ash content

Ash content in coal refers to the mineral matter present in it. When coal is burned, these minerals transform into ash. The quantity and behavior of this ash at high temperatures are important factors in designing and operating coal-utilization plants, influencing the type of ash-handling systems needed. Ash can become sticky and form molten slag at high temperatures, which then solidifies into a hard material upon cooling. Laboratory tests determine ash-fusion temperatures to predict how coals will behave during high-temperature processing, specifically their clinkering potential. While ash does not contribute to coal's heating value and can be a source of pollution, in some cases, its presence, along with mineral matter, can be desirable for specific applications like chemical sourcing or coal liquefaction.12