高孔高渗强边水油藏氮气泡沫驱提高采收率研究

Enhanced oil recovery by nitrogen foam flooding technology for high porosity and high permeability reservoir with strong edge water

春光油田高孔高渗强边水油藏在开发中后期进入了高含水阶段,剩余油在构造顶部及边缘富集,仅靠边水能量驱替效果不理想。本文通过填砂管实验分析氮气泡沫驱提高采收率机理及效果,并使用数值模拟方法进行氮气泡沫驱提高采收率对策研究,提出排8-40区块氮气泡沫驱优化方案,并预测提高采收率效果。结果表明:氮气泡沫具有“堵高不堵低”、“堵水不堵油”的选择性封堵特征,能有效改善非均质油藏的驱替状况,起到调剖堵水的效果。根据数值模拟结果实施氮气泡沫驱技术对策,预测2年内氮气泡沫驱方案相比原方案增油2116 t,采收率提高1.51%。

The high porosity,high permeability and strong edge water reservoir in Chunguang oilfield has entered the high water cut stage in the middle and late stage of development.The remaining oil is enriched at the top and edge of the structure,and the displacement effect is not ideal only by edge water energy.This paper analyzes the mechanism and effect of the enhanced oil recovery through nitrogen foam flooding experiments in sand-screen pipe.According the numerical simulation of nitrogen foam flooding,the technical policy of enhanced oil recovery was put forward for the parameter optimization plan of nitrogen foam flooding.Then it can evaluate the effect of nitrogen foam flooding to enhance the recovery.Studies found that nitrogen foam has the characteristics of"blocking high but not low"and"blocking water but not oil",thus effectively improving the displacement recovery efficiency of heterogeneous reservoirs.It also plays a role in profile control and water shutoff for flooded wells.According of the nitrogen foam flooding technology carried out by numerical simulation result,it is predicted that after two years oil production of the optimized program will increase by 2116 t compared with the original program,and the recovery rate will increase by 1.51%.