黔西比德-三塘盆地主采煤层孔隙特征  

Pore characteristics of the main coal seams in Bide-Santang Basin in Western Guizhou Province

作　　者：周龙刚[1,2] 吴财芳[1,2] 

机构地区：[1]中国矿业大学资源与地球科学学院,江苏徐州221116 [2]中国矿业大学煤层气资源与成藏过程教育部重点实验室,江苏徐州221008

出　　处：《煤炭学报》2012年第11期1878-1884,共7页Journal of China Coal Society

基　　金：国家科技重大专项资助项目(2011ZX05034);国家基础研究发展计划(973)资助项目(2009CB219605)

摘　　要：利用研究区主采煤层煤样做了相关系列实验,结合实验数据分析了煤层中孔隙特征及孔隙表征参数的变化规律,探讨了孔隙特征的地质控制因素。结果表明:比德-三塘盆地主采煤层的孔隙类型主要可以分为四大类;孔隙率在4.06%～10.12%,以微孔和小孔为主,两者占总孔容的80%以上,孔隙退汞效率较高,孔隙形态以开放孔为主,含一定数量的半封闭孔。孔比表面积在18～21 m2/g,微孔所占比例最高。排驱压力主要受孔隙弯曲度影响。体积中值直径多为10 nm左右,面积中值直径平均值为4.58 nm。以Ro,max=2.0%为分界点,孔隙率和孔容随煤变质程度呈现"U"型变化。煤岩显微组分镜质组含量普遍超过70%,控制了微孔和小孔的含量,而矿物质含量的增加总体上对孔隙发育产生不利影响。Through a series of relevant experiments of coal samples in main coal seams of study area, analyzed the vari- ation of the pore characteristics and porosity characterization parameters, discussed the geological factors which control pore characteristics. The results show that the pore can be divided into four big types in main coal seams of Bide-Santang basin. Porosity is range from 4.06% to 10. 12%. Micropore and minipore takes the dominant position, and provides more than 80% of the total pore volume. The mercury withdrawal efficiency is high. Pore forms are main- ly open, contains a number of semi-closed pore. Pore surface area is 18-21 m2/g,micropore occupies the highest pro- portion. Pore tortuosity has significant impact on threshold pressure. Median pore diameter of volume are mostly around 10 nm, the average of median pore diameter of area is 4.58 nm. Porosity and pore volume show ＂U＂ shape tendency with the increase of coal rank, with R = 2.0% as the cut-off point. The content of vitrinite is more than 70% in general control the amount of micropore and minipore. While the increase of minerals＇ content has negative impact on the development of pore system.

关 键 词：比德-三塘盆地 主采煤层 孔隙特征 压汞 

分 类 号：P618.11[天文地球—矿床学]