Nickel oxide ore dressing process

Abstract

The invention provides a concentration technology of nickel oxide ore. The concentration technology includes the following steps: material proportioning and granulation: nickel oxide ore is carried out bypass-recrushing and sifting so as to obtain fine ore which is carried out ore proportioning to obtain mixed mine, the mixed mine cooperates with a reducing agent and a flux to obtain mixed material which is further pelletized to obtain green pellets; reduction and roasting: the green pellets are put in roasting equipment to carry out reduction and roasting to obtain roasted pellets; protective quencher is carried out to the roasted pellets; magnetic concentration: after cooling off the roasted pellets, by ball milling and sifting, fine ore is obtained and put into magnetic-selection equipment to carry out magnetic concentration, and initial concentrate is obtained by magnetic concentration; and electrical selection: SiO2 is removed from the initial concentrate by electrical selection and final concentrate is obtained. The concentration technology is favorable to blast furnace ferronickel smelting with large scale, high efficiency and low energy consumption, has short technological process, low cost, notable anaphase economic benefits and strong controllability, and is favorable to refining nickel oxide ore and saving energy and reducing emission.

Description

technical field [0001] The invention relates to a beneficiation process, in particular to a nickel oxide ore beneficiation process. Background technique [0002] Due to differences in ore-forming conditions, nickel oxide ores are divided into two categories according to mineral types: one is nickel-containing limonite, which is high in iron and low in silicon and magnesium, and its chemical formula is (Fe, Ni)O(OH) nH 2 O; the second is silicon-magnesium-nickel ore, low in iron and high in silicon and magnesium, and its chemical formula is 4 (Ni, Mg) 4 · 3SiO2 2 ·6H 2 O and H 2 (Ni,Mg)SiO 4 mH 2 O; The nickel oxide ore imported in large quantities in China mostly comes from the Philippines, Indonesia, Australia and other countries, and its composition fluctuates widely. Among them, the iron content of nickel-containing limonite is about 20-47%, and the nickel content is 0.6-1.6%. around, SiO 2 At about 10%, MgO is about 6.0%; Simagnesian ore contains about 10-20% iron...

AI Technical Summary

Problems solved by technology

[0003] Because nickel in nickel oxide ore is often dispersed in gangue minerals in the same quality and shape, the particles are very fine, the traditional enrichment method is smelting enrichment, pyrometallurgy enrichment includes matte smelting method, ferronickel method, granular iron Hydrometallurgy enrichment can be divided into normal pressure ammonia leaching method and high pressure acid leaching method, etc.; these methods have their own characteristics and disadvantages, such as the low recovery rate of granular iron method, and the iron Low recovery, high power consumption, low cobalt recovery by atmospheric pressure ammonia leaching, high pressure acid leaching is suitable for treating nickel oxide ore with low silicon and magnesium;

[0004] Most of the above-mentioned processes are crushed and screened raw ore directly into the flow process for processing, so in the blast furnace smelting, the smelting efficiency is low, the energy consumption is high, and the waste of ore resources is serious, which is not conducive to the refining of nickel oxide ore with different components, which is not conducive to Large-scale ferronickel smelting; although the atmospheric pressure ammonia leaching method uses chemical selection and reduction roasting to increase the leaching rate, its basic feature is high CO 2 % / CO% ratio and medium temperature control, the medium temperature is controlled at 710°C--730°C, the purpose is to promote nickel and suppress iron