Generation and Extraction of CMM in general
CMM is generated during extration of coal. The methane is a product from the coalification of the biological material started 300 million years ago. A part of this methane is still connected to the coal layers and the surrounding. This methane is a risk for mining, because of possible explosive gas-air-mitures. For safe mining it is necessary to capture the methane.
Extraction methods
Active Mines
Extraction methods
- pre degassing
- Boreholes underground
- Boreholes from surface
The pictures above show different kind of boreholes for extraction of CMM. The type of gas extraction vary depending on the coalfield and geological conditions.
Abandonend Mines
Possibilities for the CMM-extraction of abandoned coal mines
- Using of historcal boreholes
- Drilling of new borehols
- Use of existing infrastructure
