东海西湖底水薄油气藏开发策略研究及实践

Development Strategy Study and Practice of Thin Bottom-water Oil and Gas Reservoirs in Xihu Sag,East China Sea

实现均衡水侵是减缓底水薄油气藏水侵速度、延长无水采气期、提高开发效果的关键。该文利用机理模型对底水薄油气藏开发策略进行研究,主要包括井型、水平井长度、完井方式、避水高度及采速等因素,并对东海西湖开发实践进行总结。研究表明:水平井+变密度定向射孔是开发底水薄油气藏的关键技术;控制采油气速度至关重要;水平井长度及避水高度对开发效果具有显著影响。合理的开发策略可延长无水期3年,提高采收率5%。东海西湖成功的开发实践可为该类油气藏高效开发提供一定的借鉴。

Achieving balanced water invasion is the key to slowing down the water invasion rate of thin bottom-water oil and gas reservoirs,prolonging the water-free gas production period and improving the development effect.In this paper,the mechanism model is used to study the development strategy of thin bottom-water oil and gas reservoirs,including well type,horizontal well length,completion method,water avoidance height and production rate.Also the development practice in Xihu Sag of East China Sea is summarized.The study shows that horizontal wells combined with variable density oriented perforation is the key technology to develop thin bottom-water oil and gas reservoirs.It is very important to control the speed of oil and gas production.The length of horizontal well and the height of water avoidance have a significant impact on the development effect.A reasonable development strategy can extend the water-free period for 3 years and increase the recovery rate by 5%.The successful development practices in Xihu Sag of East China Sea can provide some reference for the efficient development of such reservoirs.