摘要
压裂可提高油气藏单井产量是普遍认同的观点,但是否能降低凝析气藏反凝析伤害的程度亟待深入探讨。采用室内岩心实验、单井数值模拟方法,对比分析了压裂前后反凝析对气相渗透率、近井区反凝析油饱和度、单井产量及采收率的影响。研究表明,压后反凝析伤害程度更加严重、伤害时机更早,但裂缝降低了凝析油临界流动饱和度。衰竭过程中,压后气相的有效渗透率始终大于压前值,气相流动能力大幅度提高。压后单井初期采气速度高、地层压力降低快、反凝析伤害更加突出;与压前比较,凝析油采收率降低3.48%、天然气采收率提高6.6%。因此,压裂并不能有效降低反凝析伤害的程度,但可提高气相流动能力,从而提高凝析气井的天然气产量。
Generally speaking,the fracturing can improve the reservoir single well production,however,whether it can reduce the retrograde condensation damage in gas condensate wells or not is urgent to be discussed further.By adopting the indoor core labora-tory and single well numerical simulation method,we analyze the impacts of retrograde condensation on the gas phase permeability,the retrograde gas condensate saturation near the wellbore zone,the single well production and the recovery ratio before and after fracturing.The research shows that,after fracturing,the retrograde condensation damage is more serious and the damage time is ear-lier.However,the fractures reduce the condensate oil critical flow saturation.In the process of the depletion exploitation,the effec-tive permeability value of the fractured gas phase is always larger than the value before fracturing.In addition,the gas phase flow ability increases substantially.After fracturing,the gas recovery speed of the single well is fast,the formation pressure reduces rap-idly and the retrograde condensation damage is more serious.Furthermore,the recovery ratio of the condensate oil reduces by 3.48%and the recovery ratio of the natural gas improves by 6.6%.Accordingly,it concludes that,fracturing can’t effectively re-duce the degree of the retrograde condensation damage,but it can improve the flow ability of the gas phase and the gas production of the gas condensate wells.
作者
王少飞
汪周华
张雅玲
郭平
焦廷奎
杜建芬
Wang Shaofei;Wang Zhouhua;Zhang Yaling;Guo Ping;Jiao Tingkui;Du Jianfen(Exploration and Development Research Institute and National Engineering Laboratory for Exploration and Development of Low Permeability Oil and Gas Field,PetroChina Changqing Oil and Gas Field Company,Xi’an,Shaanxi 710018,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China)
出处
《油气藏评价与开发》
CSCD
2018年第2期30-34,共5页
Petroleum Reservoir Evaluation and Development
基金
低渗透油气田勘探开发国家工程实验室开放课题"苏里格气田相图建立及凝析
反凝析现象对气田开发的影响"(技2016-01)
关键词
凝析气藏
反凝析
压裂
全直径岩心
数值模拟
condensate gas reservoir
retrograde condensation
fracturing
full diameter core
numerical simulation
