Simplified framework for efficient utilization of municipal solid waste incinerator bottom ash as construction material via systematic classification and characterization

Abstract

The incinerator bottom ash (IBA) constitutes approximately 80% of the municipal solid waste (MSW) incineration residues. To minimize the end-waste, one of the sustainable solutions is to utilize IBA. IBA is often utilized directly with or without simple pre-treatment after receiving from the incineration plant. However, the significant heterogeneity in the physicochemical composition of the IBA has hindered its widespread utilization. The given study proposes a simplified framework to improve the utilization efficiency of IBA via a systematic classification and characterization approach. The IBA was classified into ten classes (classified IBA) according to the four particle size ranges and three mineralogical categories. A comprehensive characterization of chemical/mineralogical compositions of classified IBA using state-of-the-art techniques was then conducted to understand the properties of each class, which aid in determining the appropriate applications for each category of classified IBA. The leaching behavior of the classified IBA was also studied to evaluate the environmental safety of the classified IBA classes and suggested avoiding categories with high concentrations of leachable toxic elements. The framework developed in this study for efficiently utilizing IBA is demonstrated for IBA collected from a local incineration plant.