油藏润湿性对采收率影响的实验研究

为了研究润湿性对油藏水驱采收率的影响,实验选用了低、中、高三种不同渗透率的露头砂岩心,利用甲基硅油、模拟油等化学剂将其润湿性由亲水状态改为中性和亲油状态,通过岩心驱替实验,研究了不同润湿性对水驱油采收率的影响。实验表明,岩心的润湿性由亲水和亲油状态转向中性润湿后,最大限度降低了多孔介质中毛管渗流阻力,从而提高了水驱效果。本实验条件下,建议将水驱后期油藏的润湿性由亲水或亲油状态转为中性润湿,则有利于水驱效率的大幅度提高。

The Effects of Wettability on Oil Recovery Efficiency

For achieving a better understanding of the effects of wettability on the oil recovery, the core displacement experiments were carried out . By using outcrop man -- made cores with low , middle and high permeability , and converting core＇s wettability from water--wet and oil--wet to intermediate wet, the oil recovery efficiency after water flooding on the cores was studied. The results show that converting core＇s wettability from water wet and oil--wet to intermediate wet is favorable to decreasing maximumly the capillary force as a resistance force in reservoir pores, and enhancing water displacement effects. So the suggestion that the wettability of water--wet and oil--wet should be changed into intermediate wet on the experimental condition.