The effects of solid absorbents on the emission of trace elements, SO2, and NOx during coal combustion

The emission of toxic metals from the combustion of fossil fuels is an important global environmental issue. Solid absorbents can be used to control the emission of toxic trace elements from coal combustion. In this paper, limestone, CaSO4, bauxite, kaolinite and CaO are employed for this purpose and experiments are carried out in an electrically heated drop-tube furnace. The trace elements investigated are Pb, Cd, Cr and As. It is observed that the absorptive capacity is related to the qualities of the absorbents (type, amount and particle size) and the combustion temperature. The results also show that some absorbents can reduce SO2 emission simultaneously, but no influence on NOx emission. Copyright (C) 2001 John Wiley & Sons, Ltd.