考虑吸附气影响的页岩气井三项式产能计算方法  

A Trinomial Deliverability Calculation Method for Shale Gas Wells Considering the Effect of Adsorbed Gas

作　　者：房大志[1] 刘洪[2] 庞进[2] 谷红陶 马伟骏 Fang Dazhi;Liu Hong;Pang Jin;Gu Hongtao;Ma Weijun(Sinopec Chongqing Shale Gas Company,Chongqing 408400,China;Chongqing University of Science and Technology,Chongqing 401331,China)

机构地区：[1]中国石化重庆页岩气公司,重庆408400 [2]重庆科技学院,重庆401331

出　　处：《特种油气藏》2023年第3期137-142,共6页Special Oil & Gas Reservoirs

基　　金：国家科技重大专项“彭水地区常压页岩气开发技术政策及气藏工程方案”(2016ZX05061-016);中国石化重大科技项目“南川复杂构造带页岩气勘探开发关键技术”(P19017-3)。

摘　　要：针对页岩气吸附解吸对生产井产能影响规律不清晰的问题,基于致密气井的渗流特征和产能方程,从气体渗流微分方程出发,结合Langmuir等温吸附公式,建立考虑页岩气吸附解吸的产能模型,根据页岩气井的钻完井和动态监测资料计算了页岩气井不同解吸时间下的产能和无阻流量,并根据回压试井资料,将吸附气影响转化为附加阻力系数,形成三项式产能计算方程,利用该方程研究了吸附气对页岩气产能计算的影响。结果表明:吸附气会导致页岩气井初期产能计算值偏高,解吸10 d后计算的无阻流量相对稳定;吸附气含量对页岩气井产能影响较大,吸附压力对产能影响较小;三项式产能计算结果与解析法模型计算结果误差小于12%,结果较为可靠。研究成果可为页岩气井产能评价提供参考。To address the problem of the unclear effect law of the shale gas adsorption-desorption on the deliverability of production wells,based on the seepage characteristics and deliverability equation of tight gas wells,a deliverability model considering shale gas adsorption-desorption was established with reference to the gas seepage differential equation and in combination with the Langmuir isothermal adsorption equation;the deliverability and open flow capacity of shale gas wells under different desorption time were calculated based on the drilling and completion and dynamic monitoring data of shale gas wells,and the effect of adsorbed gas was transformed into additional resistance coefficients based on the information of back-pressure well testing to form a trinomial deliverability calculation equation,and this equation was used to study the effect of adsorbed gas on shale gas deliverability calculation.The results show that the adsorbed gas will cause a higher initial deliverability calculation value of shale gas wells,and the calculated open flow capacity is relatively stable after 10 d of desorption;the adsorbed gas content has a greater influence on the deliverability of shale gas wells,and the adsorption pressure has a smaller influence on the deliverability;the error between the results of the trinomial deliverability calculation and the analytical method model calculation is less than 12%,and the results are more reliable.The research results can be used as a reference for the deliverability evaluation of shale gas wells.

关 键 词：页岩气 产能 三项式 吸附气 

分 类 号：TE332[石油与天然气工程—油气田开发工程]