Technoeconomic analysis on nitrogen reverse Brayton cycles for ...
1. Introduction. Coalbed methane (CBM) is an unconventional natural gas (NG) stored in coal seams. China has relatively rich CBM reserves, ranking after Russia and Canada [1, 2].By the end of 2019, the technicallyrecoverable CBM reserves remain at about billion cubic meters [3].Most CBM is emitted from the coal mining process, and they are generally blended with lots of air, which ...