Novel Process of Ferronickel Nugget Production from Nickel Laterite by Semi-molten State Reduction

概要

論文の詳細を見る
Rotary kiln-electric furnace (RKEF) process is the main technology to deal with nickel laterite for the ferronickel alloy production in the world. However, this process needs huge amount of electric power due to the large ratio of slag to metal. Therefore, a novel process was proposed to directly produce ferronickel alloy nugget at a related low temperature from nickel laterite by the semi-molten reduction in the reactor like the rotary hearth furnace (RHF). The effects of temperature and basicity of the slag on the separation between the slag and metal were investigated, the results revealed that it is reasonable to achieve the ferronickel alloy nugget directly at 1400°C when the quaternary basicity ((mCaO+mMgO)/(mSiO2+mAl2O3)) was fixed at 0.60. Bad wettability of the refractory by the slag is good for the discharge of product from RHF and avoiding the corrosion of the slag. The high-temp wettability of refractory materials by the molten slag was also carried out with the sessile drop method, the results shows that the wettability order of the refractory by the slag from good to bad is Al2O3, MgO and graphite. It seems that the graphite is the suitable refractor material for bottom of RHF. However, the anti-oxidation of the graphite in the charging and discharging area is another potential problem which needs further study.
The Iron and Steel Institute of Japanの論文