Desulfui-ization with Limestone in Fluidized Bed Coal Combustor

Abstract

The efficient capture of SO, by limestone in fluidized bed combustor dependson various factors such as Ca/S mole ratio, operating conditions, type and size of limestoneused. This project aims to study the effect of Ca/S mole ratio on percent SO,retention in a 45 x 45 cm² fluidized bed combustor when the bed temperature, airvelocity and limestone size are varied. Coal and limestone samples were respectivelyfrom Lumpoon and Chiangrai Provinces which are in the northern part of Thailand

From the experimental results, the removal efficiency of SO2 increases withbed temperature and air velocity, but decreases when limestones size increase. For allexperiments the similar trend of increasing %S0₂ retention with Ca/S mole ratio wasobserved. The retention was more than 80% when Ca/S mole ratio was above 2.80.The removal efficiency was nearly the same when this results were applied for the2MW fluidized bed boiler installed at Royal Food Processing Plant, Chaingrai.