On the Development of an Effective Pressure Driving System for Ultra-Low Permeability Reservoirs

Given its relevance to the exploitation of ultra-low permeability reservoirs, which account for a substantial proportion of the world's exploited and still unexploited reserves, in the present study the development of an adequate water injection system is considered. Due to the poor properties and weak seepage capacity of these reservoirs, the water injection pressure typically increases continuously during water flooding. In this research, the impact on such a process of factors as permeability, row spacing, and pressure gradient is evaluated experimentally using a high-pressure large-scale outcrop model. On this basis, a comprehensive evaluation coefficient is introduced able to account for the effective driving pressure.