Answers · Environment and permitting
What is the difference between fly ash and bottom ash?
Short answer
Bottom ash is the heavier residue collected at the combustion chamber. Fly ash consists of fine material captured from the flue gas, sometimes reported together with residues from air pollution controls.
Request separate figures
Ask how the facility reports each residue and where it goes. Track the tonnes generated, treated, sent for recovery, and disposed. Check whether figures are on a dry or as-received basis.
Check the applicable decision
Rules depend on jurisdiction, waste classification, and the proposed use. Use the facility permit, analytical testing and regulator decision to establish the disposition of each ash stream.
Sources
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