bottom ash

waste disposal

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June 22, 2026

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Bottom ash is the inert residue left after the incineration of municipal solid waste. It is composed of ash, glass, metal, and other solid materials. This material, along with fly ash (cinders, dust, and soot), is typically combined and disposed of in a landfill. If the ash contains toxic metals, it is managed as hazardous waste. Slag, a by-product of metallurgical and combustion processes, can also be formed from molten ash in high-capacity boiler furnaces. Slag is primarily composed of mixed oxides and can be used as aggregate in concrete, road material, ballast, and as a source of phosphate fertilizer.12

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solid-waste management
Furnace operation
…and other solid materials called bottom ash. The gaseous by-products of incomplete combustion, along with finely divided particulate material called fly ash, are carried along in the incinerator airstream. Fly ash includes cinders, dust, and soot. In order to remove fly ash and gaseous by-products before they are exhausted into…
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…and other solid materials called bottom ash. The gaseous by-products of incomplete combustion, along with finely divided particulate material called fly ash, are carried along in the incinerator airstream. Fly ash includes cinders, dust, and soot. In order to remove fly ash and gaseous by-products before they are exhausted into…
Read More