Study on Parameters Optimization and Adaptation of Nitrogen Foam Flooding in Reservoirs with High Water Cut and High Permeability

Abstract

Most oil reservoirs in China have entered the stage of high water cut. Affected by the heterogeneity of the reservoir, the water flow dominance channel is easily formed between injection-production wells in the plane direction of such reservoirs, and the phenomenon of water channelling is intensified. Therefore, a numerical simulation study of nitrogen foam flooding is carried out in this paper. According to the reservoir characteristics of the target block, the adaptability of nitrogen foam flooding to reservoirs in the ultra-high water cut stage is studied, the parameters of injection and production are optimized, and the applicable limits of nitrogen foam and the sensitivity of reservoir parameters are analysed. The optimization results of foam flooding indexes obtained through numerical simulation are as follows: the injection method of nitrogen foam is a mixed injection, the injection volume is 0.3 PV, the injection rate is 200 m3/d, the concentration of foaming agent is 0.5 wt%, and the gas–liquid ratio is 1: 1. The results show that for high-water-cut reservoirs, nitrogen foam flooding technology can effectively improve the water flooding effect of reservoirs and enhance oil recovery. It exhibits excellent adaptability to such reservoirs and has a very board application prospect. The results of numerical simulation optimization can provide theoretical guidance for field applications.