JP7318539B2 - Method for producing nickel chloride solution and method for producing nickel sulfide - Google Patents

Description

The present invention relates to a method for producing a nickel chloride solution used in hydrometallurgy of nickel oxide ore.

In the field of nickel hydrometallurgy using nickel oxide ore as a raw material, recovery of valuable metals from low nickel grade ores by acid leaching (HPAL method) using high temperature and high pressure has been put into practical use. Valuable metals such as nickel and cobalt leached from nickel oxide ores by the HPAL method can be recovered by adding a sulfurizing agent such as hydrogen sulfide gas to a nickel-containing solution in a sulfurization reaction vessel to cause a sulfurization reaction. A method of recovering nickel sulfide (hereinafter also referred to as MS product) is generally practiced (see Patent Document 1, for example).

On the other hand, nickel sulfide (MS product) undergoes a hydrometallurgical process consisting of a cementation process and a chlorine leaching process, for example, as described in Patent Document 2, and is electrowinning to produce electricity. Refining methods for obtaining nickel and electrolytic cobalt have been put into practical use.

At that time, as shown in Patent Documents 3 and 4, for example, in order to adjust the powder characteristics in advance, nickel sulfide (MS product) is pulverized with a pulverizer, and the pulverized product is leached with chlorine. Treatment is common. Patent Document 5 discloses a pulverizing device for pulverizing nickel sulfide (MS product).

JP 2005-350766 A Japanese Patent Application Laid-Open No. 2003-082421 JP 2008-156713 A JP 2019-81920 A JP 2018-58052 A

In the sulfidation reactor used in the HPAL process, nickel-containing sulfide scale may be deposited on the inner wall of the vessel, stirring blades, and the like. Since this scale reduces the volume of the sulfurization reactor, it is removed from the sulfurization reactor during the manufacture of the MS product. This scale contains nickel sulfide, and it is preferable to recover it as nickel sulfide in the same manner as the MS product rather than treating it as a waste product from the viewpoint of improving the yield.

However, the nickel sulfide scale formed in such a sulfidation reaction vessel has a higher hardness than the nickel sulfide MS product, and the nickel sulfide scale is used as it is for crushing the MS product. If the nickel sulfide scale is pulverized by , it may wear out the pulverizer, so it was difficult to pulverize the nickel sulfide scale and use it effectively.

The present invention has been proposed in view of such circumstances, and provides a method capable of effectively utilizing the nickel sulfide scale formed in the sulfurization reaction vessel used for the production of nickel sulfide. With the goal.

The present inventors have found that the nickel sulfide scale formed in the sulfurization reaction vessel can be used without waste by mixing it with the MS product. The inventors have found that the scale of nickel sulfide can be effectively utilized by pulverizing and mixing at a predetermined ratio, and have completed the present invention.

(1) The first aspect of the present invention is a method of producing a nickel chloride solution by using nickel sulfide as a raw material and leaching the nickel sulfide with chlorine, wherein nickel is A pretreatment step of preparing the nickel sulfide as a raw material, a pulverizing step of pulverizing the prepared nickel sulfide, and pulverizing the nickel sulfide and a leaching step of subjecting the substance to chlorine leaching treatment, wherein the pretreatment step includes a step of recovering nickel sulfide scale formed in the sulfidation reaction vessel, and pulverizing the scale to a predetermined particle size and a step of mixing the nickel sulfide obtained by the sulfidation reaction with the pulverized scale in a predetermined ratio to obtain a nickel sulfide mixture, wherein the pulverized The step is a method of producing a nickel chloride solution by pulverizing the nickel sulfide mixture obtained through the pretreatment step.

(2) A second aspect of the present invention is the method according to the first aspect, wherein in the pretreatment step, the pulverized scale material having a particle size of 2.36 mm or less is obtained.

(3) In the third aspect of the present invention, in the first or second aspect, in the pretreatment step, 0.5 parts by mass or more and 2.0 parts by mass with respect to 100 parts by mass of nickel sulfide obtained by the sulfurization reaction It is a method of mixing the pulverized scale in a proportion of parts by mass or less.

(4) A fourth aspect of the present invention is a method according to any one of the first to third aspects, wherein in the pretreatment step, the scale is dry-pulverized to obtain the pulverized scale material.

(5) A fifth aspect of the present invention is a method according to the fourth aspect, wherein in the pretreatment step, the scale is dry pulverized by a rod mill.

(6) A sixth aspect of the present invention is a method for producing nickel sulfide obtained by subjecting a solution containing nickel to a sulfurization reaction in a sulfurization reaction vessel, wherein the nickel sulfide scale formed in the sulfurization reaction vessel a step of pulverizing the scale to obtain a pulverized scale material having a predetermined particle size or less; mixing the pulverized scale material with the nickel sulfide obtained by the sulfurization reaction in a predetermined ratio to obtain nickel and obtaining a mixture of sulfides.

According to the present invention, nickel sulfide scale formed in a sulfurization reaction vessel used for producing nickel sulfide can be effectively utilized.

It is a figure which shows an example of the flow of the manufacturing method of nickel chloride solution. FIG. 1 is a flow diagram of a hydrometallurgical process of nickel oxide ore, showing the flow of producing nickel sulfide from nickel oxide ore.

Specific embodiments of the present invention (hereinafter referred to as "present embodiments") will be described in detail below. In addition, the present invention is not limited to the following embodiments, and various modifications are possible without changing the gist of the present invention.

<1. Method for producing nickel chloride>
In the method for producing a nickel chloride solution according to the present embodiment, a nickel sulfide is used as a raw material, and the nickel sulfide is leached with chlorine to produce a nickel chloride solution. Nickel sulfide used as a raw material is obtained by subjecting a solution containing nickel to a sulfurization reaction in a sulfurization reactor.

FIG. 1 is a process drawing showing an example of the flow of the method for producing a nickel chloride solution according to the present embodiment. As shown in FIG. 1, the method for producing a nickel chloride solution includes a pretreatment step S1 for preparing nickel sulfide as a raw material, a pulverizing step S2 for pulverizing the prepared nickel sulfide, and a pulverized nickel sulfide. and a leaching step S3 in which chlorine leaching treatment is performed on the

In this manufacturing method, the nickel sulfide to be subjected to the chlorine leaching treatment in the leaching step S3 is subjected to crushing treatment using a crusher prior to the treatment (crushing step S2). By obtaining nickel sulfide with a predetermined particle size through the pulverization process in the pulverization step S2, the efficiency of the chlorine leaching reaction can be enhanced, and the nickel leaching rate can be improved.

Here, in the method for producing a nickel chloride solution according to the present embodiment, as the nickel sulfide used as a raw material, nickel formed in the reaction vessel when producing the nickel sulfide (MS product) in the sulfidation reaction vessel It is characterized by using a mixture of collected sulfide scales. Since the scale formed in the sulfurization reaction vessel is nickel sulfide, by collecting the scale and mixing it with the MS product, the scale can be effectively used, and the nickel sulfide (MS product) can be collected. It is also preferable in that the rate can be improved.

However, the scale formed in the sulfurization reaction vessel has a higher hardness than the MS product normally used in the method for producing the nickel chloride solution. In pulverization using a pulverizer, it becomes a factor that causes wear of the pulverizer, and it may not be used effectively.

Therefore, in the method for producing a nickel chloride solution according to the present embodiment, the step of preparing nickel sulfide ( It is characterized by having a pretreatment step S1).

Specifically, the pretreatment step S1 includes a step (scale recovery step) S11 of recovering nickel sulfide scale formed in the sulfidation reaction vessel, and a pulverized scale material having a predetermined particle size or less by pulverizing the recovered scale. and a step of mixing the nickel sulfide (MS product) obtained by the sulfurization reaction with the pulverized scale in a predetermined ratio to obtain a nickel sulfide mixture (mixing step). and S13. Then, the nickel sulfide mixture obtained through the pretreatment step S1 is pulverized in the pulverization step S2.

According to such a production method, it is possible to effectively utilize the nickel sulfide scale formed in the sulfurization reaction vessel. Also, when using the scale, it is pulverized into a pulverized scale material with a predetermined particle size or less and mixed with MS products at a predetermined ratio. Pulverization can be efficiently performed without causing wear to the material. In this way, nickel sulfide scale can be effectively utilized.

<2. Each step of the method for producing nickel chloride>
Hereinafter, each step of the method for producing the nickel chloride solution will be described in more detail, but prior to the explanation, the process for producing nickel sulfide as a raw material will be described.

<2-1. About the manufacturing process of nickel sulfide>
As described above, the nickel sulfide used as a raw material is obtained by subjecting a solution containing nickel to a sulfurization reaction in a sulfurization reactor. Specifically, a nickel sulfide (MS product) obtained through a sulfurization step in a hydrometallurgical process of nickel oxide ore can be used. The outline of the hydrometallurgical process by the HPAL method is explained below, and the production flow of nickel sulfide is shown.

FIG. 2 is a diagram showing an example of a hydrometallurgical process flow of nickel oxide ore. As shown in FIG. 2, the hydrometallurgical process includes a leaching step S51 in which sulfuric acid is added to a slurry of nickel oxide ore and subjected to leaching treatment under high temperature and high pressure, and a leaching residue is separated from the resulting leaching slurry to produce nickel. A solid-liquid separation step S52 for obtaining a leachate containing and a sulfurization step S54 of adding a sulfurizing agent to the neutralization final solution used to cause a sulfurization reaction to produce a nickel sulfide (MS product). Nickel sulfide is obtained through such a hydrometallurgical process. Incidentally, the nickel sulfide obtained through the hydrometallurgical process is a mixture of nickel sulfide and cobalt sulfide (nickel-cobalt mixed sulfide), but the explanation is continued as "nickel sulfide".

Here, in the sulfurization treatment in the sulfurization step S54, nickel-containing sulfide scale may be deposited on the inner wall of the vessel, the stirring blades, and the like in the sulfurization reaction vessel. In the method for producing a nickel chloride solution according to the present embodiment, the scale of nickel sulfide formed in such a sulfidation reaction vessel is subjected to a specific pretreatment (pretreatment step S1 to be described later) to obtain an MS product. I try to make effective use of it together with Details will be described later.

<2-2. About each step of the method for producing nickel chloride>
As described above, the method for producing a nickel chloride solution according to the present embodiment includes a pretreatment step S1 for preparing nickel sulfide as a raw material, a pulverizing step S2 for pulverizing the nickel sulfide after preparation, and a nickel sulfide and a leaching step S3 in which the pulverized material is subjected to a chlorine leaching treatment.

(1) Pretreatment Step In the pretreatment step S1, nickel sulfide as a raw material is prepared. Specifically, the pretreatment step S1 includes a step (scale recovery step) S11 of recovering nickel sulfide scale formed in the sulfidation reaction vessel, and pulverizing the scale to obtain pulverized scale having a predetermined particle size or less. a step (scale pulverized material producing step) S12, and a step (mixing step) S13 of obtaining a nickel sulfide mixture by mixing the nickel sulfide (MS product) obtained by the sulfurization reaction with the pulverized scale material in a predetermined ratio. , have

The mixture of nickel sulfides obtained through the treatment in the pretreatment step S1 becomes nickel sulfides to be pulverized in the pulverization step S2.

By performing the treatment in the pretreatment step S1, the nickel sulfide scale formed in the sulfurization reaction vessel can be effectively utilized. Also, when using the scale, it is pulverized into a pulverized scale material with a predetermined particle size or less and mixed with MS products at a predetermined ratio. Pulverization can be efficiently performed without causing wear to the material. That is, the nickel sulfide scale can be effectively utilized.

(1-1) Scale collection step S11
In the scale recovery step S11, nickel sulfide scale formed in the sulfurization reactor is recovered.

The method for recovering the scale of nickel sulfide is not particularly limited, and is a method of scraping the scale deposited in the sulfidation reaction vessel using a jig made of metal (including alloy), ceramic, diamond, or the like. good.

(1-2) Scale pulverized product generation step S12
In the pulverized scale production step S12, the collected scale is pulverized to obtain pulverized scale having a predetermined particle size or less.

(Process of pulverizing)
The method for pulverizing scale is preferably dry pulverization in which scale is pulverized in air or inert gas. In this step, it suffices to obtain a scale pulverized product having a particle size that can suppress wear on the pulverizer in the pulverization process in the pulverization step S2. you don't have to. In addition, dry pulverization requires smaller equipment than wet pulverization, and unlike wet pulverization, there is no need to filter pulverized scales, which is favorable in terms of cost.

When dry-grinding scale, the dry-grinding machine is not particularly limited, but includes jaw crushers, gyratory crushers, cone crushers, roll crushers, impact crushers, hammer crushers, rod mills, ball mills, vibrating rod mills, and vibrating ball mills. , disk type mills, jet mills and cyclone mills are preferably used, most preferably rod mills. The rod mill is filled with rod-shaped grinding media, and the impact is transmitted preferentially to large-sized particles, and relatively not to small-sized particles, so that the entire sulfide scale is evenly ground. becomes possible. Therefore, it becomes difficult for pulverized scale particles exceeding a predetermined particle size to remain, and the risk of wear and tear of the pulverizer can be more effectively suppressed.

When the scale is dry pulverized with a rod mill, the rotation speed of the rod mill is not particularly limited, but is preferably 20 rpm or more and 40 rpm or less. Moreover, it is preferable that the treatment time for dry pulverization is 1 hour or more and 3 hours or less.

(Step of sieving)
Next, the pulverized scale material obtained by pulverizing the scale is separated into an over-sieve portion and an under-sieve portion using a sieve having a predetermined opening size, and the pulverized scale portion having a predetermined particle size or less under the sieve is separated. obtain. As a result, it is possible to easily separate the pulverized scale material exceeding a predetermined particle size from the pulverized scale material obtained, and to effectively suppress the wear and tear of the pulverizer in the pulverizing process in the pulverizing step S2 described later. can.

Although the sieve is not particularly limited, it is preferable to use a vibrating sieve.

The mesh size of the sieve is preferably 1.70 mm or more and 2.36 mm or less, more preferably 1.80 mm or more and 2.20 mm or less. When the size of the sieve mesh is 1.70 mm or more, it is possible to shorten the time required for this step of obtaining a pulverized scale material having a predetermined particle size or less. Moreover, since the size of the sieve mesh is 2.36 mm or less, it is possible to more effectively suppress wear and tear of the crusher in the crushing process in the crushing step S2, which will be described later.

(1-3) Mixing Step In the mixing step S13, pulverized scale having a predetermined particle size or less obtained in the pulverized scale generation step S12 is added to the nickel sulfide (MS product) obtained by the sulfurization reaction in the sulfurization step S4. Mix in the prescribed proportions.

In the mixing step S13, it is preferable to mix 0.5 parts by mass or more and 2.0 parts by mass or less of pulverized scale with 100 parts by mass of the nickel sulfide (MS product) obtained by the sulfurization reaction. . By mixing the pulverized scale material at a rate of 0.5 parts by mass or more, the amount of scale relative to the amount of the nickel sulfide mixture increases, and the amount of nickel recovered from the scale increases. Further, by mixing the pulverized scale material at a ratio of 2.0 parts by mass or less, it is possible to more effectively suppress wear and tear of the pulverizer in the pulverization process in the pulverization step S2 described later.

The method of mixing the pulverized scale with nickel sulfide, which is an MS product obtained by the sulfurization reaction, is not particularly limited, and the pulverized scale is directly thrown into a container containing nickel sulfide so that the pulverized scale has a predetermined ratio. and mixing method. Such a method is simple and does not require new equipment investment, and is therefore favorable in terms of cost.

(2) Pulverization Step In the pulverization step S2, the nickel sulfide prepared in the pretreatment step S1, that is, a mixture of the nickel sulfide (MS product) and pulverized scale material having a predetermined particle size or less is pulverized.

The crushing treatment in the crushing step S2 is performed prior to the chlorine leaching treatment in the leaching step S3, which is the next step. The efficiency of the chlorine leaching reaction can be increased to improve the nickel leaching rate.

In the pretreatment step S1 described above, the scale pulverized material having a predetermined particle size or less is pulverized and mixed with the MS product at a predetermined ratio, so that the pulverizer is not damaged in the pulverization step S2. Pulverization treatment can be performed efficiently. As the pulverizer used here, for example, a pulverizer (wet type vertical pulverizer) as disclosed in Patent Document 5 (Japanese Patent Application Laid-Open No. 2018-58052) may be used.

(3) Leaching Step In the leaching step S3, the pulverized nickel sulfide obtained in the pulverizing step S2 is subjected to a chlorine leaching treatment. Specifically, by blowing chlorine gas into a slurry of pulverized nickel sulfide, metals such as nickel contained in the sulfide are leached into the solution. Thereby, a nickel chloride solution can be obtained.

<3. Method for producing nickel sulfide>
In the above description, the method for producing a nickel chloride solution was taken as an example to explain in detail the method for pretreating nickel sulfide as a raw material. Other production methods can be suitably used as long as the nickel sulfide obtained is used as a raw material and the nickel sulfide is pulverized.

That is, the present invention can also be defined as a method for producing nickel sulfide obtained by subjecting a solution containing nickel to a sulfurization reaction in a sulfurization reactor. Specifically, this method for producing nickel sulfide includes a step of recovering nickel sulfide scale formed in the sulfurization reaction vessel (S11), and a step of pulverizing the scale to obtain pulverized scale having a predetermined particle size or less. (S12), and a step (S13) of obtaining a mixture of nickel sulfides by mixing the nickel sulfides obtained by the sulfurization reaction with pulverized scale in a predetermined ratio.

Since the details of each step are the same as those described above, descriptions thereof are omitted here.

According to such a method for producing nickel sulfide, nickel sulfide (MS product) obtained by the sulfurization reaction and scale formed in the sulfurization reaction vessel in the sulfurization reaction can be effectively used. Also, when using the scale, it is pulverized into a scale pulverized product with a predetermined particle size or less and mixed with nickel sulfide (MS product) at a predetermined ratio. Efficient pulverization can be performed without causing wear and tear. That is, the nickel sulfide scale can be effectively utilized.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples of the present invention. In addition, the present invention is not limited at all by the following examples.

(Example 1)
A final neutralization solution (solution containing nickel) is continuously supplied to a sulfurization reaction vessel, and a sulfurization agent (hydrogen sulfide gas) is added to the nickel-containing solution in the sulfurization reaction vessel to cause a sulfurization reaction. and passed through the MS product of nickel sulfide (nickel-cobalt mixed sulfide) (sulfurization process).

Also, the sulfide scale in the sulfurization reaction vessel used in the sulfurization step was recovered (scale recovery step).

Then, about 100 kg of the recovered sulfide scale is put into a pulverizer (manufactured by Furukawa Sanki Systems Co., model number: B-912 horizontal rod mill (inner diameter 900 mm, length 1200 mm), and the rotation speed of the rod mill is 30 rpm for 2 hours. Dry pulverization was performed (process of pulverizing).

After dry pulverization, a sieve with a sieve mesh size of 2 mm was used to obtain a pulverized scale material having a particle size of 2 mm or less (step of sieving). The pulverized scale material having a particle size of more than 2 mm was put into the pulverizer again and subjected to dry pulverization.

Then, with respect to 2000 kg of MS product of nickel sulfide obtained by the above sulfurization reaction, 10 to 30 kg of scale pulverized product (0.5 to 1.5 parts by mass with respect to 100 parts by mass of MS product of nickel sulfide mixture) ratio) were added and mixed to obtain a mixture of nickel sulfides (mixing step).

Using the resulting mixture of nickel sulfides as a raw material, a nickel chloride solution was produced through a pulverization step and a leaching step. In the pulverization step, wet pulverization was performed using a wet vertical pulverizer (Tower Mill (registered trademark) manufactured by Eirich Japan Co., Ltd. (ETM-500MS)). A nickel chloride solution was prepared by chlorine leaching the nickel sulfide obtained from the grinding process. Production of such a nickel chloride solution was operated for half a year, and after half a year of operation, the state of wear inside the crusher was checked.

(Reference example 1)
Nickel sulfide (MS product) not mixed with pulverized scale was used as a raw material, and a nickel chloride solution was produced through a pulverization process and a leaching process. In addition, the production of the nickel chloride solution described above was operated for half a year, and after the operation was carried out for half a year, the state of wear and tear inside the wet vertical pulverizer was checked.

From Table 1, in Example 1 in which the nickel sulfide mixture obtained through the pretreatment step was used as the raw material and the nickel chloride solution was produced through the pulverization step and the leaching step, pulverized scale was mixed. As in Reference Example 1, in which nickel sulfide (MS product) was used as a raw material, there was no wear inside the crusher.

From the above results, even if a mixture of pulverized scales having a predetermined particle size or less and mixed with an MS product at a predetermined ratio is used as a raw material, it is possible to carry out the pulverization process without causing damage to the pulverizer during the pulverization process. was made. Therefore, it can be seen that the method of the present invention can effectively utilize nickel sulfide scale.

Claims (6)

A method for producing a nickel chloride solution by using nickel sulfide as a raw material and leaching the nickel sulfide with chlorine, comprising:
As the nickel sulfide, using one obtained by subjecting a nickel-containing solution to a sulfurization reaction in a sulfurization reaction vessel,
a pretreatment step of preparing the nickel sulfide as a raw material;
a pulverizing step of pulverizing the prepared nickel sulfide;
a leaching step of performing a chlorine leaching treatment on the pulverized nickel sulfide;
including
The pretreatment step includes
recovering nickel sulfide scale formed in the sulfidation reaction vessel;
pulverizing the scale to obtain a pulverized scale material having a predetermined particle size or less;
a step of mixing the pulverized scale material in a predetermined proportion with the nickel sulfide obtained by the sulfurization reaction to obtain a nickel sulfide mixture;
The method for producing a nickel chloride solution, wherein, in the pulverization step, the mixture of nickel sulfides obtained through the pretreatment step is pulverized. 2. The method according to claim 1, wherein in the pretreatment step, the pulverized scale material having a particle size of 2.36 mm or less is obtained. 3. In the pretreatment step, the pulverized scale is mixed at a ratio of 0.5 parts by mass or more and 2.0 parts by mass or less with respect to 100 parts by mass of the nickel sulfide obtained by the sulfurization reaction. The method described in . In the pretreatment step,
4. The method according to any one of claims 1 to 3, wherein the scale pulverized product is obtained by dry pulverizing the scale. In the pretreatment step,
5. The method of claim 4, wherein the scale is dry ground with a rod mill. A method for producing a nickel sulfide obtained by subjecting a solution containing nickel to a sulfurization reaction in a sulfurization reaction vessel,
recovering nickel sulfide scale formed in the sulfidation reaction vessel;
pulverizing the scale to obtain a pulverized scale material having a predetermined particle size or less;
A method for producing nickel sulfide, comprising the step of mixing the pulverized scale material in a predetermined ratio with the nickel sulfide obtained by the sulfurization reaction to obtain a nickel sulfide mixture.

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