聚合物驱后三元复合驱油效果评价

THE EFFECTIVENESS OF ASP FLOOD IN POLYMER-FLOODED RESERVOIRS OF DAQING

本文针对大庆油田仍残留有大量原油的聚合物驱后油藏 ,采用室内岩心驱油方法 ,对进一步提高采收率的 3种方法进行了实验评价。实验数据表明 ,聚合物驱后采用碱 /表面活性剂 /聚合物三元复合体系、碱 /表面活性剂 /交联聚合物三元复合体系 (交联三元复合体系 )及交联聚合物体系 (胶态分散凝胶 ,CDG)段塞加三元复合体系段塞组合 ,都可以在一定程度上进一步提高原油采收率 ,其中交联三元复合体系驱油效果最好。已有经济上可行的交联三元复合体系配方。

Three EOR methods are evaluated on artificial heterogeneous models(cores)after polymer flooding at different polymer use levels in mg/L×PV:570,800,1 000. These postpolymer flood EOR methods are:①plain NaOH/petroleum sulfonate/polymer ASP flood;② crosslinked by AlCit polymer solution plug+plain ASP solution plug;③ NaOH/petroleum sulfonate/crosslinked by AlCit polymer flood. It is shown that the lower the polymer use level in the initial polymer flooding the lower the oil recovery enhancement by the polymer flood is and the higher the oil recovery enhancement by the successive postpolymer chemical flood is; the three EOR methods are arranged according to their effectiveness in order: ③>①>②. An economical crosslinked ASP flooding solution is presented. The experimental evaluation is performed for use in polymer flooded reservoirs of Daqing (45℃).