低阶煤气水两相渗流特征的数值模拟研究  

Research on Numerical Simulation of Gas-Water Two-phase Seepage in Low-rank Coals

作　　者：祝捷[1] 侯晨雨 刘谨嘉 唐俊[1] 邵唐砂 邹骐竹 ZHU Jie;HOU Chenyu;LIU Jinjia;TANG Jun;SHAO Tangsha;ZOU Qizhu(School of Mechanics and Civil Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)力学与建筑工程学院,北京100083

出　　处：《煤炭技术》2023年第3期1-4,共4页Coal Technology

基　　金：国家自然科学基金项目(52074297);中央高校基本科研业务费专项基金(2022YJSLJ03)。

摘　　要：以海拉尔盆地伊敏低阶煤为研究对象,建立了考虑煤体三维变形的煤储层气水两相流模型,运用COMSOL软件得到了与伊敏煤样气驱水实验结果吻合的气、水流量和进口气体压力变化曲线。进一步探讨了不同井底流压下降方案(0.005 MPa/d和0.01 MPa/d)的煤储层产气特征。研究表明:煤层气井排采需经历产量提升阶段,在井底流压达到最低值时,产气量达到峰值,然后产量降低进入稳产阶段;减缓井底流压的下降速率有利于保持稳产阶段的产气量。Yimin low-rank coal in Hailar basin were selected as the research object,and the gas-water two-phase flow model of coal reservoirwas established considering the three-dimensional deformation of coal body. Using COMSOL software, the gas and water flow rate and inlet gas pressure curve were obtained which were consistent with the results of the Yimin coal sample gas driving water experiment.The gas production characteristics of coal reservoir under different bottom-hole flowing pressure reduction schemes(0.005 MPa/d and 0.01 MPa/d) were further discussed. The research shows that CBM well drainage needs to go through the production increase stage. When the bottom-hole flowing pressure reaches the minimum value, the gas production reaches the peak value, and then the production decreases and enters the stable production stage;slowing down the decline rate of the bottom-hole flowing pressure is conducive to maintaining the gas production in the stable production stage.

关 键 词：低阶煤 气水两相流 数值模拟 产气量 井底流压 

分 类 号：TE312[石油与天然气工程—油气田开发工程]