Coal Washing

This article is a stub. Please help Climate Lab by expanding it. (April 2010)

Coal Washing is part of a broad group of technologies that aim to reduce the adverse environmental impacts of generating energy from coal. The technique involves washing the coal to remove it of its impurities before it is burned for energy combustion.

Coal is first ground into smaller pieces so that it can be more easily processed. The pulverized coal is then washed in water or in fluids with densities that cause the coal to float so that unwanted impurities can sink to the bottom¹. Coal Washing reduces the ash content of coal by over 50%, resulting in less waste². About 25% of the sulfur content is reduced, lowering the amount of sulfur dioxide emissions released upon combustion. Coal washing also improves the heating value of coal, known as the thermal efficiency, which reduces carbon dioxide emissions as well³.

While coal washing effectively removes some impurities from coal and reduces emissions, it does not result in a completely clean technology. The generation and disposal of waste produced by this process is still an issue yet to be resolved⁴.