Review on Hydrate-Based CH4 Separation from Low-Concentration Coalbed Methane in China

The consumption of natural gas is of great importance to optimize China’s energy structure toward reduced CO2 emissions and is projected to increase in the next 10 years. Coalbed methane (CBM) is a primary unconventional natural gas and has been recognized as a significant energy resource to supplement conventional fossil fuels (oil and coal) as a result of its huge potential. It has been established that the hydrate-based gas separation is a promising method for the purification of low-concentration coalbed methane (LCCBM). In this work, the research on hydrate-based CH4 separation from LCCBM conducted by Chinese researchers over the past 10 years has been reviewed. It is found that significant progress has been made to understand the hydrate-based CH4 separation technology. On the other hand, the challenges related to achieving milder pressure operating conditions and enhancing the rate of hydrate formation should be overcome. Hence, further work is required to bridge the gap between the gas separation science and the technology. In this regard, future research directions are proposed in this work to help advance the research of hydrate-based CH4 separation from LCCBM.