Methane, CH4, is a naturally occurring gas; it is the major component (95 percent) of natural gas. It can be produced in a variety of ways. For example, methane is produced during the natural coalification process, when organic matter such as trees or vegetation is quickly buried and then heated. Methane can also be produced by farming and ranching activities or as a byproduct of industrial processes. Methane is a greenhouse gas that remains in the atmosphere for up to 15 years, and it is also a relatively inexpensive, clean burning fuel.
Coalbed methane is natural gas that is produced as organic material and turned into coal. It is then stored on the many surfaces of the coal. The methane is usually held in place by water pressure.
Coalbed methane is associated with coal deposits, and is found in coal seams. In the past, the gas was the cause of numerous explosions in underground mines. More recently, the gas has been vented to the surface from underground mines. It is only during the last twenty-five years that it was realized that coalbed methane could be used as a resource. Various basins in the Rocky Mountains, such as the Powder River Basin, partly on the Crow Reservation, hold much of this country's coalbed methane resources.
When water is removed from a coal seam, it lowers the reservoir pressure. Methane that was held in place by water pressure tends to follow the water as it is pumped to the surface, where it is captured and transported through pipelines to storage facilities or shipped. This relatively inexpensive and straightforward procedure has made coalbed methane a useful, easily accessible form of energy.
To further investigate methane gas, follow the links below.
Resources containing information on methane gas.
To further investigate coalbed methane, follow the links below.
Resources containing information on coalbed methane.