Abstract:
The clean and green transition of the coal industry is an essential requirement for achieving high-quality development, and a critical lever for implementing the “dual carbon” goals. As the most energy intensive and emission heavy phase in coal production, quantifying emission reduction effectiveness in coal extraction is vital for advancing sector-wide carbon neutrality. Therefore, the carbon emission sources of underground coal mining and open-pit coal mining are analyzed and identified respectively, develops two carbon footprint models, evaluates their carbon footprint outcomes and sensitivity, and proposes carbon neutrality pathways. The conclusions are as follows: The carbon footprint of 1 ton of lignite underground mining is 408 kgCO
2e/t, and that of open-pit mining is 79.7 kgCO
2e/t. Methane emissions contributed dominantly to the carbon footprint, accounting for 90.13% (underground) and 58.80% (open-pit). In underground coal mining, electricity and methane were identified as key inventory items, with comprehensive sensitivity indices of 62.35% and 10.01%, respectively. For surface coal mining, emulsified explosives exhibited a moderately high environmental sensitivity, reaching a comprehensive sensitivity of 63.25%. Based on error propagation for quantifying the uncertainty of individual environmental indicators, the resulting uncertainty in the carbon footprint for underground coal mining was ±28.93%, and for surface mining, it was ±20.18%. Based on carbon footprint calculation and sensitivity analysis, underground mine should implement real-time methane monitoring, gas drainage systems, and full-concentration methane utilization technologies. In open-pit mining areas, biomass-based emulsion explosives are adopted to replace traditional diesel formulas, enhancing blasting efficiency and reducing the generation of acidified pollutants. Meanwhile, methane purification processes are coupled with renewable energy systems to establish a methane emission control system oriented towards the "dual carbon" goals.