Comprehensive evaluation of waterflooding front in low-permeability reservoir

Abstract

Due to the development characteristics of low-permeability reservoirs such as weak water absorption, slow development of water injection, and strong pressure sensitivity, the effect of water injection in low-permeability reservoirs is quite different from that in medium and high-permeability reservoirs. Therefore, in oilfield development, it is important to study the movement law of the waterflooding front in low-permeability reservoirs. In this paper, taking the Jilin oilfield as an example, a geological model of Xinmin 23 Block was established for the numerical simulation analysis considering the heterogeneity of low-permeability reservoirs. In addition, artificial cores were manufactured to conduct the physical experiment of the waterflood front advance of cores with different physical properties under the influence of various factors such as the fracture and the range by the constant-velocity flooding. Based on the numerical simulation and the physical experiment, the movement law of the waterflood front was analyzed and a basic method for evaluating the waterflooding development in low-permeability reservoirs was established to provide feasible insights for the waterflooding development in low-permeability reservoirs. In this paper, numerical simulation and experimental studies were performed on the effect of the waterflooding development of Xinmin 23 Block in the Jilin oilfield. The evaluation results obtained were consistent with the actual oil production providing a theoretical basis for judging the accurate advance time from the waterflood front to the production well in actual oil production.