JP3411320B2 - Zinc smelting method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrometallurgical process for zinc, and more particularly, it has been improved by reasonably combining a conventional hydrometallurgical process including oxidative roasting and a direct pressure leaching process for zinc concentrate. In addition to almost completely recovering valuable metals such as gold, silver, lead, and zinc contained in zinc concentrate, iron is effectively used as an iron raw material for other industries, sulfur is used as elemental sulfur, and free sulfuric acid is used. Relates to a hydrometallurgical process for zinc concentrate in which all valuable metal components in the zinc concentrate are separated and recovered by recovering as gypsum.

[0002]

2. Description of the Related Art In the conventional hydrometallurgical process for zinc, zinc concentrate containing zinc oxide, iron, etc. as sulfides is oxidized and roasted at 900 to 1000 ° C. in a roasting furnace to make zinc oxide the main component. Zinc calcined ore, which is leached into a zinc electrolytic tail solution (dilute sulfuric acid) to form a zinc sulfate solution, which is subjected to electrolytic extraction to smelt metallic zinc. In the process of roasting zinc concentrate, the sulfur present in the zinc concentrate becomes sulfurous acid gas (SO ₂ ) from the form of sulfide, so it cannot be released into the atmosphere as it is, and this is generally used as a raw material. As concentrated sulfuric acid is manufactured.

The zinc leaching residue generated when leaching zinc calcined ore into dilute sulfuric acid is a reddish brown mud consisting of 15 to 25% zinc and 20 to 30% iron containing zinc ferrite (zinc ferrite) as main components. Almost all of the gold, silver, and lead contained in the zinc concentrate and part of the copper are left undissolved in the zinc concentrate.

Zinc, gold, silver contained in the zinc leaching residue,
As a method for recovering lead and the like, both a dry method and a wet method have been developed and are currently in operation. In the wet method, zinc in the zinc leaching residue, iron is dissolved in a zinc electrolytic tail solution and leached into the solution, gold, silver, lead, etc. are recovered as a residue, and the eluted iron is a good jarosite, Zinc is recovered as a zinc sulfate solution by forming the form of goethite, hematite, etc., precipitating, filtering and separating from the solution. Generally, when a zinc leaching residue is leached with a zinc electrolytic tail solution, a high temperature and high acid leaching method is used. Furthermore, in order to precipitate iron in the leachate as jarosite, goethite, and hematite, a reduction process of ferric iron by zinc concentrate and a neutralization process of free sulfuric acid in the leachate by zinc calcining are required as pre-processes. Become.

Sulfuric acid must be produced inevitably in the process of oxidizing and roasting zinc concentrate, and the amount of capital investment for these is enormous. Not tied together, and due to fluctuations in demand for sulfuric acid,
As a result, the throughput of zinc concentrate, that is, the production of electrolytic zinc is controlled. In addition, as a wet treatment method for zinc leaching residue,
When high-temperature high-acid leaching of zinc leaching residue, reduction with zinc concentrate, and neutralization with zinc sinter are carried out, the recovery rate of zinc, silver, etc. is reduced and impurities (aluminum, arsenic) that interfere with the hydrometallurgical process are reduced. When iron is removed in the form of jarosite or goethite, these must be discarded in the dam because they are reddish brown mud. , The problem of environmental management tends to occur.

On the other hand, as a smelting method without generation of sulfurous acid gas, zinc concentrate is leached at high temperature with dilute sulfuric acid under oxygen pressure to recover zinc as a zinc sulfate solution, and sulfur existing in the form of sulfide is used as a simple substance. A direct pressure leaching method for zinc concentrate, which is recovered as sulfur, has also been implemented. However, even in this method, the same problems as in the wet treatment method of the zinc leaching residue such as recovery of valuable metals, removal of iron and removal of impeding impurities have occurred. Furthermore, in this method, it is conceivable that the fluorine removed in the oxidizing and roasting process of zinc concentrate will be concentrated in the smelting process, resulting in problems in electrolysis. Is required.

[0007]

DISCLOSURE OF THE INVENTION The present invention improves on a combination of the known direct pressurization / leaching method for zinc concentrate and wet treatment method for zinc leaching residue, and thereby improves gold, silver and lead in zinc concentrate. The purpose is to improve the recovery rate of valuable metals such as copper, increase the added value, improve the quality of iron-containing residues, and improve the method for removing impurities that interfere with the smelting process.

[0008]

SUMMARY OF THE INVENTION The present invention combines the known direct pressure leaching process for zinc concentrate with conventional wet processing of zinc leaching residue to produce gold in zinc concentrate and zinc leaching residue.
Valuable metals such as silver, copper, and lead are almost completely recovered, and iron in zinc concentrate and zinc leaching residue is used as an iron raw material for other industries to eliminate waste and to directly add zinc concentrate. It has features such as enabling removal of fluorine, which has been pointed out as a problem of the pressure leaching method, which impairs electrolysis.

The present invention comprises the following steps (a) to (j).

(A) A leaching solution (No. 1) consisting of a zinc sulfate solution is obtained by leaching a roasted ore obtained by roasting a zinc concentrate with a sulfuric acid-containing solution.
Leachate) and gold, to give silver, lead, and zinc leach residue containing iron (No.1 residue), first feeding the leachate to the zinc electrolysis step
Process.

(B) A solution containing sulfuric acid (zinc electrolytic tail solution and concentrated sulfuric acid) and ferric sulfate (a deironization obtained by treating a zinc leaching residue) under a pressure-oxidizing atmosphere in which zinc concentrate is introduced oxygen. and leached with a liquid) and solid-liquid separation, see contains zinc, a component such as copper and cadmium, free sulfuric acid concentration 20 g / l
Hereinafter, a leachate with an iron concentration of 3 g / l or less (No. 2 leachate) and a leach residue containing gold, silver, lead, iron and elemental sulfur components (No. 2).
2 residue) and the leaching solution containing the sulfuric acid for leaching the ore.
The second step you fed to the first step as a chromatic solution.

(C) Leaching residue (N
o. Sulfur residue (N residue) which was concentrated by sulfur by flotation
o. (3.1 residue) and gold / silver / concentrated gold, silver, lead, and iron
Third step of separating into lead / iron residue (No. 3/2 residue) .

(D) Melting temperature of the sulfur single substance obtained by the third step is the sulfur residue (No. 3.1 residue) enriched with the single sulfur.
Fourth step of heating to a temperature range and melt-filtering to obtain elemental sulfur and unreacted zinc concentrate.

(E) Gold / silver / lead / iron residue (No. 3, 2 residue ) obtained by concentrating gold, silver, lead and iron obtained in the third step
Residue) in a sulfurous acid gas atmosphere at a high temperature of 100 ° C or higher.
Leach with a sulfuric acid-containing solution such as lead electrolytic tail solution, perform solid-liquid separation, and then leach
Leachate obtained by transferring iron into the liquid (No. 5
Leachate) and gold, silver, and lead residues with concentrated gold, silver, and lead
(No. 5 residue) and the fifth step.

(F) Zinc leaching residue obtained in the first step
(No. 1 residue), preferably in the presence of elemental sulfur, 10
In a pressurized sulfurous acid gas atmosphere at a high temperature of 0 ° C. or higher, the leachate (No. 5 leachate) obtained in the fifth step (e ) and a sulfuric acid-containing solution such as a zinc electrolytic tail solution are leached for solid-liquid separation, A
Leachate obtained by transferring lead and iron into the leachate
(No. 6 leachate) and gold, silver, and lead-rich gold / silver /
The sixth step of obtaining a lead residue (No. 6 residue) .

(G) The leachate obtained in the sixth step (No.
6 leachate) to which calcium carbonate or calcium hydroxide or the like is added to perform two-stage neutralization, and then solid-liquid separation is performed to obtain gallium and indium accumulated from the neutralizing solution containing zinc and iron. And a second gypsum, and the second gypsum is gallium,
Seventh step shall be the recycled material of indium.

(H) The neutralization solution obtained in the seventh step is added to 16
After the iron removal treatment in a pressurized oxidizing atmosphere with introduced oxygen at a high temperature of 0 ° C. or more, solid-liquid separation is performed to obtain iron oxide and a deironization liquid, and the iron removal containing sulfuric acid and ferric sulfate. Liquid
8 fed to the second step as the solution for lead concentrate leaching
Process. And using the elemental sulfur obtained in the fourth step
The high-purity sulfur dioxide produced is used in the fifth and sixth steps
Ninth step used for gas atmosphere.

Furthermore, the gold, silver, lead, and iron residues (No. 3, 2 residues) generated in the third step are directly transferred to the sixth step, and the fifth step is omitted, and part of the sixth step Changed the following steps.

(I) Gold / silver / lead / iron residue (No. 3, 2 residue ) obtained by concentrating gold, silver, lead and iron obtained in the third step
The residue) together with the zinc leaching residue ( No. 1 residue) obtained in the first step was treated with a sulfuric acid-containing solution such as a zinc electrolytic tail solution in a pressurized sulfurous acid gas atmosphere at a high temperature of 100 ° C. or higher. After the leaching, the sixth step omitting the fifth step of solid-liquid separation to transfer iron into the leaching solution and concentrating gold, silver and lead in the gold / silver / lead residue (No. 6 residue) .

(J) Remove the zinc leaching residue ( No. 1 residue) to 1
After leaching into the leachate from the 5th step (No. 5 leachate) and the zinc electrolytic tail solution in a pressurized sulfurous acid gas atmosphere at a high temperature of 00 ° C or higher , solid-liquid separation is performed, and zinc, copper, iron, etc. are in the leachate. And a concentrated residue of gold, silver and lead was obtained, and a decoppering agent such as hydrogen sulfide was added to the obtained leachate to concentrate the copper, gold, silver, lead and copper residue (No. .6 remaining
Process of obtaining a residue .

The structural features of the present invention will be described in more detail in (1) to (6) below.

(1) The first step is a leaching step in conventional wet zinc smelting. As mentioned above, this zinc concentrate
Sulfuric acid is inevitably produced in the process of oxidizing and roasting
Must be dealt with, and due to fluctuations in the demand for sulfuric acid,
Limitation of ore throughput or electrozinc production
become. Therefore, the sulfur in the zinc concentrate can be recovered by itself.
Direct pressure leaching method (second step) of zinc concentrate
Will be. The ratio of zinc concentrate used in both processes is
It is decided in consideration of the profitability .

(2) In the second step, the zinc concentrate is leached with a deferred solution and a zinc electrolytic tail solution under high temperature and oxygen pressure. In this case, the leaching reaction is promoted due to the use of the deferred liquid containing ferric ions. Further, by setting the concentration of free sulfuric acid in the leachate at the end of leaching to 20 g / l or less, iron ions in the leachate form jarosite and hematite, and precipitate and precipitate from the solution. Therefore, in the first step, which is a smelting ore leaching step in which the leaching solution is repeated, it is possible to suppress the enhancement of equipment as the iron load increases.

(3) In the fifth step, the gold, silver, lead and iron-concentrated residue obtained in the third step is leached with a zinc electrolysis tail solution in a sulfurous acid gas reducing atmosphere at high temperature and under pressure of sulfurous acid gas. Because of this, the iron in the residue dissolves almost completely. Therefore, an extremely low iron-containing residue containing gold, silver, and lead can be obtained and recovered as a high-value-added lead smelting raw material. However, this step can be omitted. Further, the sulfurous acid gas in this case can be manufactured inexpensively by using the elemental sulfur from the fourth step.

(4) In the sixth step, the zinc leaching residue or the gold, silver, lead and iron concentrated residue obtained in the third step and the zinc leaching residue are obtained in the former step with the zinc electrolytic tail solution and the fifth step. The mixed solution of the obtained leachate, in the latter case, only the zinc electrolytic tail solution is used to add the elemental sulfur generated in the fourth step to perform the leaching in the sulfurous acid gas reducing atmosphere at high temperature and under the pressure of the sulfurous acid gas, so that even low concentration sulfuric acid can be obtained. The reaction becomes active and is completed in a short time, and zinc and iron in the residue are almost completely transferred into the leachate. Therefore, a residue having a high lead content can be recovered. Further, this is subjected to flotation to obtain a copper smelting raw material and a lead smelting raw material. In addition, if leaching in a sulfurous acid gas reducing atmosphere is performed without adding elemental sulfur, the copper will migrate into the leaching solution, and the residue recovered will be a gold- and silver-containing residue containing lead as the main component, and without going through a flotation process. It becomes a lead smelting raw material. On the other hand, copper in the leachate is precipitated by adding a decoppering agent such as hydrogen sulfide and recovered as a copper residue. Further, the sulfurous acid gas in this case can be manufactured inexpensively by using the elemental sulfur from the fourth step.

(5) In the seventh step, the leachate obtained in the sixth step is treated with calcium carbonate, calcium hydroxide, etc.
Neutralize the stage. In the first stage, mainly free sulfuric acid in the leachate was fixed as gypsum, and in the second stage, aluminum in the liquid was
Impurities such as arsenic and fluorine, which impair hydrometallurgical zinc smelting, are removed by coprecipitation with gypsum. The gypsum contains rare metals such as gallium and indium and is a raw material for recovering these metals.

(6) In the eighth step, the iron leached in the neutralization solution obtained in the seventh step is kept in a high temperature oxygen pressurized atmosphere to precipitate as hematite from the solution. The obtained hematite can be used as an iron raw material for other industries without purification.

In the final step of iron removal, sulfurous acid gas is used for reducing leaching and a calcium-based neutralizing agent is used for neutralization as shown in the above-mentioned steps (1) to (5). Since the iron concentration can be maintained high without increasing the zinc concentration of, the energy cost per iron removal amount can be reduced. The iron removal solution after iron removal is repeated to the second step of leaching the zinc concentrate.

The present invention will now be described in detail with reference to FIGS. 1 and 2. Note that FIG. 2 is a system diagram in which the fifth step is omitted.

The first step is the leaching step of zinc ore in the conventional hydrometallurgical process.

The second step is a known method in which zinc concentrate is leached in sulfuric acid under high temperature and pressure of oxygen, but in the present invention, a solution containing sulfuric acid is used in addition to the zinc electrolytic tail solution which has been used so far. A deferred liquid containing ferric ions is also used. That is, a zinc electrolytic tail solution and a deferred solution are added to zinc concentrate, and the reaction is carried out by maintaining the temperature above the melting point of sulfur and the oxygen partial pressure of ² to 15 kg / cm ² for 1 hour or more in a closed container (autoclave), Leach zinc, iron, copper, cadmium, etc. into the solution. In this case, the amount of zinc electrolytic tail solution and deferred solution should be such that zinc, copper, cadmium, iron and lead react in a predetermined amount, and the free sulfuric acid concentration in the leaching solution at the end of leaching is 20 g / l or less. By setting, iron in the leachate will precipitate and precipitate as jarosite and hematite, and the iron ion concentration will be 3 g / l or less. After the leaching, the slurry is separated into solid and liquid, the leaching solution is repeated to the leaching step of the ore, and the leaching residue is sent to the third step.

In the third step, the residue obtained by direct pressure leaching of the zinc concentrate is subjected to flotation, and the residue containing elemental sulfur and unreacted concentrate is floated, and the residue containing iron, lead, gold, silver, etc. is tailed. Is a known method. Floating ore consisting of elemental sulfur and unreacted concentrate obtained in the third step is sent to the fourth step, and tailings containing iron, lead, gold, silver, etc. are sent to the fifth step.

The fourth step is a known method of melting and filtering the floating ore containing the elemental sulfur and unreacted zinc concentrate obtained in the third step. The elemental sulfur in the floating ore is melted and filtered, and the unreacted zinc concentrate remains as a filter residue. A part of the obtained elemental sulfur is repeated to the sixth step, and the unreacted zinc concentrate is repeated to the roasting step.

The fifth step is iron, lead obtained in the third step,
Zinc electrolytic tail solution is added to tailing residue containing gold, silver, etc.,
In a closed vessel (autoclave), in a pressurized sulfur dioxide gas atmosphere, hold at 100 ° C. or higher for 30 minutes or more to react, leaching iron as ferrous ion into the solution, and gold, silver, lead, etc. in the residue It is a method of concentrating and collecting. The amount of zinc electrolytic tail solution added is set so that the ferrous ion concentration in the leachate is below the solubility. The leachate obtained in this step is repeated in the sixth step. This step is omitted in FIG.

In the sixth step, the zinc leaching residue obtained by leaching the calcined ore was added with the leachate obtained in the fifth step, the zinc electrolytic tail solution and the elemental sulfur obtained in the fourth step, and the vessel was closed (autoclave). The reaction is carried out by holding in a pressurized sulfurous acid gas atmosphere at 100 ° C. or higher for 1 hour or longer, and zinc, iron, cadmium, etc. are dissolved in the solution, and gold, silver, copper, and lead are concentrated and recovered in the residue.

The amount of sulfur added is an amount suitable for fixing the copper in the zinc leaching residue as copper sulfide. The amount of zinc electrolytic tail solution to be added is to react with predetermined amounts of zinc, iron and cadmium, and the free sulfuric acid concentration in the leaching solution at the end of leaching is 40 in order to optimize the amount of gypsum generated in the next step in the process. ~
Set it to be 60g / l.

In the seventh step, the neutralized solution obtained in the sixth step is heated to 50 to 80 ° C., and free sulfuric acid is neutralized in two steps with calcium carbonate, calcium hydroxide or the like to recover gypsum. The first stage neutralization is performed at a pH of about 1.0, and recovered as high-quality gypsum with few impurities. The second stage neutralization is performed at a pH of about 4.0 to coprecipitate and absorb aluminum, arsenic, and fluorine. To remove. Valuable metals such as gallium and indium existing in the solution are also recovered from the gypsum in the second stage.

Fluorine leached in the direct pressure leaching step of zinc concentrate is removed in this step via direct pressure leaching solution and zinc electrolytic tail solution. However, the amount of liquid treated in the second stage neutralization is equivalent to the amount of aluminum, arsenic, fluorine, etc. that is removed to such an extent that it does not concentrate in the hydro-zinc smelting system to the extent that it interferes with zinc electrolysis. Is the amount.

In the eighth step, the neutralization solution obtained in the seventh step is heated to 160 ° C. in a closed container (autoclave) under pressure of oxygen.
By holding above, the ferrous ions in the solution are hydrolyzed to become high-purity iron oxide containing hematite as a main component, and are precipitated and recovered from the solution. The solution from which iron has been removed is repeatedly used as a deironing solution in the second step, which is a direct pressure leaching step for zinc concentrate.

The method according to the present invention in which the direct pressure leaching method for zinc concentrate and the hydrometallurgical method for zinc leaching residue are combined in a unique manner has been described in detail above, but will be described more specifically by way of examples.

[0041]

【Example】

(1) Second step: 2,250 g of zinc concentrate, deferred liquid 14.
5 liters (l) and 1.5 liters of zinc electrolytic tail solution were added, and leaching was performed for 90 minutes in a closed container (autoclave) at a temperature of 150 ° C. and oxygen pressure of 12 kg / cm ² . The results obtained are shown in Table 1. It can be seen that most of the zinc in the zinc concentrate migrates into the leachate, and the total amount of gold, silver and lead, and part of the copper accumulate in the leach residue.

[0042]

[Table 1] (2) Third step; leach residue 1,54 obtained in the second step
The leachate obtained in the second step was added to 1 g to make a slurry, and then flotation was performed. The results are shown in Table 2.
It can be seen that elemental sulfur is separated.

[0043]

[Table 2] (3) Fourth step: 691 g of the float ore obtained in the third step was melt-filtered at a temperature of 130 ° C. The results obtained are shown in Table 3. It is understood that 99.98% or more of elemental sulfur can be recovered from the floating ore.

[0044]

[Table 3] (4) Fifth step: 861 g of tailing residue obtained in the third step
5.7 liters of zinc electrolysis tail solution is added to, and the temperature is 110 ° C in a closed container (autoclave), and sulfur dioxide gas pressure is 2 kg / c.
Leaching was carried out for 60 minutes under the condition of m ² . Table 4 shows the obtained results.
Shown in. Zinc and iron in tailings migrate to the leachate, gold,
It can be seen that silver, lead and copper accumulate in the residue.

[0045]

[Table 4] (5) Sixth step: 5.8 liters of the leachate obtained in the fifth step was added to 2380 g of zinc leaching residue, and the temperature was 110 ° C. in a closed container (autoclave), and the pressure of sulfurous acid gas was 2 kg / c.
Leaching was performed for 90 minutes under the condition of m ² . Table 5 shows the obtained results.
Shown in. Zinc and iron in the zinc leaching residue are transferred to the leachate,
Since gold, silver, copper, and lead accumulate in gold, silver, copper, and lead residues,
It can be seen that the amount of iron in the residue is small and the value added is high.

[0046]

[Table 5] (6) Seventh step; calcium carbonate is added in a slurry form to 11.8 liters of the leachate obtained in the sixth step, neutralized to a temperature of 70 ° C. and pH 1.0, and pH of 1.0 is further recovered after recovering gypsum. 40% of the neutralized solution of 1 was added to form a slurry of calcium carbonate, and the mixture was neutralized to a temperature of 70 ° C. and pH 4.0. The obtained results are shown in Table 6. It can be seen that iron, aluminum, arsenic, fluorine, gallium, and indium in the leachate are accumulated in the second stage gypsum.

[0047]

[Table 6] (7) Eighth step; 14.8 liters of the neutralization solution obtained in the seventh step was heated at a temperature of 200 in a closed container (autoclave).
The reaction was carried out for 120 minutes under the conditions of ° C and oxygen pressure of 18 kg / cm ² . The results obtained are shown in Table 7. It can be seen that zinc in the neutralization solution migrates to the deferred solution, residual iron becomes trivalent ions (ferric), and sulfate radicals form free sulfuric acid.

[0048]

[Table 7]

[0049]

The effects of the present invention are as follows: (1) By using the deironing solution generated in the deironing process in the zinc concentrate pressure leaching process, the pressure leaching reaction is promoted and the iron content is increased. In the smelting ore leaching step in which the leaching solution containing less iron is repeated, equipment accompanying an increase in iron load can be suppressed as much as possible. Further, since the zinc concentrate is directly subjected to the pressure leaching process, the sulfuric acid is not produced and it is not necessary to increase the sulfuric acid production facility. (2) Gold, silver, lead, and iron residues generated in the zinc concentrate pressure leaching process are repressurized and leached to remove iron, or mixed with the zinc leaching residue generated in the calcined leaching process and added. By leaching under pressure to remove iron, it can be recovered as a lead material with high added value. (3) Gallium in zinc concentrate,
Since gallium and indium are coprecipitated and adsorbed on gypsum and discharged to the outside of the system, gallium and indium can be recovered, and fluorine, which is an obstacle to the zinc electrolysis process, can be removed.

Therefore, in the conventional zinc smelting, gold in zinc concentrate, which was impossible by either wet method or dry method,
All components such as silver, lead, copper, iron, indium, gallium, and sulfur are reasonably recovered, and the generation of slag that has been a problem to clean the environment in the past is eliminated, and sulfuric acid does not bring profits. It has become possible to reduce manufacturing equipment.

[Brief description of drawings]

FIG. 1 is a system diagram showing a combination of steps of a zinc smelting method according to the present invention and a physical distribution.

FIG. 2 is a system diagram in which a fifth step (pressure reduction step with sulfurous acid gas) in FIG. 1 is omitted.

Continuation of the front page (56) Reference JP 4-311541 (JP, A) JP 63-93832 (JP, A) JP 57-79136 (JP, A) (58) Fields investigated (Int .Cl. ⁷ , DB name) C22B 1/00-61/00

Claims (6)

(57) [Claims] (1) A leachate (No. 1) made of a zinc sulfate solution by leaching a calcined ore obtained by roasting a zinc concentrate with a sulfuric acid-containing liquid (No. 1).
Leachate) and gold, to give silver, lead, and zinc leach residue containing iron (No.1 residue), first feeding the leachate to the zinc electrolysis step
Process; (2) Zinc concentrate is leached with a solution containing sulfuric acid and ferric sulfate under a pressure-oxidizing atmosphere with introduced oxygen to perform solid-liquid separation, and free sulfuric acid concentration is 20 g / l or less, iron concentration is 3 g /
Leachate of 1 or less (No. 2 leachate) and leach residue (No. 2 residue)
To obtain the leaching solution as the sulfuric acid-containing solution for leaching ore.
The second step you fed to the first step Te; (3) the second resultant leach residue in step (No.2 residue) flotation to sulfur residue sulfur enriched (No.3 · 1 residue ) And gold, silver, lead, iron concentrated gold / silver / lead / iron residues (No. 3 and 2 residues) in the third step; (4) Sulfur residue obtained in the third step (No. .3
4th step of obtaining single sulfur and unreacted zinc concentrate by heating (1 residue) to a melting temperature range of single sulfur and performing melt filtration.
(5) Gold, silver, lead, iron residue (No. 3) obtained in the 3rd process
・ 2 residue) is leached with a sulfuric acid-containing liquid in a sulfurous acid gas atmosphere at a high temperature of 100 ° C. or more to perform solid-liquid separation, and a leachate (No. 5 leachate) obtained by transferring iron into the leachate is obtained. Fifth step of obtaining gold / silver / lead residue (No. 5 residue); (6)
100% of the zinc leaching residue (No. 1 residue) obtained in the first step
Obtained by leaching with the leachate (No. 5 leachate) obtained in the 5th step and the sulfuric acid-containing solution in a sulfurous acid gas atmosphere at a high temperature of ℃ or higher to perform solid-liquid separation, and transferring zinc and iron into the leachate. The sixth step for obtaining the obtained leachate (No. 6 leachate) and the gold, silver and lead residue (No. 6 residue); (7) The leachate obtained in the sixth step (No. 6 leachate) is calcium carbonate or After two-stage neutralization with calcium hydroxide, solid-liquid separation is performed to obtain a neutralization liquid containing zinc and iron, and a second gypsum made of gypsum containing accumulated gallium and indium . 2 gypsum gully
Um, the seventh step shall be the recycled material indium; (8) After the neutralized solution obtained in the seventh step to deferrisation treated in pressurized oxidation atmosphere by introducing oxygen at a high temperature of at least 160 ° C.,
Solid-liquid separation is performed to obtain iron oxide and deferred liquid , and sulfuric acid and sulfuric acid are added.
Said solution for leaching zinc concentrate containing said deironization liquid containing ferric iron
(9) Fourth step: the eighth step you fed to the second step as
High-purity sulfur dioxide gas produced using the obtained elemental sulfur
Ninth process used in the sulfur dioxide gas atmosphere in the fifth and sixth processes
A process for smelting zinc, characterized in that each valuable metal component in the zinc concentrate is separated and recovered, including each process as a main process. 2. A leaching solution (No. 1) comprising a zinc sulfate solution obtained by leaching a calcined ore obtained by roasting a zinc concentrate with a sulfuric acid-containing solution.
Leachate) and gold, to give silver, lead, and zinc leach residue containing iron (No.1 residue), first feeding the leachate to the zinc electrolysis step
Process; (2) Zinc concentrate is leached with a solution containing sulfuric acid and ferric sulfate under a pressure-oxidizing atmosphere with introduced oxygen to perform solid-liquid separation, and free sulfuric acid concentration is 20 g / l or less, iron concentration is 3 g /
A leachate of 1 or less (No. 2 leachate) and a leach residue (No. 2 residue) are obtained , and the leachate is used as the sulfuric acid-containing solution for leachate leaching.
The second step you fed to the first step as; (3) the second resultant leach residue in step (No.2 residue) flotation to sulfur residue sulfur enriched (No.3 · 1 residue ) And gold, silver, lead, iron concentrated gold / silver / lead / iron residues (No. 3.2 residue); the third step; (4) Sulfur residue (N) obtained in the third step.
o. (3.1 residue) is heated to the melting temperature range of elemental sulfur and melt-filtered to obtain elemental sulfur and unreacted zinc concentrate. (4) (5) Zinc leaching residue (No. .1 residue) and gold / silver / lead / iron residue (N
o. (3.2 residue) is leached with a sulfuric acid-containing liquid in a sulfurous acid gas atmosphere at a high temperature of 100 ° C. or higher for solid-liquid separation, and a leachate obtained by transferring zinc and iron into the leachate (N
o. 6 leaching solution) and a gold / silver / lead residue (No. 6 residue) 6th step; (6) 2 steps of leaching solution (No. 6 leaching solution) obtained in 6th step with calcium carbonate or calcium hydroxide After neutralization, solid-liquid separation is performed, and the second stone is composed of gypsum containing a neutralizing solution containing zinc and iron and accumulating gallium and indium.
To give a paste, the second gypsum gallium recovery of indium
Seventh step shall be the raw material; (7) after removing the iron treated in pressurized oxidation atmosphere by introducing oxygen at a high temperature neutralization solution over 160 ° C. obtained in the seventh step, and solid-liquid separation oxide Obtaining iron and a deferred solution and containing sulfuric acid and ferric sulfate
Eighth step of sending the solution to the second step as the solution for leaching zinc concentrate ; (8) Using elemental sulfur obtained in the fourth step
The high-purity sulfur dioxide gas produced by
A zinc smelting method characterized in that each of the valuable metal components in the zinc concentrate is separated and recovered, including each of the ninth step of using an atmosphere; as a main step. 3. The copper is concentrated in the residue obtained by allowing the elemental sulfur obtained in the fourth step to be present in the sulfuric acid-containing liquid in the sixth step and leaching the zinc leaching residue. The zinc smelting method according to claim 1. 4. The leaching of the zinc leaching residue and the gold / silver / lead / iron residue by allowing the elemental sulfur obtained in the fourth step to be present in the sulfuric acid-containing liquid in the sixth step, The zinc smelting method according to claim 2, wherein copper is concentrated in the obtained residue. 5. The zinc smelting method according to claim 1, wherein there is a step of adding a decoppering agent to the leachate in the sixth step to generate a copper-containing precipitate. 6. The zinc smelting method according to claim 2, wherein there is a step of adding a decoppering agent to the leachate in the sixth step to generate a copper-containing precipitate.