页岩气渗流规律测试条件研究  

Study on Experiment Conditions of Seepage Law of Marine Shale Gas

作　　者：朱维耀[1] 田巍[1,2] 高英[1] 邓佳[1] 张雪龄[3] 亓倩[1] 马千[1] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083 [2]中国石化中原油田石油勘探开发研究院,河南濮阳457001 [3]郑州轻工业学院能源与动力工程学院,河南郑州450002

出　　处：《天然气地球科学》2015年第6期1106-1112,共7页Natural Gas Geoscience

基　　金：国家重点基础研究发展计划("973")(编号:2013CB228002)资助

摘　　要：为了确定适于测试页岩气渗流规律的条件,实验室采用"压差—流量法"并使用真实气体针对中国南方海相页岩气储层岩心,分别按照定围压和定净围压2种方案开展研究,并分析围压施加方式对测试结果的影响。结果表明:无论是采用定围压方式还是定净围压方式实验,渗流曲线分为曲线段和拟线性段,并表现出非线性渗流的特征,其分界点分别为1MPa和1.3MPa,渗透率伤害率平均值分别为52.41%和40.56%,滑脱效应的影响也不相同。定围压方式下,注入压力变化通常会引起应力敏感,这与实际储层的开采过程不符,在较低有效应力下,滑脱效应的影响远远超过有效应力的影响;定净围压方式下,可测得完整的渗流规律曲线,用于模拟实际储层一段时期内的渗流状况,围压效应对气体渗流效果影响较小。综合分析认为定净围压方式测定页岩气渗流规律最好。Two methods to hold the experiment pressure were adopted to select the best condition for testing the gas seepage law of the marine shale gas core in south China,which are constant confining pressure mode and constant net confining pressure mode.The influence of different confining pressure mode on the experiment results was analyzed.And the best mode was selected under the actual formation condition.The conclusions show that gas flow rate increases with the injection pressure,whatever by the way of constant confining pressure or constant net confining pressure.The gas seepage law curve of the marine shale gas core in south China is nonlinear.The curve is divided into two regions including segment curve and pseudo linear curve,and the inflection points are 1MPa and 1.3MPa,respectively.The values of average permeability damage rate are 52.41% and 40.56%,respectively.The slip effect was affected by the confining pressure control mode.The change of injection pressure caused stress sensitivity,and the stress sensitivity effect was more obvious in the actual formation under the constant confining pressure.The influence of the slip effect on seepage law of marine shale gas is more than the stress sensitivity under the condition of low effective stress.A complete seepage law curve can be obtained,and a period of the seepage situation in the formation can be simulated under the constant net confining pressure.The results provide meaningful guidance for the gas field.The net confining pressure mode was also affected by the confining pressure,and the flow rate would decrease with the increase of the confining pressure.Above all,the net confining pressure is the best way to test the seepage law of the marine shale gas core in south China.

关 键 词：渗流规律 定围压 定净围压 滑脱效应 有效应力 围压效应 

分 类 号：TE37[石油与天然气工程—油气田开发工程]