油藏高含水阶段CO_2水气交替驱研究及应用

Study and Application of Carbon Dioxide and Water Alternating Oil Displacement of High Water-cut Oil Reservoir

针对油田开发中后期含水率高难控制的问题,提出了CO2水气交替驱提高采收率的方法,采取室内驱替实验和矿场试验对驱油效果进行了评价。室内实验表明:岩心高含水阶段水气交替驱提高采收率效果明显,原油粘度和水气体积比对驱替效率的影响存在最佳区间。矿场试验表明:水气交替注入后单井日产油量提高22倍,含水率下降24.7%,阶段累积增油4721.2t,具有向其他高含水油田推广应用的价值。

In view of high water-cut in the middle and later periods of oilfield development, the carbon dioxide and water alternating oil displacement technology is put forward, and the oil displacement result of the technology is evaluated by laboratory experiments and field tests. The laboratory experiments show that, the result of the carbon dioxide and water alternating oil displacement technology is good, and there are optimal ranges of crude oil viscosity and water-to-carbon dioxide volume ratio. The field tests show that, the carbon dioxide and water alternating oil displacement technology can enhance the daily oil yield of single well 22 times, water cut can decrease by 24.7%, cumulative oil increasing is 4 721.2t. Therefore the technology is of value to apply and popularize.