| 摘要 |
PURPOSE:To produce concentrate contg. nickel oxide at a high ratio at a good yield by pelletizing nickel oxide ore together with a halide and carbonaceous reducing agent and subjecting the pellets to chlorination reduction roasting, then pulverizing the pellets and subjecting the powder to a wet process magnetic sepn. treatment. CONSTITUTION:The halide, such as CaCl2, and the carbonaceous reducing agent, such as coke, are mixed with the powder of the nickel oxide ore contg. FeO and a small amt. of Ni0 and the mixture is formed to the pellets sized 3 to 15mm in diameter. The pellets are put into a horizontal type rotary kiln and are subjected to the chlorination reduction roasting at 900 to 1100 deg.C to reduce the NiO and the FeO to Ni and Fe. These pellets are then charged into a vertical furnace in order to further improve a reducibility at need. The reduction reaction is accelerated by blowing an H2-contg. reducing gas having >=60% ratio of H2/(H2+H2O) into the kiln from the bottom. The pellets are then pulverized and the power is made into a slurry by water. This slurry is processed by the wet process magnetic separating machine, by which the Ni0 in the nickel oxide ore is recovered as the Ni at the excellent yield. The concentrate having the high Ni grade is thus inexpensively produced, by which the Fe-Ni raw material is obtd. |
