Physical Simulation Study on Horizontal Well Injection and Production in Ultra-low Permeability Reservoirs

In order to study the displacement mechanism between horizontal well fractures, seepage law, and the impact of horizontal well renovation parameters on development effectiveness, a large-scale outcrop rock sample physical simulation test was established. Based on the actual conditions of the oil reservoir, model parameters were designed to study the percolation mechanism of inter fracture displacement, the influence of fracture parameters and injection parameters on development effectiveness, and the influence of three displacement media tests: inter fracture water drive, natural gas drive, and surfactant drive on development effectiveness. This experiment revealed the displacement mechanism, seepage law, pressure change process, and production performance characteristics between horizontal wells in ultra-low permeability reservoirs. The experimental results indicate that: ① Physical model tests can effectively simulate the seepage law during the injection and production process of horizontal wells in ultra-low permeability reservoirs. ② Horizontal well fracture displacement is more likely to form linear displacement and improve oil recovery efficiency of the reservoir The horizontal well injection line has a well spacing of 200 m, a crack spacing of 156 m, and a half crack length of 178 m, resulting in the highest recovery rate. ④ The injection pressure is limited to the rupture pressure, and the higher the displacement pressure, the higher the recovery degree. ⑤ The final recovery rate of water flooding between fractures is the highest, and the recovery rate of natural gas and surfactant flooding between fractures is lower than that of water flooding between fractures.