CSG

 

Tri-Star is the pioneer of the CSG industry in Queensland. The tenures which Tri-Star discovered and developed at Durham Ranch, Spring Gully and Fairview are not only the best in Australia, but some are the best in the world. Well productivity, production life and proximity to major infrastructure and ports compare favourably with other CSG fields in Australia and elsewhere. Tri-Star flared the first CSG well in 1994 and the first LNG project is planned for export in 2015.

 

CSG

What is CSG?

Coal seam gas (CSG) is a natural form of gas that is trapped in coal seams. It is also known as Coal Seam Methane.  While it is classified as “unconventional" due to its source in coal, it is similar to conventional natural gas.  CSG is produced during the geological formation of coal from peat (decaying vegetable matter). The methane in CSG is absorbed (attached) onto the surface of the coal under pressure. As coal can only hold approximately 10 per cent of the methane it produces, it gradually expels the gas from the seam over time.

Methane, the primary constituent of both conventional natural gas and CSG, is one of the cleanest burning fossil fuels. Demand for CSG is rising as nuclear plants are decommissioned across Asia and Europe. These environmental factors, combined with the advent of LNG technology, have propelled gas to the forefront of energy policies as an important source of fuel.

 

Coal

How is CSG extracted?

To obtain the methane from the coal, water is pumped from a well, reducing pressure and causing the methane to release (desorb) and begin to flow from the coal. The coal’s permeability allows the gas to flow through the coal to the producing well.

The gas flow increases as water pressure decreases. After a number of months, gas flow can be sufficiently high that pumping of water ceases and the gas will continue to flow.

Each gas well is connected via underground gas and water pipelines.  As gas flows from the wells it is transferred via pipeline to centralised compressor facilities for processing. The gas is then distributed to commercial markets via underground high-pressure transmission pipelines. At this stage, the gas can be transferred to a Liquefied Natural Gas (LNG) plant, where it is cooled and converted to a liquid for transport. Any excess water is transferred to treatment points.

Tri-Star recognises the importance of strategic and proactive management of CSG water by CSG operators to reduce environmental impact and provide benefit to the community wherever possible.

 


For further information on the CSG
to LNG industry in Queensland
click here.


For an overview of Queensland's coal seam gas industry click here.