Utilisation of biomass waste as a reductant in the smelting of saprolitic nickel ore using a DC-arc furnace

In this work, the biomass charcoal from rubber wood, coconut shell, corn cob, palm kernel shell, as a reductant in the smelting process of saprolitic nickel laterite has been observed in a laboratory submerged arc furnace. A total of 5 kg of saprolite, some reductant and limestone were smelted together in this furnace, which was adjusted to 0.8 of carbon stoichiometric and 0.8 of slag basicity. The smelting process was carried out for 1 h, and the pouring temperature was 1400 °C–1500 °C. From the result, the smelting process using corn cob charcoal and palm kernel shell charcoal showed almost similar nickel grade and recovery compared with using coke as a reductant, which is above 12% and 90%, respectively. It also has the same slag phase, that is, diopside, with a low melting point. These two types of biomass waste reductants could be replaced using coke in the future.