阅读说明：本技术 锌精矿冶炼装置和锌精矿冶炼方法 (Zinc concentrate smelting device and zinc concentrate smelting method ) 是由 许良 宋言 黎敏 吴卫国 彭思尧 张阁 陈学刚 戴江洪 于 2021-09-08 设计创作，主要内容包括：本发明提供了一种锌精矿冶炼装置和锌精矿冶炼方法。该装置包括：熔炼装置、熔渣检测单元、碳基还原剂供应装置、烟化装置和收尘装置,熔炼装置设置有第一进料口、探渣取样口、富氧空气侧吹喷枪、第一含锌烟气出口和高锌渣排放口；熔渣检测单元用于检测高锌渣中二价铁的含量；碳基还原剂供应装置设置有碳基还原剂供应口,碳基还原剂供应口与第一进料口连通,碳基还原剂供应装置与熔渣检测单元连锁,当高锌渣中二价铁的含量低于预定值时,开启碳基还原剂供应装置；烟化装置设置有第二进料口、粉煤喷枪、第二含锌烟气出口和放渣口,第二进料口与高锌渣排放口连通；收尘装置设置有收尘口,收尘口分别与第一含锌烟气出口和第二含锌烟气出口连通。(The invention provides a zinc concentrate smelting device and a zinc concentrate smelting method. The device includes: the device comprises a smelting device, a slag detection unit, a carbon-based reducing agent supply device, a fuming device and a dust collecting device, wherein the smelting device is provided with a first feed inlet, a slag detection sampling port, an oxygen-enriched air side-blowing spray gun, a first zinc-containing flue gas outlet and a high zinc slag discharge port; the slag detection unit is used for detecting the content of ferrous iron in the high-zinc slag; the carbon-based reducing agent supply device is provided with a carbon-based reducing agent supply port, the carbon-based reducing agent supply port is communicated with the first feed port, the carbon-based reducing agent supply device is interlocked with the slag detection unit, and the carbon-based reducing agent supply device is started when the content of ferrous iron in the high zinc slag is lower than a preset value; the fuming device is provided with a second feeding hole, a pulverized coal spray gun, a second zinc-containing flue gas outlet and a slag discharging hole, and the second feeding hole is communicated with the high zinc slag discharging hole; the dust collecting device is provided with a dust collecting port which is respectively communicated with the first zinc-containing flue gas outlet and the second zinc-containing flue gas outlet.)

1. A zinc concentrate smelting device is characterized by comprising:

the smelting device (10) is provided with a first feeding hole (101), a slag detection sampling hole (102), an oxygen-enriched air side-blowing spray gun (103), a first zinc-containing flue gas outlet (104) and a high zinc slag discharge hole (105);

the slag detection unit (20), the slag detection unit (20) is used for detecting the content of ferrous iron in the high zinc slag;

a carbon-based reducing agent supply device (30), wherein the carbon-based reducing agent supply device (30) is provided with a carbon-based reducing agent supply port, the carbon-based reducing agent supply port is communicated with the first feed port (101), the carbon-based reducing agent supply device (30) is interlocked with the slag detection unit (20), and when the content of ferrous iron in the high zinc slag is lower than a preset value, the carbon-based reducing agent supply device (30) is started;

the fuming device (40) is provided with a second feeding hole (401), a pulverized coal spray gun (402), a second zinc-containing flue gas outlet (403) and a slag discharging hole, and the second feeding hole (401) is communicated with the high zinc slag discharging hole (105); and

the device comprises a dust collecting device (50), wherein the dust collecting device (50) is provided with a dust collecting port and a zinc-containing dust outlet, and the dust collecting port is respectively communicated with the first zinc-containing flue gas outlet (104) and the second zinc-containing flue gas outlet (403).

2. The zinc concentrate smelting plant of claim 1, further comprising:

the acid leaching device (70) is provided with an acid liquor inlet (701), a zinc-containing dust inlet (702) and a zinc leaching liquid discharge port, and the zinc-containing dust inlet (702) is communicated with the zinc-containing dust outlet; and

the electrolytic device (80) is provided with a third feeding port and an electrolytic waste liquid discharge port, and the third feeding port is communicated with the zinc leachate discharge port through a zinc leachate conveying channel.

3. The zinc concentrate smelting plant according to claim 2, wherein the dust collecting device (50) is further provided with a sulfur-containing flue gas outlet (501), the zinc concentrate smelting plant further comprises an acid making device (90), the acid making device (90) is provided with an acidic flue gas inlet (901) and an acid liquor discharge port (902), the acidic flue gas inlet (901) is communicated with the sulfur-containing flue gas outlet, and the acid liquor discharge port (902) is communicated with the acid liquor inlet (701).

4. The zinc concentrate smelting plant according to any one of claims 1 to 3, characterized in that the slag detection unit (20), the slag detection unit (20) comprises:

the slag detection sampling device (21) is used for detecting and sampling molten high-zinc slag from the slag detection sampling port (102);

a sample crushing device (22), wherein the sample crushing device (22) is used for crushing the high zinc slag;

and the component detection device (23) is used for detecting the content of ferrous iron in the high zinc slag.

5. The zinc concentrate smelting plant according to claim 4, further comprising an oxygen-enriched air supply unit (60), the oxygen-enriched air supply unit (60) comprising:

an oxygen supply device (61), wherein the oxygen supply device (61) is provided with an oxygen supply port which is communicated with the oxygen-enriched air side-blowing lance (103) through an oxygen conveying channel;

an air supply device (62), the air supply device (62) being provided with a first air supply port which communicates with the oxygen-enriched air side-blowing lance (103) through a first air delivery channel; and

a first flow regulating device (63), the first flow regulating device (63) being for regulating the oxygen flow in the oxygen delivery channel;

a second flow regulating device (64), the second flow regulating device (64) for regulating the flow of air in the first air delivery passage.

6. The zinc concentrate smelting plant according to claim 5, wherein the air supply means (62) further includes a second air supply port communicating with the pulverized coal injection lance (402) via an air conveying conduit, and pulverized coal is injected into the fuming apparatus (40) by air conveyance through the pulverized coal injection lance (402).

7. Zinc concentrate smelting plant according to claim 1, characterized in that it further comprises a granulating device (11), said granulating device (11) being provided with a fourth feed opening and a pellet discharge opening, said pellet discharge opening being in communication with said first feed opening (101).

8. The zinc concentrate smelting plant according to claim 7, wherein the dust collecting port is in communication with the first zinciferous flue gas outlet (104) through a first zinciferous flue gas conveying passage and in communication with the second zinciferous flue gas outlet (403) through a second zinciferous flue gas conveying passage, the zinc concentrate smelting plant further comprising:

the first waste heat recovery device (12), the first waste heat recovery device (12) is arranged on the first zinc-containing flue gas conveying channel;

and the second waste heat recovery device (41), and the second waste heat recovery device (41) is arranged on the second zinc-containing flue gas conveying channel.

9. The zinc concentrate smelting method is characterized by comprising the following steps:

smelting zinc concentrate, flux, oxygen-enriched air and a carbon-based reducing agent to obtain first zinc-containing flue gas and high-zinc slag, wherein the weight ratio of the zinc concentrate to the flux to the carbon-based reducing agent is 100 (10-30) to (2-5) so as to ensure that ferrous iron in the high-zinc slag is not oxidized;

fuming the high-zinc slag to obtain second zinc-containing smoke and fuming slag;

and collecting dust of the first zinc-containing flue gas and the second zinc-containing flue gas to obtain zinc-containing dust.

10. The zinc concentrate smelting method according to claim 9, wherein the temperature in the smelting process is 1400-1500 ℃, and the concentration of the oxygen-enriched air is 65-90%.

11. The zinc concentrate smelting process according to claim 9, wherein the fuming treatment process is carried out at a temperature of 1250 ℃ to 1350 ℃.

12. The zinc concentrate smelting process according to any one of claims 9 to 11, further comprising:

directly carrying out acid leaching treatment on the zinc-containing dust by adopting an improved acid leaching system such as a hot acid leaching system to obtain a zinc-containing leaching solution and leaching residues; wherein the leaching residue can be used for recovering lead and silver, and the zinc-containing leaching solution is electrolyzed to obtain metal zinc.

13. The zinc concentrate smelting process according to claim 9, wherein the zinc concentrate is a zinc sulfide concentrate, and the flux is selected from one or more of the group consisting of a siliceous flux, a calcareous flux, and an iron flux;

the composition of the zinc concentrate comprises: 30-60% Zn, 25-35% S, 5-15% Fe, 3-10% SiO₂，1～5％CaO。

14. The zinc concentrate smelting method according to claim 9, wherein the content of ferrous iron in the high zinc slag is not less than 80 wt%.

Technical Field

The invention relates to the field of zinc concentrate smelting, in particular to a zinc concentrate smelting device and a zinc concentrate smelting method.

Background

Zinc has excellent physical and chemical properties, has wide application range and occupies an important position in national economy. The consumption of zinc is large, and is mainly consumed in the aspect of galvanization. From the market demand, the demand of zinc in our country market has increased greatly in the past decade. With the increase of environmental protection pressure and the further improvement of energy consumption requirements of zinc smelting industry, the existing production process needs to be continuously improved, the environmental pollution and the production energy consumption are reduced, and the zinc yield is increased.

At present, the production of zinc mainly comprises two processes of a fire method and a wet method. Blast furnaces, shaft pots and electric furnaces are the only existing pyrometallurgical zinc-smelting processes at present, but the energy consumption of these processes is generally high. Wherein, the blast furnace and the vertical tank have higher requirements on raw material components and complex material preparation process; the electric furnace needs to control the atmosphere and temperature in the furnace to prevent the large amount of reduction of iron; the zinc direct recovery rate of the three pyrometallurgical zinc smelting processes is lower, wherein the zinc content of blast furnace slag and electric furnace slag is high, and the total zinc recovery rate is low. Besides, the capacity of a single blast furnace can reach more than 5 ten thousand tons of zinc per year, and the capacity of a single series of vertical tanks and electric furnaces is only thousands of tons per year, so that the requirement of modern industrial mass production is difficult to meet.

In recent years, zinc smelting mainly adopts a wet process, zinc concentrate is fluidized and roasted to obtain roasted ore, and the roasted ore is finely ground and then is subjected to acid leaching. Acid leaching mainly comprises hot acid leaching and neutral (low acid) leaching. The hot acid leaching can cause iron in the roasting slag to enter the leaching solution to influence the subsequent electrolysis process, so that iron is required to be removed firstly, and the iron removal method mainly comprises a jarosite method, a goethite method, a spraying iron removal method, a hematite method and the like, wherein the hematite produced by the hematite method can be directly sold for iron making, and compared with other three methods, the method does not produce a large amount of waste slag and has great advantages. But the hematite method has long process, large steam consumption, high energy consumption and lower quality of the produced hematite. Therefore, at present, neutral (low acid) leaching is widely applied, the method can avoid leaching of iron, leachate can be electrolyzed after being simply purified, leaching slag with high zinc content (generally, 15% -18% of zinc content) can be generated by the method, the zinc leaching slag belongs to dangerous waste, relevant standards are strictly executed for treatment, the treatment and treatment cost is high, and the enterprise burden is greatly increased. Therefore, the zinc wet process has more procedures, complex process, huge investment and high energy consumption. Most importantly, a large amount of leaching slag, iron slag and the like are generated in the wet process, the yield of the leaching slag and the iron slag exceeds 50%, the slag belongs to dangerous waste, and needs to be subjected to harmless treatment, so that a large amount of energy consumption and new pollution are caused.

In view of the above problems, there is a need to provide a short-flow, low-energy-consumption, green and high-efficiency smelting method for zinc concentrate.

Disclosure of Invention

The invention mainly aims to provide a zinc concentrate smelting device and a zinc concentrate smelting method, and aims to solve the problems of long flow, poor environmental protection, high energy consumption, large investment, low recovery rate of valuable metals and the like in the conventional zinc concentrate smelting process.

In order to achieve the above object, an aspect of the present invention provides a zinc concentrate smelting apparatus, including: the device comprises a smelting device, a slag detection unit, a carbon-based reducing agent supply device, a fuming device and a dust collecting device, wherein the smelting device is provided with a first feed inlet, a slag detection sampling port, an oxygen-enriched air side-blowing spray gun, a first zinc-containing flue gas outlet and a high zinc slag discharge port; the slag detection unit is used for detecting the content of ferrous iron in the high-zinc slag; the carbon-based reducing agent supply device is provided with a carbon-based reducing agent supply port, the carbon-based reducing agent supply port is communicated with the first feed port, the carbon-based reducing agent supply device is interlocked with the slag detection unit, and the carbon-based reducing agent supply device is started when the content of ferrous iron in the high zinc slag is lower than a preset value; the fuming device is provided with a second feeding hole, a pulverized coal spray gun, a second zinc-containing flue gas outlet and a slag discharging hole, and the second feeding hole is communicated with the high zinc slag discharging hole; and the dust collecting device is provided with a dust collecting port and a zinc-containing dust outlet, and the dust collecting port is respectively communicated with the first zinc-containing flue gas outlet and the second zinc-containing flue gas outlet.

Further, the zinc concentrate smelting device also comprises: the device comprises an acid leaching device and an electrolysis device, wherein the acid leaching device is provided with an acid liquid inlet, a zinc-containing dust inlet and a zinc leaching liquid discharge port, and the zinc-containing dust inlet is communicated with a zinc-containing dust outlet; the electrolytic device is provided with a third feed port and an electrolytic waste liquid discharge port, and the third feed port is communicated with the zinc leachate discharge port through a zinc leachate conveying channel.

Furthermore, the dust collecting device is also provided with a sulfur-containing flue gas outlet, the zinc concentrate smelting device further comprises an acid making device, the acid making device is provided with an acidic flue gas inlet and an acid liquor discharge outlet, the acidic flue gas inlet is communicated with the sulfur-containing flue gas outlet, and the acid liquor discharge outlet is communicated with the acid liquor inlet.

Further, the slag detection unit includes: the slag detection sampling device is used for carrying out slag detection sampling on the molten high-zinc slag from a slag detection sampling port; the sample crushing device is used for crushing the high zinc slag; the component detection device is used for detecting the content of ferrous iron in the high-zinc slag.

Further, the zinc concentrate smelting device also comprises an oxygen-enriched air supply unit, and the oxygen-enriched air supply unit comprises: the oxygen supply device is provided with an oxygen supply port which is communicated with the oxygen-enriched air side-blowing spray gun through an oxygen conveying channel; the air supply device is provided with a first air supply port, and the first air supply port is communicated with the oxygen-enriched air side-blowing spray gun through a first air conveying channel; the first flow regulating device is used for regulating the oxygen flow in the oxygen conveying channel; the second flow regulating device is used for regulating the flow of air in the first air conveying channel.

Furthermore, the air supply device also comprises a second air supply port, the second air supply port is communicated with the pulverized coal spray gun through an air conveying pipeline, and the pulverized coal is conveyed by the air and sprayed into the fuming device through the pulverized coal spray gun.

Further, the zinc concentrate smelting device further comprises a granulating device, the granulating device is provided with a fourth feeding hole and a granular material discharging hole, and the granular material discharging hole is communicated with the first feeding hole.

Further, the dust collection port is communicated with the first zinc-containing flue gas outlet through a first zinc-containing flue gas conveying channel, and is communicated with the second zinc-containing flue gas outlet through a second zinc-containing flue gas conveying channel, and the zinc concentrate smelting device further comprises: the device comprises a first waste heat recovery device and a second waste heat recovery device, wherein the first waste heat recovery device is arranged on a first zinc-containing flue gas conveying channel, and the second waste heat recovery device is arranged on a second zinc-containing flue gas conveying channel.

The second aspect of the present application also provides a zinc concentrate smelting method, which includes: smelting zinc concentrate, flux, oxygen-enriched air and a carbon-based reducing agent to obtain first zinc-containing flue gas and high-zinc slag, wherein the weight ratio of the zinc concentrate to the flux to the carbon-based reducing agent is 100 (10-30) to (2-5) so as to ensure that ferrous iron in the high-zinc slag is not oxidized; fuming the high-zinc slag to obtain second zinc-containing smoke and fuming slag; and collecting dust of the first zinc-containing flue gas and the second zinc-containing flue gas to obtain zinc-containing dust.

Further, the temperature in the smelting process is 1400-1500 ℃, and the concentration of the oxygen-enriched air is 65-90%.

Further, the temperature of the fuming treatment process is 1250-1350 ℃.

Further, the zinc concentrate smelting method also comprises the following steps: directly carrying out acid leaching treatment on the zinc-containing dust by adopting an improved acid leaching system such as a hot acid leaching system to obtain a zinc-containing leaching solution and leaching residues; wherein the leaching residue can be used for recovering lead and silver, and the zinc-containing leaching solution is electrolyzed to obtain metal zinc.

Further, the zinc concentrate is zinc sulfide concentrate, and the flux is selected from one or more of the group consisting of siliceous flux, calcareous flux and ferrous flux; composition of zinc concentrateThe method comprises the following steps: 30-60% Zn, 25-35% S, 5-15% Fe, 3-10% SiO₂，1～5％CaO。

Furthermore, the content of ferrous iron in the high zinc slag is more than or equal to 80 wt%.

By applying the technical scheme of the invention, the zinc element in the zinc concentrate can be recovered in the flue gas in the form of zinc-containing smoke dust and directly sent to the improved hot acid leaching system, and simultaneously, the iron element completely enters the fuming slag (can not enter the flue gas), thereby realizing the complete separation of the zinc element and the iron element. In the process of leaching the zinc-containing smoke dust by the wet method, because the obtained zinc-containing smoke dust is not interfered by iron element, the working procedures of hot acid leaching and the like can be directly adopted without the iron removal working procedure, so that the iron removal working procedure is reduced. Because no iron element exists, a large amount of waste residues are not generated in the hot acid leaching process, and further, the pyrogenic process treatment procedure of the leached residues is not increased like the traditional process. In conclusion, the technical scheme of the invention has the characteristics of short flow, low energy consumption, good environmental protection, high efficiency and the like.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 shows a schematic structural view of a zinc concentrate smelting unit according to an exemplary embodiment of the present invention;

fig. 2 is a schematic structural view illustrating a zinc concentrate smelting unit according to a preferred embodiment of the present invention;

fig. 3 shows a process flow diagram of a zinc concentrate smelting method provided according to a preferred embodiment of the present invention.

Wherein the figures include the following reference numerals:

10. a smelting device; 11. a granulation device; 101. a first feed port; 102. a slag detecting sampling port; 103. oxygen-enriched air side-blown spray gun; 104. a first zinc-containing flue gas outlet; 105. a high zinc slag discharge port; 12. a first waste heat recovery device; 20. a slag detection unit; 21. a slag detecting and sampling device; 22. a sample disruption device; 23. a component detection device; 30. a carbon-based reductant supply; 40. a fuming device; 41. a second waste heat recovery device; 401. a second feed port; 402. a pulverized coal spray gun; 403. a second zinc-containing flue gas outlet; 50. a dust collecting device; 501. a sulfur-containing flue gas outlet; 60. an oxygen-enriched air supply unit; 61. an oxygen supply device; 62. an air supply device; 63. a first flow regulating device; 64. a second flow regulating device; 70. a pickling device; 701. an acid liquor inlet; 702. an inlet for zinc-containing dust; 80. an electrolysis device; 90. an acid making device; 901. an acidic flue gas inlet; 902. an acid liquor discharge port.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail with reference to examples.

As described in the background art, the existing zinc concentrate smelting process has the problems of low separation rate of zinc element and iron element and low recovery rate of the zinc element. In order to solve the above technical problems, the present application provides a zinc concentrate smelting apparatus, as shown in fig. 1 and 2, comprising: the device comprises a smelting device 10, a slag detection unit 20, a carbon-based reducing agent supply device 30, a fuming device 40 and a dust collecting device 50. The smelting device 10 is provided with a first feeding hole 101, a slag detecting sampling hole 102, an oxygen-enriched air side-blowing spray gun 103, a first zinc-containing flue gas outlet 104 and a high zinc slag discharge hole 105; the slag detection unit 20 is used for detecting the content of ferrous iron in the high zinc slag; the carbon-based reducing agent supply device 30 is provided with a carbon-based reducing agent supply port, the carbon-based reducing agent supply port is communicated with the first feed port 101, the carbon-based reducing agent supply device 30 is interlocked with the slag detection unit 20, and when the content of ferrous iron in the high zinc slag is lower than a preset value, the carbon-based reducing agent supply device 30 is started; the fuming device 40 is provided with a second feeding hole 401, a pulverized coal spray gun 402, a second zinc-containing flue gas outlet 403 and a slag discharging hole, wherein the second feeding hole 401 is communicated with the high zinc slag discharging hole 105; and the dust collecting device 50 is provided with a dust collecting port and a zinc-containing dust outlet, and the dust collecting port is respectively communicated with the first zinc-containing flue gas outlet 104 and the second zinc-containing flue gas outlet 403.

Through carbon-based reducing agent supply device 30 and slag detection unit 20 linked with it, can be through the linkage effect control carbon-based reducing agent's of the two addition volume to make the smelting process remain under weak reducing atmosphere all the time, this can be with zinc element in the zinc concentrate in the form of zinc-containing smoke and dust in the flue gas recovery, the ferrous iron in the zinc concentrate is not oxidized simultaneously, but all gets into fuming slag, thereby has realized the complete separation of zinc element and iron element.

It should be noted that the predetermined value of the content of the ferrous iron in the high zinc slag refers to the content of the ferrous iron in the zinc concentrate.

Therefore, the zinc concentrate smelting device provided by the application can be used for omitting an iron removal process due to no interference of iron elements in the subsequent process of leaching zinc-containing smoke dust by a wet method. Meanwhile, because no iron element exists, a large amount of waste residues can not be generated in the acid leaching process, so that the post-treatment process of the leached residues is omitted. In conclusion, the zinc concentrate smelting device can completely separate the iron element from the zinc element, improve the recovery rate of the zinc element and the iron element, shorten the flow of the subsequent extraction process of the zinc element and the iron element, reduce energy consumption, and improve the environmental protection performance and the separation efficiency of the process.

In a preferred embodiment, the zinc concentrate smelting unit further comprises: the device comprises an acid leaching device 70 and an electrolysis device 80, wherein the acid leaching device 70 is provided with an acid liquor inlet 701, a zinc-containing dust inlet 702 and a zinc leaching liquid discharge port, and the zinc-containing dust inlet is communicated with a zinc-containing dust outlet; and the electrolytic device 80 is provided with a third feed port and an electrolytic waste liquid discharge port, and the third feed port is communicated with the zinc leachate discharge port through a zinc leachate conveying channel. The zinc-containing dust and the acid liquor can be leached by the acid leaching device 70 to prepare a zinc leaching solution and lead silver slag. Then zinc element in the zinc leachate is converted into metal zinc through an electrolysis device 80, and valuable metals such as lead, silver, indium, germanium and the like are comprehensively recovered. The smelting device 10 can separate zinc and iron, a large amount of zinc elements form dust with the content of more than 98%, and acid leaching can be carried out without ore grinding, so that the process flow is greatly shortened, and the cost is reduced. The smelting device 10 provided by the application can meet the production of 10-30 ten thousand tons/year and other scales.

In a preferred embodiment, the dust collecting device 50 is further provided with a sulfur-containing flue gas outlet 501, the zinc concentrate smelting device further comprises an acid making device 90, the acid making device 90 is provided with an acidic flue gas inlet 901 and an acid liquor discharge outlet 902, and the acidic flue gas inlet 901 is communicated with the sulfur-containing flue gas outlet. The acid making device 90 is provided with an acid flue gas inlet 901 and an acid liquor discharge port 902, wherein the acid flue gas inlet 901 is communicated with a sulfur-containing flue gas outlet, and the acid liquor discharge port 902 is communicated with the acid liquor inlet 701. Because the sulfur content in the first zinc-containing flue gas is higher, the sulfur-containing flue gas is converted into acid liquor in the acid making device 90 so as to supplement the acid liquor to the acid leaching device 70, thereby being beneficial to saving the smelting cost.

The slag detection unit 20 can detect the content of divalent zinc in high-zinc slag discharged from the smelting device 10, so that the reducing atmosphere in the smelting process can be well controlled. In a preferred embodiment, the slag detection unit 20 includes: a slag detecting and sampling device 21, a sample crushing device 22 and a component detecting device 23. The slag detecting and sampling device 21 is used for detecting and sampling molten high-zinc slag from a slag detecting and sampling port 102 arranged on the smelting device; the sample crushing device 22 is used for crushing the high zinc slag; the component detection device 23 is used for detecting the content of ferrous iron in the high zinc slag.

In order to facilitate the input of the oxygen-enriched air while controlling the amount of oxygen to be introduced according to the atmosphere of the reaction system in the smelting unit 10, in a preferred embodiment, the zinc concentrate smelting unit further includes an oxygen-enriched air supply unit 60, and the oxygen-enriched air supply unit 60 includes: an oxygen supply device 61, an air supply device 62, a first flow rate adjustment device 63, and a second flow rate adjustment device 64. The oxygen supply device 61 is provided with an oxygen supply port which is communicated with the oxygen-enriched air side-blowing lance 103 through an oxygen delivery channel; the air supply device 62 is provided with a first air supply port which is communicated with the oxygen-enriched air side-blowing lance 103 through a first air delivery passage; the first flow regulating device 63 is used for regulating the oxygen flow in the oxygen delivery channel; the second flow regulating device 64 is used to regulate the flow of air in the first air delivery passage. The four devices are beneficial to further improving the oxidation rate of the zinc element in the smelting device 10 and improving the effective separation rate of the zinc element and other valuable metals.

In order to increase the contact area of the fuel (pulverized coal, coke, etc.) with other materials during the smelting process and thereby make it more reactive, in a preferred embodiment, the air supply 62 further includes a second air supply port that communicates with the pulverized coal injection lance 402 via an air delivery conduit through which pulverized coal is injected into the fuming apparatus 40 via the pulverized coal injection lance 402.

In order to improve the mixing uniformity of the zinc concentrate and the flux and further improve the extraction rate of the zinc element, it is preferable that the zinc concentrate smelting device further comprises a granulating device 11, and the granulating device 11 is provided with a fourth feeding hole and a granule discharging hole, and the granule discharging hole is communicated with the first feeding hole 101.

In order to reduce the energy consumption loss of the whole smelting device, in a preferred embodiment, the dust collecting port is communicated with the first zinciferous flue gas outlet 104 through a first zinciferous flue gas conveying channel and is communicated with the second zinciferous flue gas outlet through a second zinciferous flue gas conveying channel, and the zinc concentrate smelting device further comprises: the first waste heat recovery device 12 and the second waste heat recovery device 41 are arranged, and the first waste heat recovery device 12 is arranged on the first zinc-containing flue gas conveying channel; the second waste heat recovery device 41 is arranged on the second zinc-containing flue gas conveying channel.

Another aspect of the present application also provides a zinc concentrate smelting method, as shown in fig. 3, the zinc concentrate smelting method including: smelting zinc concentrate, flux, oxygen-enriched air and a carbon-based reducing agent to obtain first zinc-containing flue gas and high-zinc slag, wherein the weight ratio of the zinc concentrate to the flux to the carbon-based reducing agent is 100 (10-30) to (2-5) so as to ensure that ferrous iron in the high-zinc slag is not oxidized; fuming the high-zinc slag to obtain second zinc-containing smoke and fuming slag; and collecting dust of the first zinc-containing flue gas and the second zinc-containing flue gas to obtain zinc-containing dust.

The weight ratio of the zinc concentrate, the flux and the carbon-based reducing agent is limited in the range, so that the whole smelting process can be ensured to be in a weak reducing atmosphere, and ferrous iron in the high zinc slag can not be oxidized. By the smelting method, the zinc element in the zinc concentrate can be recovered in the smoke in the form of zinc-containing smoke dust, and simultaneously, the iron element completely enters the fuming furnace slag, so that the zinc element and the iron element are completely separated. Therefore, in the subsequent process of leaching the zinc-containing smoke dust by the wet method, the iron removal process is omitted because no iron element is interfered. Meanwhile, because no iron element exists, a large amount of waste residues can not be generated in the acid leaching process, so that the post-treatment process of the leached residues is omitted. In conclusion, the zinc concentrate smelting device can completely separate the iron element from the zinc element, improve the recovery rate of the zinc element and the iron element, shorten the flow of the subsequent extraction process of the zinc element and the iron element, reduce energy consumption, and improve the environmental protection performance and the separation efficiency of the process.

The zinc concentrate can be subjected to oxidative desulfurization through the smelting process, and meanwhile, the zinc concentrate can be separated from iron elements in the zinc concentrate. In a preferred embodiment, the temperature of the smelting process is 1400-1500 ℃, and the concentration of the oxygen-enriched air is 65-90%. The temperature in the smelting process and the concentration of the oxygen-enriched air are limited in the range, so that the oxidation desulfurization degree of the zinc concentrate is further improved, and the recovery rate of the zinc element is further improved.

The fuming treatment process can transfer the zinc element in the high-zinc slag to the second zinc-containing flue gas. In a preferred embodiment, the temperature of the fuming process is 1250 ℃ to 1350 ℃. Compared with other temperatures and time, the temperature and the time of the fuming treatment process are limited in the range, so that the fuming rate of the zinc element in the high-zinc slag is further improved, and the recovery rate of the zinc element is further improved.

Carbon-based reducing agents useful herein include, but are not limited to, coal fines, char, and the like.

In a preferred embodiment, the zinc concentrate smelting method further comprises: directly carrying out acid leaching treatment on the zinc-containing dust by adopting an improved acid leaching system such as a hot acid leaching system to obtain a zinc-containing leaching solution and leaching residues; wherein the leaching residue can be used for recovering lead and silver, and the zinc-containing leaching solution is electrolyzed to obtain metal zinc. The zinc-containing dust and the acid liquor can be leached through acid leaching treatment to prepare a zinc leachate and lead-silver residues. Then zinc element in the zinc leachate is converted into metal zinc through the electrolysis process, and valuable metals such as lead, silver, indium, germanium and the like are comprehensively recovered. The smelting method can separate zinc and iron elements, a large amount of zinc (more than 98 percent) forms dust, and acid leaching treatment can be carried out without grinding ore, so that the process flow is greatly shortened, and the cost is reduced. The smelting method provided by the application can meet the production of 10-30 ten thousand tons per year and other various scales.

In order to further increase the recovery of zinc, the content of zinc in the fuming slag is preferably less than 1%.

In a preferred embodiment, the zinc concentrate smelting process further comprises the step of recovering waste heat from the first zinc containing flue gas and the second zinc containing flue gas before the dust collecting step. The waste heat recovery step is beneficial to recovering the heat in the first zinc-containing flue gas and the second zinc-containing flue gas, and simultaneously, the energy loss in the whole process is reduced.

In the zinc concentrate smelting method, the zinc concentrate can adopt zinc sulfide concentrate, and the fluxing agent comprises one or more of the group consisting of but not limited to siliceous fluxing agent, calcareous fluxing agent and ferrous fluxing agent. In a preferred embodiment, the zinc concentrate is a zinc sulphide concentrate, the flux being selected from one or more of the group consisting of a siliceous flux, a calcareous flux and a ferrous flux; the composition of the zinc concentrate comprises: 30-60% Zn, 25-35% S, 5-15% Fe, 3-10% SiO₂，1～5％CaO。

In a preferred embodiment, the content of ferrous iron in the high zinc slag is more than or equal to 80 percent.

The present application is described in further detail below with reference to specific examples, which should not be construed as limiting the scope of the invention as claimed.

The zinc concentrate used in the examples included: zn, 51%; s, 33%; 10% of Fe; SiO 2₂，6.5％；CaO，3％。

Example 1

Zinc concentrate and SiO₂And CaO in a weight ratio of 20:2:1Proportioning and granulating, adding the mixture from a first feeding hole 101 of a smelting device 10 (side-blown smelting furnace), spraying oxygen-enriched air into a molten pool by an oxygen-enriched air side-blown spray gun 103 of the smelting device 10 (side-blown smelting furnace), and then carrying out oxidation smelting on zinc concentrate and the oxygen-enriched air to obtain smoke and zinc-containing smelting slag. Detecting the content of divalent bodies in the slag by using a slag detection unit 20, and adding a proper amount of carbonaceous reducing agent (coal) by using a carbon-based reducing agent supply device 30 according to the content of divalent iron in the slag, wherein the weight ratio of the added amount of the carbonaceous reducing agent to zinc concentrate is (2-5): 100. SO in flue gas of smelting device 10 (side-blown smelting furnace)₂The content is more than 15%, the high-sulfur flue gas and the zinc-containing dust are obtained after the temperature reduction of the first waste heat recovery device 12 (waste heat boiler) and the dust collection of the dust collection device 50, wherein the high-sulfur flue gas is sent to an acid making device 90 for making acid. The slag form of the obtained zinc-containing smelting slag is ZnO-FeO-SiO₂Type, ZnO-FeO-SiO₂CaO type, ZnO-FeO-SiO₂CaO-ZnO type, oxygen concentration in oxygen-enriched air is 65%, and the melting temperature of the melting device 10 (side-blown melting furnace) is 1400 ℃.

The zinc-containing smelting slag is conveyed into a fuming device 40 (fuming furnace) through a heat-preservation chute to be subjected to fuming treatment, so that smoke and fuming slag are obtained, the smelting temperature of the fuming device 40 (fuming furnace) is 1250 ℃, and the oxygen concentration is 21%. The flue gas is cooled by a second waste heat recovery device 41 (waste heat boiler), and dust is collected by a dust collection device 50 to obtain zinc-containing dust. The zinc dust produced by the smelting device 10 (side-blown smelting furnace) and the fuming device 40 (fuming furnace) is directly sent to the modified acid leaching device 70 for leaching. The obtained lead-silver slag can be sent to a lead system to recover lead and silver, and valuable metals such as indium, germanium and the like are recovered in the leaching process. And purifying and electrolyzing the leaching solution to produce cathode zinc.

Example 2

The difference from example 1 is that: the melting temperature of the fuming apparatus 40 (fuming furnace) was 1300 ℃.

Example 3

The difference from example 1 is that: the melting temperature of the fuming apparatus 40 (fuming furnace) was 1350 ℃.

Example 4

The difference from example 3 is that: the temperature in the smelting process is 1450 ℃, and the oxygen concentration in the oxygen-enriched air is 75 percent.

Example 5

The difference from example 3 is that: the temperature in the smelting process is 1500 ℃, and the oxygen concentration in the oxygen-enriched air is 90%.

The contents of zinc element and iron element and the recovery rate of zinc element in the fuming slag in the smelting process of zinc concentrate in examples 1 to 5 are shown in table 1.

TABLE 1

As can be seen from comparative examples 1 to 3, limiting the temperature of the fuming furnace to the range preferable in the present application facilitates the separation of zinc and iron, and further improves the recovery rate of metallic zinc.

In comparative examples 3 to 5, it is understood that limiting the temperature of the melting process within the preferred range of protection of the present application facilitates the separation of zinc and iron, and further improves the recovery rate of metallic zinc.

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects: through the zinc concentrate smelting device provided by the application, the iron removal process is omitted due to no interference of iron elements in the process of leaching zinc-containing smoke dust by a subsequent wet method. Meanwhile, because no iron element exists, a large amount of waste residues can not be generated in the acid leaching process, so that the subsequent treatment process of the leached residues is omitted. In conclusion, the zinc concentrate smelting device can completely separate the iron element from the zinc element, and improve the recovery rate of the zinc element.

It is noted that the terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the application described herein are, for example, capable of operation in sequences other than those described or illustrated herein.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.