2004 Volume 83 Issue 5 Pages 360-366
Research on the control of fluoride emissions from coal combustion is necessary to solve a serious fluoride pollution problem. In this work, CaCO3 and Ca (OH) 2 were used as defluorination agents to decrease fluoride emissions during coal combustion. When the molar equivalency of Ca to F2+S equaled 1.8, 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 increasing fuel ratio of coals or 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 content combustion and char combustion.