【摘要】 利用国产露头砂岩岩心,研究了亲水条件下,无机盐对岩心采用表面活性剂溶液进行自发渗吸驱油的规律和采收率的影响。研究表明,无机盐对亲水砂岩的化学渗吸行为和最终渗吸采收率存在一定影响,具体表现为表面活性剂溶液中添加Ca2+或SO42-后,随着2价离子浓度增加,采收率先小幅下降后快速增加,采收率与2价离子浓度呈类似"∪"型变化特征,较高浓度的2价离子对化学渗吸具有一定促进作用。添加适量的Ca2+或SO42-,可以促进岩心的化学渗吸,从而提高岩心渗吸采收率。更多还原

【Abstract】 The effect of inorganic salt on spontaneous imbibition and recovery factor of surfactant flooding has been studied under water-wet condition with outcrop sandstone cores. It shows that the inorganic salt has certain effect on the chemical imbibition behavior and ultimate recovery of water-wet sandstone. After adding Ca2+ or SO42-into surfactant solution,the concentration of 2-valence ions increases,the recovery factor slightly decreases at first then increases rapidly. The relationship between the recovery factor and the concentration of 2-valence ions shows "U" shape feature. The 2-valence ions of higher concentration can accelerate chemical imbibition. Therefore appropriate amount of Ca2+ or SO42-can improve chemical imbibition and recovery factor of core.更多还原