KR101867739B1 - Method for manufacturing nickel concentrate - Google Patents

Abstract

The present invention relates to a method for manufacturing Ni concentrate. More specifically, the present invention relates to a method for manufacturing Ni concentrate with high Ni concentration from an Ni material such as FeNi. According to the present invention, the method comprises the following steps of: preparing a raw material of FeNi; adding the raw material of FeNi to an ammonium chloride solution to manufacture processing water; injecting gas containing oxygen to the processing water; adding acid to the processing water so as to release Ni; adding an oxidizing agent to the processing water; and separating a solid phase from the processing water to gain Ni concentrate.

Description

[0001] METHOD FOR MANUFACTURING NICKEL CONCENTRATE [0002]

The present invention relates to a method for producing a Ni concentrate, and more particularly, to a method for producing a Ni concentrate having a high Ni concentration from a Ni-based material such as FeNi.

Generally, Ni is produced by wet smelting from minerals called Limonites. In addition to Ni, a large amount of Fe is contained in the limonite minerals. Such Ni-based materials have a FeNi composition in general.

As an example, Korean Patent Registration No. 10-1353721 discloses a method of removing limonite raw material to remove moisture, raising the content of Ni through firing process, reducing the Fe and Ni in the rumonite raw material in a hydrogen reducing atmosphere A process for producing the metal is disclosed.

However, since the material produced by this process is FeNi containing a large amount of Fe, there has been a problem that its use is limited so that it is always used in fields requiring Fe together. Further, even if Fe is required together, there is a limitation also in controlling the composition of water (product) produced from FeNi.

Disclosure of Invention Technical Problem [8] The present invention has been made to solve the above problems of the prior art, and one aspect of the present invention provides a method for producing a Ni concentrate, which is a raw material for producing water mainly containing Ni.

The problem of the present invention is not limited to the above-mentioned range. Those of ordinary skill in the art will appreciate that there is no difficulty in understanding the additional task to be solved by the present invention from the overall description of the present invention.

A method for producing a Ni concentrate to solve the problems of the present invention includes the steps of preparing a FeNi raw material; Adding the FeNi raw material to an ammonium chloride aqueous solution to prepare a process water; Injecting an oxygen-containing gas into the process water; Adding an acid to the process water to elute Ni; Adding an oxidizing agent to the process water; And separating the solid phase from the process water to obtain a Ni concentrate.

The present invention can provide a method for producing a Ni concentrate capable of obtaining a Ni raw material having a limited restriction on the use of Ni by performing a process of de-ironing from a raw material containing Fe and Ni at the same time.

1 is a process flow diagram schematically illustrating a method for preparing a Ni concentrate according to one embodiment of the present invention,
Figure 2 is a process flow diagram illustrating a method of making a FeNi raw material powder used in one embodiment of the present invention.

Hereinafter, the present invention will be described in detail.

FIG. 1 schematically shows a method for producing the Ni concentrate of the present invention. It should be noted, however, that Fig. 1 is only an exemplary embodiment of the present invention and should not be used as a standard for determining the scope of rights of the present invention. Each step described in FIG. 1 does not necessarily have to follow the order, but may be modified and applied in various ways. It should be noted that, for convenience of explanation, the first and second de-ironing processes will be described below. However, it should be noted that the first and second processes do not necessarily mean the order of the first and second processes. As shown in FIG. 1, the present invention uses a method of preparing Fe (raw material) containing Fe and Ni (FeNi raw material) and then de-ironing Fe in the raw material. (Fe ^{2 +} ) and nickel ions (Ni ^{2 +} ) are leached from the FeNi raw material by using an acid as a generally used method. However, in this method, but, Fe ^{2 +} only be selectively removed, but to obtain the Ni, in order to selectively remove the Fe ^{2 +} requires oxidation process for oxidizing to Fe ^{3 +} to form an insoluble compound, and Fe is oxidized for this oxidation process ^{2 + < / RTI &gt}; However, the present invention is an invention capable of selectively removing Fe from solid FeNi, which is advantageous in that a large amount of neutralizing agent is not required.

That is, in the present invention, the FeNi raw material is added to an ammonium chloride aqueous solution to first dissolve and remove Fe contained in the raw material (primary de-ironing). In the present invention, an ammonium chloride aqueous solution is used as a basic starting material for the process water used in the whole process. That is, when the FeNi raw material is dissolved in an aqueous solution of ammonium chloride to prepare a process water, Fe is eluted into Fe ^{2 +} state in the process water, and Ni remains in the raw material. In the subsequent steps, the composition of the process water may be changed by adding various additives such as an acid, a neutralizing agent, and an oxidizing agent. However, it should be noted that the present invention refers to the process water as a whole.

To induce a sufficient reaction, the concentration of ammonium chloride in the aqueous ammonium chloride solution may be 0.4 wt% or more. As the concentration of ammonium chloride is increased, the reaction is promoted, so the upper limit is not particularly limited. However, if the concentration exceeds 4 wt%, the increase of the effect is weak and the cost may increase. Therefore, the upper limit may be limited to 4 wt% have.

The mass of the aqueous ammonium chloride solution may be 2 to 8 times the mass of the raw material FeNi (based on the mass of the aqueous ammonium chloride solution without FeNi added). That is, in order to obtain a sufficient reaction effect, the mass of the ammonium chloride aqueous solution may be more than twice the mass of the raw material. Also, if the amount of the aqueous ammonium chloride solution is too high, the effect can no longer be expected to increase and the cost may increase, so that in one embodiment, the amount of aqueous ammonium chloride solution can be determined to be 8 times the mass of the raw material.

In addition, the content of Ni in FeNi used as a raw material may be limited to 20 wt% or more. When the Ni content is too low, the Ni content in the resulting concentrate may not be high and may not be effective, so that the Ni content is advantageously 20 wt% or more. Since Fe is a substance to be removed and its content is low, the upper limit of its content can be 80 wt% or less. However, if the Fe content is too low, the necessity of applying the process of the present invention is reduced, so that Fe in the raw material can be set to 50 wt% or more, preferably 60 wt% or more. The upper limit of the Ni content can be determined from the lower limit of the Fe content (Ni content upper limit (wt%) = 100 - Fe content lower limit (wt%)). Impurities may be contained as the remaining components, and when Ni ore such as limonite is used as the raw material ore for producing FeNi, these impurities may be impurities derived from ore.

In one embodiment of the present invention, the raw material FeNi may be in the form of granules or powder to activate the reaction through the surface, wherein the average particle size of the powder may be less than 2 mm.

The FeNi raw material can be produced by any method as long as the above-described conditions are satisfied. However, the FeNi raw material can be manufactured by the method shown in FIG. 2, which is one embodiment of the present invention. Briefly, the step of drying / firing the Rimnite light, which is the Ni raw material light, Hydrogen reduction; Leaching hydrogen reduced reduced light with an acid such as hydrochloric acid; And adding Fe powder or the like to the leaching solution to precipitate Ni on the Fe powder to obtain an FeNi powder. As such a method, Korean Patent Registration No. 10-1353721 can be referred to.

The above-mentioned primary de-ironing reaction can be performed in a state where oxygen-containing gas is injected into the process water. The role of oxygen contained in the oxygen-containing gas is oxidized to Fe ^{2 +} eluted from FeNi material as Fe ^3+, and the oxidized Fe ^{3 +} is precipitated as an oxide or hydroxide form.

The method of injecting the oxygen-containing gas is not particularly limited, and in one embodiment of the present invention, the oxygen-containing gas is injected into the process water through the injection means such as a tube or a pipe so that the stirring of the process solution and the injection of oxygen occur simultaneously can do.

The rate of introduction of the oxygen-containing gas may be such that the feed rate per minute is 1 to 3.6 times the volume of the aqueous ammonium chloride solution based on the amount of oxygen in the gas. That is, in order to obtain a sufficient reaction effect, the injection rate per minute of oxygen needs to be at least one times the volume of the aqueous ammonium chloride solution. However, if the amount of oxygen is excessive, it is difficult to expect a further increase in the effect, so that the upper limit can be set at 3.6 times. According to one embodiment of the present invention, the rate of oxygen injection per minute may be limited to 1.5 to 3 times. Since the amount is based on the amount of oxygen contained in the oxygen-containing gas, the amount of air injected per minute when using air (including 20% oxygen), which is an example of the oxygen-containing gas, is 5-18 times the volume of the aqueous ammonium chloride solution have.

In one embodiment of the present invention, the content of oxygen contained in the oxygen-containing gas may be 15% or more of the volume of the total gas in order to obtain a sufficient reaction effect. Since the oxygen content can be added up to 100%, the upper limit of the oxygen content is not particularly limited.

In addition, the temperature of the process water in the primary de-ironing process can be controlled in the range of 60 to 90 ° C. That is, in order to obtain sufficient reaction efficiency, it is necessary to control the temperature of the aqueous solution to 60 ° C or higher. Also, it is possible to prevent the aqueous solution from evaporating at a high temperature, and in consideration of energy efficiency, the temperature of the process water can be controlled to 90 ° C or less. According to one embodiment, the temperature of the process water may be controlled at 70 to 85 ° C, and in another embodiment may be controlled at 80 ° C.

In order to remove a sufficient amount of Fe, a first decarburization reaction process can be performed for 6 hours or more. 18 hours, it is possible to obtain a sufficient effect. In order to reduce the processing cost, the upper limit of the first decarburization reaction time can be set to 18 hours. In one embodiment of the present invention, the primary decarburization reaction time can be set to 7 to 15 hours.

At this time, in order to induce an effective reaction, it is necessary to maintain the pH of the process water at 2.5 to 5.5. To this end, neutralizing agents or acids may be added to the process water. Examples of the neutralizing agent that can be used in the present invention include sulfuric acid, hydrochloric acid, nitric acid, hydrofluoric acid, and the like, and examples of the neutralizing agent include calcium oxide, calcium hydroxide, calcium carbonate, magnesium carbonate, dolomite, caustic soda, have.

The Fe ^{2 +} eluted by the above-mentioned process is oxidized to Fe ^{3 +} , and as a result, an oxide or hydroxide of Fe ^{3 +} is formed and precipitated. Therefore, Ni mainly remains in the charged FeNi raw material.

And adding an acid to the process water. The acid addition is a process for eluting Ni remaining in the raw material. Since the eluted and precipitated Fe is a trivalent oxide and does not dissolve well in acid, the amount of Fe to be redissolved is insignificant even when an acid is added. Therefore, a large amount of Ni ions and a small amount of Fe ^& lt ^{; 2 + &} gt ^; ions are included in the process water after the addition of the acid. One example of an acid for eluting Ni is hydrochloric acid. The amount of the acid added is determined by the content of Ni remaining in the raw material. That is, the acid may be added to such an extent as to substantially completely dissolve the Ni contained in the raw material. Here, the substantially dissolving substantially means that at least 80% of the total mass of Ni contained in the initial raw material (FeNi) It means that at least 90% in embodiments, and at least 95% in one preferred embodiment, have been dissolved in the process water. In one embodiment of the present invention, the pH of the process water after Ni is dissolved by the acid addition may have a value of 1.5 to 4.5.

And a second decarburization reaction step of adding an oxidizing agent to the process water in order to precipitate and remove a small amount of Fe ^{2 +} ions contained in the process water to an oxide or hydroxide of Fe ^{3 +} ions. In one embodiment of the present invention, hydrogen peroxide or sodium hypochlorite may be used as the oxidizing agent. At this time can be made sufficient reaction efficiency, the addition of Fe2 ⁺ ion amount of the oxidizing agent to be added in order to reduce costs at a rate of 100 to 250% of stoichiometric for the oxidation of the Fe ^{3 +} ion, one implementation example of the invention , The amount of the oxidizing agent may be in the range of 120 to 170% based on the chemical equivalent. Since the pH is lowered in the process of the de-ironing reaction and the reaction efficiency may be decreased, a process of adding a neutralizing agent to the process water may be further included. The neutralizing agent addition process may be performed before or during the reaction. According to one embodiment of the present invention, quicklime or caustic soda can be used as the neutralizing agent.

By such a process, the pH of the process water in the second decarburization reaction process can be maintained at a value of 1.5 to 4.5, and Fe ^{2 +} is precipitated as Fe ^{3 +} .

After the above-mentioned process, the precipitated solid phase is separated from the process water. As a result, a Ni concentrated liquid containing Ni ions can be obtained. Any method known so far can be used for separating the concentrated liquid from the solid phase and various methods such as filtration and centrifugation can be used.

Thus, the method for producing the Ni concentrate of the present invention comprises the steps of: preparing an FeNi raw material; Adding the FeNi raw material to an ammonium chloride aqueous solution to prepare a process water; Injecting an oxygen-containing gas into the process water; Adding an acid to the process water to elute Ni; Adding an oxidizing agent to the process water; And separating the solid phase from the process water to obtain a Ni concentrate.

Thereafter, Ni in the Ni concentrate can be recovered in the form of hydroxide, sulfate, chloride or Ni metal by conventional methods known so far.

Claims (10)

Preparing a FeNi raw material;
Adding the FeNi raw material to an ammonium chloride aqueous solution to prepare a process water;
Injecting an oxygen-containing gas into the process water;
Adding an acid to the process water to elute Ni;
Adding an oxidizing agent to the process water to oxidize Fe ²⁺ ions selected from hydrogen peroxide and sodium hypochlorite to Fe ³⁺ ions;
And separating the solid phase from the process water to obtain a Ni concentrate.
The method according to claim 1,
Wherein the ammonium chloride in the ammonium chloride aqueous solution is contained at a concentration of 0.5 to 4.0 wt%.
The method according to claim 1,
Wherein the mass of the ammonium chloride aqueous solution is 2 to 8 times the mass of the FeNi raw material.
The method according to claim 1,
Wherein the temperature of the process water in the step of injecting the oxygen-containing gas into the process water is in the range of 60 to 90 占 폚.
The method of claim 1, wherein injecting the oxygen-containing gas into the process water is performed for 6 to 18 hours.
The method according to claim 1,
Wherein the pH of the process water in the step of injecting oxygen-containing gas into the process water is maintained at 2.5 to 5.5.
The method according to claim 1,
Wherein the injection rate of the oxygen-containing gas in the step of injecting the oxygen-containing gas into the process water is 1 to 3.6 times the volume of the ammonium chloride aqueous solution per minute, based on the amount of oxygen in the gas.
The method according to claim 1,
Wherein the Ni content in the FeNi raw material is 20 wt% or more, and the Fe content is 80 wt% or less.
The method according to claim 1,
Wherein the pH of the process water after the step of eluting Ni by adding an acid to the process water is 1.5 to 4.5.
delete

Images