“Brown” coal – or lignite – is a carbon fuel that is softer, wetter and less energy efficient than bituminous, or “black” coal.
Australia has extensive brown coal reserves, particularly in Victoria’s Latrobe region, making it a valuable domestic energy resource and export product.
The low heating power of brown coal, combined with its high availability, has traditionally meant energy producers simply burn large amounts of the resource to generate the required energy.
But brown coal's high moisture content means it is a particularly smoky fuel to burn, and brown coal-fired stations are considered some of the most polluting power generators in the world.
According to Victorian Energy Minister Theo Theophanous, more than 90% of the state’s power is derived from its brown coal resources at various power plants, including Hazelwood, once rated the highest polluting power plant in the world.
New technology developed through the Cooperative Research Centre for Clean Power from Lignite will be put into action with the construction of a $A6.3 million pilot plant at the Loy Yang Power site in the Latrobe Valley, adjacent to the Loy Yang Coal mine site.
The pilot plant will use a process called mechanical thermal extraction, designed to heat and squeeze brown coal, thus reducing the energy required to evaporate its high moisture content.
The CRC said MTE technology also makes it possible to capture concentrated amounts of carbon dioxide from the waste stream for burial or sequestration at a later stage.
The Victorian and Federal governments have each provided $A2.2 million for the project, with the remaining $A1.9 million provided by power suppliers in the region seeking to lower the environmental impact of their operations.
The MTE plant is expected to be able to process up to 15 tonnes of brown coal per hour.
If the pilot plant proves successful, stakeholders hope to retrofit the technology to existing power plants in the region and integrate it into future brown coal-fired power plants.
The construction of the pilot plant is scheduled to commence in May 2006 and the overall project will conclude in mid 2007.
