Performance and risk assessment of alinite cement-based materials from municipal solid waste incineration fly ash (MSWIFA)

Abstract

Municipal solid waste incineration fly ash (MSWIFA) can pose serious threats to the environment due to the leaching of heavy metals, chlorinated organic compounds, sulfur compounds, dioxins etc. In a laboratory study, MSWIFA was successfully used as raw material in sintering and in the creation of a type of alinite cement. The compressive strength, durability, and risk assessment of the prepared alinite cement-based materials were evaluated. The compressive strength of the alinite cement containing 3–5 % gypsum can excess that of the control cement. It also has excellent resistance to carbonation, water permeability, and sulfate attack. Dry shrinkage properties, however, are inferior to the control cement. The content of soluble chloride ion from alinite cement during its hydration may potentially accelerate the corrosion of steel bars in concrete. Thus, it is not recommended for use in steel-reinforced concrete. The environmental risk assessment indicates alinite cement-based materials exhibit stability and long-term safety, and the possibility of secondary pollution to the environment is considered negligible. We conclude that alinite cement is a way that can be prepared for proper disposal and/or beneficial reuse of MSWIFA.