Circular and Sustainable Approaches for the Management and Treatment of Incineration Bottom Ash

Hazardous wastes containing heavy metals, such as incineration bottom ash (IBA) from industrial waste incinerators, typically require stabilization with costly chemical reagents prior to disposal in non-hazardous waste landfills. This study explores a more sustainable and circular treatment strategy aimed at rendering IBA suitable for disposal in landfills designated for stable, non-reactive waste. The proposed process involves an initial extraction step using sodium hydroxide (NaOH) at varying concentrations (0.5 M, 1 M, and 2 M), followed by a washing phase. Uniquely, landfill leachate—a waste by-product itself—was employed both as a diluent in the extraction solution and as a washing agent, thereby minimizing the use of freshwater resources. Experimental results confirmed the effectiveness of the treatment in meeting regulatory limits, paving the way for the development of circular and sustainable approaches for the management of hazardous industrial waste.