Abstract

Industrial incineration is widely used to treat potentially toxic waste, but the resulting bottom ash poses environmental and economic challenges. This study was motivated by the need to assess the potential reuse of bottom ash in sustainable applications. The working hypothesis was that quenching could influence ash homogeneity, trace metal distribution, and valorisation potential. Bottom ash samples were analysed for chemical composition, trace metal content, organic carbon, particle size, density, and mineralogical structure. Results show that the ash is mainly composed of iron, aluminium, silicon, and calcium oxides, with moderate organic content. Quenched bottom ash exhibited a more uniform particle size distribution, reduced variability in several trace metal concentrations, and higher particle density compared with dry bottom ash. Statistical analysis showed reduced variability of chromium, nickel, cadmium, lead, and zinc after quenching. However, the results should be interpreted with caution due to the limited sample size and ash heterogeneity. Mineralogical analysis revealed ceramic fragments, glass phases, ferrous materials, and residual carbonaceous fractions. Quenching improved material homogeneity and indicates potential for reuse in construction applications. However, no leaching tests were performed; thus, environmental stability and mobility remain unconfirmed.