Stress sensitivity of formation during multi-cycle gas injection and production in an underground gas storage rebuilt from gas reservoirs  

作　　者：LI Jiqiang ZHAO Guanqun QI Zhilin YIN Bingyi XU Xun FANG Feifei YANG Shenyao QI Guixue 

机构地区：[1]The Key Laboratory of Complex Oil and Gas Field Exploration and Development of Chongqing Municipality,Chongqing 401331,China [2]School of Petroleum Engineering,Chongqing University of Science and Technology,Chongqing 401331,China [3]Exploration and Development Research Institute of Sinopec Zhongyuan Oilfield Company,Puyang 457000,China

出　　处：《Petroleum Exploration and Development》2021年第4期968-977,共10页石油勘探与开发（英文版）

基　　金：Supported by the Chongqing Technical Innovation and Application&Development Special Project(cstc2020jscx-msxmX0189)。

摘　　要：Permeability sensitivity to stress experiments were conducted on standard core samples taken from Wen 23 Gas Storage at multi-cycle injection and production conditions of the gas storage to study the change pattern of stress sensitivity of permeability.A method for calculating permeability under overburden pressure in the multi-cycle injection and production process was proposed,and the effect of stress sensitivity of reservoir permeability on gas well injectivity and productivity in UGS was analyzed.Retention rate of permeability decreased sharply first and then slowly with the increase of the UGS cycles.The stress sensitivity index of permeability decreased with the increase of cycle number of net stress variations in the increase process of net stress.The stress sensitivity index of permeability hardly changed with the increase of cycle number of net stress variations in the decrease process of net stress.With the increase of cycle number of net stress variation,the stress sensitivity index of permeability in the increase process of net stress approached that in the decrease process of net stress.The lower the reservoir permeability,the greater the irreversible permeability loss rate,the stronger the cyclic stress sensitivity,and the higher the stress sensitivity index of the reservoir,the stronger the reservoir stress sensitivity.The gas zones with permeability lower than 0.3’10-3 mm2 are not suitable as gas storage regions.Stress sensitivity of reservoir permeability has strong impact on gas well injectivity and productivity and mainly in the first few cycles.

关 键 词：gas storage rebuilt from gas reservoirs multi-cycle injection and production reservoir stress sensitivity injection and production capacity gas storage layer selection 

分 类 号：TE972.2[石油与天然气工程—石油机械设备]