Coal Seam Gas
What Is Coal Seam Gas?
forms over millions of years, storing large quantities of a methane-rich gas and coal seam gas (CSG). Other names for gas extracted from underground coal deposits are:
- Coal bed methane (CBM)
- Coalbed methane
- “Unconventional gas”
- “Sweet gas”
Unlike coal, the coal seam gas lacks hydrogen sulphide. The methane lines the inside pores of the coal and is also found in the cleats (open fractures in the coal) and seams. The gas is held in place by water pressure.
The gas is extracted by drilling a steel-encased hole into the coal seam. Natural gas is released from the coal as the water is pumped out. The water is removed from the gas allowing the gas to be piped to a compressor station for injection into natural gas pipelines. The water is either sent to evaporation ponds, released into streams, re-injected into isolated formations or used for irrigation.
Check out a great video from QGC
, an Australian coal seam gas explorer and producer, explaining the coal seam gas process using an animation.
What Is Coal Seam Gas Used For?
Coal seam gas has become a very important source of energy, especially within Australia where it supplies over 60% of the total gas market in Queensland. Gas is used to supply some of our electricity needs like running our lights, appliances and hot water. The About Gas
“During peak times of electricity demand, such as mass high usage of heaters and air-conditioners, power stations can rely on a gas supply to help generate more power. Many products we use at home or work are manufactured using gas as an energy source, including glass, fabrics, steel, paint, plastics and agricultural fertilizers. More cars are running on gas and increased numbers of buses use gas as an efficient fuel alternative.”
Where Is Coal Seam Gas Produced?
There are large reserves of coal bed methane in Canada and the United States but Australia is the main producer of coal seam gas with 18 mining operations currently being used.
Coal seam gas is a newer energy resource being largely explored in Queensland, Australia. Coal is a source and reservoir for methane gas. This gas is sealed inside the coal by water pressure and is only released once drilling into the coal occurs. The gas is extracted by pumping up the water from the coal seam releasing the gas. The gas is sent through a gas pipeline to be used as a power generator in both industrial and home settings.
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