Evaluating the recycling potential of ashes discharged from waste incineration facilities and its dependency on pretreatment efficiency in Korea

The amount of incineration ash (IA) is expected to increase in South Korea from the rapidly rising numbers and operation capacities of incineration facilities; therefore, it remains necessary to establish measurements for the enhanced recycling and circularity of IA. This study established a database of hazardous substances in IA by compiling discharge data and survey results from domestic incineration facilities, along with literature survey values. The recycling potential of IA was assessed considering leaching reduction efficiency of various pre-treatment methods. In particular, 98.2% of bottom ash and 49.0% of fly ash satisfied the IA recycling criteria after melting. Also, when mixed at a ratio of similar to 78:22 natural soil to IA, the resulting material was usable for media-contact recycling by meeting the heavy metal content criteria of the Soil Environment Conservation Act.

Automated summary

With the increasing numbers and operation capacities of incineration facilities in South Korea, it is necessary to establish measurements for enhanced recycling and circularity of incineration ash (IA). This study compiled discharge data, survey results, and literature survey values to establish a database of hazardous substances in IA. Leaching reduction efficiency of various pre-treatment methods was considered to assess the recycling potential of IA. Particularly, after melting, 98.2% of bottom ash and 49.0% of fly ash satisfied the IA recycling criteria. Additionally, when mixed with natural soil at a ratio of approximately 78:22, the resulting material met the heavy metal content criteria for media-contact recycling according to the Soil Environment Conservation Act.