Numerical Simulation of Vertical Well Depressurization with Different Deployments of Radial Laterals in Class 1-Type Hydrate Reservoir

Abstract

Gas production efficiency is a key indicator in the commercial development of natural gas hydrates (NGHs). Based on the data from the first natural gas hydrate field test production in the Shenhu Sea area of China, the gas production capability of Class 1-type hydrate reservoirs was numerically evaluated by vertical well depressurization with different deployment schemes for radial laterals. The results showed that the radial laterals can effectively improve production efficiency and that the radial laterals deployed at the three-phase layer (TPL) have the best production performance. Compared with the single vertical well production, the completion length of the radial laterals is 150 m with a radius of 0.05 m, and the production pressure difference is set to 6 MPa. The cumulative gas production Vg reaches up to 594.10 × 104 ST m3, increased by about 208.53% after 360 days of production, which provides a reference for the development of natural gas hydrates with radial jet drilling (RJD) technology.