The effect of moisture on the grindability of Indonesian coals

The effect of moisture on coal grindability has been studied experimentally using the standard Hardgrove machine. Two types of Indonesian coal were investigated, viz a brown coal and a high volatile bituminous C coal. Two types of grindability measurement were adopted for the experiment, viz constant weight basis (the A.S.T.M standard) and constant volume basis. The experimental results show that the grindability of the coals tested is influenced by the moisture content, particularly for the brown coal type which contains very high moisture.