High-Performance, Eco-Friendly Blocks from Iron Ore Tailings: A Solution for Sustainable Construction

Goa’s iron ore mining industry has generated over 7.7 million tonnes of iron ore tailings (IOTs) in the past two decades. These IOTs pose a significant environmental threat due to heavy metal contamination, dust generation, and acid mine drainage. While some IOTs are used for backfilling, the majority are stored in tailings storage facilities (TSFs), posing long-term risks to surrounding water resources, ecosystems, and land use. Large-scale utilization technologies are crucial for sustainable IOT management. This study investigates the feasibility of incorporating IOTs in construction block production, aiming for high-volume waste consumption and improved resource efficiency. This approach offers a potential pathway to remediate the environmental impact of IOTs. The proposed method replaces 85% of the cement content with a cementitious material comprising 65% Ground Granulated Blast Furnace Slag (GGBS), 10% Fly Ash, and 10% Lime. It also utilizes IOTs entirely as a substitute for sand, with ceramic waste partially replacing coarse aggregates. While partial substitution of coarse aggregates with ceramic waste was attempted, it decreased workability. The optimal mix design, achieving the highest compressive strength, utilizes 15% cement, 65% GGBS, 10% Fly Ash and Lime, and 100% IOTs as fine aggregate with 100% basaltic aggregates. This formulation successfully demonstrates the potential use of IOTs in manufacturing construction blocks that reach compressive strengths of 10.91 N.mm-² and 15.92 N.mm-² at 7 and 28 days, respectively, satisfying the IS 2185-Part 1 (2005) code requirement. The block density was 2.20 g.cm-³. This research demonstrates the potential to convert a significant environmental challenge into a sustainable solution. By utilizing IOTs in construction block production, we can effectively achieve waste remediation; and create resource-efficient and eco-friendly building materials, offering substantial dual benefits for Goa’s environment and construction sector.