Cyclone performance; The key to feed utilization in circulating fluidized bed boilers

Conference · Wed Jan 01 04:00:00 EST 1992 · Proceedings of the American Power Conference; (United States)

OSTI ID:7232793

Tsao, T R; Herb, B E; Lewnard, J J; Wang, S I ^[1]

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1. Energy Systems Group, Air Products and Chemicals, Inc., Allentown, PA (US)

High utilization of coal and limestone feedstock in circulating fluidized bed (CFB) combustors is critical to minimize operating costs and solid waste generation. Pilot-scale test results typically indicate 50% calcium utilization (Ca/S = 1:1) and greater than 99% carbon burnout. Recent performance data taken for Stockton CFB indicates that a large fraction of the unburned carbon and unreacted limestone escapes the boiler with the fly ash particles smaller than 100 {mu}m in size. This observation was explained by the short residence times of fine particles in the CFB boiler. An analysis of the CFB system suggests that this problem is caused by the inability of the cyclone to capture smaller particles and return them to the boiler to be more completely utilized. This paper reports that a sensitivity study revealed that feedstock utilization is sensitive to cyclone grade efficiency for small particle sizes. in addition, the results show how bed particle size, fly-bottom ash split, solids recirculation rate, and heat transfer in CFB's are affected by cyclone performance.

• OSTI ID: 7232793
• Report Number(s): CONF-920432--
• Conference Information: Journal Name: Proceedings of the American Power Conference; (United States) Journal Volume: 54:1
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
014000* -- Coal
Lignite
& Peat-- Combustion
AEROSOL WASTES
ALKALINE EARTH METALS
ASHES
BURNOUT
CALCIUM
CARBON
CARBONACEOUS MATERIALS
CARBONATE ROCKS
CIRCULATING SYSTEMS
COAL
COMBUSTION PRODUCTS
COMBUSTORS
CONCENTRATORS
COST
CYCLONE SEPARATORS
ELEMENTS
ENERGY SOURCES
ENERGY TRANSFER
EQUIPMENT
FLUIDIZED-BED COMBUSTORS
FLY ASH
FOSSIL FUELS
FUEL FEEDING SYSTEMS
FUEL SYSTEMS
FUELS
FUNCTIONAL MODELS
HEAT TRANSFER
INERTIAL SEPARATORS
LIMESTONE
MATERIALS
METALS
NONMETALS
PARTICLE SIZE
PERFORMANCE
PILOT PLANTS
POLLUTION CONTROL EQUIPMENT
RESIDUES
ROCKS
SEDIMENTARY ROCKS
SEPARATION EQUIPMENT
SIZE
SOLID WASTES
TESTING
USES
WASTES