可磨性指数对煤炭混合破碎过程影响的实验研究  

Experimental investigation on the influence of hardgrove grindability indexon the heterogeneous grinding of coal mixture

作　　者：张宇新 谢卫宁 姜海迪 高佳乐 方小霞 陆施澄 张学武 ZHANG Yuxin;XIE Weining;JIANG Haidi;GAO Jiale;FANG Xiaoxia;LU Shicheng;ZHANG Xuewu(School of Chemical Engineering and Technology,China University of Mining and Technology,Xuzhou 221116,China;Advanced Analysis and Computation Center,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]中国矿业大学化工学院,江苏徐州221116 [2]中国矿业大学现代分析与计算中心,江苏徐州221116

出　　处：《煤炭学报》2022年第5期2088-2095,共8页Journal of China Coal Society

基　　金：国家自然科学基金青年资助项目(51904295);内蒙古自治区科技计划资助项目(2019GG274)。

摘　　要：为研究在磨煤机内煤炭混合破碎过程中各组分可磨性指数(HGI)对混合物和各组分破碎行为的影响,借助加装功率测量装置的哈氏可磨仪开展不同可磨性指数无烟煤和肥煤,多时间批次的单独与混合破碎实验。混合物及各组分的哈氏可磨性指数测试结果显示:不同混合比例煤样的HGI均大于各煤样HGI的质量加权平均值,且差异随混合物中高HGI肥煤质量分数的增加而提高,表明混合破碎中两煤种相互作用加速生成细颗粒。为识别并定量煤炭混合物中各组分,分析并计算了不同混合比例样品的X射线衍射图谱特征比值(即002峰峰高与半高宽比值),明确了该特征比值与混合物中无烟煤质量分数的线性关系,进而在分析不同混合破碎条件初始和细粒级破碎产物X射线衍射图谱基础上,获得各组分在上述混合破碎产物中的质量分数。煤炭混合破碎、各粒级产物不同煤种识别定量及过程能耗分析结果表明:两煤种单独和混合破碎的初始粒级破碎速率均符合一级动力学,且随肥煤质量分数增加而提高;易磨肥煤对较硬无烟煤破碎起促进作用,而肥煤破碎速率则因无烟煤质量分数增加而降低;与单独破碎相比,混合破碎可提高各组分细粒级产率,各组分细度t_(10)均随另一组分质量分数的增加而提高。经典能量-粒度关系模型可分别表征各混合物破碎过程。但混合破碎中各物相相互作用降低其抵抗破碎的能力,导致不同混合物破碎能量效率(单位破碎能量所产生煤粉细度t_(10))差异(随其可磨性指数的增加而提高)。在定性分析混合物破碎能量效率与HGI关系基础上,将HGI引入到改进型能耗模型,实现各混合破碎条件能量-粒度数据归一和对不同混合破碎过程的表征。根据混合破碎能量和质量守恒,结合改性型能耗模型,利用神经网络算法计算混合破碎中各组分能耗,发现与单独破碎相比,各组分In order to study the influence of hardgrove grindability index(HGI)on the grinding behavior of mixture and components during the heterogeneous grinding of coal in coal pulverizers,the Hardgrove mill with a power meter was used to conduct the heterogeneous and homogeneous grinding of anthracite and bituminous coal with different HGIs at various grinding time levels.Experimental results show that the measured HGIs of mixtures are higher than the mass weighted average ones and the difference increases with the content of bituminous coal in the mixture.These indicate that the yield of fines is promoted due to the interaction between components in heterogeneous grinding.Aiming to identify and quantify the components in the coal mixture,the characteristic ratios(the ratio of height and full width at half maximum of 002 peak)of various mixtures were calculated based on the XRD patterns.The linear relationship between the characteristic ratio and yield of anthracite in the mixture was confirmed.Hence,the contents of two components in products in the original and fine size under various heterogeneous grinding conditions were computed based on the XRD pattern of above materials.The heterogeneous grinding of coal,the quantification of components in various sized products and the analyses on the consumed energy during the grinding process indicate that the breakage rates of two components in the mixture and single breakage are in accordance with the first-order dynamic,and increase with the more addition of bituminous coal.The soft bituminous coal promotes the breakage of hard anthracite,but its breakage rate decreases with the more anthracite added in mixture.The yield of fine components in the mixture grinding are higher than those in single breakage.And the product t_(10) of one component increases with the more addition of the other component in the mixture.The classical energy-size reduction model can describe the heterogeneous grinding of different mixtures,respectively.As the breakage resistance of components decreas

关 键 词：可磨性指数 混合破碎 破碎速率 能量-粒度关系模型 能量分配 

分 类 号：TQ520[化学工程—煤化学工程] TD94[矿业工程—选矿]