致密砂岩气藏拟稳态流动阶段气井产能分析  

Productivity analysis of tight sandstone gas reservoir in pseudo-steady state

作　　者：雷刚[1] 董平川[1] 杨书[1] 王彬[1] 李振[1] 

机构地区：[1]中国石油大学(北京)石油工程教育部重点实验室,北京102249

出　　处：《油气地质与采收率》2014年第5期94-97,117,共4页Petroleum Geology and Recovery Efficiency

基　　金：国家自然科学基金项目"裂缝性油气藏流固耦合渗流基础研究"(50004002)

摘　　要：为研究致密砂岩气藏应力敏感对拟稳态流动阶段气井产量及无阻流量的影响,基于气体非达西渗流特性,考虑渗透率幂函数式应力敏感,推导了致密砂岩气藏在拟稳态流动阶段的气井产能方程,并得到了气井无阻流量计算公式。实例计算结果表明:渗透率幂函数式应力敏感使拟稳态流动阶段气井产量及无阻流量减少;受到渗透率幂函数式应力敏感影响,生产井产能曲线向压力轴弯曲,在相同的生产压差下,气井产量比不考虑渗透率幂函数式应力敏感的产量低;渗透率幂函数式应力敏感系数越大,产能方程曲线弯曲越早、弯曲度越大,气井产量越低,产量下降率越大;地层压力下降后,生产井受渗透率幂函数式应力敏感影响减弱,在平均地层压力较低时,可适当放大生产压差进行生产。Based on non-Darcy gas seepage characteristics in porous media, a new productivity equation was presented for tight reservoirs in pseudo-steady state considering the effect of power function stress sensitivity. And the open flow capacity calculation formula of gas wells was derived. The computation result of an example showed that: the stress sensitivity phenomenon reduced the productivity and open flow capacity of gas wells in pseudo-steady flow period. The productivity curve of producer bended towards the pressure axis and the productivity was lower than that calculated from the equation without stress sensitive coefficient under the same producing pressure drop. The larger the power function stress sensitive coefficient was, the earlier and severer the productivity curve bended, and the lower the productivity was and the larger the yield reduction rate was. With the decline of reservoir pressure, the effect of stress sensitivity would be reduced for producing well. It would be appropriate to enlarge producing pressure drop when the average formation pressure was lower.

关 键 词：致密砂岩 拟稳态 非达西渗流 渗透率幂函数式应力敏感 无阻流量 

分 类 号：TE312[石油与天然气工程—油气田开发工程]