Utilization of municipal solid waste incineration ash in concrete: A feasibility and environmental assessment

The exponential rise in municipal solid waste (MSW) and the environmental toll of conventional concrete production have posed serious sustainability challenges in India. This study explores the feasibility of utilizing Municipal Solid Waste Incineration (MSWI) bottom ash as a partial replacement for fine aggregates in M30 grade concrete, aiming to reduce both construction-related emissions and landfill dependency. The ash, sourced from the Okhla Waste-to-Energy Plant, underwent a comprehensive pre-treatment process including washing, sieving, thermal stabilization, and chemical treatment to ensure environmental safety and material compatibility. Concrete specimens were prepared with 0%, 10%, 15%, and 20% bottom ash replacement. Results revealed that up to 15% substitution maintained desirable mechanical strength, with compressive strength exceeding 37 MPa and adequate tensile and flexural performance. Durability assessments-including water absorption, acid resistance, and sulfate resistance-confirmed structural integrity and resistance to aggressive environments. TCLP leaching tests validated the environmental safety of the treated ash.