矿物质对高碱煤显微组分热解特性的影响  

Effects of minerals on pyrolysis characteristics of maceral in high-alkali coal

作　　者：李首毅[1] 林雄超[1] 鲁倍倍 王永刚[1] 张登跃 周云辉 LI Shouyi;LIN Xiongchao;LU Beibei;WANG Yonggang;ZHANG Dengyue;ZHOU Yunhui(School of Chemical and Environmental Engineering,China University of Mining and Technology,Beijing 100083,China;China Pingmei Shenma Group,Pingdingshan 467000,Henan,China)

机构地区：[1]中国矿业大学(北京)化学与环境工程学院,北京100083 [2]中国平煤神马集团,河南平顶山467000

出　　处：《化工进展》2019年第8期3650-3657,共8页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金(21406261)

摘　　要：利用固定床热解炉和热重分析仪研究了沙尔湖煤显微组分的热解特性和产物产率,考察了酸洗处理对热解产物和动力学参数的影响。结果表明:经浮沉实验发现镜质组富集于S2(密度为1.4~1.5g/cm^3浮选煤样)中,惰质组富集于S3(密度为>1.5g/cm^3浮选煤样)中,其中S3所含硅铝酸盐类矿物显著高于S2。且碱及碱土金属(alkali and alkaline earth metals, AAEM)多以可溶性形式存在,经酸洗处理后剩余矿物质主要为石英、高岭土及硅酸盐类。在选用不同煤样进行热解特性分析发现,碱及碱土金属的存在会抑制热解主反应阶段的挥发分释放,而在二次脱气阶段,AAEM矿物质则会提高挥发分的释放速率。且在热解实验中发现,AAEM在热解中会充当煤大分子结构的交联点,降低热解焦油产率。对比不同显微组分发现,惰质组热稳定性更强,镜质组中烷烃侧链较多,芳香度较小,更易受热断裂。采用Doyle积分法确定了沙尔湖煤热解反应的动力学参数。The fixed bed furnace and thermogravimetric analyzer were used to investigate the pyrolysis characteristics and products distribution of maceral in Shaerhu coal. Furthermore, the influence of acid washing treatment on pyrolysis products and kinetics of Shaerhu coal was also discussed. The vitrinite was enriched in S2(the densities ranging from 1.4-1.5 g/cm^3) and the inertinite was enriched in S3(the densities ranging from >1.5 g/cm^3) with the floatation experiments. The content of silicate minerals in S3 was more than that in S2. And AAEM(alkali and alkaline earth metals) was existed in soluble form. The results showed that the acid washing of coal could remove most of the minerals, and the residual minerals were mainly quartz, kaolinite and silicate. The release rate of volatiles during the pyrolysis stage was inhibited, while during the secondary degassing stage it was raised in the presence of alkali and alkaline earth metals(AAEM). The release rate of volatiles during the main pyrolysis stage and final weight loss reduced. In this case, the decreasing yield of tar lied in the fact that AAEM was regarded as the crosslinking point for coal macromolecules in pyrolysis. Compared with different macerals, the thermal stability of inertinite group was stronger. The vitrinite group had more alkane side chains, less aromaticity and more susceptible to thermal fracture. The kinetic parameters of coal pyrolysis were obtained by the processing method with Doyle integration.

关 键 词：沙尔湖煤 酸洗 热解 傅里叶红外光谱 动力学参数 

分 类 号：TQ530.2[化学工程—煤化学工程]