose of the dust control equipment will be to minimize the escape of fugitive dust into the atmosphere from the coal handling system. Two types of dust control equipment will be used, dust collection and wet dust suppression.

1. Dust collection systems- DCO-1 thru DCO-10: The dust collectors will be induced draft filter bag units, enclosed in stiffened plate housings and supported on wide flange column legs. Dust-laden air will be directed to the inlet plenum at the dust collector units through ductwork. After passing through the filter bags, the filtered air will be drawn from the units by induced draft fans and discharged to the atmosphere. Dust collected by the filter bags, as well as dust precipitated within the unit, will fall in hoppers which will form the unit housing bottoms. A rotary vane type air lock valve will be furnished at each point where hopper-collected dust is to be transferred from the vacuum condition in the collectors to an atmospheric/pressure region. The dust from the hoppers will be transferred to the nearest conveyor or mill silo.

2. Wet dust suppression systems- DS-1 thru DS-3: Where the coal is to be transferred from one conveyor to another in open areas or where the coal is being stock piled by a telescopic chute or the stacker/reclaimer, the preferred method of dust control will be wet dust suppression. Dust suppression systems use a mixture of water and a surfactant chemical which will be sprayed through nozzles into the conveyor transfer chutes and skirt board areas. The spray captures the fugitive dust and the heavier particles fall back into the coal stream. Each dust suppression system will consist of a pump and proportioner skid which will mix the water and the chemical in the desired proportion. This mixture will then be pumped to the nozzle headers for application to the coal. Each pump skid will be enclosed in an insulated and heated enclosure or in an enclosed and heated building. Piping for dust suppression systems will be heat traced where exposed and will be arranged to drain to a system low point.

Documents

Revised Appendix D System Descriptions - Plains Justice