Recycle Option for Municipal Solid Waste Incineration Fly Ash (MSWIFA) as a Partial Replacement for Cement in Mortars Containing Calcium Sulfoaluminate Cement (CSA) and Portland Cement to Save the Environment and Natural Resources

Reduction of emissions, energy consumption, and use of substitutes for natural resources is an element of sustainable development and the circular economy. Cement production is a process with a high carbon footprint; therefore, minimizing the use of this material has a significant impact on reducing environmental costs. A substitute for cement is municipal solid waste incineration fly ash (MSWIFA). The article presents a method of making an eco-concrete with the use of municipal solid waste incineration hazardous fly ash. The use of secondary waste for the production of building materials additionally contributes to achieving climate neutrality established by the European Union and China. The article analyzes the physicochemical properties of various MSWIFAs, the amount and leachability of heavy metals, and selected elements from MSWIFA and concrete properties. The technical properties of mortars containing MSWIFA were investigated. Consistency is not affected by MSWIFA content, although the workability time is prolonged. Air entraining admixture efficiency is lowered, but the effect lasts longer. The initial setting time is prolonged, and the flexural and compressive strengths are decreased in early terms because of the zinc presence in MSWIFA. MSWIFA does not influence the water demand, volume stability of mortars, or microstructure of cement's hydration products.