作　　者： ; ; ; ;

机构地区： 中国矿业大学资源与地球科学学院

出　　处： 《煤炭学报》 2014年第3期504-509,共6页

摘　　要： 通过开展鄂尔多斯盆地东缘高中低煤阶不同含水饱和度煤储层应力敏感性实验，研究了煤储层渗透率动态变化规律及其对煤层气产出的影响。实验结果证实：不同煤阶煤储层渗透率随有效应力的增加均呈现负指数函数降低的规律。在有效应力小于5MPa时，煤储层渗透率随有效应力增加快速下降73％～95％，平均87％，煤储层应力敏感性最强；有效应力在5～10MPa时，渗透率随有效应力增加而较快下降5％～18％，平均10．4％，煤储层应力敏感性较强；而当有效应力大于10MPa后，渗透率随有效应力的增加下降速度减缓，应力敏感性减弱。实验结果表明中高煤阶煤储层应力敏感性随有效应力增加要弱于低煤阶。随着煤样含水饱和度的增加，煤储层应力敏感性也逐渐增强。根据煤储层渗透率动态变化规律提出了煤层气井排采过程中应遵循缓慢一保压一持续的排采工作制度，才能获得煤层气最大产出量。 According to the east Ordos Basin coal rank of different water saturation of coal reservoir stress sensitivity lab experiments, the influence of coal reservoir permeability dynamic change rules on the coalbed methane production was studied. Experimental results confirm that medium ＆ high rank coal reservoir permeability decreases in the rule of negative exponent function along with the increasing effective stress. Once the effective stress less than 5 MPa, the coal reservoir permeability with the increasing effective stress quickly fells by 73% -95% , average 87% ,indicating stron- gest stress sensitivity;the effective stress ranges from 5 to 10 MPa, permeability rapidly decreases by 5 % -18 % along with increasing effective stress, average 10.4%, showing strong stress sensitivity ; When the effective stress is higher than 10 MPa, the decline in permeability with the increase of effective stress representing weak stress sensitivity. The stress sensitivity in effective stress of high rank coal is lower than that of low rank coal. With increasing of water satura- tion of coal samples, coal reservoir permeability in stress sensitivity enhances gradually, the production rules of CBM Wells was proposed in processing of slowly depressurizing-continuous producing work flow, based on the reservoir per- meability dynamic change law, in order to attain coalbed methane the maxumum output.

关 键 词： 煤层气 不同煤阶 煤储层 应力敏感性 渗透率

领　　域： [天文地球] [天文地球]