Page 246 - Advanced Mine Ventilation

224 Advanced Mine Ventilation

Figure 13.2 Carbon and hydrogen isotopic compositional ranges of methane from different
sources.
Chemical Geology, Ed. M Schoell, Vol 71, 1988, pp. 1-10.

13.5.1 Global Reserve of Coalbed Methane
Coal is found in 70 countries around the world and currently provides 41% of all elec-
tricity consumed [8]. Table 13.8 shows the estimated CBM reserve for selected
countries.
It is a vast reserve of gas that can supplement natural gas reserves globally. Reser-
voir and production engineering for commercial CBM production is available in liter-
ature [8].
Application of horizontal drilling technology with hydrofracturing can easily dou-
ble the US CBM production. For working mines, the benefits of CBM production are
many as listed below:
1. Safety in mines and prevention of disasters.
2. Increased productivity for coal resulting in reduced cost of mining.
3. Additional revenue from gas sales.

13.5.2 The United States Reserves of Coalbed Methane
There are currently 12 coal basins in the United States producing CBM. Detailed de-
scriptions are available in recently published books [5] [8]. Table 13.9 lists the main
basins with their location, CBM production, and reserves.