摘要
为定量表征渗透压对致密砂岩储层渗吸置换效果的影响,基于毛管压力函数及渗透压方程,建立考虑渗透压的致密砂岩储层渗吸半解析数学模型,用于计算最终渗吸置换率、渗吸稳定时间、水相饱和度及矿化度的沿程分布等参数。对渗吸液矿化度、水相和油相最大相对渗透率、水相和油相相对渗透率系数、油水粘度比等参数进行敏感性分析,并与岩心实验结果进行拟合,以校正模型参数。研究结果表明:储层内流体与渗吸液矿化度差越大,渗吸置换作用越显著,渗透压主要影响渗吸置换中段位置;对渗吸效果影响从大到小依次为水相相对渗透率系数、水相最大相对渗透率、油水粘度比、油相相对渗透率系数、油相最大相对渗透率;油水粘度比对矿化度分布影响最为显著,水相相对渗透率系数及水相最大相对渗透率主要影响推进前缘段矿化度分布,油相相对渗透率系数及油相最大相对渗透率对矿化度分布几乎没有影响;模型渗吸置换率校正系数约为0.7;渗吸稳定时间校正系数与水相最大相对渗透率呈较好的线性相关。
In order to quantitatively characterize the effect of osmotic pressure on the imbibition displacement of the tight sandstone reservoir,a semi-analytical mathematic model for the imbibition of tight sandstone reservoir considering the os-motic pressure was established based on the capillary force function and the osmotic pressure equation.Based on the estab-lished model,the parameter sensitivity of imbibition salinity,maximum relative permeability of water phase and oil phase,relative permeability coefficient of water phase and oil phase and oil-water viscosity ratio were analyzed and compared with the core experiment results so as to correct the model parameters.The research indicates that the effect of imbibition dis-placement is more obvious when the salinity difference of reservoir fluid and imbibition fluid is larger,and the osmotic pres-sure mainly affects the middle position of the imbibition displacement.The order of parameters influencing the imbibition is as follows:the relative permeability coefficient of water phase>the maximum relative permeability of water phase>the ra-tio of oil-water viscosity>the relative permeability coefficient of oil phase>the maximum relative permeability of oil phase.The oil-water viscosity ratio has the most significant influence on the salinity distribution.The relative permeability coeffi-cient of water phase and maximum relative permeability of water phase mainly affect the salinity distribution of the propul-sion front.The relative permeability coefficient of oil phase and the maximum relative permeability of oil phase have almost no effect on the salinity distribution.The correction coefficient of the imbibition displacement model is about 0.7.The cor-rection coefficient of the stable imbibition time has a good linear correlation with the maximum relative permeability of wa-ter phase.
作者
刘雄
周德胜
师煜涵
李鸣
张争
LIU Xiong;ZHOU Desheng;SHI Yuhan;LI Ming;ZHANG Zheng(College of Petroleum Engineering,Xi’an Shiyou University,Xi’an City,Shaanxi Province,710065,China;Shaanxi Key Laboratory of Advanced Stimulation Technology for Oil&Gas Reservoirs,Xi’an City,Shaanxi Province,710065,China)
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2018年第5期93-98,共6页
Petroleum Geology and Recovery Efficiency
基金
国家科技重大专项"低渗透致密砂岩气藏压裂裂缝及参数优化"(2016ZX05050-009)
关键词
致密砂岩
渗透压
渗吸置换
半解析模型
矿化度
tight sandstone
osmotic pressure
imbibition displacement
semi-analytical model
salinity
作者简介
刘雄(1988—),男,湖南汨罗人,讲师,博士,从事低渗透油气藏开发研究。联系电话:(029)88212830,E-mail:lx06106232@163.com。;通讯作者:师煜涵(1993-),男,陕西西安人,在读硕士研究生。联系电话:18706887895,E-mail:szc0413@qq.com。
