阅读说明：本技术 高铅高铜高铁的锌精矿的焙烧处理方法 (Roasting treatment method of zinc concentrate with high lead, copper and iron contents ) 是由 苟海鹏 许良 陈学刚 周钢 彭思尧 裴忠冶 吴卫国 陈宋璇 王建铭 王忠实 于 2021-09-17 设计创作，主要内容包括：本发明提供了一种高铅高铜高铁的锌精矿的焙烧处理方法。处理方法,其包括以下步骤：步骤S1,将高铅高铜高铁的锌精矿与粘结剂混合并制粒,然后干燥,得到锌精矿粒料；步骤S2,将锌精矿粒料进行加入沸腾焙烧炉或流化床内进行氧化焙烧处理,得到焙烧产物；步骤S3,将焙烧产物送入氢气还原炉进行选择性还原,以将其中的铁酸锌还原为ZnO和Fe-(3)O-(4),得到还原产物。本发明有效解决了高铅高铜高铁的锌精矿的焙烧粘结问题,降低焙烧过程中产生的烟尘量,提高氧化焙烧工序的床能力,同时有效将焙烧产物中的铁酸锌转化为可溶性锌,使焙烧产物满足后续湿法浸出工艺的要求。(The invention provides a roasting treatment method of zinc concentrate with high lead, copper and iron contents. A method of treatment comprising the steps of: step S1, mixing the zinc concentrate with high lead, high copper and high iron with a binder, granulating, and drying to obtain zinc concentrate granules; step S2, adding the zinc concentrate granules into a fluidized bed roaster or a fluidized bed for oxidizing roasting treatment to obtain roasted products; step S3, the roasted product is sent into a hydrogen reduction furnace for selective reduction so as to reduce the zinc ferrite into ZnO and Fe 3 O 4 And obtaining a reduction product. The invention effectively solves the roasting bonding problem of the zinc concentrate with high lead, high copper and high iron, reduces the smoke amount generated in the roasting process, and improves the oxidizing roasting processThe bed capacity of the method, and simultaneously effectively converting the zinc ferrite in the roasted product into soluble zinc, so that the roasted product meets the requirements of the subsequent wet leaching process.)

1. The roasting treatment method of the zinc concentrate with high lead, copper and iron is characterized by comprising the following steps:

step S1, mixing the zinc concentrate with high lead, copper and iron with a binder, granulating, and drying to obtain zinc concentrate granules;

step S2, adding the zinc concentrate granules into a fluidized bed roaster or a fluidized bed for oxidizing roasting treatment to obtain roasted products;

step S3, feeding the roasted product into hydrogen reductionThe primary furnace is selectively reduced to reduce the zinc ferrite into ZnO and Fe₃O₄And obtaining a reduction product.

2. The method according to claim 1, wherein the zinc concentrate with high lead, copper and iron content is more than or equal to 2.5 wt%, and/or the copper content is more than or equal to 1.5 wt%, and/or the iron content is more than or equal to 14 wt%.

3. The method according to claim 1 or 2, wherein in the step S3, the temperature of the selective reduction is 500-600 ℃, and the reduction time is 60-120 min;

preferably, the atmosphere of the selective reduction is hydrogen, or a mixed gas of hydrogen and nitrogen, or a mixed gas of hydrogen and an inert gas, and the inert gas is one or more of He, Ne, Ar, Kr and Xe.

4. The method according to any one of claims 1 to 3, wherein the binder is one or more of smoke dust returned in the oxidizing roasting treatment process, dilute sulfuric acid with the mass concentration of 10-40%, zinc sulfate, bentonite and water;

preferably, the dosage of the binder is (8.5-9.5): (1.5-0.5) of the weight of the zinc concentrate with high lead, high copper and high iron;

preferably, the particle size of the zinc concentrate granules is 0.5-5 mm;

preferably, the water content of the zinc concentrate pellet is less than 1 wt%.

5. The method according to any one of claims 1 to 4, wherein in the step S2, the temperature of the oxidative roasting treatment is 900 to 1100 ℃, and the roasting time is 3 to 5 hours.

6. The method according to claim 5, wherein during the oxidative roasting treatment, the roasting atmosphere is an oxidative atmosphere, preferably air or oxygen-enriched air.

7. The method as claimed in claim 6, wherein the air or the oxygen-enriched air is blown into the fluidized bed roaster or the fluidized bed during the oxidizing roasting treatment, the blowing linear velocity is more than or equal to 2m/s, and the produced smoke rate is less than 12%.

8. Method according to claim 7, characterized in that the bed capacity of the fluidized bed and the fluidized bed of the fluidized bed are greater than 20t/m²D, the S content of the calcined product is less than 1 wt%.

9. The method of claim 1, wherein the shape of the ebullient roaster and the fluidized bed is circular, oval, or rectangular;

preferably, the granulating step adopts disc granulation or cylinder granulation.

10. The method of claim 1, wherein after obtaining the reduction product, the method further comprises:

and step S4, sequentially carrying out wet leaching and electrolytic extraction on the reduction product to obtain metal zinc.

Technical Field

The invention relates to the technical field of metallurgy, in particular to a roasting treatment method of zinc concentrate with high lead, high copper and high iron.

Background

At present, zinc smelting mainly comprises the working procedures of fluidized roasting, leaching, purification, electrodeposition and the like by taking zinc sulfide concentrate as a raw material. With the gradual depletion of zinc concentrate resources with low iron, low lead and low copper, the zinc concentrate with high lead, high copper and high iron gradually becomes an important raw material for zinc smelting.

Patent CN108866321A discloses a fluidized bed roaster for treating high-copper high-lead zinc concentrate, which can improve the bed capacity of the fluidized bed roaster, reduce the S content in the roasted product and avoid sintering the high-lead high-copper zinc concentrate, but the fluidized bed roaster is not really put into industrial production all the time, and the bed capacity of the fluidized bed roaster is only 5.5-7.5 t/m at present²D. The root cause of the failure of the industrial implementation is that the granulation boiling roasting inevitably leads to the peroxidation of zinc concentrate, so that a large amount of zinc ferrite is generated in the roasted product, the proportion of soluble zinc in the roasted product is reduced, and the roasted product cannot be used for wet leaching. Although the calcine containing a large amount of zinc ferrite can be used for pyrometallurgical treatment, the smelting difficulty and cost of pyrometallurgical zinc smelting are greatly increased due to the high melting point of the zinc ferrite and the increase of the viscosity of smelting slag.

Patent CN10728445A discloses a method for extracting metallic zinc from sphalerite in vacuum, which comprises oxidizing and roasting the sphalerite in air atmosphere at 1050-1080 ℃ to generate calcine; and uniformly mixing the calcine and the metallic iron, distilling at the constant pressure of 10-30 Pa and the temperature of 1050-1200 ℃ for 20-60 min to obtain metallic zinc steam, and condensing to obtain metallic zinc. However, the obtained calcine and metallic iron need to be uniformly mixed and then heated to 1050-1200 ℃ again, heat generated in the roasting process is not fully utilized, and energy waste is caused.

Patent CN104004923B discloses a method for extracting zinc by combining roasting leaching and direct leaching of zinc sulfide concentrate, roasting the zinc sulfide concentrate, and performing neutral leaching on the roasted product at the temperature of 60-70 ℃ and the end point pH of 5.0-5.2; then carrying out hot acid leaching on the bottom flow, wherein the temperature is 80-90 ℃, and the end point acidity is 50-100 g/L; and finally, adding zinc sulfide concentrate into the supernatant, introducing oxygen with the concentration of more than 98%, controlling the temperature to be 145-155 ℃, the pressure to be 1100-1300 kPa and the end-point acidity to be 10-20 g/L, and leaching zinc and removing iron at the same time. However, the process requires multiple leaching under high temperature, high pressure and high purity oxygen conditions to separate zinc and iron elements, the process flow is long, and leaching equipment is easily corroded.

In a word, the high-lead high-copper zinc concentrate is seriously bonded in the roasting process, and the generated bonding product is settled at the bottom of a fluidized bed or a fluidized bed, so that a tuyere is easily blocked, the accumulation of materials is formed in the furnace, the furnace condition is seriously worsened, and finally the furnace is shut down for maintenance. Zinc ferrite is generated in the roasting process of the high-iron zinc concentrate, the content of soluble zinc in a roasted product is reduced, and a subsequent wet leaching process is influenced.

Disclosure of Invention

The invention mainly aims to provide a roasting treatment method of high-lead, high-copper and high-iron zinc concentrate, which aims to solve the roasting bonding problem of the high-lead, high-copper and high-iron zinc concentrate in the prior art and simultaneously improve the problem of low soluble zinc content in a roasted product so as to reduce the difficulty of a subsequent wet leaching process.

In order to achieve the above object, according to one aspect of the present invention, there is provided a roasting treatment method of zinc concentrate high in lead, copper and iron, comprising the steps of: step S1, the zinc concentrate with high lead, copper and iron is bondedMixing the agents, granulating and drying to obtain zinc concentrate granules; step S2, adding the zinc concentrate granules into a fluidized bed roaster or a fluidized bed for oxidizing roasting treatment to obtain roasted products; step S3, the roasted product is sent into a hydrogen reduction furnace for selective reduction so as to reduce the zinc ferrite into ZnO and Fe₃O₄And obtaining a reduction product.

Furthermore, in the zinc concentrate with high lead, copper and iron, the lead content is more than or equal to 2.5 wt%, and/or the copper content is more than or equal to 1.5 wt%, and/or the iron content is more than or equal to 14 wt%.

Further, in the step S3, the temperature of the selective reduction is 500-600 ℃, and the reduction time is 60-120 min; preferably, the atmosphere of the selective reduction is hydrogen, or a mixed gas of hydrogen and nitrogen, or a mixed gas of hydrogen and an inert gas, and the inert gas is one or more of He, Ne, Ar, Kr and Xe.

Further, the binder is one or more of smoke dust returned in the oxidizing roasting treatment process, dilute sulfuric acid with the mass concentration of 10-40%, zinc sulfate, bentonite and water; preferably, the dosage of the binder is (8.5-9.5): (1.5-0.5) of the weight of the zinc concentrate with high lead, high copper and high iron; preferably, the particle size of the zinc concentrate granules is 0.5-5 mm; preferably, the water content of the zinc concentrate pellet is less than 1 wt%.

Further, in step S2, the temperature of the oxidizing roasting treatment is 900-1100 ℃, and the roasting time is 3-5 h.

Further, in the oxidizing roasting treatment, the roasting atmosphere is an oxidizing atmosphere, and preferably air or oxygen-enriched air.

Furthermore, in the process of oxidizing roasting treatment, air or oxygen-enriched air is injected into the fluidized bed roasting furnace or the fluidized bed, the injection linear velocity is more than or equal to 2m/s, and the produced smoke dust rate is less than 12%.

Further, the bed capacity of the fluidized bed and the fluidized bed of the fluidized bed are more than 20t/m²D, the S content in the calcined product is less than 1% by weight.

Furthermore, the furnace types of the fluidized bed roaster and the fluidized bed are round, oval or rectangular; preferably, the granulating step uses disk granulation or cylinder granulation.

Further, after obtaining the reduction product, the method further comprises: and step S4, sequentially carrying out wet leaching and electrolytic extraction on the reduction product to obtain the metal zinc.

The roasting treatment method of the zinc concentrate with high lead, copper and iron effectively solves the roasting bonding problem, reduces the smoke dust amount generated in the roasting process, improves the bed capacity of the oxidizing roasting process, and effectively converts zinc ferrite in the roasted product into soluble zinc, so that the roasted product meets the requirements of the subsequent wet leaching process.

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 flow diagram of a roasting treatment method of zinc concentrate with high lead, copper and iron contents according to an embodiment of the present invention;

figure 2 shows a standard gibbs free energy change curve for the reaction of hydrogen with zinc iron spinel.

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 below with reference to the embodiments with reference to the attached drawings.

The invention provides a roasting treatment method of zinc concentrate with high lead, copper and iron, as shown in figure 1, comprising the following steps: step S1, mixing the zinc concentrate with high lead, high copper and high iron with a binder, granulating, and drying to obtain zinc concentrate granules; step S2, adding the zinc concentrate granules into a fluidized bed roaster or a fluidized bed for oxidizing roasting treatment to obtain roasted products; step S3, the roasted product is sent into a hydrogen reduction furnace for selective reduction so as to reduce the zinc ferrite into ZnO and Fe₃O₄And obtaining a reduction product.

The chemical compositions of the zinc concentrates of different grades are as follows:

TABLE 1

When the lead content or the copper content in the zinc concentrate is high, the zinc concentrate can generate low-melting-point components such as lead oxide, copper sulfate, lead silicate, cuprous oxide and the like in the roasting process, so that the materials are agglomerated, the flowability is extremely poor, the furnace condition is deteriorated, the discharging is not smooth, and finally the accident shutdown is caused. When the iron content in the zinc concentrate is high, zinc ferrite can be generated in the roasting process of the zinc concentrate, the zinc ferrite cannot react with sulfuric acid in the subsequent leaching process, so that the content of soluble zinc in the roasted product is reduced, and the leached slag obtained after leaching is difficult to be applied to secondary treatment by pyrometallurgy due to the high melting point of the zinc ferrite.

The invention improves the granularity of the materials entering the furnace by granulating and pelletizing before oxidizing roasting, effectively reduces the smoke dust rate in the roasting process and also improves the roasting bonding problem. Furthermore, the peroxidation of the zinc concentrate during the oxidizing roasting treatment leads to ZnS and FeS₂Can form a large amount of zinc-iron spinel (ZnFe)₂O₄) And the proportion of soluble zinc in the calcine is reduced. The most key point of the invention is that the roasted material is still at a certain temperature and is sent into a reduction furnace to be selectively reduced by hydrogen, the heat energy of the material is effectively utilized, the insoluble zinc in the roasted sand is converted into soluble zinc, and the soluble zinc is compared with FeO and Fe₃O₄Is difficult to react with dilute sulphuric acid, can reduce the Fe content in the leaching liquid in the subsequent reduction product leaching process, and is beneficial to further extracting the metal zinc in the wet process. Therefore, the invention reduces the zinc ferrite in the zinc ferrite into ZnO and Fe through hydrogen selective reduction₃O₄The method not only effectively improves the content of soluble zinc (the content of the soluble zinc in the reduction product accounts for more than 92 percent of the total zinc content), but also reduces the leaching of iron impurities in the subsequent leaching process, and effectively improves the leaching effect of zinc.

In addition, the present invention utilizes hydrogen reduction, as compared to other reducing atmospheres, such as carbon-containing reducing atmospheresHas the following advantages: the existence of residual carbon in the low-temperature reduction process can be avoided, and the product purity is higher; reduction of CO in pyrometallurgical processes₂Discharging of (3); when the reaction temperature is lower, the carbon reduction belongs to solid-solid reaction, the reaction rate is influenced by the reaction temperature and the contact area between reactants, the hydrogen reduction belongs to gas-solid reaction, the direct contact area of the reactants is larger than that of the solid-solid reaction, and the reaction rate is superior to that of the carbon reduction process under the low-temperature condition.

The roasting process provided by the invention is suitable for zinc concentrate with high lead, high copper and high iron, and can also be used for zinc concentrate with high lead, high copper and high iron which cannot be treated due to overhigh element, such as high lead zinc concentrate, high copper zinc concentrate or high iron zinc concentrate. Preferably, the lead content is more than or equal to 2.5 wt%, and/or the copper content is more than or equal to 1.5 wt%, and/or the iron content is more than or equal to 14 wt% in the zinc concentrate with high lead, high copper and high iron. In addition, the hydrogen reduction and wet zinc extraction process can also be used for other secondary wastes which contain iron and have high zinc content and are difficult to treat, such as zinc-containing smoke dust (the smoke dust contains a large amount of zinc ferrite) in a steel mill.

FIG. 2 is a standard Gibbs free energy change curve of selective reduction of zinc ferrite under different reaction temperature conditions in a hydrogen atmosphere. As can be seen from FIG. 2, when the reaction temperature is higher than 400 ℃, the zinc-iron spinel can be reduced by hydrogen to generate ZnO and Fe₃O₄(ii) a When the reaction temperature is higher than 600 ℃, the zinc-iron spinel can be reduced by hydrogen to generate ZnO and FeO. In combination with the influence of the reaction temperature on the reaction rate, in a preferred embodiment, the temperature of the selective reduction is 500-600 ℃, and the reduction time is 60-120 min. Can be fully reduced to form ZnO and Fe under the temperature condition₃O₄Meanwhile, the reaction efficiency is further improved. More preferably, the temperature of the selective reduction is 550 ℃. The production of FeO is reduced as much as possible in the reaction process, so that the iron removal cost of the subsequent leachate can be reduced, the reaction temperature is preferably not higher, and the reaction time is not too long.

Preferably, the atmosphere of the selective reduction is hydrogen, or a mixed gas of hydrogen and nitrogen, or a mixed gas of hydrogen and an inert gas, and the inert gas is one or more of He, Ne, Ar, Kr and Xe.

In a preferred embodiment, the binder is one or more of smoke returned in the oxidizing roasting process, dilute sulfuric acid with the mass concentration of 10-40%, zinc sulfate, bentonite and water. The adoption of the binders is beneficial to granulation on one hand, and on the other hand, new impurities are not introduced to influence the subsequent roasting and reduction processes. Preferably, the dosage of the binder is (8.5-9.5): (1.5-0.5) of the weight of the zinc concentrate with high lead, high copper and high iron; more preferably, the particle size of the zinc concentrate granules is 0.5-5 mm; further preferably, the water content of the zinc concentrate granules is less than 1 wt%.

In the oxidizing/baking treatment process, in order to further improve the oxidizing/baking effect, in a preferred embodiment, in the step S2, the temperature of the oxidizing/baking treatment is 900 to 1100 ℃, and the baking time is 3 to 5 hours. Preferably, during the oxidizing roasting treatment, the roasting atmosphere is an oxidizing atmosphere, preferably air or oxygen-enriched air.

As mentioned above, the invention effectively reduces the smoke rate in the roasting process and also improves the roasting caking problem because the zinc concentrate is granulated in advance. In order to ensure that the material is in a boiling state in a fluidized bed or a fluidized bed, the blowing rate of a tuyere needs to be increased, the specific blowing rate can be adjusted according to the particle size and the distribution of the material, and can also be adjusted according to the specific bed capacity of the fluidized bed and the fluidized bed, in a preferred embodiment, in the process of oxidizing roasting treatment, air or oxygen-enriched air (the volume content of oxygen is more than 21 percent) is blown into a fluidized bed or a fluidized bed, the blowing linear velocity is more than or equal to 2m/s, and the produced smoke rate is less than 12 percent. More preferably, the bed capacity of the roaster and the fluidized bed is more than 20t/m²D. Due to the improvement of the blowing air quantity, the removal rate of sulfides in the materials in the whole roasting process is obviously improved, and the S content in the roasted product is lower than 1 wt%. The high desulfurization rate inevitably brings about peroxidation of materials, and the invention is based on hydrogen reduction, thereby effectively solving the problem of reduction of soluble zinc caused by peroxidation, which is already mentioned above.

In the specific operation process, roasting smoke and roasting smoke dust are also generated in the oxidizing roasting treatment process, the roasting smoke dust can be returned to be used as a binder, and the roasting smoke dust can be used for preparing acid.

The above-mentioned fluidized bed roaster and fluidized bed may be of conventional furnace type, and preferably, the furnace type of the fluidized bed roaster and fluidized bed is circular, oval or rectangular. The above granulation process may be carried out in a conventional granulation form, such as disc granulation or drum granulation.

Through the granulation, oxidizing roasting and hydrogen reduction, the content of soluble zinc in the zinc concentrate is greatly increased and can reach more than 92% of the total zinc content, and iron is also converted into ferroferric oxide which is difficult to leach, so that the subsequent zinc leaching is greatly promoted, the zinc leaching is facilitated, and the iron leaching is inhibited. In a preferred embodiment, after obtaining the reduction product, the method further includes step S4: and sequentially carrying out wet leaching and electrolytic extraction on the reduction product to obtain the metal zinc. The specific wet leaching and electrolysis processes are conventional in the art and are not described in detail herein. Fe in the leaching slag generated in the wet leaching step is mainly Fe₃O₄The Fe element in the material can be further recovered through a magnetic separation or pyrometallurgical process.

In a word, the invention effectively solves the roasting bonding problem of the zinc concentrate with high lead, high copper and high iron, reduces the smoke dust amount generated in the roasting process, improves the bed capacity of the oxidizing roasting process, and effectively converts the zinc ferrite in the roasted product into soluble zinc, so that the roasted product meets the requirements of the subsequent wet leaching process. With the consumption of high-quality zinc concentrate resources, each zinc smelting plant will attach more importance to the complex and intractable zinc concentrate resources in the future, and the invention has wide application prospect in the future.

In addition, the invention further performs hydrogen reduction in the reduction furnace by utilizing the heat generated by oxidizing roasting, thereby saving more energy. The invention separates zinc and iron elements with high efficiency by carrying out peroxidation-selective reduction on zinc concentrate, greatly simplifies the process flow (a large amount of zinc ferrite is generated in the granulating, oxidizing and roasting process, and the zinc calcine is often suitable for the pyrometallurgical zinc refining processes (open-can zinc refining, vertical-can zinc refining, electric furnace zinc refining and the like) because the proportion of soluble zinc in the calcine is low. The zinc calcine containing zinc ferrite can also adopt a jarosite method or a goethite method to remove iron, but the problems of long process flow, complex iron removal process and the like exist.

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.

Example 1:

the contents of main elements in a high-lead, high-copper, high-iron and zinc concentrate are shown in the following table, wherein the contents of lead are 8.6%, copper are 3.2% and iron is 7.8%. Mixing the zinc concentrate with return dust (smoke dust returned in the oxidizing roasting treatment process) and dilute sulfuric acid (40 wt%) according to a mass ratio of 90:8:2, uniformly mixing, and granulating by using a disc granulator to ensure that the prepared granules meet the requirement of 0.5-5 mm, wherein the proportion of 1-2 mm granules is more than 75%. And drying the granulated material to ensure that the water content in the material is less than 1%.

At 10m²For example, the fluidized bed furnace can reach 24t/m²D, the feeding amount per hour is 10t, the roasting treatment is carried out at 960 ℃, the roasting time is 4h, the air blowing linear velocity is 2.3m/s, and the smoke dust output in the roasting process is 11.5%. The calcine produced by the fluidized bed furnace flows into a reduction furnace, and is selectively reduced at 550 ℃ under the condition of hydrogen, the reduction time is 90min, and the soluble zinc in the reduction slag accounts for 97 percent of the total mass of zinc. And (3) carrying out wet leaching (normal temperature and normal pressure leaching) on the reducing slag, wherein the mass ratio of zinc to iron in the leaching solution is 93:7, and electrolyzing and extracting the metal zinc after purifying the leaching solution.

TABLE 2 contents of main constituents of a high-lead, high-copper, high-iron and high-zinc concentrate

Element(s)	Zn	Pb	Cu	Fe	S
						Content (wt.)	50.2	8.6	3.2	7.8	30.1

Example 2:

the contents of main elements in a high-lead, high-copper, high-iron and zinc concentrate are shown in the following table, wherein the contents of lead are 3.5%, copper are 2.1% and iron is 14.2%. Mixing the zinc concentrate with zinc sulfate and water according to a mass ratio of 92:6:2, granulating by using a cylindrical granulator after uniformly mixing, and ensuring that the prepared granules meet 0.5-5 mm, wherein 2-3 mm granules account for more than 75%. And drying the granulated material to ensure that the water content in the material is less than 1%.

At 10m²For example, the fluidized bed furnace can reach 26t/m²D, the feeding amount per hour is 10.83t, the roasting treatment is carried out at 1050 ℃, the roasting time is 5h, the air blowing linear velocity is 2.5m/s, and the smoke dust output in the roasting process is 10.9%. The calcine produced by the fluidized bed furnace flows into a reduction furnace, and is selectively reduced at 600 ℃ under the condition of hydrogen for 120minThe soluble zinc in the reducing slag accounts for 99 percent of the total zinc mass. And (3) carrying out wet leaching (normal temperature and normal pressure leaching) on the reducing slag, wherein the mass ratio of zinc to iron in the leaching solution is 88:12, and electrolyzing and extracting the metal zinc after purifying the leaching solution.

TABLE 3 content of main constituents of a high-lead, high-copper, high-iron and high-zinc concentrate

Element(s)	Zn	Pb	Cu	Fe	S
						Content (wt.)	46.8	3.5	2.1	14.2	32.5

Example 3:

the contents of main elements in a high-lead, high-copper, high-iron and zinc concentrate are shown in the following table, wherein the contents of lead are 4.5%, copper are 2.5% and iron is 6.5%. Mixing the zinc concentrate with return dust (smoke dust returned in the oxidizing roasting treatment process) and dilute sulfuric acid (10 wt%) according to a mass ratio of 90:8:2, uniformly mixing, and granulating by using a disc granulator to ensure that the prepared granules meet the requirement of 0.5-5 mm, wherein the proportion of 3-4 mm granules is more than 75%. And drying the granulated material to ensure that the water content in the material is less than 1%.

At 10m²For example, the fluidized bed furnace can reach 30t/m²D, the feeding amount per hour is 12.5t, the roasting treatment is carried out at the temperature of 1000 ℃, the roasting time is 3h, the air blowing linear velocity is 2.6m/s, and the smoke dust output in the roasting process is 9.8 percent. The calcine produced by the fluidized bed furnace flows into a reduction furnace, selective reduction is carried out at 500 ℃ under the condition of hydrogen and nitrogen (the volume of the hydrogen accounts for 30 percent), the reduction time is 60min, and the soluble zinc in the reduction slag accounts for 92 percent of the total zinc mass. And (3) carrying out wet leaching (normal temperature and normal pressure leaching) on the reducing slag, wherein the mass ratio of zinc to iron in the leaching solution is 95:5, and electrolyzing and extracting the metal zinc after purifying the leaching solution.

TABLE 4 contents of main constituents of a high-lead, high-copper, high-iron and high-zinc concentrate

Element(s)	Zn	Pb	Cu	Fe	S
						Content (wt.)	52.3	4.5	2.5	8.0	32.1

Example 4

The contents of main elements in a high-lead, high-copper, high-iron and zinc concentrate are shown in the following table, wherein the contents of lead are 3.5%, copper are 2.1% and iron is 14.2%. Mixing the zinc concentrate with zinc sulfate and water according to a mass ratio of 95:4:1, granulating by using a cylindrical granulator after uniformly mixing, and ensuring that the prepared granules meet 0.5-5 mm, wherein 2-3 mm granules account for more than 75%. And drying the granulated material to ensure that the water content in the material is less than 1%.

At 10m²For example, the fluidized bed furnace can reach 26t/m²D, the feeding amount per hour is 10.83t, the roasting treatment is carried out at the temperature of 1100 ℃, the roasting time is 3h, the air blowing linear velocity is 2.5m/s, and the smoke dust output in the roasting process is 11.9 percent. The calcine produced by the fluidized bed furnace flows into a reduction furnace, selective reduction is carried out at 500 ℃ under the condition of hydrogen, the reduction time is 60min, and the soluble zinc in the reduction slag accounts for 99 percent of the total zinc mass. And (3) carrying out wet leaching (normal temperature and normal pressure leaching) on the reducing slag, wherein the mass ratio of zinc to iron in the leaching solution is 89:11, and electrolyzing and extracting the metal zinc after purifying the leaching solution.

TABLE 5 content of main constituents of a high-lead, high-copper, high-iron and high-zinc concentrate

Element(s)	Zn	Pb	Cu	Fe	S
						Content (wt.)	46.8	3.5	2.1	14.2	32.5

Example 5

The contents of main elements in a high-lead, high-copper, high-iron and zinc concentrate are shown in the following table, wherein the contents of lead are 3.5%, copper are 2.1% and iron is 14.2%. Mixing the zinc concentrate with zinc sulfate and water according to the mass ratio of 85:12:3, granulating by using a cylindrical granulator after uniformly mixing, and ensuring that the prepared granules meet the requirement of 0.5-5 mm, wherein the ratio of 2-3 mm granules is more than 75%. And drying the granulated material to ensure that the water content in the material is less than 1%.

At 10m²For example, the fluidized bed furnace can reach 26t/m²D, the feeding amount per hour is 10.83t, the roasting treatment is carried out at the temperature of 900 ℃, the roasting time is 5h, the air blowing linear velocity is 2.5m/s, and the smoke dust output in the roasting process is 9.8 percent. The calcine produced by the fluidized bed furnace flows into a reduction furnace, selective reduction is carried out at the temperature of 600 ℃ and under the condition of hydrogen, the reduction time is 120min, and the soluble zinc in the reduction slag accounts for 93 percent of the total zinc mass. And (3) carrying out wet leaching (normal temperature and normal pressure leaching) on the reducing slag, wherein the mass ratio of zinc to iron in the leaching solution is 95:5, and electrolyzing and extracting the metal zinc after purifying the leaching solution.

TABLE 6 content of major constituents of a high-lead, high-copper, high-iron and high-zinc concentrate

Element(s)	Zn	Pb	Cu	Fe	S
						Content (wt.)	46.8	3.5	2.1	14.2	32.5

Example 6

The contents of main elements in a high-lead, high-copper, high-iron and zinc concentrate are shown in the following table, wherein the contents of lead are 3.5%, copper are 2.1% and iron is 14.2%. Mixing the zinc concentrate with zinc sulfate and water according to a mass ratio of 92:6:2, granulating by using a cylindrical granulator after uniformly mixing, and ensuring that the prepared granules meet 0.5-5 mm, wherein 2-3 mm granules account for more than 75%. And drying the granulated material to ensure that the water content in the material is less than 1%.

At 10m²For example, the fluidized bed furnace can reach 26t/m²D, the feeding amount per hour is 10.83t, the roasting treatment is carried out at the temperature of 1000 ℃, the roasting time is 4h, the air blowing linear velocity is 2.5m/s, and the smoke dust output in the roasting process is 10.7 percent. The calcine produced by the fluidized bed furnace flows into a reduction furnace, selective reduction is carried out at 700 ℃ under the condition of hydrogen, the reduction time is 120min, and the soluble zinc in the reduction slag accounts for 99.5 percent of the total zinc mass. And (3) carrying out wet leaching (normal temperature and normal pressure leaching) on the reducing slag, wherein the mass ratio of zinc to iron in the leaching solution is 80:20, and electrolyzing and extracting the metal zinc after purifying the leaching solution.

TABLE 7 contents of main constituents of a high-lead, high-copper, high-iron and high-zinc concentrate

Element(s)	Zn	Pb	Cu	Fe	S
						Content (wt.)	46.8	3.5	2.1	14.2	32.5

Example 7

The contents of main elements in a high-lead, high-copper, high-iron and zinc concentrate are shown in the following table, wherein the contents of lead are 3.5%, copper are 2.1% and iron is 14.2%. Mixing the zinc concentrate with zinc sulfate and water according to a mass ratio of 92:6:2, granulating by using a cylindrical granulator after uniformly mixing, and ensuring that the prepared granules meet 0.5-5 mm, wherein 2-3 mm granules account for more than 75%. And drying the granulated material to ensure that the water content in the material is less than 1%.

At 10m²For example, the fluidized bed furnace can reach 26t/m²D, the feeding amount per hour is 10.83t, the roasting treatment is carried out at the temperature of 1000 ℃, the roasting time is 4h, the air blowing linear velocity is 2.5m/s, and the smoke dust output in the roasting process is 10.7 percent. The calcine produced by the fluidized bed furnace flows into the reduction furnaceAnd (3) carrying out selective reduction in the furnace at 450 ℃ under the condition of hydrogen for 240min, wherein soluble zinc in the reduction slag accounts for 92% of the total mass of zinc. And (3) carrying out wet leaching (normal temperature and normal pressure leaching) on the reducing slag, wherein the mass ratio of zinc to iron in the leaching solution is 90:10, and electrolyzing and extracting the metal zinc after purifying the leaching solution.

TABLE 8 content of main components of a high-lead, high-copper, high-iron and high-zinc concentrate

Element(s)	Zn	Pb	Cu	Fe	S
						Content (wt.)	46.8	3.5	2.1	14.2	32.5

Description of hydrogen reduction temperature and reduction time to soluble zinc ratio and zinc-iron mass ratio in leachate:

when the reduction temperature is low and the reduction time is short, the proportion of soluble zinc in the reduction slag is low, part of zinc exists in the form of zinc ferrite, and the part of zinc ferrite is difficult to leach, so that the proportion of zinc and iron in the leachate is high, but the total recovery rate of zinc is low; when in useWhen the reduction temperature is high and the reduction time is long, the proportion of soluble zinc in the reduction slag is high, but part of Fe₃O₄And the FeO can react with acid in the subsequent leaching process, so that the quality of zinc and iron in the leaching solution is low, and the purification cost of the wet leaching solution is increased. Therefore, proper reduction temperature and reduction time are required to be selected to ensure that the proportion of soluble zinc is higher, the zinc and iron content in the leachate is higher, the purification cost of the leachate is reduced, and the total recovery rate of zinc is improved.

Comparative example 1:

the contents of main elements in a high-lead, high-copper, high-iron and zinc concentrate are shown in the following table, wherein the contents of lead are 3.5%, copper are 2.1% and iron is 14.2%. Mixing the zinc concentrate with return dust (smoke dust returned in the oxidizing roasting treatment process) and dilute sulfuric acid (40 wt%) according to a mass ratio of 90:8:2, uniformly mixing, and granulating by using a disc granulator to ensure that the prepared granules meet the requirement of 0.5-5 mm, wherein the proportion of 1-2 mm granules is more than 75%. And drying the granulated material to ensure that the water content in the material is less than 1%.

At 10m²For example, the fluidized bed furnace can reach 24t/m²D, the feeding amount per hour is 10t, the roasting treatment is carried out at 1050 ℃, the roasting time is 4h, the linear velocity is 2.3m/s, and the smoke dust output in the roasting process is 11.5%. The soluble zinc in the calcine accounts for 84% of the total zinc mass, and the calcine is directly subjected to conventional wet leaching and electrolytic zinc extraction, so that the zinc recovery rate is about 83%.

TABLE 5 content of main constituents of a high-lead, high-copper, high-iron and high-zinc concentrate

Element(s)	Zn	Pb	Cu	Fe	S
						Content (wt.)	46.8	3.5	2.1	14.2	32.5

Comparative example 2:

the contents of main elements in a high-lead, high-copper, high-iron and zinc concentrate are shown in the following table, wherein the contents of lead are 3.5%, copper are 2.1% and iron is 14.2%. Mixing the zinc concentrate with return dust and dilute sulfuric acid according to a mass ratio of 90:8:2, granulating by using a disc granulator after uniformly mixing, and ensuring that the prepared particles meet 0.5-5 mm, wherein the proportion of 1-2 mm particles is more than 75%. And drying the granulated material to ensure that the water content in the material is less than 1%.

At 10m²For example, the fluidized bed furnace can reach 24t/m²D, the feeding amount per hour is 10t, the roasting treatment is carried out at 1050 ℃, the roasting time is 4h, the blowing linear velocity of air is 2.3m/s, and the smoke dust output in the roasting process is 11.5%. The soluble zinc in the calcine accounts for 85% of the total zinc mass, the calcine is directly leached under the conditions of high temperature and high pressure (70-150 ℃, 0.5-1.5 Mpa), the mass ratio of zinc to iron in the leaching solution is 80:20, the total recovery rate of zinc is about 86%, but the iron removal process flow is long and the cost is high.

TABLE 6 content of major constituents of a high-lead, high-copper, high-iron and high-zinc concentrate

Element(s)	Zn	Pb	Cu	Fe	S
						Content (wt.)	46.8	3.5	2.1	14.2	32.5

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.