Abstract:After the high-pressure acid leaching process for extracting nickel and cobalt from laterite nickel ore, a large amount of waste residue is produced, which contains valuable elements such as iron, nickel, cobalt, manganese, chromium, and rare earths. Among them, iron is a dominant resource, with a content of 40% to 60%, primarily existing in the form of hematite. However, this residue is characterized by fine particle size, complex mineral distribution relationships, and high sulfur content, making it extremely difficult to process. Currently, the main disposal method for leaching residue of laterite nickel ore is tailings pond storage, which not only incurs high construction costs but also wastes resources and poses significant risks of dam failure. Research on treatment methods for this residue primarily focuses on producing iron concentrate, molten iron, construction materials, and high-value-added materials. The magnetization roasting-magnetic separation method for producing iron concentrate offers advantages such as low energy consumption and simple processing, but the challenge of comprehensive tailings utilization remains unresolved. The reduction smelting method for producing molten iron is highly operable and achieves high recovery rates for iron and sulfur, but it suffers from high energy consumption, and its economic viability fluctuates with iron ore prices. The preparation of construction materials from leaching residue is simple and suitable for large-scale production, but it remains at the experimental research stage due to limitations imposed by the residue’s composition and properties. The production of battery materials from leaching residue offers high resource utilization and significant product value, but it involves lengthy processes, high acid/alkali consumption, and high equipment requirements. Finally, this paper puts forward suggestions for future resource recovery and utilization of leaching residue: broaden comprehensive utilization pathways by co-processing with other industrial waste to achieve waste treatment with waste; strengthen technological coupling and innovation to improve overall utilization efficiency; and develop new technologies, reagents, and equipment to promote high-value utilization of leaching residue.
