致密储层CO_(2)驱动态裂缝网络水平井试井模型  

Dynamic fracture network well-testing model for horizontal wells in tight reservoirs with CO_(2) injection

作　　者：王质鹏 湛杰 张怡文 宁正福[1] 陈掌星 WANG Zhipeng;ZHAN Jie;ZHANG Yiwen;NING Zhengfu;CHEN Zhangxing(State Key Laboratory of Petroleum Resources and Exploration,China University of Petroleum(Beijing),Beijing 102249,China;School of Petroleum Engineering,Xi'an Shiyou University,Xi'an,Shaanxi 710065,China;Northwest Sichuan Gas Mine,Southwest Oil and Gas Field Company,PetroChina,Jiangyou,Sichuan 621700,China;Department of Chemical and Petroleum Engineering,University of Calgary,Alberta Calgary T2N 1N4,Canada)

机构地区：[1]中国石油大学(北京)石油资源与勘探国家重点实验室,北京102249 [2]西安石油大学石油工程学院,陕西西安710065 [3]中国石油西南油气田公司川西北气矿,四川江油621700 [4]University of Calgary,Department of Chemical and Petroleum Engineering,Alberta Calgary T2N 1N4

出　　处：《东北石油大学学报》2024年第5期102-116,I0008,共16页Journal of Northeast Petroleum University

基　　金：国家自然科学基金项目(51974330);国家自然科学基金青年项目(52004219);陕西省自然科学基金项目(2020JQ-781)。

摘　　要：为有效表征流体在致密储层CO_(2)驱动态裂缝网络系统的分区闭合及动态储容效应,以及反演动态裂缝网络特征参数,建立一种动态裂缝网络水平井试井模型,采用半解析方法、Laplace转换、动态裂缝特征函数、杜哈美原理和Stehfest数值反演求解试井模型,获得井底压力响应半解析解,绘制井底压力响应曲线,对动态裂缝闭合速度、井筒储集系数、动态裂缝网络半径和动态储容比进行敏感性分析。结果表明:考虑致密储层CO_(2)驱动态裂缝网络的压力图版与常规压力图版存在显著差异;井底压力响应曲线呈异常尖峰和额外双水平线特征,ψ′wD t D<0.5;动态裂缝闭合速度、动态裂缝网络半径及动态储容比对井底压力响应影响较大。动态裂缝网络水平井试井模型能有效定量表征致密储层长期注入CO_(2)的动态裂缝网络行为及非稳态渗流规律,为CO_(2)强化致密储层开发提供依据。In order to characterize the zonal closure and dynamic storativity effects of fluids in a dynamic fracture network system,and then invert the characteristic parameters of the dynamic fracture network,a dynamic fracture network well-testing model is established.The model is solved using semi-analytical method,Laplace transform,dynamic fracture conductivity function,dynamic storativity function,Duhamel's principle,and Stehfest numerical inversion theory to obtain a semi-analytical solution of the bottom-hole pressure response.The dynamic bottom-hole pressure response curve is plotted,and a sensitivity analysis is conducted on the dynamic fracture closure rate,wellbore storage coefficient,dynamic fracture network radius,and dynamic storage capacity ratio.Results show that the pressure plot considering the dynamic fracture network significantly differ from conventional pressure plots;the bottom-hole transient pressure curve exhibits abnormal peaks and additional double-horizontal line features(ψ′wD t D<0.5).The dynamic fracture closure rate,dynamic fracture network radius,and dynamic storativity ratio significantly impact the bottom-hole pressure response.Numerical simulations and field case study validate the reliability and practicality of the proposed model.This model effectively quantifies the unsteady-state seepage behavior and dynamic pressure response characteristics of long-term CO_(2) injection in tight reservoirs,providing theoretical basis and technical support for the development of CO_(2)-enhanced tight reservoir.

关 键 词：致密储层 CO_(2)驱 动态裂缝网络 分区闭合 动态储容 试井分析 

分 类 号：TE341[石油与天然气工程—油气田开发工程]