Abstract
Combustion of high fluoride content coal as an energy resource in China has caused serious fluoride pollution problem. It was reports in 1995 by the Agency for Prevention and Treatment of Endemic Diseases of China that fluorine poisoning caused by water and coal-burning touched 596 millions residents and there are 49 millions cases with dental fluorosis and with bone fluorosis. Fluorine poisoning is very difficult to cure. It is important to control of fluoride emissions during coal combustion.In this work, Ca(OH)2 was used as defluorination agent to decrease fluoride emissions during coal combustion. When the molar equivalency of Ca to S equaled 2, the resulting defluorination efficiency of Ca(OH)2 was 50% and deSO2 efficiency was 63% at 900°C. Experimental results showed that defluorination efficiency increased with decreasing temperature. White-coal, made by coating the surface of a coal briquette with a thin layer of Ca(OH)2, was tested as a new solid fuel. The result shows that the white-coal emits less fluorides and SO2 in both volatile matter combustion and char combustion.
