摘要
随着水平井在有水气藏开发中的大量应用,发现水平井一方面能够提高气井的单井产能、降低气井生产压差、延长气井稳产期,而另一方面,水平气井见水后地层能量不足时井筒携液困难,尤其高产气井采用大油管时其携液能力更低,对生产影响严重。因此,对于具有边水的水平气井,如何有效、准确地监测并预报气井或气藏边水水侵前缘,一直是气田开发过程中的一大难题。为此,以气-水两相不稳定渗流模型为基础,采用与解析解具有相同渗流数学模型、以数值解为求解结果的数值试井为手段,对边水推进过程中水平气井压力恢复试井双对数曲线的变化特征进行了深入研究,形成了水平气井边水水侵前缘的定量诊断方法,并在四川盆地某气藏开展了现场应用。研究结果表明:①应用不稳定试井分析来定量诊断水平井边水水侵前缘的方法是可行并且准确的。②明确了井型对定量诊断边水水侵前缘的影响。即对直井,实际水侵前缘与解析反演计算的水侵前缘结果相近;对水平井,当实际水侵前缘距井筒距离大于气井有效水平段长度时,实际水侵前缘与计算水侵前缘结果相近;而当实际水侵前缘距井筒距离接近或小于气井有效水平段长度时,计算水侵前缘与实际水侵前缘存在一定偏差,需要对计算水侵前缘作校正,并提出了相应校正方法。③确定水平气井水侵前缘定量诊断方法的适用范围是非裂缝窜进型边水入侵气井。④应用实例验证了方法准确实用,表明在非裂缝水窜型边水入侵过程中,通过本方法能有效监测边水水侵前缘,进而计算其水体推进速度,分析气井不同阶段的水侵特征及变化规律。⑤通过定期压力恢复试井监测其水侵前缘,分析水侵特征及变化规律,适时调整气井与气藏配产,可有效延长气井无水采气期与气藏稳产期,提高气藏整体开发效果。
With the extensive application of horizontal wells to development of gas reservoirs with water,it has been found that horizontal-well development mode can effectively increase the productivity,reduce the production pressure difference,and prolong the stable production period.However,when formation energy is inadequate after water breakthrough,it is difficult to carry liquid in the wellbore,especially for many high-yield gas wells with large tubing,which has a serious impact on production.How to effectively and accurately monitor and predict the water invasion front in a gas well or a gas reservoir with edge water has always been a challenge.So,based on one gas-water two-phase unsteady flow model,another mathematical model with the same flow as the analytical solution was used and the numerical well test with numerical solution as the result was conducted to deeply analyze the variation on log-log curve of build-up well test in horizontal gas well during edge water advancing.In addition,a quantitative diagnosis method of water invasion front for horizontal gas wells was formed.And this method has been applied to one gas reservoir in Sichuan Basin.Results show that(1)the method of quantitative diagnosing the edge water invasion front in horizontal wells through unstable well test analysis is feasible and accurate;(2)the influence of well type on the quantitative diagnosis is made clear.For vertical wells,the actual water invasion front is similar to that calculated by analytical inversion.For horizontal wells,when the distance between the actual water invasion front and the wellbore is greater than the length of effective horizontal interval,the actual water invasion front is similar to the calculated one;when the distance is close to or less than the length of the effective horizontal interval,there is a certain deviation between the calculated and the actual ones,and the calculated water invasion front needs to be corrected,and some corresponding correction method is also proposed;(3)this quantitative diagnosis m
作者
王娟
冯曦
李玥洋
邓惠
戚涛
袁山
姜艺
Wang Juan;Feng Xi;Li Yueyang;Deng Hui;Qi Tao;Yuan Shan;Jiang Yi(Exploration and Development Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610041,China)
出处
《天然气勘探与开发》
2022年第2期39-48,共10页
Natural Gas Exploration and Development
关键词
不稳定试井
压力恢复试井
水平井
水侵前缘
定量诊断
气-水两相渗流
数值试井
Unstable well test
Build-up well test
Horizontal well
Water invasion front
Quantitative diagnosis
Gas-water two-phase flow
Numerical well test
