低压凝析气藏与CO2气藏联合开发试验研究

Experimental research on joint development of low pressure condensate gas reservoir with CO2 gas reservoir

针对富含凝析油的小断块凝析气藏衰竭式开发过程中凝析油采收率偏低的问题,结合研究区内凝析油气和CO2资源分布特点,提出了低压凝析气藏和高含CO2气藏联合开发的思路。选取研究区内低压凝析气藏A气藏和高含CO2的B气藏进行联合开发模拟试验,通过数值模拟分析,开展了注采气井网优化、注入气组分设计、注气速度指标优选等不同开发方案下凝析油采出程度的对比研究。研究结果表明,采用联合开发方案后,预计凝析油采收率在原采出程度的基础上可提高20.46%。该设计理念既解决了因环保要求导致高含CO2气藏暂闭无法开发利用的问题,同时提出了一项对衰竭式开发后低压凝析气藏提高凝析油采收率的技术方法。

Aiming at the problem of low condensate oil recovery during the depletion development of small fault-block condensate gas reservoirs rich in condensate oil,combined with the distribution characteristics of condensate oil and gas and CO2 resources in the research area,the idea of joint development of low-pressure condensate gas reservoirs and gas reservoirs with rich CO2 was put forward.Low-pressure condensate gas reservoir A and high CO2 content gas reservoir B in the research area were selected to conduct simulation tests of joint development.Through numerical simulation analysis,comparative studies on the recovery degree of condensate oil under different development programs,such as the optimization of gas injection and production well patterns,injected gas component design and the optimization of gas injection speed indicators were carried out.It is showed that the joint development has remarkable effect in increasing the expected condensate oil recovery by 20.46%on the basis of the original recovery level.The design concept not only solves the problem of temporary closure of gas reservoirs with rich CO2 that cannot be developed and utilized due to environmental protection requirements,but also provides a technical method for improving the condensate oil recovery of the low-pressure condensate reservoir after depletion development.