Contract Order:
2006
 
Commercial Operation:
2008

HPB Scope of Supply

Coal-fired internal recirculation circulating fluidized-bed (IR-CFB) boiler including:

• Structural steel
• Fans and motors
• Tubular air heaters
• Economizer
• Multi-cyclone dust collector (MDC)
• Ash recycle/reinjection system
• Limestone injection system
• Limestone silo
• Startup burners
• Refractory lined lower furnace with erosion protection at the Reduced Diameter Zone (RDZ) transition
• Fluid bed ash coolers
• Bed drain system including screws, screeners, crushers, belt conveyor and bucket elevators
• Multi-cyclone dust collector screws
• Flues and ducts
• Segmented U-beam primary particle collectors with watercooled support system
• Coal feeders and bunkers
• Blowdown tanks
• Instrumentation and controls

Environmental Equipment

• Pulse jet fabric filter

• Boiler type: Internal Recirculation CFB design
• Design fuel: Bituminous coal
• Startup fuel: Light (diesel) oil
• Capacity: 256 MWt
• Steam flow: 750,000 lb/h (94.5 kg/s)
• Steam pressure: 1536 psig (10.6 MPa)
• Steam temperature: 925F (496C)

• The steam produced by the CFB boiler, in conjunction with the existing steam generation units, will fulfill the needs of the alumina production process in a safe, reliable and efficient manner.
• The addition of limestone to the circulating bed reduces sulfur dioxide (SO2) emissions from the boiler.
• Low furnace temperatures and staged combustion limit nitrogen oxides (NOx) emissions.
• Unique two-stage solids collection system using U-beams and MDC provides superior collection efficiency. The recycling of solids collected by the MDC improves combustion efficiency and limestone utilization.
• The U-beam and MDC solids collection system requires significantly less maintenance than hot cyclones.
• RDZ design with silicon carbide tiles at the top edge of the furnace refractory is used to minimize tube erosion at the interface.