焦煤的石墨化及煤系矿物的变迁研究  

Study of graphitization of coking coal and changes and migration of coal-series minerals

作　　者：姚宗序 杜晨衔 周郑琪 杨建国[1] YAO Zongxu;DU Chenxian;ZHOU Zhengqi;YANG Jianguo(National Coal Processing and Cleaning Engineering Research Center,China University of Mining and Technology,Xuzhou 221116,China;School of Chemical Engineering,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]中国矿业大学国家煤加工与洁净化工程技术研究中心,江苏徐州221116 [2]中国矿业大学化工学院,江苏徐州221116

出　　处：《选煤技术》2021年第6期7-13,共7页Coal Preparation Technology

基　　金：国家科技支撑计划资助项目(2014BAB01B02)。

摘　　要：为研究煤系矿物在煤制石墨过程中的变化规律和迁移过程,采用浮沉试验、煤岩分析以及X射线衍射等表征手段,分析了煤系矿物的形态及其分布。研究结果表明:低密度组分中煤系矿物主要是带状分布的黏土类矿物,有机组分则以镜质组为主;中密度组分中矿物质主要是团状黏土矿物和浸染自生的石英;高密度组分中矿物质主要是单体石英颗粒、团块状碳酸盐矿物、草莓状的黄铁矿。对原料煤的三个密度组分进行同步高温石墨化试验,结果表明:随着原料煤灰分的增加,产晶石墨化度显著提高,在一定程度上表明了煤炭镜质组分和惰质组分在石墨化方面的差异;高密度组分制得的石墨样品石墨化度高达94.68%,属于高度有序的石墨微晶片层石墨。研究还表明:煤系矿物在升温过程中逐渐在原位脱水分解为氧化物,并在1500~2200℃时氧化物以多氧化物混合液态和气态形式从裂隙中逸出,其中铁、硅元素参与煤的石墨化过程,起到催化作用;经过2400℃以上高温处理,石墨产話中仅存在少量碳化硅,剩余成灰矿物以气态形式溢出,或随着石墨化炉排气管中温度的降低以玻璃态熔融混合物形式析出。In order to bring to light the law governing the variation and migration of coal-series minerals in the coal to graphite process,an analysis is made of the occurrence patterns and distribution of coal-series minerals through float-and-sink,petrographic and XRD analysis.Study results indicate that the low-density components in coal are predominantly clay minerals which are distributed in banded form,and the organic constituents are mostly vitrinite;the medium-density components are chiefly clumpy clay minerals and authigenic quarts of disseminated structure;and the high-density components consist principally of monomer quartz particles,lump carbonate minerals and strawberry-lime pyrite.The components in three densities as described above are graphitized at high temperature.As indicated by test results,the degree of graphitiza-tion of the test samples is noticeably increased with the increase of the ash content of the samples;indicating more or less that vitrinite and inert components exhibit different graphitization characteristic;and the high-density components with a graphitization degree as high as 94.68%belongs to a highly-ordered graphite with microcrystalline layered texture,It is also observed that the coal-measure minerals tend to gradually dehydrate and escape out of the cracks as polyoxide mixture in either liquid or gas form at a temperature of 1500~2200℃;the iron and silicon elements play a catalytic role in the graphitization process;when the temperature reaches above 2400℃.there exists only tiny amount of silicon carbide in graphitized product,and the rest ash-forming minerals either escape in gaseous form or get separated out as glassy molten mixture with the drop of the temperature in the exhaust pipe of graphitization furnace.

关 键 词：煤制石墨 物理分选 矿物迁移 高温石墨化 催化石墨化 

分 类 号：TD94[矿业工程—选矿] TQ127.1[化学工程—无机化工]