Eco-concrete for sustainability: utilizing aluminium dross and iron slag as partial replacement materials

Emphasis on utilizing the industrial waste/discarded materials can be brought about by discovering innovative methods of disposal. One such a way of waste disposal can be through utilizing them in concrete production as a filler material or pozzolana. In this regard, the present study proposes to use the aluminium dross and granular iron slag as partial replacement materials for cement and natural sand, respectively, to develop eco-concrete. Nine mixes were produced with different proportions of cement, aluminium dross, sand and granular iron slag content. The aluminium dross was replaced at 5, 10, 15 and 20% of the weight of the cement. Initially, the optimal substitution percentage of aluminium dross was found without the substitution of iron slag based on the strength results. Later, by adopting the optimal aluminium dross percentage with cement, the granular iron slag was partially substituted at 10, 20, 30 and 40% of natural sand to find the overall optimal blend. The strength and durability properties of the M40 grade concrete employing these two admixture combinations were analysed. It was noticed that the strength and durability properties of the eco-concrete produced by incorporating aluminium dross −5% and iron slag −20% were comparable to that of conventional concrete. Furthermore, from the toxicity analysis, it was seen that the leaching of heavy and trace elements from the eco-concrete was negligibly small and within the limits. In near future, the cost-effective, eco-friendly materials and technologies can be opted as a perpetual strategy to overcome severe material shortages for resource conservation and economy.