COAL PREPARATION METHOD FOR PRODUCING HIGH QUALITY CLEAN COAL WITH SPIRAL SEPARATORS

摘要

PURPOSE:To provide a coal grade discrimination technique, by which, to enhance discrimination accuracy using a simple device and to make it possible to produce selected low ash coal stably, even if the supply of high ash coal is made. CONSTITUTION:High ash fine pulverized coal is discriminated in two stages using spiral coal grade discriminators 2,4. The slurry flow per unit length of spiral in the first stage is limited to 15 to 25 tons/hour.m with a slurry concentration set to 20 to 50wt.%, while the slurry flow per unit length of spiral in the second stage is limited to 20 to 30 tons/hour.m with a slurry concentration set to 5 to 30wt.%. The slurry flow of the first stage is adjusted to be less than that of the second stage.