Numerical Investigation on Hot Water Injection Process Along Fractures of Methane Hydrate Reservoirs

Natural gas hydrate (NGH) is considered one of the most promising alternative energy resources because of its high-energy density, abundance in nature and cleanness. The key challenge for commercial exploitation and utilization of this energy resource is how to increase the permeability of NGH reservoirs which benefits gas production efficiency. This study proposes a method for increasing NGH reservoir permeability by the combination of applying hydraulic fracturing method to induce artificial fractures in NGH reservoirs and then injecting hot water into the fractures, and conducts a numerical investigation on the hot water injection process. The results indicate that hot water can flow into the deep region of NGH reservoir, along which a high-temperature and high-permeability zone forms, and the higher the injection rate, the larger this zone.