套保油田降粘剂驱油室内实验研究

THE LABORATORY STUDY OF OIL-DISPLACEMENT WITH VISCOSITY REDUCTION AGENT AT TAOBAO OILFIELD

化学辅助降粘是提高稠油采收率的重要方法之一。针对套保油田储层胶结松、易出砂且隔层薄的地质特点和稠油的特定物化性质,以稠油乳状液的稳定性、稠油乳状液粘度及稠油降粘剂的界面张力为评价手段,对三种不同类型的降粘剂进行初步筛选。同时以采收率作为评价手段,进行室内物理模拟驱油实验。结果表明,在相同的实验条件下,选用脂肪醇聚氧乙烯醚羧酸盐降粘剂时所形成乳状液的稳定性、降粘作用、界面张力达到最佳,当其添加量为0.5%、注入速度为1.0 mL/min时,岩心原油最终采收率达到96.35%。

Viscosity reduction of heavy oil with auxiliary chemicals is one of the main methods of EOR. Based on the geologic characteristics of the oil reservoir in Taobao oilfield, such as poor cementation, easy sand production and thin barrier, and the physicochemical properties of heavy oil, three various viscosity reduction agents were tested to compare the stability, viscosity and interracial tension of heavy oil with various chemicals. Test for physical simulation flooding was carried out in lab to observe the oil recovery rate. The results showed that under the same testing conditions,viscosity reduction agent A, a carboxylate polyoxyethylenated alcohol, exhibited the best stability,viscosity reduction function and interracial tension of the heavy oil emulsion. When the added dosage of agent A was 0. 5% and the injection rate was 1.0 mL/min,the final oil recovery rate reached 96.35%.