深层凝析气藏渗流规律及产能优化  

Flow law and productivity optimization of deep condensate gas reservoir

作　　者：苏玉亮[1] 师颖 李蕾[1] 陈征 郝永卯[1] SU Yuiang;SHI Ying;LI Lei;CHEN Zheng;HAO Yongmao(School of Petroleum Engineering,China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]中国石油大学(华东)石油工程学院,山东青岛266580

出　　处：《大庆石油地质与开发》2024年第5期149-157,共9页Petroleum Geology & Oilfield Development in Daqing

基　　金：中国石油天然气股份有限公司勘探开发研究院“十四五”后前瞻性重大科技项目“致密油可动用性评价及提高采收率机理研究”(2021DJ2022)。

摘　　要：深层凝析气田在世界气田开发中占有非常重要的地位,但随着生产过程中压力的不断下降,在压力到达露点压力时,会发生反凝析现象,导致气井产能下降。为了深入研究深层凝析气藏渗流规律,为后期产能优化提供参考,基于凝析油气体系在恒温条件下的反凝析渗流理论,建立了考虑凝析油污染条件下凝析气井动态优化的配产理论与方法,实现了气井合理配产由传统的静态计算转变为动态优化,并采用数值模拟方法对FS1井的合理产能进行分析。结果表明:随着压力的不断降低,凝析气藏产生凝析油的油藏范围进一步扩大,储层内渗流区会出现Ⅲ区—Ⅱ区—Ⅰ区的过渡区,将凝析气藏流体渗流划分为3个区域进行规律分析;产能优化后地层压力33.20 MPa条件下的合理生产制度为固定压力25.00 MPa生产,合理生产压差为8.20 MPa;在地层压力26.26 MPa条件下的合理生产制度为固定压力20.00 MPa生产,合理生产压差为6.26 MPa;在地层压力20.52 MPa条件下的合理生产制度为固定压力15.00 MPa生产,合理生产压差为5.52 MPa。7 a可提高储层凝析气采收率15.24百分点,提高凝析油采收率4.35百分点。研究成果可为优化深层凝析气藏气井工作制度提供参考。Deep condensate gas fields play an important role in the development of world gas fields.However,with pressure drops to dew point pressure during production process,retrograde condensation may occur,causing pro-ductivity decrease of gas wells.In order to study flow law of deep condensate gas reservoir so as to provide reference for productivity optimization in later stage,based on theory of retrograde condensate flow of condensate oil and gas system at constant temperature,production allocation theory and method are established for condensate gas well dy-namic optimization considering condensate oil contamination,realizing rational production allocation of gas well changed from traditional static calculation to dynamic optimization,and rational productivity of Well FS1 is ana-lyzed by numerical simulation.The results show that,with continuous pressure decrease,the range where conden-sate forming in condensate gas reservoir expands further andⅢ-Ⅱ-Ⅰtransition zone occurs in reservoir flow area.Fluid flow in condensate gas reservoir is divided into 3 areas for flow law analysis.After productivity optimization,the rational production system with formation pressure of 33.20 MPa is production with constant flow pressure of 25.00 MPa and the rational production pressure difference of 8.20 MPa,the rational production system with forma-tion pressure of 26.26 MPa is production with constant pressure of 20.00 MPa and the rational production pressure difference is 6.26 MPa,and the rational production system with formation pressure of 20.52 MPa is production with constant pressure of 15.00 MPa and the rational production pressure difference is 5.52 MPa.Condensate gas recov-ery factor is increased by 15.24 percentage points and condensate oil recovery factor is increased by 4.35 percentage points in 7 a.The research provides reference for optimizing working system of gas wells of deep condensate gas reservoirs.

关 键 词：深层凝析气藏 渗流规律 数值模拟 反凝析 动态优化 气井合理产能 

分 类 号：TE372[石油与天然气工程—油气田开发工程]