聚合物驱后进一步提高采收率方法及其技术经济效果评价

EOR Technology after Polymer Flooding and it's Technical and Economic Evaluation

依据矿场实际需求,本文通过物理模拟驱油实验对聚合物驱后采用高浓度聚合物溶液(平均相对分子量M(下同)=2500×104,聚合物浓度CP=2.5g/L)、"碱/表面活性剂/聚合物"ASP(CP=2g/L,表面活性剂HAPS浓度CS=3g/L,碱浓度(CA=12g/L)、"表面活性剂/聚合物"SP(M=2500×104,CP=2g/L,非离子表面活性剂浓度CS=3g/L)、聚表剂溶液(CSp=2g/L)驱油效果进行了对比与评价。结果表明,在化学剂用量相同条件下,4种驱油体系均可以进一步提高原油采收率,采收率增幅在10.1%～22.9%之间。在化学剂费用相同条件下,采用单一高浓度聚合物段塞增油降水效果最好,最终采收率均高于4种驱油剂多段塞组合方式。多段塞组合方式中,"低黏度驱油体系+高黏度驱油体系"方式的增油效果好于"高黏度驱油体系+低黏度驱油体系"的增油效果。综合技术条件和经济效果两方面考虑,推荐聚合物驱后采用单一高浓度聚合物驱,采收率增幅预计为15%～18%。

based on the filed demands,the four displacement systems after polymer flooding,high-concentration polymer system（mean molecular weight M = 2500（104（hereinafter the same）,concentration of polymer CP = 2.5 g/L）,alkaline/surfactant/polymer ASP system（CP = 2 g/L,concentration of surfactant CS = 3 g/L,concentration of alcali CA = 12 g/L）,surfactant/polymer system（CP = 2 g/L,CS = 3 g/L） and polymeric surfactant system（Csp = 2 g/L）,were compared and evaluated by the core experiment.The results showed that all of the four kinds of displacing systems could enhance further oil recovery by 10.1% ～ 22.9% with the same slug size.Single high-concentration slug achieved the best final recovery at the same costs,which is higher than that multi-slug combination of the four kinds of displacing systems achieved.As for multi-slug combination,the final recovery of ＂the low viscosity oil displacement system ＋ the high viscosity oil displacement system＂was higher than that of ＂the high viscosity oil displacement system ＋ the low viscosity oil displacement system＂.Taking both technical conditions and economic effect into consideration,High-concentration polymer flooding was a recommended technology after polymer flooding,by which the recovery was expected to increase by 15% ～ 18%.