页岩气藏渗流数值模拟及井底压力动态分析  

Numerical Simulation of Shale Gas Seepage and Transient Analysis of Bottom-hole Pressure

作　　者：尹虎[1] 王新海[1] 姜永[1] 陈光喜[1] 王娅妮[1] 汪金如 

机构地区：[1]油气资源与勘探技术教育部重点实验室(长江大学),湖北荆州434023 [2]华东石油局试采大队,江苏泰州225300

出　　处：《长江大学学报（自科版）（上旬）》2012年第8期68-71,5,共4页JOURNAL OF YANGTZE UNIVERSITY (NATURAL SCIENCE EDITION) SCI ＆ ENG

基　　金：国家油气重大专项(2011ZX05015)

摘　　要：根据Langmuir等温吸附方程和Fick扩散定律,结合渗流理论建立了页岩气井渗流数学模型,并对模型进行了数值求解,绘制了井底压力变化曲线,分析了吸附气解吸扩散、表皮系数、Langmuir压力、Langmuir体积对井底压力的影响。结果表明,考虑吸附气解吸扩散,气井井底压力降低减慢;表皮系数增大,井筒附近污染严重,压力降低加快;Langmuir压力接近原始地层压力,井底压力降低最慢;Langmuir体积增大,地层中吸附气解吸量增加,井底压力降低缓慢。Shale gas belongs to unconventional gas,and mainly accumulates in free and adsorbed phases.Shale gas is stored in dark-colored and high-Carboniferous argillaceous source rocks,which has low permeability and low porosity.When the free gas is extracted,the pressure of gas reservoir will drop,and adsorbed gas will be dissociated.In seepage process,shale gas include the desorption of adsorbed gas and diffusion of free gas.The quasi steady state Fick diffusion, Langmuir function and conservation of mass equation are used to build the numerical simulation equation of shale gas seepage.Using finite difference method and computer programming works out the variation diagram of bottom-hole pressure.The influence of diffusion,skin factor,Langmuir pressure and Langmuir volume are analyzed.

关 键 词：页岩气 吸附解吸 扩散 数值模拟 井底压力 

分 类 号：TE331[石油与天然气工程—油气田开发工程]