Due to the limitations in geological conditions and engineering technologies in W oilfield of the Ordos Basin, the development of the tight oil reservoirs in the oilfield generally demonstrates low productivity, poor production stability, insufficient injection, and unsuccessful displacement. It is necessary to modify conventional energy replenishment methods and optimize parameter design for enhanced oil recovery (EOR). In this study, a fracturing-shut-in-production whole-process simulation workflow was developed to reveal the dynamic behaviors of volume fracturing in tight oil reservoirs and analyze the influences of different factors on the performance of energy-replenishing fracturing (ERF). The numerical simulation method was used to optimize the fracturing parameter design. Finally, an innovative ERF technology featured with large fluid volume, high pump rate, low proppant ratio, and shut-in displacement was formed. The research shows that the fracturing fluid volume, matrix permeability, stimulated reservoir volume (SRV) and initial formation pressure are closely related to the effect of shut-in energy storage. The optimal parameters are obtained from the simulation as: the fracture conductivity of 10-15 D·cm, the shut-in time of 30-40 days, the pump rate of 4-6 m3/min, the fracturing fluid volume of 600-800 m3, the proppant volume of 40-55 m3, and the proppant ratio of about 15%. The proposed ERF technology has been successfully applied to tight oil reservoirs, recording an average production rate of 4.33 t/d per well, which is more than four times that (1.08 t/d) of conventional fracturing techniques. This technology addresses the problems of low initial production, rapid production decline and short steady production period in conventional treatments, and provides a reference for stable and efficient development of tight oil reservoirs.
