摘要
碳酸盐岩溶孔发育程度、注气速度是影响气水两相渗流的重要因素,也是目前碳酸盐岩气藏研究的重点。提出采用卷积算法构建岩心尺度的孔隙—溶孔双重介质孔隙网络模型的方法,分析了碳酸盐岩溶孔发育特征。与之前的方法相比,这个方法考虑了气体的压缩性、压力传播过程和时间等影响因素,建立了孔喉特征更为准确的孔隙—溶孔双重介质模型,并通过与实际岩心的气驱水渗流实验结果进行对比,验证了该方法的可靠性,从而能更加准确地从微观孔喉尺度反映注气速度对气水两相渗流的影响。研究结果表明,溶孔越发育,相渗曲线气水两相共渗区越宽,气水同流周期更长;同时注气压力与毛管力和黏性力间的平衡会影响气体波及效率,产生不同的气水空间分布情况、注气流量与注气压力。研究结果为碳酸盐岩气藏的开采提供了更精确的技术支撑和理论指导,对提高碳酸盐岩气藏的开发开采效率具有重要意义。
The objective of this study was to investigate the effects of the development degree of carbonate dissolved pores and gas injection velocity on the gas-water two-phase seepage.An interparticle-dissolved dual-pore network model was proposed using a convolution algorithm by considering the characteristics of carbonate karst pores.The proposed unsteady-state gas-water seepage model took the effects of gas compressibility and porescale pressure propagation into account,and it was validated by comparing the simulation results with the corederived gas-water two-phase seepage through unsteady-state gas flooding experiments,which comprehensively characterizes the pore-scale gas-water seepage flow in pore-scale modeling.The gas flooding procedure at different injection velocity was simulated by assuming different characteristics of dissolved pores in carbonates.The results indicated that the more developed dissolved pores can bring about a wider gas-water two-phase infiltration area and a longer gas-water co-flow period.Further,the competitive balancing between the gas injection pressure and the capillary and viscous forces could also impact gas sweeping efficiency,resulting in different gaswater spatial distributions,gas injection velocity and pressures.The results provided a deep technical and theoretical view of the gas production in carbonate reservoirs,which has important significance for improving the exploitation efficiency of carbonate reservoirs.
作者
杨鑫
李星甫
唐雁冰
戴隽成
戚涛
李闽
刘旭
YANG Xin;LI Xingfu;TANG Yanbing;DAI Juncheng;QI Tao;LI Min;LIU Xu(State Key Laboratory of Oil&Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu 610500,China;Exploration and Development Research Institute of Southwest Oil&Gasfield Company,PetroChina,Chengdu 610041,China)
出处
《天然气地球科学》
CAS
CSCD
北大核心
2023年第6期973-979,共7页
Natural Gas Geoscience
基金
国家自然科学基金青年科学基金项目“致密油储层岩石注水吞吐实验与多尺度动态网络模拟研究”(编号:41902157)
四川省自然科学基金青年科学基金项目“碳酸盐岩微孔隙—溶孔—裂缝三重介质孔隙网络建模与气水两相非稳态渗流模拟研究”(编号:2022NSFSC1118)
西南石油大学研究生科研创新基金项目(编号:2022KYCX027)联合资助.
关键词
碳酸盐岩
卷积
动态网络模拟
相对渗透率曲线
Carbonate rock
Convolution
Dynamic network simulation
Relative permeability curve
作者简介
杨鑫(1995-),男,四川南充人,博士研究生,主要从事油气渗流理论与应用研究.E-mail:22155411@qq.com;通信作者:李星甫(1995-)男,四川成都人,博士研究生,主要从事油气田开发研究.E-mail:2952746189@qq.com.
