Liberation characteristics of coal middlings comminuted by jaw crusher and ball mill  

作　　者：Xie Weining He Yaqun Zhu Xiangnan Ge Linhan Huang Yajun Wang Haifeng 

机构地区：[1]School of Chemical Engineering and Technology,China University of Mining & Technology [2]Advanced Analysis & Computation Center,China University of Mining & Technology

出　　处：《International Journal of Mining Science and Technology》2013年第5期669-674,共6页矿业科学技术学报（英文版）

基　　金：supported financially by the National Natural Science Foundation of China(No.51074156;51274196 and51221462)the Natural Youth Science Foundation of China(No.51104160)

摘　　要：The associated minerals make coal middlings possess a relatively high ash content.Subsequent liberation through size reduction can cause recovery increase.However,effect of comminution facilities on mineral liberation of middlings was ignored.This paper studied the liberation characteristics of middlings crushed with different kinds of fragmentation forces.Middlings of 3 mm+0.5 mm sampled from a dense medium cyclone were comminuted by a jaw crusher and a ball mill to 0.5 mm with similar size distribution respectively.The generating mechanism of fnes was also analyzed.Full densimetric analyses indicate that mineral liberation of the product crushed by the jaw crusher is better than that by the ball mill at each fraction.For sizes of 0.125 mm+0.074 mm and 0.074 mm,yields of the product with ash content 11%comminuted by jaw crusher are nearly 20%higher than that by the ball mill.Sectional micrographs observed by the scanning electron microscopy(SEM)also show the same law for these two fractions and some intergrowth particles still exist in the fraction of 0.5 mm+0.25 mm.The associated minerals make coal middlings possess a relatively high ash content.Subsequent liberation through size reduction can cause recovery increase.However,effect of comminution facilities on mineral liberation of middlings was ignored.This paper studied the liberation characteristics of middlings crushed with different kinds of fragmentation forces.Middlings of 3 mm+0.5 mm sampled from a dense medium cyclone were comminuted by a jaw crusher and a ball mill to 0.5 mm with similar size distribution respectively.The generating mechanism of fnes was also analyzed.Full densimetric analyses indicate that mineral liberation of the product crushed by the jaw crusher is better than that by the ball mill at each fraction.For sizes of 0.125 mm+0.074 mm and 0.074 mm,yields of the product with ash content 11%comminuted by jaw crusher are nearly 20%higher than that by the ball mill.Sectional micrographs observed by the scanning electron microscopy(SEM)also show the same law for these two fractions and some intergrowth particles still exist in the fraction of 0.5 mm+0.25 mm.

关 键 词：Coal middlings Fragmentation force LIBERATION Float and sink test Sectional micrograph 

分 类 号：S828[农业科学—畜牧学]