Clean coal refers to coal that underwent any clean coal technology (CCT) process. The Australian Coal Association describes clean coal technologies as technologies that are designed to enhance both the efficiency and the environmental acceptability of coal extraction, preparation, and use. It is meant to reduce emissions and wastes as well as increase the amount of energy gained from each ton of coal. Currently, there are a lot of CCTs in use and in development but their economic viability still remains to be seen.
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