Applicability analysis for single horizontal well SAGD in heavy oil reservoir and optimization of injection-production scheme

Key words:  single horizontal well  steam assisted gravity drainage  reservoir screening  viscosity of crude oil  injection-production parameters

Abstract:

The single horizontal well steam assisted gravity drainage(SAGD) technology can effectively improve the development effect of thin heavy oil reservoirs. The adaptability analysis of the single horizontal well SAGD development technology was carried out by the numerical simulation method. Based on the economic limit index of reservoir development, the principles of reservoir adaptive screening were formed, and the optimization of injection-production scheme was carried out with the goal of highest oil-steam ratio. The results indicate that the thicker the reservoir, the greater the porosity, permeability and oil saturation, the more conducive to the single horizontal well SAGD development. Its development effect decreases with the increase of the viscosity of the reservoir crude oil. According to the classification for the viscosity of the crude oil, the thin reservoir suitable for a single horizontal well SAGD exploitation is screened. The single horizontal well SAGD development effect is the best with the value decreasing of 60 m³/d and value stabilizing of 200 m³/d for the steam injection rate, the production-injection ratio being in the range of 1.15-1.20, the horizontal well perforation section length being 120 m, and the horizontal well inclination angle being 1.32°.