Thoughts on the development path of coal and gas co-mining technology in dual carbon strategy

Abstract

The construction of China’s ecological civilization has entered a critical period in which carbon reduction is the key strategic direction since the “dual carbon” goal was proposed. Coal’s status as the least expensive energy source will be unchanged in the short term. CH4-CO2 coordinated emission reduction is the core of the convert from “dual control” of energy consumption to “dual control” of total carbon emissions and intensity. On the basis of accurately analyzing the challenges of CH4-CO2 dual carbon emission reduction in coal mines at the stage of carbon peak and carbon neutrality, the development of coal and gas co-mining technology in the dual carbon strategy has been clarified to be combined with the core principles of current demand-technical research-policy drive, the development path of coal and gas co-mining technology in the dual carbon strategy is formulated, and the key technical issues are discussed. At the peak stage of carbon emission, CH4 emission reduction is based on the perspective of emission source control. The core is the key technology for carbon emission reduction in the whole cycle of gas extraction and utilization, including the targeted and accurate extraction technology in gas-rich areas, the permeability-enhancement, replacement and flow-increasement extraction by injecting gas in low-permeability coal seams, the gas escape channel plugging and carbon reduction technology in closed mines, and the integrated technology of gas enrichment-concentration-utilization. The purpose is to greatly improve the efficiency of high-concentration gas extraction and utilization and to reduce the carbon emission from low-concentration and ventilated gas. CO2 emission reduction is centered on the “CCUS + ecological carbon sink” region-wide negative carbon emission technology to further absorb flue gas and pure CO2 emissions, including CO2 storage in coal seams, industrial solid waste goaf filling synergistic CO2 geological storage, soil-surface-atmosphere anomaly monitoring and ecological carbon sink technology in coal mine carbon storage areas, etc. The core task of the carbon neutralization stage is to achieve CH4-CO2 (near) zero carbon emission. CO2 emission reduction should be transformed from a technical research demonstration project to a large-scale application stage, and establishing an intelligent monitoring and dynamic control technology system for CH4-CO2 emission from coal mine in the whole life cycle to realize the in-deep matching between monitoring and control technology means and carbon emission links, and the in-deep docking between the monitoring-control cloud platform of carbon emission and the global monitoring-control system of coal mines. Finally, the insights and thoughts is put forward on the green and low-carbon development of the future coal and gas co-mining system. ① Continue to deepen the coal mine CH4 zero emission technology model of “efficient and accurate extraction + full-concentration cascade utilization”. ② Continue to tackle the CO2 zero emission technology system of “CO2 engineering storage + ecological carbon sinks”. ③ Actively exploring the comprehensive solution of “zero carbon wisdom park” in coal mines, and forming a policy support system for carbon emission reduction in coal mines that emphasizes both incentive and pushback.

Keywords

• dual carbon goal
• ch4−co2 synergistic emission reduction
• gas co-extraction
• development path
• green and low-carbon technology