为了探索非均质稀油油层聚合物驱油后不同调剖蒸汽驱对原油采收率的影响,用大庆油田第三采油厂天然圆柱状岩心和模拟地层油,经过45℃环境下的水驱和聚驱后,在双温度场(油层和注入介质)条件下进行了变异系数为0.72的非均质油层(三管并联)常规及调剖蒸汽驱实验研究.结果表明:按照调剖后各层总渗流阻力相等的原则进行聚丙烯酰胺冻胶体系分层调剖后,其蒸汽驱提高采收率幅度为28.93％,而笼统调剖后的驱替效果比不调剖时还差;采用SD-3活性剂与聚丙烯酰胺冻胶体系复配调剖蒸汽驱效果为所有调剖中最好的,其蒸汽驱采收率达到30.58％,高于单纯普通冻胶体系调剖1.65个百分点,油汽比达到0.155;虽然分层复配调剖后蒸汽驱采收率提高幅度可接近均质油层的蒸汽驱采收率提高幅度,但其油汽比较均质油层的低0.034.非均质储层蒸汽驱采收率和油汽比实验,可为进一步提高原油采收率提供依据.%In order to explore the effects of different profile-control steam floodings after polymer flooding on the oil recovery in heterogeneous low-viscosity oil layers, using the natural cylindrical cores and simulating reservoir oil from Third Oil Production Factory of Daqing Oilfield, after both water and polymer floodings under 45 ℃, the conventional (three paralleled cores) and profile-control steam flooding experiments have been made for heterogeneous oil layers with 0. 72 variation coefficient under the conditions of two temperature fields ( oil layer and injection medium ). The results show that after PAM frozen glue separated layer profile control the steam flooding recovery is enhanced 28. 93% according to the equal principle of the total filtrational resistance for each layer after profile control. To our disappointment, the effects of commingled profile control is rather worse than those of non-profile control ; and the effects of profile-control steam flooding by means of compounded distribution steam flooding both SD-3 active agent and PAM frozen glue system are most favorite in all profile controls, the recovery rate has reached 30. 58% , 1. 65 % higher than pure frozen glue profile system, and furthermore the oil-steam ratio is up to 0. 155 ;although the recovery of the former is similar to that of homogeneous oil layer, the oil-steam ratio of is 0. 034 lower than that of the latter. The experiments of both steam-flooding EOR and oil-steam ratio for heterogeneous reservoirs can provide an evidence for further EOR.
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