Microwave-assisted high-efficient gas production of depressurization-induced methane hydrate exploitation

• Published in: Energy
• Main Authors: Wang, Bin, Liu, Shuyang, Wang, Pengfei
• Format: Report
• Language: English
• Published: PERGAMON-ELSEVIER SCIENCE LTD 2022
• Subjects: Natural gas hydrate; Microwave heating; Depressurization; Energy efficiency; Operational strategy optimization; THERMAL-STIMULATION; ENERGY RECOVERY; DISSOCIATION; RESERVOIR; SEDIMENT; PERMEABILITY; SIMULATION; CONSTANT; WELLBORE; Thermodynamics; Energy & Fuels; Methane hydrate
• Online Access: http://ir.giec.ac.cn/handle/344007/36497; http://ir.giec.ac.cn/handle/344007/36498; https://doi.org/10.1016/j.energy.2022.123353

To provide solution for the high-efficient gas production from hydrate deposits, the microwave-assisted depressurization method is proposed, and its feasibility is numerically demonstrated. Through systematically analyzing the effects of microwave parameters, phase components, and porous media properties, we found that microwave heating can provide timely and sufficient energy for hydrate dissociation, and the energy efficiency of microwave heating can be relatively high in the condition of high initial water saturation, high initial hydrate saturation, low specific heat capacity, high thermal conductivity, high porosity, and low absolute permeability. In addition, the microwave heating operational strategy is evaluated and optimized to achieve the high energy efficiency and rapid gas production, which demonstrating that the one-cycle continuous heating mode has the best performance on promoting hydrate dissociation. Compared to the typical heating case, the energy efficiency and gas generation efficiency in the optimized one-cycle continuous heating case are enhanced by 20.73% and 23.14%, respectively. The findings of this study contribute to the understanding of gas production behavior of depressurization induced hydrate dissociation assisted by microwave heating, which can provide some insights for evaluating and optimizing the methodology for gas production from gas hydrate reservoirs.(c) 2022 Elsevier Ltd. All rights reserved.