Silicomanganese fume for sustainable construction: a recent review, ecological assessment, and future research roadmap

The lack of periodic safe disposal of silico-manganese wastes poses significant environmental and health risks. Producing each ton of silico-manganese alloy results in more than one ton of slag and 10%–15% fume, which can supplement cement in concrete. This study presents the first critical review of silicomanganese fume (SiMnF) for the synthesis of cementitious composites and evaluation of engineering properties. The review covers the fresh, hardened, and durability characteristics, along with the microstructural development of SiMnF-based Portland cement and alkali-activated products. It also examines the synergistic effects of SiMnF with other supplementary cementitious materials, focusing on rheological and mechanical aspects. The findings indicate that pre-treatment of raw materials and post-treatment of composites are essential for achieving target properties. Optimized dosage of SiMnF, alkaline activator concentration, and curing conditions can provide workable mixes with compressive strengths of up to 50 MPa. A detailed life-cycle assessment was conducted to quantify the environmental impact of SiMnF-based mixtures. Based on identified knowledge gaps, the study proposes a roadmap for future research. This review highlights the strategies for SiMnF from ferroalloy plants to be used in the cement and concrete industries, promoting solid waste management, reducing carbon footprints, and supporting sustainable development towards net-zero emission targets.