The objective of this study is the analysis of gas production scenarios from gas-hydrate-bearing zone. The zone is characterized by a 15-m-thick hydrate accumulation, the base of which marks the bottom of the hydrate stability zone. The temperature at the bottom of the hydrate layer is 13.5°C, the gas hydrate equilibrium temperature at the formation pressure of 10.7 MPa. The gas hydrate interval has a hydrate saturation SH=0.7, the rest being gas. The analysis of the production scenarios in this paper were conducted using the TOUGH+HYDRATE general-purpose simulator for multi-component, multiphase fluid and heat flow and transport in the subsurface with the EOSHYDR HYDRATE module. Using numerical simulation, we estimate the rates of gas production and gas release from hydrate dissociation, the corresponding cumulative volumes of released and produced gas in single hydrate exploitation well that production gas using depressurize technology. The results of this study indicate that, the decomposition speed of gas hydrate is from high to small, and the process is cycle. The general trend of gas volume production from hydrate is increasing. So as to keep the gas volume stable of gas production from gas hydrate, a certain degree of heat should be added to the gas hydrate production well cyclically in accordance with design parameters. The results of study provide a theory and technical foundation for natural gas hydrate mining able and economic evaluation.

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