沁水盆地煤储层应力敏感分析及工艺对策

Analysis on stress sensitivity of coalbed methane reservoir in Qinshui Basin and Strategies

随着山西沁水盆地煤层气开发规模的不断扩大,在开发中暴露出来的问题也越来越多。从研究最基础的储层伤害机理着手,对沁水3#煤岩开展了应力敏感性、驱替压差实验,结果表明每口井有一个压降临界值,不同井的临界值不同。生产压差的控制非常关键,超过临界值以后生产压差越大渗透率越低。针对影响煤层气解吸的关键参数,开展了排采控制技术研究,应用自动闭环控制技术实现了井底流压的智能控制,为煤层气田平稳、长期、高效地开发提供了新的技术支撑。

More and more problems emerge in development, as the development scale of coalbed methane（CBM）of Qinshui Basin in Shanxin Province is expanded. Starting from the study of the reservoir damage mechanism, the experiment of stress sensitivity and displacement pressure is conducted on Qinshui 3# coal rock, which shows that each well has a critical drop of ressure and the critical drop of pressure varies from different wells. The control of differential pressure of production is very important. After exceeding the critical value, the higher the differential pressure is, the lower the permeability gets. In view of the key parameters affecting CBM desorption, research on production technologies is carried out. By using the automatic closed loop control technology, intelligent control of bottom hole flowing pressure （ BHFP ） is fulfilled, providing new technologies for smooth, long-term, and high-efficiency development of CBM fields.