Improved fluid bed combustor efficiencies through fines recycle

Conference · Tue Apr 01 00:00:00 EST 1980

OSTI ID:5512653

Rickman, W. S.

Carbon burnup efficiencies of 99.9% and higher have been attained on a 0.4-MW(t) atmospheric fluid bed combustor with fines recycle. A cyclone and sintered metal filter system separated the fines from the off-gas stream, returning them at 600/sup 0/C (1150/sup 0/F) to the fluid bed. The fines were metered through a unique rotary valve that also served as a pressure boundary between the fluid bed and the fines recycle hopper. Combustor operation was fully automated with a 100-channel process controller and supervisory computer. This high combustion efficiency is especially significant, since the fuel was graphite sized to less than 5 mm (1.3 in.) maximum size. More than 30% of the feed was fine enough to be quickly entrained, placing a substantial burden on the fines recycle system. Detailed modeling techniques were successfully developed to allow prediction of recycle rates and temperatures needed to maintain high combustion efficiency. This model has now been used to analyze coal combustion tests sponsored by Electric Power Research Institute. Surface reaction rate constants were first determined using combustor data taken during cold, low-flow fines recycle tests. These were then used to predict the effect of higher rates of recycle at various temperatures.

• Research Organization: General Atomic Co., San Diego, CA (USA)
• DOE Contract Number: AT03-76SF71053
• OSTI ID: 5512653
• Report Number(s): GA-A-15835; CONF-800428-4
• Resource Relation: Conference: 6. international conference on fluidized bed combustion, Atlanta, GA, USA, 9 Apr 1980
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
42 ENGINEERING
COAL
FLUIDIZED-BED COMBUSTION
COAL FINES
CYCLONE SEPARATORS
EFFICIENCY
FILTERS
MATHEMATICAL MODELS
RECYCLING
CARBONACEOUS MATERIALS
CHEMICAL REACTIONS
COMBUSTION
CONCENTRATORS
ENERGY SOURCES
EQUIPMENT
FOSSIL FUELS
FUELS
INERTIAL SEPARATORS
OXIDATION
POLLUTION CONTROL EQUIPMENT
THERMOCHEMICAL PROCESSES
014000* - Coal
Lignite
& Peat- Combustion
421000 - Engineering- Combustion Systems