中国长焰煤物性特征及其煤层气资源潜力  

Physical Characteristics and CBM Resources Potential of Long Flame Coal in China

作　　者：简阔[1,2] 傅雪海[1,2,3] 王可新[1,2] 张玉贵[4] 

机构地区：[1]中国矿业大学资源与地球科学学院,江苏徐州221008 [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 [3]新疆大学地质与矿业工程学院,新疆乌鲁木齐830047 [4]河南理工大学安全科学与工程学院,河南焦作454000

出　　处：《地球科学进展》2014年第9期1065-1074,共10页Advances in Earth Science

基　　金：国家自然科学基金项目"新疆低煤级储层煤层气成藏模式研究"(编号:41362009);新疆维吾尔自治区引进高层次人才及"天山学者"启动基金项目(编号:11100213)资助

摘　　要：为了评价我国长焰煤储层煤层气开发前景,对全国范围内的34个长焰煤煤样(测试18个,收集16个),进行了煤岩组分、平衡水分、工业分析和物性特征分析,以及等温吸附实验和煤表面能计算。结果表明:长焰煤的平衡水分、干燥无灰基挥发分、空气干燥基水分随煤化程度的增加而减少,孔隙率随煤化程度增大而增大,且孔容分布不均,大孔最多,约占40%,孔比表面积以过渡孔和微孔占绝对优势,二者约占97%;长焰煤的朗缪尔体积随惰质组含量的增加而趋于增大,随镜质组含量的增加呈减少趋势,且煤表面能ΔγL和朗缪尔体积均随煤化程度的增加而增大,随温度的升高而减小,煤表面能对甲烷吸附控制作用明显。估算全国2 000 m以浅长焰煤煤层气资源量为4.3万亿m3,长焰煤孔隙率高,孔径结构分布连续,且连通性较好,其煤层气资源具有开发潜力。当前我国低煤级煤层气尚未取得规模性商业开发的突破,为低煤级煤层气开发提供了长焰煤储层的基础研究,指明了其物性特征及优势,梳理了不同区域的长焰煤煤层气资源,对低煤级中长焰煤煤层气开发具有一定指导意义。In order to evaluate the development prospects of coalbed methane （CBM） of Long flame coal res- ervoirs, we analyzed the coal maceral, equilibrium moisture content, industry analysis and physical characteristics of 34 long flame coal samples （testing 18/collecting 16） nationwide. Moreover, Isothermal adsorption experiments and the calculation of coal surface energy were carried out. The results show that： Equilibrium moisture, dry ashfree volatile and air-dried basis moisture of long flame coal decrease with the increasing degree of coalification, but porosity increases with the increasing degree of eoalification. The pore volume is unevenly distributed, the macro- pore accounts for most of the total volume （ about 40% ） , and the specific surface area of transition pore and micro pore has an absolute advantage （about 97% ）. Langmuir volume shows an increasing trend with increasing iner- tinite content, and shows an decreasing trend with increasing vitrinite content. Besides, both ΔγL and Langmuir volume increases with the increase of degree of coalification, and decreases with increasing temperature. So it is ob- vious that coal surface energy controls the action of methane adsorption. The CBM resources of long flame coal with- in the 2 000 m nationwide were estimated at 4.3 x 1012 m3. The porosity of long flame coal is larger, pore connectivi- ty is better, and pore size distribution is continuous. Thus, the CBM resources of long flame coal has the develop- ment potential. At present, the low rank CBM development in our country has not yet achieved a breakthrough in the scale of commercial development. In this paper, we provided a basis for the study of long flame coal reservoir for low rank CBM development, pointed out its physical characteristics and advantages, and combed CBM resources of long flame coal located in different regions, which has certain guiding significance for CBM development of long flame coal in the low rank coal.

关 键 词：长焰煤煤层气 孔径分布 等温吸附 煤表面能 

分 类 号：P618.13[天文地球—矿床学]