Preliminary Study on the Toxicity and Recycle ability of Municipal Solid Waste Incineration Ashes

Preliminary Study on the Toxicity and Recycle ability of Municipal Solid Waste Incineration Ashes

Since 1990, the Taiwan government started to treat the municipal solid waste (MSW) either by incineration and land-filling, in which the incineration is more favor. Until now there are 21 large scale municipal solid waste incineration plants (MSWI) to recycle the valuable metals and energy from wastes. About 80% of original MSW is burned out in the MSWI, the un-combustible parts of MSW have become ash wastes MSWI, for example fly ash (including the scrubber residue and baghouse ash or electrostatic ash) and bottom ash. Figure 1 shows the flow chart of flue gas treatment and ash waste generation units in the MSWI equipped a semi-dry de-SOx and NOx system. Among these wash wastes, fly ash containments dioxins and heavy metals, it is classified as hazardous materials; while the bottom ash is classified as non-hazardous materials and general industrial wastes, due to that it is fully filled the regulation of toxic characteristic leaching procedure (TCLP) test.