A three-dimensional study on methane hydrate decomposition with different methods using five-spot well

The cubic hydrate simulator (CHS) is used to study the methane hydrate production behaviors in porous media with three different methods, which are the depressurization (DP) using a single well, the heat stimulation using five-spot well (HS-5S), and the heat stimulation in conjunction with depressurization using five-spot well (H&D-5S), respectively. During these experiments, the initial hydrate saturations are all 35%; environmental temperatures are all 281.15 K; and the production pressures are ranged from 4.7 MPa to 7.4 MPa. The injection temperature (Tinj) and the rate of hot water injection (Rinj) in the experiments with the HS-5S and H&D-5S methods are 10 ml/min and 160 °C, respectively. The analysis of hydrate decomposition shows that almost all of the hydrate can be decomposed in the hydrate reservoirs with the above methods. The H&D-5S method, which can obtain the largest volume of gas production, the highest gas production rate, and the shortest production time, is the optimal method for hydrate production in this work.