煤层气储层研究进展

Research progress in coalbed methane reservoir

黄孝波 2 李贤庆 2 王萌 2 凌标灿³ 孙杰 2

中国矿业大学煤炭资源与安全开采国家重点实验室，北京 100083 中国矿业大学地球科学与测绘工程学院，北京 100083 华北科技学院安全工程学院，北京 101601

煤层作为煤层气储层，具有容纳气体和允许气体流动的能力。与常规的砂岩储层不同，煤层气在煤层中主要呈吸附态形式存在，其储集性能受多种因素的影响。我国的煤田大多成煤时间早，经历的构造期次多，地质条件复杂，造成我国煤层气储层物性非均质性强，研究难度较大。文中总结了煤层气储层的物性特征、储集状态、煤岩特征、实验方法4方面的研究进展，指出煤储层的渗透性、孔隙度、外生裂隙、割理、微裂隙等特征可以表征其物性；温度、压力、含气量、水动力条件、应力状态可以反映其储集状态；煤岩类型、煤体结构、煤层厚度、显微组分组成、变质程度、灰分等也影响其特性。最后，探讨了煤层气储层研究存在的问题及下一步研究方向。

As a reservoir of coalbed methane (CBM), the coal seam enables gas to flow and accommodate in it. Different from the conventional sandstone reservoir, the major CBM in the coal seam exists in the adsorbed form and the CBM reservoir is impacted by a lot of factors. Most coalfields in China were formed relatively earlier, experienced many times of tectonics and had complex geological conditions. Thus, the CBM reservoir in China has strong heterogeneity and is difficult to study. This paper summarizes the characteristics of physical property, occurrence state, coal petrology and experimental method of CBM reservoirs. It is suggested that the porosity, permeability, cracks, cleats and micro-cracks can reflect the physical property of CBM reservoir. Temperature, pressure, gas content, hydrodynamic condition, stress state can also reflect the status of CBM reservoir. Coal petrology, coal structure, thickness, macerals composition, metamorphic grade and ash content can impact the characteristics of CBM reservoir. Finally, the main problems and next research orientation in CBM reservoirs are further discussed.

10.6056/dyyqt201203008