Sulfidation treatment of molten incineration fly ashes with Na2S for zinc, lead and copper resource recovery

Two-Step Flotation Treatment for Removal of Toxic Matter from Hospital Solid Waste Incinerator Fly Ash

“…4. With the extension of time, sulphidation efficiency steeply increased and reached to the maximum within 30 min, in which the conversion extent for Zn, Pb, and Cu were 85.5%, 72.8% and 77.6%, respectively, and it then flattened from 30 min to 1 h. The result was consistent with the literature of Kuchar (Kuchar et al, 2007b). This may be attributed to the rapid reaction of freely soluble metal oxides and hydroxides within 30min.…”

“…The content of heavy metals in the concentrate reached up to 90.9 g kg -1 for Zn, 17.5g kg -1 for Pb and 8.2 g kg -1 for Cu which correspond to the metal concentrations in natural ores and thus can be recycled as raw ores (Richard et al, 2009;Deliyanni et al, 2017). Kuchar reported that 1%-10% of Zn, 1%-5% of Pb and 0.5%-1.0% of Cu remain in mined natural ores (Kuchar et al, 2007b) ) and can be directly sent to waste incineration plant wastewater treatment system for centralized treatment. The next stage of the research will consider the whole process, including the recirculation of the effluents produced.…”

Immobilization of Cu(II) and Zn(II) in simulated polluted soil using sulfurizing agent

“…This meant sulfide precipitates were generated after mixing soil with an aqueous solution of Na 2 S, and the immobilizing product was a mixture of CuS and ZnS. Such result was consistent with that reported by Kuchar [31]. Namely, heavy metals were converted into insoluble metal sulfides by sulfidation reaction, which was shown in Eq.…”

Effect of water quenching and SiO2 addition during vitrification of fly ash

“…Evaporation orientation metals contained in the secondary fly ash, such as Pb and Zn, can be recovered following a procedure, including extraction by acid, concentration sedimentation and refinement [9]. The ingot can be sent to a smelter to recover Fe or other metals with a large specific weight.…”