Analysis the effect of charcoal mass variation to ni content, sinter strength and yield on sintering process of limonitic laterite nickel ore

The depletion of sulfide nickel ore and the growing of stainless steel demand each year cause the use of low-grade laterite nickel ore continues to increase. Due to very low nickel content, there is no optimal process to extract them. One of the alternative processes being developed now is the sintering-blast furnace process which produces Nickel Pig Iron (NPI). This research was conducted by sintering limonitic laterite nickel ore using charcoal as fuel and limestone as a flux. This research aims to analyze the effect of charcoal mass variation on Ni content, sinter strength, and the yield on the sintering process of limonitic laterite nickel ore. Charcoal and limestone demand calculated using energy balance and mass balance, then varied charcoal mass to feed material. Feed materials are fed in the furnace, heated at a temperature of 1200oC with 4 hours holding time. Next, the sinter yield was calculated. EDX, XRD, and Drop tests were also performed to determine Ni content, sinter compounds, and strength. The highest Ni content was 3.66% which was obtained by adding 9.9 kg charcoal. The highest sinter strength and yield also obtained by adding 9.9 kg charcoal (72.30% and 86.44%, respectively). Mayor phases which formed on sinter with 9.9 kg charcoal addition is nickel-iron oxide.