Coalbed Methane Research Center,China University of Petroleum(Beijing) MOE Engineering and Research Center of
Gas Energy Development and Uilization,China University of Petroleum(Beiing) Anton Oil Technology(Group)
Company Limited

为便于科学地指导煤层气开发,依托WL1井组生产资料,探索了煤层气规模开发条件下的煤储层特征及其流体特征变化规律。研究发现,规模化开发条件下,随着井网长期持续的排水降压,逐步形成区域压力降,较大范围的煤层气被解吸,煤层气由吸附态转变为游离态。游离态煤层气在浮力作用下向高部位聚集,而煤层孔隙内的水在重力作用下向低部位聚集,即气水分异现象。依据气水分异理论,提出了合理布局开发井网、先施工低部位的生产井等方案,以提高规模开发效果。

In order to scientifically guide the coalbed methane development,based on the production information of WL1 well group,the paper discovered the coal reser voir features and its fluid feature variation law under the condition of the coalbed methane scale development.The study showed that under the scale development conditio n,with a long term sustained water drainage and pressure reduction of the coalbed methane well network,a regional pressure drop was steadily formed,the coalbed methan e in large scope were desorbed and the coalbed methane were changed from an adsorption state to a free state.Under a role of buoyancy force,the coalbed methane in fre e state would be gathered at a high level location and under a role of gravity,water in the seam fractures would be gathered in low level location and that was gas and wate r difference phenomenon. According to the gas and water difference theory,the rational layout of development well network,production well with the first construction at the | ow location and other plans were provided in order to improve the scale development effect.

国家科技重大专项资助项目(2011ZX05034-003；2011ZX05062)；