Bottom-Up Estimates of Coal Mine Methane Emissions in China: A Gridded Inventory, Emission Factors, and Trends

Emissions from fossil fuels are one of the primary sources of atmospheric methane (CH4) growth. However, estimates of anthropogenic CH4 emissions still show large uncertainties on global and regional scales. Differences in CH4 isotopic source signatures &#948;13C and &#948;D can help to constrain different source contributions (e.g. fossil, thermogenic, or biogenic).The Upper Silesian Coal Basin (USCB) represents one of the largest European CH4 emission source regions, with more than 500 Gg CH4 yr-1 released by more than 50 coal mine ventilation shafts. During the CoMet (Carbon Dioxide and Methane Mission) campaign in June 2018 methane observations were conducted from a variety of platforms including aircraft and cars. Beside the continuous sampling of atmospheric methane concentration, numerous air samples were taken from inside the ventilation shafts, around the ventilation shafts (1&#8209;2&#160;km distance) and aboard the DLR Cessna Caravan aircraft and analyzed in the laboratory for the isotopic composition of CH4.The ground-based samples allowed determining the source signatures of individual ventilation shafts. These signatures displayed a considerable range between different shafts and also varied from day to day. The airborne samples contained a mixture of methane emissions from several mines and thus enabled accurately determining the signature of the entire region. The mean isotopic signature of methane emissions over the USCB derived from the aircraft samples was -51.9&#160;&#177;&#160;0.5&#160;&#8240; for &#948;13C and -233&#160;&#177; 6&#160;&#8240; for &#948;D. This is in between the range of other microbial and thermogenic coal reservoirs, but more depleted in &#948;D than previous USCB studies reported based on samples taken within the mines. Signatures of methane enhancements sampled upwind of the mines and in the free troposphere clearly showed the presence of methane of biogenic origin (e.g. wetlands, waste, ruminants).Furthermore, we simulated the methane isotopologues using the on-line three-times nested global regional chemistry climate model MECO(n). We implemented a submodel extension, which includes the kinetic fractionation and uses the isotopic source signatures determined by the ground-based observations. We compare the regional simulations to flask samples taken during CoMet.

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Quantifying Methane Emissions from Super-emitter Coal Mines using TROPOMI Observations

10.5194/egusphere-egu21-15693 ◽

2021 ◽

Author(s):

Pankaj Sadavarte ◽

Sudhanshu Pandey ◽

Joannes D. Maasakkers ◽

Alba Lorente ◽

Tobias Borsdorff ◽

...

Keyword(s):

Greenhouse Gas ◽

Coal Mine ◽

Greenhouse Gas Emission ◽

Coal Mines ◽

Oil And Gas Industry ◽

Methane Emissions ◽

Point Sources ◽

Satellite Observations ◽

Intergovernmental Panel ◽

Bottom Up

In the context of the Paris Agreement goal of limiting global warming to below 2 degrees Celsius, the Representative Concentration Pathways (RCP) 2.6 of the Intergovernmental Panel on Climate Change (IPCC) have framed greenhouse gas emission scenarios emphasizing a sharp reduction in methane (CH4) emissions with the current increasing trend. Recent studies have shown that satellite observations of atmospheric methane can be used to detect and quantify localized methane sources on a facility-level for the oil and gas industry. We use satellite observations from TROPOMI to understand the high and persistent methane signals from ventilation shafts in the coal mining industry. &#160;Even the bottom-up and top-down global estimates infer coal mine methane responsible for ~12% of the anthropogenic methane emissions. TROPOMI onboard Sentinel-5P has a ground pixel resolution of 5 &#215; 7 km2 at nadir, which allows detection of large local to point sources. With its daily global coverage, we identify high methane emission sources over coal mine regions in Australia during 2018 and 2019 and quantify methane emissions using the fast data-driven cross-sectional flux method. Our initial results show that TROPOMI estimates are higher than bottom-up global emission inventories. We will present emission estimates using satellite-based quantification for super-emitter coal mines and evaluate its implication on national greenhouse gas reporting.

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Study on the Interprovincial Emission Factor of Chinese Coal Mine Methane

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.295-298.3354 ◽

2013 ◽

Vol 295-298 ◽

pp. 3354-3358

Author(s):

Ning Wang ◽

Tao Zhu ◽

Sha Chen ◽

Da Wei Luo

Keyword(s):

Coal Mine ◽

Emission Factor ◽

Discharge Coefficient ◽

Regression Function ◽

Emission Factors ◽

Coal Production ◽

Function Model ◽

Coal Mine Methane ◽

Different Types ◽

Chinese Coal

From the basic conditions of Chinese Coal Mine Methane (CMM) emission, the thesis studies the CMM discharge coefficient of different types of mines in china after establishing the “the output - emission regression function model” by the means of raw coal production. Besides, according to CMM’ distribution in different provinces’ (areas) of China, interprovincial emission factors will be calculated, laying foundation for the calculation of the CMM’s emission and reduction.

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