微生物驱相对渗透率曲线测定

Measurement of relative permeability curve of cores in microbial flooding

为了进一步加强对微生物驱油过程及其后续水驱油的多相渗流规律和驱油机理的认识,采用稳态法成功测得了中一区Ng3油藏条件下(温度69℃和压力10 MPa)注微生物(AB-1菌和AB-2菌)前和注微生物后油水相对渗透率曲线.对比分析了注微生物前后岩心的束缚水饱和度、残余油饱和度、绝对渗透率和相对渗透率的变化特征.实验结果表明:与注微生物前相比,注微生物后岩心的束缚水饱和度增大,残余油饱和度明显减小,而岩心的绝对渗透率变化不大;等渗点明显右移,含水上升率明显减缓;两种菌均能较大幅度提高原油采收率,其中,AB-1菌提高采收率平均为8.7%,AB-2菌平均为9.2%.

The relative permeability curve of reservoir in microbial flooding is the significant basic data for the calculation and prediction of the exploitation indexes of the microbial flooding oilfields.In order to know the multi-phase seepage law and the flooding mechanism in the microbial flooding process and subsequent water flooding process,the oil-water relative permeability curves of Ng3 reservoir in Zhongyi area before and after the microbial flooding of bacteria AB-1 and bacteria AB-2 were measured under the reservoir condition of 69 ℃ and 10 MPa.The irreducible water saturation,the residual oil saturation,the absolute permeability and the relative permeability of cores before and after the microbial flooding are compared.The results show that,compared with before microbial flooding,the irreducible water saturation increases,the residual oil saturation decreases,the absolute permeability changes a little and the water saturation at equal permeability point obviously increase.The two kind strains of AB-1 and AB-2 all can enhance oil recovery factor,the microbial flooding of bacteria AB-1 can averagely enhances by 8.7% and AB-2 by 9.2%.