南海西部气田高温衰竭储层钻完井液技术研究及应用

HIGH TEMPERATURE AND DEPLETED RESERVOIR WELL DRILLING AND COMPLETION FLUID TECHNOLOGY

针对南海西部某气田调整井高温、储层衰竭、井深大、水平位移大、裸眼段长的特点,分析了气田开发的地质情况及技术难点,通过改进油基钻井液体系,对其配方进行滤失及封堵性能评价,并通过模拟高温衰竭储层钻井液侵污实验,获得了良好的封堵和滤失性能,3个小时高温高压滤失量只有2.6ml,储层保护效果好,返排压力仅1~2MPa,返排后岩心渗透率恢复值均在90%以上的改进型油基钻井液配方。现场应用配合连续油管氮气诱喷、不破胶完井液等合适的钻完井工艺技术,成功进行连续油管气举造负压反排和诱喷成功,投产产量超过了配产预期,成功的解决了高温衰竭储层井的钻完井难题,为类似海上和陆地高温衰竭储层油田的开发提供的基础,连续油管下深至6100m诱喷成功也创造了新的纪录。

For the high temperature and low pore pressure gas field, it is a key factor to select the right drilling and completion fluid. Challenges were met in the drilling and completion well: great well depth and open hole length, extend reach, high temperature and low pore pressure. According to Western South China Sea gas field feature, the new oil-base drilling fluid system was developed. Tests indicate that this system is low fluid loss and high blocking and three hours of high temperature and high pressure infiltration amount is only 2.6ml, and reservoir protection effect is good, flow back pressure only 1~2MPa. The permeability restoration is high up 90% in core experiments. Apply together with coiled tubing gas lifting and other technology high temperature and low pore pressure well drilling and completion problem is solved. This successful case provides reference for operators to develop similar high temperature and low pressure well completion all over the world and 6100 meters of coiled tubing has created a new record.