Wet smelting method of nickel oxide ore

Abstract

In the wet smelting method of nickel oxide ore performed by high temperature compression acid, because most of the iron ore is fixed into an immersion residue in the form of red iron ore, it can achieve the oxidation rate of high -speed rail and suppress the amount of sulfuric acid during immersion.Make nickel and cobalt immersion at a high immersion rate.Measure the carbon grade and flow in the ore pulp prepared in the 1st process, and find the carbon capacity of the second process in the second process. Then, in the second process of adding high -pressure air and high -pressure water vapor to implement it.Adjust the proportion of high -pressure air and high -pressure oxygen to make its oxygen purity reach 21 to 60 %, and while maintaining the purity of the oxygen, the oxygen blowing amount is relative toThe weight of each 1T carbon of the process is 200 to 600nm3, and the ORP (based on AG / AGCL as the benchmark) in the immersion process is 400-650mv.

Description

technical field [0001] The invention relates to a wet smelting method of nickel oxide ore recovered by leaching nickel and cobalt from the nickel oxide ore with acid under high temperature and pressure. This application claims priority based on Japanese Patent Application No. 2013-056012 filed in Japan on March 19, 2013, and Japanese Patent Application No. 2013-195610 filed in Japan on September 20, 2013. This application is incorporated herein by reference. Background technique [0002] Conventionally, as a smelting process for separating and recovering nickel and cobalt from iron from a nickel oxide ore containing iron as a main component and containing 1 to 2% by weight of nickel, for example, dry smelting or reduction Roasting-leaching method, the dry smelting method is: roasting nickel oxide ore, reducing and sulfiding the nickel component, and then smelting to produce matte containing nickel sulfide; the reduction roasting-leaching method is: After the nickel oxide o...

AI Technical Summary

Problems solved by technology

In order to remove the hexavalent chromium in the neutralization treatment process or wastewater treatment process of the subsequent process, it is necessary to use a reducing agent to reduce it to trivalent chromium, which will inevitably lead to an increase in smelting costs

If the reduction treatment is not performed, the following problems may occur: the nickel or cobalt product contains chromium as an impurity, or chromium remains in the final solution of the wastewater treatment

On the other hand, if the oxidation-reduction potential at the time of leaching is too low, problems occur in that titanium used for autoclaves as a corrosion-resistant material is deteriorated, and high-temperature thermal hydrolysis reaction of iron is inhibited, so that a large amount of iron remains in the leaching solution. The amount of iron in the neutralization treatment process of the subsequent process will increase the co-precipitation amount of nickel and cobalt, that is, the loss will increase

However, depending on the type of ore, their composition or organic component content fluctuates. Therefore, not only the blending ratio is restricted, but also the grade of magnesium and aluminum in the solid content of the ore slurry is increased according to the mixing ratio.

Impurities such as these magnesium or aluminum react with the sulfuric acid added in the acid leaching of the second step, and the sulfuric acid will be consumed, so the leaching rate of nickel and cobalt is reduced.

In order to avoid the above phenomenon, it is necessary to add an excessive amount of sulfuric acid, but in this case, the following problems will occur: the amount of chemical agent in the neutralization treatment process in the subsequent process will increase, and the coprecipitation amount of nickel and cobalt will increase.

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