低渗气藏岩心孔隙结构与气水流动规律  

Pore structure and gas-water flow law of low permeability gas reservoir core

作　　者：胡勇[1] 朱华银[1] 姜文利[2] 杨小芳[3] 付大其[4] 

机构地区：[1]中国石油勘探开发研究院廊坊分院,河北廊坊065007 [2]国土资源部油气资源战略研究中心,北京100812 [3]天津大港油田钻采工艺研究院采油技术中心,天津300280 [4]大庆石油学院石油工程学院,黑龙江大庆163318

出　　处：《辽宁工程技术大学学报（自然科学版）》2009年第S1期35-37,共3页Journal of Liaoning Technical University (Natural Science)

基　　金：中石油股份公司重大资助项目(2008B-1101)

摘　　要：为了搞清楚低渗气藏岩心孔隙结构及其对气水渗流的影响,综合物性测试、核磁共振、压汞、气驱水等实验技术,研究了某低渗气藏岩心的孔隙类型、孔隙结构、水的赋存状态以及气水流动特征。研究表明:该气藏岩心孔隙类型以粒间溶孔为主,孔喉半径细小,排驱压力大,分选较差,岩心渗透性受孔喉半径大小控制;低渗气藏岩心孔喉中含水使气体流动产生启动压力,气驱压力低于启动压力时,气相流量为零,不能有效流动;水在低渗岩心孔隙中以可动水和残余水两种形式赋存,在气驱实验过程中,随着气驱压力增加,气体开始流动,水的赋存状态会发生改变,岩心孔隙中的水会被逐渐驱出,岩心渗透性能得到改善,气相流量也会增加。所以,对于低渗含水气层,确定合理的生产压差控制气水渗流是有效开发的关键。该研究成果对低渗气藏合理开发具有一定指导意义。The problem is not clear that the pore structure and its effect on the gas-water flowing in low permeability gas reservoir core,so the experimental techniques are used such as physical property test,NMR,Mercury penetration,gas drive water,and so on,to research the core’s pore types,pore structure,water’s occurrence modes in the pore throat and the gas-water flow law in cores.The results show that most of the core’s pore is intergranular pore,the radius of pore throat is tiny,valve pressure is big,gradation is bad and the permeability is controlled by the radius of pore throat.When the core is fully saturated by water,there is an actuating pressure for gas flow.When the gas drive pressure is lower than the actuating pressure,then the gas can not flow freely.The water in the core occurrence with two types: movable water and residual water,when the drive pressure is increasing during gas flooding,the water’s occurrence mode will change,part of the water will be driven out,the permeability will be enhanced and the gas flow will increase.So,for low permeability containing water gas layer,it is one of the key factors to decide appropriate producing pressure drop to control the gas-water flow.The result is important for development of low permeability gas reservoir.

关 键 词：低渗气藏 孔隙结构 气水渗流 岩心实验 

分 类 号：P618.13[天文地球—矿床学]