煤矸石分级分质加工与利用的研究

Study on the grading and quality-separating processing and utilization of coal gangue

对煤矸石的分级分质加工利用是解决其大宗利用的有效方法之一,在前人对煤和矸石选择性破碎研究的基础上,以山西焦煤集团屯兰煤矸石为研究对象,重点对煤矸石分级分质利用进行研究,尤其是对煤矸石破碎后煤与石的分布规律进行系统研究。研究发现,煤矸石破碎后煤向细粒级富集,而石向粗粒级富集。屯兰煤矸石经过鄂式和锤式多重破碎和筛分分级后,每次破碎结果均呈现出粒度越小灰分越低发热量越高、粒度越大灰分越高发热量越低的分布规律。煤矸石的选择性破碎优先在煤矸石层理面与节理面发生,屯兰煤矸石通过选择性破碎,一次性破碎分级分质能获得高位热值为7.06~13.22 kJ/g的矸石电厂燃料,而多重破碎具有显著的分级分质效果,能分出高位热值为7.13~7.71 kJ/g的矸石电厂燃料,同时能制备出灰分高达83%以上、产率36%左右、压碎值低于30%的砂石骨料,对于煤矸石建材化的大宗利用和解决屯兰煤矸石的排放具有重要意义。

The grading and quality-separating processing and utilization of coal gangue was one of the effective methods to solve its bulk utilization.Based on the previous research on the selective crushing of coal and gangue,taking coal gangue from Tunlan Coal Mine of Shanxi Coking Coal Group as the object,the grading and quality-separating utilization of coal gangue was studied,especially the distribution law of coal and rock after coal gangue crushing was studied systematically.It was found that after the coal gangue was broken,the coal enriched to the fine-grained level,while the gangue enriched to the coarse-grained level.After multiple crushing and screening grading of coal gangue from Tunlan Coal Mine by jaw and hammer crush,it showed the distribution law that the smaller particle size,the lower ash content and higher calorific value;the larger particle size,the higher ash content and lower calorific value.Selective crushing of coal gangue took place preferentially on the bedding plane and joint plane of coal gangue.Through selective crushing,the gangue power plant fuel with high calorific value of 7.06~13.22 kJ/g could be obtained by one-time crushing,grading and quality-separating,while multiple crushing had significant grading and quality-separating effect,and could separate gangue power plant fuel with high calorific value of 7.13~7.71 kJ/g,at the same time,sand aggregate with ash content of more than 83%,yield of about 36%and crushing value of less than 30%could be prepared,which was of great significance for the bulk utilization of coal gangue as building materials and solving the discharge of coal gangue from Tunlan Coal Mine.