Simulation study of water shut-off treatment for heterogeneous layered oil reservoirs

Abstract

The purpose of this paper is to develop a hydrodynamic model of two-phase, three-component fluid flow in a heterogeneous layered reservoir, taking into account cross-flow between layers, and to predict the process of oil displacement by water under conditions of water shut-off in the vicinity of injection or production wells. Numerical calculations at different water cuts (38%, 50%, 96%) showed that in the presence of cross-flow between layers, the current oil recovery coefficient of the reservoir at water shut-off in the vicinity of the producing well increases by 0.3254, 0.3067, and 0.0429 respectively, compared to water shut-off in the vicinity of the injection well. In the absence of cross-flow between layers, there is a decrease in oil recovery coefficient by 0.0082 and 0.0072 at 38 and 50% water cut, respectively. Additionally, there is an increase in recovery coefficient by 0.007 at 96% water cut. It was also obtained that in the presence of cross-flow between layers the gel washout period at water shut-off in the vicinity of the injection well is less at different water cut in 1.24–1.81 times than in the vicinity of the production well. In the absence of cross-flow between layers, the washout time at 38 and 50% water cut is almost the same, but increases by 1.084 times at 96% water cut. Comparison of results of water shut-off prediction using proposed hydrodynamic model and real data showed that calculations describe real data with an average error of about 7%.