文昌某区低渗凝析气田循环注气可行性研究

Feasibility Study on Circulating Gas Injection of Low Permeability Condensate Gas Field in Wenchang Area

高达 聂法健 陈健 谢艾冬 王艳平 丁纾琪

GAO Da NIE Fajian CHEN Jian XIE Aidong WANG Yanping DING Shuqi

中海石油（中国）有限公司海南分公司，海南海口　570312 长江大学石油工程学院，湖北武汉　430100 中国石油化工股份有限公司华北油气分公司采油一厂，陕西咸阳　712000 北京印刷学院设计艺术学院，北京　102600

CNOOC Hainan Branch, Haikou, Hainan 570312, China School of Petroleum Engineering, Yangtze University, Wuhan, Hubei 430100, China No.1 Oil Production Plant of North China Oil and Gas Company, SINOPEC, Xianyang, Shaanxi 712000, China Beijing Institute of Graphic Arts and Design, Beijing, 102600, China

针对文昌某区低渗凝析气藏反凝析现象严重、边水水侵加剧、产量递减快等问题，系统地开展了循环注气提高凝析气藏采收率可行性研究，通过PVT、岩心驱替等实验手段，明确了注入不同CO2含量干气的提高采收率机理，应用组分数值模拟方法，明晰了不同开发方式下的驱替特征，深度优化了注入方式、注气速度等关键注采参数。研究显示，目标区可通过循环注气大幅改善开发效果，注入富含CO2的干气可以有效抑制反凝析及边水水侵，提高凝析油气采收率。预计循环注气10年，凝析气采出程度达57.65%，凝析油采出程度达36.88%，与衰竭开发相比分别提高14.63%和10.17%，有效延长气藏经济寿命期。该成果为区块的高效开发提供了技术支撑，对类似的凝析气藏开发也具有重要指导意义。

To solve the problems of serious retrograde condensation phenomenon, intensified water intrusion of edge water and rapid production decline, feasibility study on enhancing condensate gas reservoir recovery has been systematically carried out by circulating gas injection. Through the PVT and core displacement experiment methods, we make clear that the recovery can be enhenced by injecting dry gas with different CO2 contents. By means of components numerical simulation method, the displacement characteristics under different development modes were clarified and the key injection-production parameters such as injection mode and gas injection rate were deeply optimized . The research shows that the development effect of the target area can be greatly improved by circulating gas injection. Injecting dry gas rich in CO2 can effectively inhibit retrocondensation and edge water invasion, and improve the recovery of condensate oil and gas. It is estimated that the recovery degree of condensate gas and condensate oil can reach 57.65% and 36.88% in 10 years of circulating gas injection. Compared with depletion development, it increases 14.63% and 10.17% respectively, and effectively prolongs the economic life of gas reservoir. The results provide technical support for the efficient development of this block and have important guiding significance for the development of similar condensate gas reservoirs.

https://doi.org/10.3969/j.issn.1008-2336.2022.02.042