高渗油藏注凝析气吞吐增产机理研究

Study on the Stimulation Mechanism of Condensate Gas Huff and Puff in High Permeable Reservoir

应用数值模拟方法研究了海外X油田注凝析气吞吐的增产机理。研究结果表明,注凝析气有效改善了井附近流体物性,即增加了井附近原油的泡点压力、膨胀系数,降低了原油黏度、原油密度、界面张力,进而达到增产目的。对于注凝析气吞吐井,周期累注气量越大,降黏半径越大,周期累产油量越高。注凝析气对油藏中流体物性的改变有效的降低了产出物的流体密度,进而延长了井的自喷产油期。从油田获取的资料表明,研究结果是符合实际油藏生产实际的。

Numerical simulation method is applied to study the stimulation mechanism of condensate gas huff and puff of overseas X-reservoir. The results show that condensate gas injection is effective in changing the fluid properties near the bottom of a well, namely it could increase bubble point pressure, the coefficient of expansion of crude oil, and reduce the viscosity, density, interfacial tension of the fluid. These changes stimulate the well accu- mulate production. For condensate gas huff and puff wells, the＇~＇increasing of cyclic aecumulate^t gas injection vol- ume could increase the visbreaking radius and cyclic accumulated oil production. The changing of reservoir fluid properties caused by gas injection is effective in reducing the effluence density, thereby extending the well flowing production period. Oilfield material shows that the research results can fit the actual well production data.