Low-grade Laterite Nickel Ore Chlorination Segregation - Magnetic Separation Process

With the high-grade nickel sulphide mining depletion, low-grade nickel laterite of increasing concern to be used. Because of the nickel laterite ore containing low-nickel ore complex composition,weathering a serious phenomenon and dealing with this type of nickel silicate minerals process is very complex and cost high,so far it has not been reasonable exploited. This thesis set one nickel laterite as raw materials, use the chloridizing segregation and magnetic separation manner to enrich the grade and recovery of nickel and cobalt. And then use the same way to employ other type of laterite to test and verify its feasibility.After analyzing the basic principles of chloridizing segregation and magnetic separation in laterite nickel ores and thermodynamics in chloride process of metal oxide, we can get that most of metal oxide can be chlorinated reacting with hydrogen chloride to generate the metal chloride.Then most of the metal chloride steam can be reducted to be metal simple substance or metal alloy in the carbon surface, and in the same time, the chloride can be reused. The last, we can get the concentrate from magnetic separation of calcine which is the product of chloridizing segregation.The domestic laterite ore aftering drying, grinding and sieving to partical siza of 0.12-0.15mm, mixed with 8% MgCl2,6% coke with partical siza of 0.18-0.25mm together, then be heated from the room temperature to reach 1000℃for 90 minute to get the calcine, the calcine is cooled, crushed and sieved to partical siza of 0.038-0.048mm to subject to a wet magnetic separation with 3000Gs sweep election then 1000Gs featured, the concentrate products can be obtained with the nickel and cobalt grade of 6.47%,0.224%, and the recovery of nickel,cobalt is 86.75% and 65.37%.Using of the manner of chlorinated segregation-magnetic to treat of other mines with three different seam of laterite nickel ore was investigated. Experimental results show that the concentrate after chloridizing segregation and magnetic separation, which nickel grade enriched 8 times higher than the raw ore material,cobalt grade enriched more than 6 times, and high-iron type of nickel laterite nickel recovery reached to more than 90%, cobalt recovery to near 70%.Technological study on chloridizing segregation and magnetic separation of low grade laterite nickel ore is effective, which can selective enrich nickel and cobalt, simultaneously reduce the grade of silicon and magnesium. It significantly lowered the use of pharmaceutical and the capacity of purification process. It makes a great significance to develop and utilize laterite nickel ore at home and abroad.