Analysis of the Characteristics of CH Emissions in China's Coal Mining Industry and Research on Emission Reduction Measures.

CH is the second-largest greenhouse gas and has a significant impact on global warming. China has the largest amount of anthropogenic coal mine methane (CMM) emissions in the world, with coal mining emissions (or gas emissions) accounting for 90% of total energy industry emissions. The results of CH emission inventories from previous studies vary widely, with differences in the spatial and temporal dimensions of gas emission factors of belowground mining being the main points of disagreement. Affected by the policies of "eliminating backward production capacity" and "transferring energy base to the northwest", China's coal production layout has changed greatly in the past ten years, but the closely related CH emission factors have not been dynamically adjusted. This paper investigated 23 major coal producing provinces in China, obtained CH emission data from coal mining, calculated CH emission factors in line with current production conditions, and studied the reduction measures of coal mine gas emission. According to the CH emission data of China's coal mines in 2018, 15.8 Tg of methane is released per year in the coal mining industry in China, and 11.8 Tg after deducting recycling. Shanxi Province's CH emissions are much higher than those of other provinces, accounting for 35.5% of the country's total emissions. The weighted CH emission factor of coal mining in China is 6.77 m/t, of which Chongqing is the highest at approximately 60.9 m/t. Compared with the predicted value of the IPCC, the growth trend of CCM has slowed significantly, and the CH utilization rate has gradually increased. This change may be aided by China's coal industry's policy to resolve excess capacity by closing many high-gas and gas outburst coal mines. In addition, the improvement of coal mine gas extraction and utilization technology has also produced a relatively significant effect. This paper determines the distribution of methane emissions and emission sources in China's coal mining industry, which is useful in formulating CCM emission reduction targets and adopting more efficient measures.