KR101514837B1 - The preparation method of sulfides using oxide flux from deep ocean manganese nodules - Google Patents

Abstract

The present invention relates to a method for manufacturing sulfides from deep-ocean manganese nodules using oxide flux and, more particularly, to a method for manufacturing oxides from deep-ocean manganese nodules using oxide flux, the manufacturing method comprising the steps of: manufacturing alloy by crushing, drying, and smelting-reducing deep-ocean manganese nodules; and manufacturing sulfides by adding waste gypsum, a reducing agent and oxide flux to the manufactured alloy and performing pyrometallurgy.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preparing sulfides from deep sea manganese nodules using an oxide flux,

The present invention relates to a method for producing an alloy obtained from deep sea manganese nodules as a sulfide using an oxide flux.

Deep - sea manganese nodule is a marine mineral resource that exists in the deep sea basins such as the Pacific Ocean and the Indian Ocean and contains a large amount of copper, nickel, cobalt and manganese. In the development of deep sea manganese nodule, smelting technology is a process of extracting and recovering valuable metals from manganese nodules, and it is an important part that the facility investment cost accounts for more than 50% of the total and the operating cost account for more than 60% of the total. The smelting method of manganese nodule can be classified into reduction melting-wet leaching method, rosin-leaching method, and direct leaching method. Among these, dry and wet smelting method which is easy to treat and recycle smelting residue, Is a promising process for manganese nodules.

The process of reducing manganese nodule reduction melt-leaching method is divided into two steps. First, in step 1, manganese, aluminum, silica, alkali metals and some iron in manganese nodules are slagged, and nickel, copper, cobalt and iron are separated into metallic alloy phases using a reduction melting method. Since the alloy phase thus obtained is poorly soluble and is not easy to break down, sulfur is added to form a sulfide (matte phase). In step 2, the sulfide thus obtained is dissolved in an inorganic acid, and is separated into individual metals by a solvent extraction method and the like, and finally a metal or metal compound product is obtained by an electrolytic extraction method or the like.

As described above, the alloy phase produced by the reduction smelting process is made from sulfide by adding sulfur. However, when the crude metal is leached from the sulfide thus produced, a large amount of acid solution is used and the leaching efficiency of the valuable metal is not high, Since the efficiency is low and the cost is high, there is a need for a process capable of improving this.

As a prior art related to this, there is a "leaching method of a valuable metal on a mat from deep sea manganese nodule" disclosed in Korean Patent Laid-Open Publication No. 10-2005-0008061 (published on Jan. 21, 2005).

Accordingly, the present invention provides a method for producing a sulfide from deep sea manganese nodules using an oxide flux which can easily break the alloy, reduce acid consumption, improve the leaching efficiency of valuable metals, and require less time for dry smelting in a subsequent process .

The problems to be solved by the present invention are not limited to the above-mentioned problem (s), and another problem (s) not mentioned can be understood by those skilled in the art from the following description.

In order to solve the above-mentioned problems, the present invention provides a method for producing an alloy, comprising: crushing and drying a deep sea manganese nodule; And

The present invention also provides a method for producing a sulfide from deep sea manganese nodules using an oxide flux, comprising the steps of: adding a waste stone, a reducing agent and an oxide flux to the alloy; and dry-smelting the sulfide to produce a sulfide.

At this time, the melt-reduction is performed at 1300 to 1500 ° C.

Wherein the alloy comprises copper, nickel, cobalt and iron, wherein the alloy comprises 33.0 to 33.2 wt% copper, 43.0 to 43.5 wt% nickel, 5.0 to 5.6 wt% cobalt, 17.0 to 17.5 wt% iron, and other impurities .

The waste scum is added in an amount of 150 to 270 g based on 100 g of the alloy.

The reducing agent may be carbon, and the reducing agent may be added so that the weight ratio of the waste sludge: reducing agent is 17: 5-9.

The oxide flux may be at least one selected from the group consisting of Al ₂ O ₃ and Fe _t O (ratios of 0 <t≤1).

The oxide flux is added in an amount of 5 to 15 parts by weight based on the total weight of the waste stone.

The dry smelting is performed at 1360 to 1500 ° C, and is performed while supplying Ar, CO, CO ₂ and SO ₂ , and is performed for 2 hours to 10 minutes to 2 hours and 30 minutes.

According to the present invention, it is possible to prevent environmental pollution and reduce the process cost by using waste scrap that causes environmental pollution by freezing, moisture absorption, leachate and scattering by wind, as a substitute for sulfur.

In addition, it is possible to produce a sulfide having a sulfur content of 20 wt% or more by using a reducing agent for decomposing waste stones by using waste scraps that are discarded as waste resources, and further by adding an oxide flux, It is possible to produce a sulfide of a matte phase having a concentration of 20 wt% or more.

In addition, since the sulfide contains 20 wt% or more of sulfur, the alloy can be easily broken in the subsequent process, and H ₂ SO ₄ and the like are naturally generated by the sulfur contained in the sulfide, so that the amount of sulfuric acid used can be reduced, The contamination can be minimized, and the leaching efficiency of the metal can be improved to reduce the process cost.

1 is a flowchart showing a method for producing a sulfide from deep sea manganese nodules using an oxide flux according to the present invention.
FIG. 2 is a schematic diagram showing a device used for dry smelting in the process for producing sulfides from deep sea manganese nodules using the oxide flux according to the present invention.
FIG. 3 is a graph showing changes in sulfur content in sulfides with time in the case where an oxide flux is not used in the method for producing sulfides from deep sea manganese nodules.
FIG. 4 is a graph showing changes in sulfur content in sulfides according to the amount of oxide flux added in the process for producing sulfides from deep sea manganese nodules using the oxide flux according to the present invention.
FIG. 5 is a graph showing changes in sulfur content in sulphides according to the time of dry smelting in the process for producing sulphides from deep sea manganese nodules using the oxide flux according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving it will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings.

However, the present invention is not limited to the embodiments described below, but may be implemented in various other forms, and these embodiments are not intended to be exhaustive or to limit the invention to the precise form disclosed, Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

The present invention relates to a process for producing an alloy by crushing and drying a deep sea manganese nodule, followed by melting and reducing it; And

The present invention also provides a method for producing a sulfide from deep sea manganese nodules using an oxide flux, comprising the steps of: adding a waste stone, a reducing agent and an oxide flux to the alloy; and dry-smelting the sulfide to produce a sulfide.

The method for producing sulfides from deep sea manganese nodules using oxide fluxes according to the present invention is to prevent environmental pollution by using waste rock as a substitute for sulfur which causes environmental pollution due to freezing, moisture absorption, leachate and scattering by wind, The cost can be reduced.

In addition, it is possible to produce a sulfide having a sulfur content of 20 wt% or more by using a reducing agent for decomposing waste stones by using waste scraps that are discarded as waste resources, and further by adding an oxide flux, It is possible to produce a mat-sulphide alloy having a weight ratio of 20 wt% or more.

In addition, since the sulfide contains 20 wt% or more of sulfur, the alloy can be easily broken in the subsequent process, and H ₂ SO ₄ and the like are naturally generated by the sulfur contained in the sulfide, so that the amount of sulfuric acid used can be reduced, The contamination can be minimized, and the leaching efficiency of the metal can be improved to reduce the process cost.

1 is a flowchart showing a method for producing a sulfide from deep sea manganese nodules using an oxide flux according to the present invention. Hereinafter, the present invention will be described in detail with reference to Fig.

The method for producing a sulfide from deep sea manganese nodules using the oxide flux according to the present invention includes a step (S10) of producing an alloy by crushing and drying the deep sea manganese nodule, followed by melting and reducing.

Deep - sea manganese nodule is a marine mineral resource that exists in the deep sea basins such as the Pacific Ocean and the Indian Ocean and contains a large amount of copper, nickel, cobalt and manganese. In order to extract, separate and recover valuable metals from these deep sea manganese nodules, the manganese nodule should be formed in a matte form and the sulfur content should be 20 wt% or more for the efficiency of the recovery process of Ni and Co.

The method for producing sulfides from deep sea manganese nodules using the oxide flux according to the present invention is characterized in that manganese, aluminum, silica, alkali metal and some iron in the manganese nodule are slagged in manganese nodules by crushing and drying the deep- Copper, nickel, cobalt and iron can be separated into metal alloy phases. Specifically, the alloy may include 33.0 to 33.2% by weight of copper, 43.0 to 43.5% by weight of nickel, 5.0 to 5.6% by weight of cobalt, 17.0 to 17.5% by weight of iron, and other impurities.

The melt-reduction is preferably performed at 1300 to 1500 ° C. When the above-mentioned melt-reduction is carried out at a temperature lower than 1300 ° C, there is a problem that an alloy phase containing copper, nickel, cobalt and iron can not be obtained. When the temperature is higher than 1500 ° C, From the viewpoint of efficiency and cost reduction, it is preferable that the temperature is 1500 DEG C or less.

Next, a method for producing a sulfide from deep sea manganese nodules using the oxide flux according to the present invention includes a step (S20) of adding a waste stone, a reducing agent and an oxide flux to the alloy and dry-smelting the sulfide to produce the sulfide.

It is preferable that the above-mentioned waste rock (CaSO ₄ · H ₂ O) is added in an amount of 150 to 270 g based on 100 g of the alloy. It is possible to consider all the phases of the sulfide that can be produced to set the content of the waste rock and to determine the combination of the phases thermodynamically most stable in the process. When the amount of the waste stover is less than 270 g, the amount of sulfur contained in the sulfide is low. When the amount of the waste stover is more than 270 g, the amount of the sulfide is more lost in the gaseous phase than the sulfur reacting with the alloy. There is a problem that sufficient sulfur is not contained in the solution.

The reducing agent is added to efficiently decompose the waste rock, and carbon and the like can be used.

The reducing agent is preferably added in such a manner that the weight ratio of the waste sludge: reducing agent is 17: 5 to 9 with reference to the following Reaction Scheme 1. When the reducing agent is contained in an amount of less than 5, there is a problem that the amount of decomposed waste rock is small and the sulfur content is low. When the reducing agent is more than 9, a reducing agent is added more than necessary.

[Reaction Scheme 1]

CaSO ₄ + 4C = CaS + 4CO

The oxide flux may be at least one selected from the group consisting of Al ₂ O ₃ and Fe _t O (ratios of 0 < _t < 1), and the Al ₂ O ₃ may control the elution of the alumina crucible , And Fe _t O can be used to increase the reaction efficiency by the formation of liquid slag. In the Fe _t O, t may be a rational number of 0 &lt; t &lt; 1, but more specifically, 2/3, 3/4 or 1.

The oxide flux is preferably added in an amount of 5 to 15 parts by weight based on the total weight of the waste stone. When the amount of the oxide flux is less than 5 parts by weight, the dry smelting process must be performed for more than 3 hours. When the amount of the oxide flux is more than 15 parts by weight, a large amount of oxide flux is added to generate impurities in the sulfide, There is a problem.

In addition, the dry smelting is preferably performed at 1360 to 1500 ° C. Nickel, cobalt and iron are not melted when the dry smelting is carried out at a temperature lower than 1360 ° C. When the temperature is higher than 1500 ° C, a large amount of energy is consumed and the sulfur content in the slag there is a problem in that the sulfur content in the sulfide is not increased due to an increase in the sulfide capacity.

[Reaction Scheme 2]

[S] _alloy + (O ^{2 -} ) _slag = (S ^{2 -} ) _slag + 1 / 2O ₂ (g)

At this time, the dry smelting is performed while supplying Ar, CO, CO ₂ and SO ₂ , in order to promote sulfide formation and to produce a stable sulfide.

In the case of the dry smelting, when the oxide flux is not added, the dry smelting is performed for 3 to 4 hours to produce a sulfide containing at least 20% by weight of sulfur. However, when the oxide flux is added, Min to 2 hours and 30 minutes to prepare a sulfide containing at least 20% by weight of sulfur. It is believed that this is due to the fact that oxide flux is involved in CaSO ₄ decomposition to form a liquid compound to improve the reaction rate.

Example 1: Preparation of a sulfide having a sulfur content of 20% by weight or more

The deep-sea manganese nodule was crushed, dried and then melted and reduced at 1400 ° C to prepare an alloy of Cu-Ni-Co-Fe. To 100 g of the alloy thus prepared, 270 g of CaSO ₄ .H ₂ O was added as a raw material of sulfur. Carbon was added as a reducing agent so that the weight ratio of exhaust gas to carbon was 17: 5. As the oxide flux, Al ₂ O ₃ and FeO were added in an amount of 5 parts by weight based on the total weight of the waste stone, and the mixture was dry-smelted at 1400 ° C. for 2 hours and 30 minutes to prepare a mat-phase sulfide having a sulfur content of 20 wt% or more.

The dry smelting was performed using the supercanal electric resistance furnace shown in FIG. 2, and was performed in an atmosphere of Ar, CO, CO ₂ and SO ₂ .

Table 1 below shows the compositions of the alloys produced by crushing and drying the deep sea manganese nodules and then melting and reducing them.

metal Cu Ni Co Fe weight% 33.2 43.5 5.6 17.5

In order to set the amount of waste stones relative to the alloy, all the phases of the sulfides that can be produced through the thermodynamic calculator were considered, and the combination of the most thermodynamically stable phases in the above production method was selected to calculate the amount of the waste stones needed This is shown in Table 2 below.

sulfide Sulfur content (% by weight) Amount of waste stones needed (g) Cu ₂ S 27.032 156.97 Ni ₃ S ₂ Co ₉ S ₈

Experimental Example 1: Analysis of change in sulfur content over time without addition of oxide flux

In the method of producing sulfides from deep sea manganese nodules using the oxide flux according to the present invention, the change of the sulfur content in the sulfides according to the dry smelting time was analyzed when the dry smelting process was performed without adding the oxide flux, Respectively.

As shown in FIG. 3, when the dry smelting process was performed for about 3 hours, the sulfur content in the sulfide was found to be not less than 20% by weight, and the sulfur content was not changed even after the dry smelting time was increased.

Experimental Example 2: Analysis of change in sulfur content according to addition amount of oxide flux

In order to investigate the change of the sulfur content in the sulfide according to the addition amount of the oxide flux in the method of producing the sulfide from the deep sea manganese nodule using the oxide flux according to the present invention, the amount of the Al ₂ O ₃ flux was fixed to 5 wt% and 15 wt% The change in sulfur content in the sulfide was observed while varying the Fe _t O flux amount from 5 to 15 wt%, and the results are shown in Fig.

CaSO ₄ is decomposed into CaO and CaS by the reducing agent and the oxide flux, and the amount of oxide flux added (g (g)) corresponding to 5 wt%, 10 wt% and 15 wt% based on the weight percentage and molecular weight of CaO and CaS in the slag ). At this time, the ratio of the amount of CaSO ₄ and the amount of flux (based on 5 wt%) was set at about 1: 0.04. The sulfur content of the matte phase was analyzed by a C / S analyzer.

As shown in Fig. 4, there was almost no change in the sulfur content in the sulfide depending on the amount of flux added. In addition, it was confirmed that when the Al ₂ O ₃ and Fe _t O fluxes were added by 5 wt% each, the time for the sulfur content in the matte phase to reach saturation was shorter than that in the case of adding only the waste plaster and the carbon reducing agent. This is attributed to the formation of a liquid compound by the participation of Fe _t O flux in the CaSO ₄ decomposition, thereby increasing the driving force of the decomposition reaction. If the amount of the oxide flux added is more than 15 wt%, it will be disadvantageous in terms of the process cost. If the amount of the oxide flux is less than 5 wt%, the sulfur content of 20 wt% .

Experimental Example 3: Analysis of Sulfur Content Changes with Drying Time

The sulfur content in the sulfides was analyzed according to the dry-smelting time in the process for producing sulfides from deep sea manganese nodules using the oxide fluxes according to the present invention, and the results are shown in FIG.

As shown in FIG. 5, when 5 wt% of Al ₂ O ₃ and FeO were respectively added, the sulfur content in the sulfide reached 20 wt% in the dry smelting process for about 2 hours and 10 minutes, Sulfur content was the maximum, and after 2 hours and 30 minutes, the sulfur content did not increase any more. Therefore, it can be seen that the dry smelting is preferably performed for 2 hours 10 minutes to 2 hours 30 minutes in the process for producing sulfides from deep sea manganese nodules using the oxide flux according to the present invention.

Although the present invention has been described with respect to the method for producing sulfides from deep sea manganese nodules using the oxide flux according to the present invention, it is apparent that various modifications can be made without departing from the scope of the present invention.

Therefore, the scope of the present invention should not be limited to the above-described embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

It is to be understood that the foregoing embodiments are illustrative and not restrictive in all respects and that the scope of the present invention is indicated by the appended claims rather than the foregoing description, It is intended that all changes and modifications derived from the equivalent concept be included within the scope of the present invention.

Claims (12)

Crushing and drying the deep sea manganese nodule, followed by melt reduction to produce an alloy; And
Adding a waste stone, a reducing agent and an oxide flux to the alloy, and dry-smelting the powder at 1360 to 1500 ° C for 2 hours to 10 minutes to 2 hours and 30 minutes to produce a sulfide having a sulfur content of 20 to 25% by weight ,
Wherein the oxide flux is added in an amount of 5 to 15 parts by weight based on the total weight of the densified manganese oxide.
The method according to claim 1,
Wherein the melt reduction is performed at 1300 to 1500 ° C.
The method according to claim 1,
Wherein said alloy comprises copper, nickel, cobalt and iron. &Lt; Desc / Clms Page number 20 &gt;
The method according to claim 1,
Wherein the alloy contains 33.0 to 33.2% by weight of copper, 43.0 to 43.5% by weight of nickel, 5.0 to 5.6% by weight of cobalt, 17.0 to 17.5% by weight of iron, and other impurities. &Lt; / RTI &gt;
The method according to claim 1,
Wherein the waste scum is added at 150 to 270 g based on 100 g of the alloy.
The method according to claim 1,
Wherein the reducing agent is carbon. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt;
The method according to claim 1,
Wherein the reducing agent is added in an amount of 17: 5 to 9 by weight of a waste sludge: reducing agent.
The method according to claim 1,
Wherein the oxide flux is at least one selected from the group consisting of Al ₂ O ₃ and Fe _t O (ratios of 0 <t≤1).
delete delete The method according to claim 1,
Wherein the dry smelting is performed while supplying Ar, CO, CO ₂ and SO ₂ .
delete

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