• How is methane extracted?

Since CBM travels with ground water in coal seams, extraction of CBM involves pumping available water from the seam in order to reduce the water pressure that holds gas in the seam. CBM has very low solubility in water and readily separates as pressure decreases, allowing it to be piped out of the well separately from the water. Water moving from the coal seam to the well bore encourages gas migration toward the well.

• What is the current status of coal-bed methane exploration in India?

The coal-bearing formations of India occur in two distinct geological horizons in the lower Gondwana (Permian) belts of India and the tertiary sediments (Eocene-Oliocene) of north-eastern India, Rajasthan, Gujarat, and Jammu and Kashmir. Methane gas is entrapped within these formations at a wide range of sub-surface depths. CBM possibilities exist mainly in coalfields of the eastern region though there are promising mines in the Godavari basin and Barner basin (lignite) in the West. India formulated its CBM policy in 1997 and according to a memorandum of understanding between the coal ministry and the ministry of petroleum and natural gas, llotment of CBM blocks was started. So far three rounds of bidding have taken place, with the petroleum ministry inviting offers for 10 CBM blocks in the third round on February 27, 2006, the contracts for which have just been awarded.

• Besides being an energy source, are there other positives to India of CBM?

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