高煤阶煤层气开发工程技术的不适应性及解决思路

Inadaptability of high-rank CBM development engineering and its solution idea

为了解决煤层气开发普遍存在的区域储层变化复杂、不同地区工程技术的适应性差异大等问题,基于沁水盆地高煤阶储层的横向变化特征,分析研究了以往煤层气开发中工程技术的应用效果,结合大量室内实验及现场实践,提出了一整套以疏导式开发理念为核心的煤层气开发工程技术思路,形成了以可控水平井和疏通式煤层改造工艺为主体的技术系列。现场应用效果良好,可控水平井钻井周期缩短20%~30%,钻井成本降低30%~50%,直井疏通式改造平均单井日产气增加大于500 m^3/d,有效提高了煤层气开采效益,为今后煤层气高效开发提供了理论与技术支撑。

It is common in the process of coalbed methane(CBM)development that the change of regional reservoirs is complexand the adaptability of engineering is diverse in different areas.To deal with these problems,the application results of engineering whichwas previously used for CBM development were analyzed based on the lateral variation characteristics of high-rank coal reservoirs inthe Qinshui Basin.Then,based on abundant laboratory tests and field application,a complete set of CBM development engineering ideawith the dredge development concept as the core was proposed.And a series of technologies with the controllable horizontal well andthe dredge coal reservoir stimulation technology as the main parts were developed.The test results of field application are remarkableand CBM exploitation benefit is improved effectively.The drilling period of controllable horizontal wells drops by20%-30%,the drillingcost declines by30%-50%,and the average single-well gas production rate after vertical wells are stimulated in the dredge pattern risesby over500m3/d.The research results provide the technical support for the high-efficiency CBM development in the future.