What is coal seam gas?
coal bed methane
Coal seam gas (CSG), also known as coal bed methane, is a form of natural gas typically extracted from coal seams at depths of 300-1,000 metres. CSG is a mixture of a number of gases, but is mostly made up of methane (generally 95-97 per cent pure methane).
How does a CSG well work?
To produce coal seam gas (CSG), wells are drilled into underground coal seams, bringing water (CSG water) from the seams to the surface. This process reduces pressure in the seams which allows CSG to be released.
Why is coal seam gas used?
CSG is increasingly being used to supply gas to eastern Australia. CSG, however, is found in coal seams, where underground water pressure keeps it contained. Pumping water out of the coal seam releases this pressure and allows gas to escape from the coal into a well.
How is coal seam gas different?
The difference between conventional and unconventional gas is the geology of the reservoirs from which they are produced and the methods required to extract the gas. CSG is considered unconventional because it requires ‘unconventional’ methods to extract it – such as hydraulic fracturing or horizontal drilling.
Is coal seam gas renewable?
Coal seam gas is a non-renewable energy resource that is a by-product of coal. The methane gas is contained within the coal seams by water from groundwater aquifers.
How do you find a coal seam?
A coal seam is a dark brown or black banded deposit of coal that is visible within layers of rock. These seams are located underground and can be mined using either deep mining or strip mining techniques depending on their proximity to the surface.
How does coal seam gas form?
Gases in coal seams are formed during the long geological process of coal formation (coalification) when organic matter is converted into coal. The gas accumulates underground, held within the cleats (natural fractures) and pores of the coal itself. Not all coal seams contain useful quantities of methane.
Is coal seam gas clean energy?
Coal Seam Gas (CSG) is not a ‘clean transition’ fuel because of the potential for substantial fugitive methane emissions associated with extraction and distribution. CSG may prove to be more damaging to the climate than coal.
Is coal seam gas good or bad?
Some chemicals used in drilling and hydraulic fracturing, and naturally occurring contaminants released from the coal seam during mining, could harm human health, given sufficient dose and duration of exposure. This potential harm includes increased risk of cancer.
What causes a coal seam?
Coal seams originate and are formed by the consolidation of biota, minerals, and natural chemicals through geologic time. Compression, heat, sedimentation, erosion, and chemical energy are agents of the coal formation process.
Is coal seam gas Green?
Vastly different claims are being made about the green credentials of coal seam gas and LNG. Shale gas extraction emits slightly more greenhouse gas than coal seam gas, but their conclusions are still valid.
How is coal seam gas formed?
How is coal seam gas extracted?
Coal seam gas is extracted by drilling a well vertically through rock strata until reaching the coal seam, at which point the well may also be drilled out horizontally to increase access to the methane gas. Coal seams contain both water and gas.
What does coal seam mean?
coal seam (Noun) A stratum of coal between strata of other rocks. How to pronounce coal seam?
Is CBM natural gas?
Coalbed methane (CBM or coal-bed methane), coalbed gas, coal seam gas (CSG), or coal-mine methane (CMM) is a form of natural gas extracted from coal beds. In recent decades it has become an important source of energy in United States, Canada, Australia, and other countries. The term refers to methane adsorbed into the solid matrix of the coal.
How is coal seam degasification?
A coal seam is degasified in advance of its being mined by drilling one or more generally horizontal holes from a working face into the seam, and placing a particulate propping agent into the borehole