Evaluation of the Gas Production Enhancement Effect of Boundary Sealing and Wellbore Heating for Class 1 Hydrate Reservoir Depressurization with a Novel Five-Spot Radial Wells System

Commercialization of natural gas hydrates still faces challenges. Before large-scale production becomes feasible, efficient exploitation methods must be continuously explored. Based on field data from China’s first trial production, a novel five-spot radial wells system design, combined with boundary sealing and wellbore heating, is proposed to improve production capacity. Simulation results indicate that boundary sealing can inhibit water invasion and concentrate energy, thereby promoting hydrate dissociation. The radial laterals significantly expand the drainage area and increase pressure propagation. Wellbore heating can accelerate the dissociation of hydrates while inhibiting secondary hydrate generation. The combined application of these technologies has significantly increased the cumulative gas production and gas-to-water ratio to 244.9% and 134.6% of the base case, respectively, providing theoretical references for the effective exploitation of Class 1 hydrate reservoirs.