Laboratory-scale smelting of limonitic laterite ore

Nickel laterites, particularly limonitic ores, historically have low nickel content and were regarded as unsuitable for certain pyrometallurgical treatments; however, recent projects aim to adapt these methods for low-grade ores due to advancements in technology and changes in market demand. This study investigates the feasibility of producing ferronickel from low-grade limonitic laterite ore while addressing nickel losses during the smelting process, a significant challenge in ferronickel production. Laboratory-scale experiments were conducted to evaluate the efficiency of nickel recovery and the influences of slag composition on losses. The findings reveal that despite the traditional view of limonitic ores necessitating hydrometallurgical techniques, the new pyrometallurgical approaches are viable, especially given improvements in furnace technology that mitigate previous inefficiencies and reduce energy costs. With suitable processing conditions, nickel contents above 1% can be economically treated, suggesting that the industry may progressively shift towards lower-grade deposits as higher nickel prices and technological advancements change production dynamics. These results provide insight into optimizing ferronickel production processes, ultimately contributing to the sustainable management of nickel resources in light of declining high-grade reserves.