Study on the change of reservoir seepage flow by microbial oil drive in the reservoir after polydynamic drive

Abstract

Microbial drive is an effective technical means to enhance low-permeability reservoirs. There is a large amount of residual oil in the reservoir after polydrive, so there is an urgent need to explore effective ways to improve the recovery rate. Combining the actual needs of the XK well area and the characteristics of microbial oil recovery technology, we carried out the numerical simulation study of microbial drive and evaluated the changes in seepage capacity of the reservoir and typical wells at different stages. The results show that in the first cycle of microbial injection, the seepage capacity around the injection wells is obviously improved, but the seepage capacity of each reservoir in the second cycle is not improved as well as that in the first cycle; the improvement of seepage capacity around the injection wells is related to the permeability of the reservoirs and the effective thickness; the higher the permeability and the thicker the effective thickness are, the faster the seepage capacity of the near-well zones is improved, and the bigger the improvement amplitude is, and the earlier the production wells nearby are able to see the effect. This study provides guidance for field tests and is of great significance for the improvement of reservoir recovery after polydynamic drive.