Abstract
The stabilization of arsenic-bearing residues from metallurgical operations is a critical environmental challenge. DUNDEE Sustainable Technologies’ GlassLock™ vitrification technology provides a robust solution by incorporating arsenic into a chemically durable glass matrix, ensuring long-term containment and compliance with regulatory leaching standards. This study investigates the substitution of conventional silica with tailings from a legacy arsenical flue dusts project as a primary raw material in glass formulations, aiming to enhance sustainability, and reduce costs and reliance on off-site glass making reagents. Experimental trials produced two formulations: DST10-2024, with complete silica replacement by tailings, and DST11-2024, with partial substitution. Both were evaluated for leach resistance using the EPA 1311 Toxicity Characteristic Leaching Procedure (TCLP), where the EPA Regulatory Limit for arsenic is 5.0 mg/L, and for physical properties relevant to handling and processing. Results indicate that partial substitution (DST11-2024) achieved superior performance, with arsenic leachability significantly reduced compared to full substitution. Specifically, DST10-2024 exhibited a TCLP arsenic concentration of 3.76 mg/L, while DST11-2024 achieved 1.06 mg/L, meeting stringent environmental performance targets while maintaining structural integrity and operational feasibility. The findings demonstrate that integrating flotation tailings into vitrification processes can deliver multiple benefits: improved environmental compliance, valorization of mine residues, and potential reductions in operating costs. This approach supports circular economy principles by transforming waste into feedstock, minimizing environmental liabilities, and reducing the demand for off-site glass making reagents. In addition to technical performance, the study highlights the importance of engineering assessments to quantify economic and operational impacts. Such evaluations will inform decisions on process design, reagent consumption, and equipment sizing for industrial deployment. By coupling environmental stewardship with resource efficiency, this work positions GlassLock™ as a viable solution for sustainable remediation strategies.