渤海稠油油藏N2泡沫复合驱室内评价

Laboratory Evaluation on N2 Foam Flooding System Used in Viscous Crude Reservoir of Bohai Oilfield

针对注水开发海上稠油油藏存在油井含水上升快,油井原油产量下降快,采出程度低等问题,研究了采用N2泡沫复合驱提高采收率技术的可行性。通过室内试验优选出复合泡沫剂配方,即2000 mg/L XM-3C+1800 mg/L HAPAM;考察了N2泡沫注入量和气液比对原油采收率的影响。驱油试验结果表明,采收率随着N2泡沫注入量的增加而增大,当注入量增加到0.4 PV时,采收率的增幅趋于平缓;采收率随气液比的增加而先增大后减小,当气液体积比为3∶1时,采收率达到最大值37.12%。

In consideration of the problems of the rapid increase of water cut of oil wells,the rapid decline of crude oil production of oil wells,and low recovery percent of reserves,etc.,the feasibility of using N2 foam flooding system to enhanced oil recovery was studied.The formulation of a composite foaming agent,i.e.2000 mg/L XM-3 C+1800 mg/L HAPAM,was identified through laboratory test,and the effects of N2 foam injection rate and the gas-to-liquid ratio were studied.The results of oil displacement test have shown that the recovery efficiency increases as the N2 foam injection volume increases with the increase of recovery efficiency flattening out when the injection volume increases to 0.4 PV and that the recovery efficiency increases and then decreases as the gas-to-liquid ratio increases with the recovery efficiency reaching the maximum value of 37.12%when the gas-to-liquid ratio is 3:1.