Development of a prototype of rice husk fluidized bed combustor

Abstract

Fluidized bed combustion of rice husk was carried out in a pilot scale prototype fluidized bed combustor. The combustor unit design incorporated a nozzle stand pipe plate distributor, a reaction vessel, a solid feeder, and instrumentation. The reaction vessels comprise an air plenum, a firebox and a freeboard zone. The combustor, 1.2 * 1.2 m² in square cross sectional area with a height 3 m, is contained with bed particle (sand) of 0.40 mm. diameter with a bed height of 40 cm. Rice husk was feed in range 117-203 kg/hr using a screwfeeder into the bed. The superficial fluidized bed velocity was the range 0.13-0.20 m/sec with a bed temperature between 550-700 ℃ using charcoal at starting fuel. The pressure used was atmospheric. The fluidized bed combustion of rice husk generates heat energy which had Thermal efficiency % 23-35 % variable by air feed rate and rice husk feed rate.