三区复合凝析气藏多分支水平井压力动态特征  

Pressure-transient characteristics of multilateral horizontal well in three-region composite condensate gas reservoir

作　　者：姜瑞忠[1] 沈泽阳 崔永正 潘红[2] 张伟 张福蕾 JIANG Ruizhong;SHEN Zeyang;CUI Yongzheng;PAN Hong;ZHANG Wei;ZHANG Fulei(School of Petroleum Engineering,China University of Petroleum(East China),Qingdao,Shandong 266580,China;Research Institute of Oil Production Technology,PetroChina Dagang Oilfield Company,Tianjin 300280,China;The Pennsylvania State University,University Park,PA 16802,USA)

机构地区：[1]中国石油大学(华东)石油工程学院,山东青岛266580 [2]中国石油大港油田分公司采油工艺研究院,天津300280 [3]The Pennsylvania State University,University Park,PA 16802,USA

出　　处：《东北石油大学学报》2019年第4期116-124,I0008,共10页Journal of Northeast Petroleum University

基　　金：国家科技重大专项(2016ZX05027-004-004);国家自然科学基金项目(51574265)

摘　　要：钻井技术的发展使多分支水平井应用于海上凝析气藏开发。根据凝析气藏开采过程中的相变特征,将气藏划分为3个区:Ⅰ区为油气同流区,Ⅱ区为气体流动、油不流动的过渡区,Ⅲ区为纯气区。建立三区复合凝析气藏多分支水平井的解析模型,采用点源函数、Fourier有限余弦积分变换、Green函数等方法求解模型,利用MATLAB软件绘制井底压力特征曲线,分析凝析气藏多分支水平井的渗流规律,对相关参数进行敏感性分析。结果表明:凝析气藏多分支水平井的渗流过程划分为9个阶段;应力敏感效应使第二径向流阶段后的压力特征曲线逐渐上翘;分支井长度增加,分支井线性流持续时间变长;分支井间距减小,两分支井间的压力波相互干扰,导致第二径向流水平段缩短;分支井数量减少使早期的压力特征曲线向上偏移;相邻两区流度比越接近1,曲线后期上移越明显;区域半径影响径向流阶段持续时间。该模型能更准确地模拟凝析气藏多分支水平井的生产动态,为凝析气藏开发提供指导。With the continuous development of drilling technology,multi-branch horizontal wells have been used in the development of offshore condensate gas reservoirs.According to the characteristics of phase transition in the process of condensate gas reservoir exploitation,this model consists of three regions:region I is the oil and gas co-current region,region II is a transition zone where gas flow and oil does not flow,and region III is the pure gas region.This paper presents an analytical model for multilateral horizontal wells in three region composite condensate gas reservoir.The model was solved by point source solution,cosine transform,Green function and other methods.Then,the inclined well test curves were obtained by using MATLAB,the seepage law of multi-branch horizontal wells in condensate gas reservoirs was analyzed and sensitivity analysis was conducted.The study shows that the seepage process of multi-branch horizontal wells in condensate gas reservoirs is divided into 9 stages.The pressure sensitive effect causes the test curve in the subsequent phase of the second radial flow segment to gradually rise.The length of the branch well increases,and the linear flow duration of the branch well becomes longer.When the intervals between the branch wells is reduced,the pressure waves between the two branches will interfere with each other,resulting in a shortening of the horizontal section of the second radial flow.A decrease in the number of branch wells will cause the early well test curve to shift upward.The ratio of the flow rate in the adjacent two zones is larger and closer to 1,the overall shift of the curve later.In addition,the radius of the zone affects the duration of the radial flow phase of the zone.This model can more accurately simulate the production dynamics of multi-lateral wells in condensate gas reservoirs,and can provide some theoretical guidance for the development of condensate gas reservoirs.

关 键 词：凝析气藏 三区复合 多分支水平井 解析解 井底压力 渗流规律 敏感性分析 

分 类 号：TE372[石油与天然气工程—油气田开发工程]