Valorization of Incinerated Biomedical Waste Ash in Cementitious System: A Comprehensive Review

Abstract

Disposing of incinerated biomedical waste ash (IBWA) contaminated with heavy metals (e.g., Cr, Zn, Pb) poses significant environmental and public health concerns, necessitating innovative and sustainable management strategies. Cement-based solidification emerges as a promising approach to repurpose IBWA by effectively immobilizing heavy metals and mitigating their ecological footprint. However, broader industrial and societal acceptance of IBWA as a substitute for cement and sand remains constrained owing to limited quantification of IBWA availability and safety concerns. In this perspective, the current paper presents a global database on IBWA availability and maps the geographic distribution of biomedical waste incinerators in India. It also comprehensively reviews IBWA’s potential in mortar/concrete, focusing on its physico-chemical, leachability, hydration, mechanical, durability, and microstructural properties. The study further highlights the importance of a cradle-to-gate and gate-to-gate Life Cycle Assessment (LCA) to holistically assess the environmental performance of IBWA-incorporated mortar systems, promoting circular economy principles and resource efficiency in the construction sector. IBWA, with its high SiO₂ and CaO content (> 50%), exhibits latent hydraulic properties suitable for construction applications. The porous cellular structure of IBWA can lead to increased porosity and water absorption in concrete. Leachate analysis demonstrated the effective stabilization of heavy elements within the cement hydration matrix (C-S-H, C-A-S-H, etc.), meeting US EPA regulatory standards. LCA interprets that IBWA utilization of up to 10% cement replacement material and 30% sand replacement material could curtail the carbon footprint and energy demand by ~ 25–35% and 15–25%, respectively, compared to conventional cement-based mortar systems. These findings highlight IBWA’s potential to transform the construction sector, aligning it with global sustainability goals and reducing its dependence on non-renewable resources. © The Author(s), under exclusive licence to Shiraz University 2025.