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

Conference · Wed Jan 01 00:00:00 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-; CODEN: PAPWA
• Journal Information: Proceedings of the American Power Conference; (United States), Vol. 54:1; Conference: 54. annual American power conference, Chicago, IL (United States), 13-15 Apr 1992; ISSN 0097-2126
• Country of Publication: United States
• Language: English

Related Subjects

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