Removal of carbon constituents from hospital solid waste incinerator fly ash by column flotation

► A two-stage flotation process for HSWI fly ash treatment is proposed, which is efficient. ► Column flotation can simultaneously separate carbon constituents and PCDD/Fs from HSWI fly ash. ► The large amounts of NaCl and powder activated carbon in fly ash have effects on flotation process. ► The flotation process of fly ash is favorable to safe disposal of the final products at low cost.