Global methane emissions from coal mining to continue ...
May 20, 2020· The gas content of the current global underground hard coal mix 1 thus is in the range between 13 and 18 m 3 /t for mining depths from 450 to 1120 m. For surface mines, the gas content of hard coal is 3–5 m 3 /t for depths from 50 to 200 m and m 3 /t at the constant depth of 50 m for brown coal.. However, the gas content per ton of coal and the emission factor are not equal due to ...