作　　者： ; ;

机构地区： 中国矿业大学资源与地球科学学院

出　　处： 《天然气工业》 2011年第10期47-49,118,共3页

摘　　要： 煤层气等温吸附实验结果表明,煤层对甲烷的吸附能力主要受储层压力、温度的双重影响,过去的研究主要关注煤层气吸附量随埋深(压力)的增大而增大的变化趋势,而对深埋带来的温度升高导致煤层气吸附量减少则关注不够。为此,以鄂尔多斯盆地某深部煤层为例,进行煤层气高温、高压吸附实验,以研究其吸附量随埋深的变化趋势,从而指导煤层气资源评价与目标优选。结果表明:①等压条件下,煤层的甲烷吸附量随温度增高呈线性降低,高温、高压阶段温度增加引起的吸附量降低更为显著;②受温度和压力的综合作用,在较低温度、压力条件下压力对煤层吸附能力的影响大于温度的影响,在较高温度、压力条件下温度对煤吸附能力的影响大于压力的影响;③深部煤层气的吸附量随埋深增加呈快速增大、缓慢增大、逐步减小的变化趋势,最大吸附量深度为900～1 600m。该认识有别于过去认为随深度增大煤层吸附量持续升高的传统观点。 The isothermal adsorption experiments of CBM show that the methanol adsorption capacity of coal seams is mainly controlled by reservoir pressure and temperature.Previous studies focused on the change of CBM adsorption capacity along with burial depth(pressure),while little attention has been paid to the great impact of rising temperature resulting from burial depth.Taking the deep coal seams in the Ordos Basin as an example,we performed isothermal adsorption experiments of CBM under high temperature and high pressure,aiming at identifying the change of methanol adsorption capacity with burial depth and thereby to guide CBM resource evaluation and target selection.The following results are obtained.(1) When the pressure is constant,the methanol adsorption capacity in coal seams lowers down linearly along with increasing temperature and its rapid decline is more significant especially at the high-temperature and high-pressure stage.(2) The impact of pressure on the methanol adsorption capacity of coal seams is larger than that of temperature when both temperature and pressure are low.In contrast,the impact of temperature is larger than that of pressure when both temperature and pressure are relatively high.(3) The methanol adsorption capacity in deep coal seams first rapidly increases,then slowly increases and finally lowers down progressively along with the increasing of burial depth.The maximum methanol adsorption capacity occurs at the depths of 900-1600 m.This understanding is different from the traditional one that the methanol adsorption capacity increases continuously along with the increasing of burial depth.

关 键 词： 鄂尔多斯盆地 深部 煤层气 吸附特征 解吸 等温吸附实验 深度

领　　域： [天文地球] [天文地球]