Coal Mining produces methane gas and if released to atmosphere without treatment, has a major impact on the greenhouse effect and contributes to global warming.
Coal mine gas is released from seams of coal during mining activities and is distinguished between these kinds of coal mine gas as per the below:
Methane exhausted from unexplored coal beds
- Coalbed Methane (CBM)
- Nearly natural gas quality
Methane from active underground mining
- Coal Seam Methane (CSM), sometimes called Coal Mine Methane (CMM)
- Coal Mine Gas out of active coal mining can be lean gas (<40% CH4)
Methane exhausted from abandoned mines
- Abandoned Mine Methane (AMM)
- Hardly combustible due to high CO2/N2-shares
- Methane content diminishes over time and can be below 30%
How to use coal mine gas
Due to the high methane content of 30% to 95%, especially CBM, CMM and AMM are suitable for the utilisation in gas engines. Only lean gas cannot be used for energy generation because of the low methane content of 0.2% to 1.5%.
Benefits of the use of Coal Mine Gas
- Save the environment by capturing and using methane
- Methane is up to 25 times more powerful than CO2 as a greenhouse gas
- Make Money by using Coal Mine Gas through the generation of electricity, heat and cooling
- Generation of CO2-certificates by avoiding methane emissions
- Prevention of pit explosions (at 4-16% CH4 in the air, danger of explosion)
- More comfortable working conditions
- Higher productivity of a coal mine
MWM gas engines in CHP plants using coal mine gas convert up to 90 % of the energy bound in methane into heat and power.