Underground CMM extracting system

Underground CMM extracting systems are installed in digging areas where the gas release during mining is so enormus, that the Methane content in the ventilation air can reach more than 1%.

Under current coal mine regulations in many countries, methane must be controlled at the working faces and at other points in the mine. A well-designed ventilation system performed it long time. Because of higher productivity and higher methane content towards deeper coal seams this task became more difficult in modern coal mines. So a CMM extracting system was developed during the depending on the local conditions. One of these methodes is an underground pipeline grid to suck the gas to the surface by a centtral degassing station.

Scheme of degassing

The gas is extracted from the surrounding area of the coal layer. The boreholes are connected to the degassing pipe. This pipe leads the gas through a shaft to the zentral degassing station on the surface. For more information visit * http://www.epa.gov/cmop/resources/drain_degas.html

Gas which is released and not collected by the borehole of the extracting system flows into the ventilation air. The methane is transported to the ventilation shaft. The concentration of methane has to be less than 1 % in every place. Mostly higher concentration mus have a special permission by the coal authority.