Environmental Release Characteristics of Heavy Metal Elements in Typical Antimony Metallurgical Solid Wastes

Objective To systematically evaluate the release characteristics of heavy metal elements in water-quenched slag, arsenic-alkali slag and lead removal slag produced by antimony pyrometallurgical smelting at different environmental conditions, and to provide a scientific basis for their environmental pollution prevention and harmless disposal, Methods the chemical elements and phase composition, leaching toxicity and environmental release characteristics were studied. Result Water-quenched slag contains a small amount of antimony (1.47%), while the concentration of the main heavy metals in the water-quenched slag does not exceed the national standard limit, but the leaching concentration of Sb element is higher. The main elements of arsenic-alkali residue include As (15.68%), Sb (16.78%), and arsenic-alkali residue toxicity test shows that As, Se element leaching toxicity exceeds the standard limit, and Sb element leaching concentration reaches 255.87 mg/L, far exceeded the "Emission standards is of pollutants for stannum, antimony and mercury Industries GB 33770-2014" in the Sb element emission limits (1 mg/L). In addition to the lead slag in the Pb, Cd leaching concentration of the elements exceeded the standard, Sb leaching concentration of 354 mg/L, with a very high degree of environmental hazards. Conclusion Among the three typical solid wastes, water-quenched slag has relatively low environmental risks. However, the leaching concentrations of As, Se, and Sb in arsenic-alkali slag, as well as Pb, Cd, and Sb in lead removal slag, all seriously exceed the standards, posing extremely high environmental hazards and urgently requiring harmless disposal and resource utilization.