我国煤层气勘探开发现存问题及发展趋势

针对我国煤层气开发的现存问题及发展趋势,从煤层气固溶体、煤储层多相介质、煤层气超临界吸附、低煤级煤含气量、煤储层多级压力降与多级渗流、水压与气压关系、动态渗透率等方面对我国煤层气基础研究薄弱环节进行了分析;从井间距、排采制度、钻完井增产改造、适应中国煤储层物性的开发工艺、平衡开发等方面对煤层气排采现存问题进行了评述。最后指出,我国煤层气勘探开发趋势是由中高煤级向低煤级储层、由浅部向深部、由单一煤层(组)向多煤层(组)、由地面开发向井地立体式开发、由陆地向海洋、由煤层气单采向煤层气与煤成气共采的方向发展。

Existing problems and development trend of CBM exploration and development in China

This paper begins with an analysis of weak links in coalbed methane(CBM) basic research in China from the aspects of CBM solid solution,multiphase medium in coal reservoir,CBM supercritical adsorption,gas content in low rank coal,multilevel pressure drop and multilevel seepage in coal reservoir,relationship between hydraulic and gas pressure,as well as dynamic permeability.The paper proceeds with review of the existing problems in CBM extraction from the aspects of well distance,production system,yield increase transformation by well drilling and completion,development technology adapting China’s coal reservoir properties and balanced development.The paper ends with the conclusion that CBM exploration and development in China tend to go from intermediate and high rank coal reservoir to low rank coal reservoir,shallow depth to deep depth,single coal bed(formation) to multiple coal seams(formation),ground development to well and ground integrated development,land to ocean and CBM mining to co-mining of CBM and coal-formed gas.