微波预处理对炼焦中煤破碎解离特性的影响  

Effect of microwave pretreatment on broken dissociation characteristics of coking middlings

作　　者：朱向楠[1,2] 陶有俊[1,2] 何亚群[1,2] 罗成 孙启潇[1,2] 王旭 

机构地区：[1]中国矿业大学煤炭加工与高效洁净利用教育部重点实验室,江苏徐州221008 [2]中国矿业大学化工学院,江苏徐州221008

出　　处：《煤炭学报》2015年第8期1942-1948,共7页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(51374206);国家自然科学基金创新群体资助项目(51221462);教育部博士学科点专项基金资助项目(20130095110010)

摘　　要：为探究微波预处理对炼焦中煤磨矿性质的影响,采用颚式破碎机及棒磨机对炼焦中煤进行破碎试验。预处理前、后煤样的背散射图像分析结果表明:微波诱导煤样产生微米级裂缝,煤样的可磨性显著提高。挤压破碎条件下,经不同时间微波预处理煤样的破碎产物具有近似的粒度分布,微波预处理并没有改善煤样的破碎特性。磨矿试验结果表明:微波预处理可以显著的改善煤样的细磨效果,微波预处理时间、给矿量及磨矿时间对磨矿细度的交互作用明显,建立了3种因素对磨矿细度的模型关系。在相同的粒度要求条件下,微波预处理可以显著的降低磨矿时间。能耗分析结果表明:预处理时间为3 min时,磨矿过程综合能耗可以降低31.24%。磨矿产物密度分析结果表明:磨矿时间相同时,由于微波助磨作用及选择性加热作用,磨矿产物的解离度随预处理时间的延长而增大,预处理时间为3 min时,精煤灰分为10%条件下,精煤产率提高9个百分点。Crushing experiments of coking middlings with microwave pretreatment were carried out by jaw crusher and rod mill for the study of the effect of microwave pretreatment on broken dissociation characteristics. The BSE images of coal before and after microwave pretreatment show that micron cracks were induced by microwave radiation,which can significantly improve the grindability of coal. Under the condition of extrusion,the crushing products of coal samples with different pretreatment times have similar particle size distribution,thus the crushing characteristics cannot be improved by microwave pretreatment. The results of grinding tests show that the microwave pretreatment can significantly promote the fine grinding of coal samples,microwave pretreatment time,feeding quantity and grinding time have significant interaction effect on grinding fineness,the relationship model between three factors with the grinding fineness was established. Microwave pretreatment can significantly reduce the grinding time with same size requirements,the results of energy consumption analysis show that energy consumption can be reduced by 31. 24% for the coal with three minutes microwave pretreatment comparing with untreated coal. Density analysis results of grinding products show that thedissociation of minerals can be improved by microwave pretreatment due to selective heating and microwave assisted grinding characteristic. Yield of clean coal with 10% ash content increases by nine percentage with three minutes microwave pretreatment.

关 键 词：炼焦中煤 微波预处理 背散射成像 挤压破碎 磨矿解离 

分 类 号：TQ520.1[化学工程—煤化学工程]