Gas Control and Coalbed Methane Development Cooperation Project Group of Qiyuan Mine,China United Coalbed Methane Corporation Limited

针对七元煤矿低孔、低压、低含水饱和度、高变质程度的煤储层特点和筛管完井煤层气解吸困难情况,为了实现瓦斯治理与煤层气共同开发的需要,探索出一套煤层气水平井筛管完井下的注氮增产改造技术。利用顶替排液、氮气驱替、憋井放喷3种氮气改造模式的不同特点,实施多次"注氮-憋压-放喷"作业,通过注氮改造可以清除近井污染,沟通煤层割理裂隙,改善井筒远处煤层渗透率,建立单相气体渗流通道,实现煤层气高效开发的目的。结果表明:七元煤矿5组水平井实施注氮增产改造技术后,单井日产气量提高3~20倍,实现了单井产量的突破。

According to the seam reservoir featuresof the low porositylow pressure,/ow water saturation and high metamorphic degree and the desorption dificultconditon of calbed methane in the screen pipe and completion in aiyuan Mdine, n orderto realize therequirements of the gas control and coalbed methane joit development,a compleed gas output improvement and reconstrucion tehnolgy by nirogen ineclion was discovered under the scren pipe and completion of the coalbed methane horzontal well.with the different features ofthedislaced drainage liquid.ntirogen displacement,suppressed well and blowout three nirogen reconstrucion modes appied,ntiti tragen injecton.pressure suppressed.b1owout operations were conducted.W ith the ntrogen injecion reconstruction.thepaoliton near the well coud be cleaned.the sean cleat cracks coud be linked up.,the seam pemealilt far from the mine shaft asimproved ,a single phase gas seepage channel was established and the high eficient development target of the coalbed methane was realized.The results showed that afer the gas outut improvement and reconstouction technologyof c albed methane horizontal well ly ntrogen injecion in Qilyuan Mine was used,a dail gas production of a single well was improved by 3 ~ 201times and a breakthough of a single well production was realized.

中海石油有限公司2015-2016年科技资助项目(YJQYWS-14-33)；