Research on technical policy limits of inter-layer injection-production coupling development in low-permeability reservoirs

Abstract

In the conventional development of low-permeability heterogeneous reservoirs, there are issues such as significant inter-layer interference, poor utilization of low-permeability layer reserves, and low recovery efficiency. To address these issues, the heterogeneity theoretical model is built according to the reservoir parameters of the H34 fault-block. The technical policy limits of inter-layer injection-production coupling development are studied using a numerical simulation method. By comparing the development performance of inter-layer injection-production coupling and conventional production, the impact laws of key parameters such as permeability contrast, crude oil viscosity, and cyclic coupling period on development performance are clarified. The study shows that inter-layer injection-production coupling development can effectively eliminate inter-layer interference, enhance the utilization degree of low permeability layers, and raise the overall recovery efficiency by 4.68 percentage points and the recovery efficiency of low permeability layers by 9.18 percentage points. When the permeability contrast is greater than 3, and the crude oil viscosity is lower than 50 mPa.s, the effect of inter-layer injection-production coupling development is significantly enhanced. The optimal cyclic coupling period ranges from 1 to 3 months. This study forms the applicable conditions and parameter optimization limits of inter-layer injection-production coupling for low-permeability reservoirs, providing theoretical support for the efficient adjustment of similar reservoirs.