产气产酸菌提高低渗透油藏原油采收率的应用基础研究

Study on Application of Gas and Acid Producing Bacteria for Enhanced Oil Recovery of Low Permeability Reservoirs

考察了所筛选的产气产酸菌KB提高低渗透油藏原油采收率的应用潜力。糖蜜发酵实验中KB菌代谢产生大量气体和有机酸,其中有机酸主要为乙酸。利用饥饿处理法制备超小KB菌,处理后KB菌只有新鲜培养菌株大小的四分之一左右,且保留较高活性。利用微观仿真透明模型观察KB菌对残余油的作用,结果表明KB菌可在油相边缘及附近的水相中增殖,并朝着残余油的方向运动。岩芯实验表明,KB菌可以有效地提高低渗透油藏的原油采收率,具有对低渗透油藏解堵的应用潜力;饥饿法处理得到的超小KB菌可以更好地降低低渗岩芯的阻滞作用,在应用过程中可以被推进到更深的地层,进而更好地发挥作用。

The screened strain KB producing gas and acid for enhanced oil recovery of low permeability reservoirs was studied. Strain KB produced organic acids which were mainly acetic acid. The ultramicrobacteria of KB with high activity was prepared by starvation treatment and its size was only about a quarter of that of the fresh one. Strain KB could proliferate in the oil-water phase and move toward the oil phase which was observed from the etched-glass micromodels. Core experiments proved strain KB could effectively enhance oil recovery of low permeability reservoirs with application potential to remove plugging, and the starved cells of ultramicro bacteria KB had better effect for penetrating rock pore spaces during the injection. and sand matrices very readily and transporting deep into pore spaces during the injection.