阅读说明：本技术 一种从钢铁企业含锌除尘灰中高效去除锌的处理装置及方法 (Treatment device and method for efficiently removing zinc from zinc-containing dedusting ash of iron and steel enterprises ) 是由 王会刚 吴龙 彭犇 岳昌盛 胡天麒 吴跃东 邱桂博 白智韬 张亮亮 卢忠飞 于 2019-10-21 设计创作，主要内容包括：本发明涉及一种从钢铁企业含锌除尘灰中高效去除锌的处理装置及方法。所述处理装置将除尘灰、粘结剂、还原剂按一定比例在混匀设备中充分混合均匀后,经挤压成型设备压成一定尺寸的团块,团块烘干后,于还原挥发设备上在一定温度下还原一定时间,得到的金属化富铁料冷却后储存备用；含锌蒸汽在收尘系统中降温、收集,得到的富锌灰储存备用。本发明工艺过程简单,投资和运营成本合理；处理后的含锌除尘灰,锌去除率大于92％,富锌灰中氧化锌的质量百分含量高于40％,金属化富铁球团中锌的质量百分含量低于0.3％,铁的金属化率高于75％,满足在钢厂利用的要求；实现了钢铁企业含锌除尘灰的全部利用,解决了含锌除尘灰难以利用的难题。(The invention relates to a treatment device and a method for efficiently removing zinc from zinc-containing dedusting ash of iron and steel enterprises. The treatment device is used for fully and uniformly mixing the dedusting ash, the binder and the reducing agent in a mixing device according to a certain proportion, then pressing the mixture into blocks with a certain size through an extrusion forming device, drying the blocks, reducing the blocks on a reduction volatilizing device for a certain time at a certain temperature, and cooling the obtained metallized iron-rich material and storing the cooled metallized iron-rich material for later use; and (4) cooling and collecting the zinc-containing steam in a dust collection system, and storing the obtained zinc-rich ash for later use. The invention has simple process and reasonable investment and operation cost; the zinc removal rate of the treated zinc-containing fly ash is more than 92 percent, the mass percentage of zinc oxide in the zinc-rich ash is higher than 40 percent, the mass percentage of zinc in the metallized iron-rich pellets is lower than 0.3 percent, and the metallization rate of iron is higher than 75 percent, so that the zinc-containing fly ash meets the requirements of utilization in steel mills; the method realizes the complete utilization of the zinc-containing fly ash in iron and steel enterprises and solves the difficult problem that the zinc-containing fly ash is difficult to utilize.)

1. A treatment device for efficiently removing zinc from zinc-containing fly ash of iron and steel enterprises, which is characterized by comprising: the device comprises a storage bin (1), a conveying device (3), a blending device (4), an extrusion forming device (5), a drying device (6), a belt type reduction volatilizing device (7), a heating device (8), an induced draft system (9), a zinc-rich dust and high-temperature air separation system (10), a high-temperature air conveying pipeline (11) and an iron-rich material cooling system (13); the storage bin (1) is arranged above the transportation equipment (3) and used for weighing and conveying zinc-containing dedusting ash, a binder and a reducing agent stored in the storage bin (1) to the transportation equipment (3), the transportation equipment (3) is connected with the blending equipment (4) and used for conveying the zinc-containing dedusting ash, the binder and the reducing agent to the blending equipment (4) for uniform mixing so as to form a uniformly mixed material, and the blending equipment (4) is connected with the extrusion forming equipment (5) and used for extruding the material through the extrusion forming equipment (5); the extrusion forming equipment (5) is connected with the drying equipment (6) and is used for drying the raw extrusion block mass pressed by the extrusion forming equipment (5) through the drying equipment (6); the drying device (6) is connected with the reduction volatilization device (7) and is used for conveying the dried raw extruded lumps to the charging end of the reduction volatilization device (7) for material distribution; the heating device (8) is arranged at the upper part of the reduction volatilization device (7) and is used for heating the raw extruded lumps after the material distribution is finished so as to reduce and volatilize zinc and obtain iron-rich materials; the discharge end of the reduction volatilization equipment (7) is connected with an iron-rich material cooling system (13) and is used for cooling the iron-rich material; the inlet end of the induced draft system (9) is connected with the reduction volatilization equipment (7), and the outlet end of the induced draft system (9) is connected with the zinc-rich dust and high-temperature air separation system (10) and is used for conveying zinc-containing dust formed in the reduction volatilization process to the dust and high-temperature air separation system (10) for collecting the zinc-rich dust; the zinc-rich dust and high-temperature air separation system (10) is connected with the drying equipment (6) through a high-temperature air conveying pipeline (11) and is used for conveying the high-temperature air separated from the zinc-rich dust to the drying equipment (6) to dry the pressed raw extruded briquettes.

2. the processing plant according to claim 1, characterized in that it further comprises a weighing device (2) arranged between the storage bin (1) and the transport device (3) for weighing the zinc containing fly ash, the binder and the reducing agent.

3. the processing plant according to claim 1 or 2, further comprising a zinc-rich dust storage site (12) and an iron-rich material storage site (14), wherein the zinc-rich dust storage site (12) is connected with the zinc-rich dust and high temperature air separation system (10) and is used for conveying the collected zinc-rich dust to the zinc-rich dust storage site (12) for storage; the iron-rich material storage site (14) is connected with the iron-rich material cooling system (13) and is used for conveying the cooled iron-rich material to the iron-rich material storage site (14) for storage and standby.

4. A treatment plant according to any of claims 1-3, characterized in that said reduction and volatilization equipment (7) is in the form of a conveyor belt having a feed end and a discharge end for advancing the green pressed agglomerates from the feed end to the discharge end of said reduction and volatilization equipment (7) for performing the reduction and volatilization of zinc in the zinc-containing fly ash and the metallization of the iron-containing material.

5. Treatment device according to one of claims 1 to 4, characterized in that the air induction system (9) is downwardly induced.

6. the processing apparatus according to any one of claims 1 to 5, wherein the green extrudate is in the form of spheres or blocks and the iron-rich material is in the form of spheres or blocks.

7. A treatment method for efficiently removing zinc from zinc-containing fly ash of iron and steel enterprises is characterized by comprising the following steps:

(1) Zinc-containing fly ash, a reducing agent and a binder which are stored in a storage bin (1) are weighed on a weighing device (2), wherein the zinc-containing fly ash, the reducing agent and the binder are in a mass ratio of: 82-90: 8-15: 2-3, and then conveying the mixture to a mixing device (4) through a conveying device (3) for mixing uniformly;

(2) Spraying water during the mixing process, preferably ensuring that the mass percentage of water in the mixture is kept between 8 and 12 percent;

(3) Pressing the uniformly mixed materials in a ball pressing device (5) to generate an extrusion briquette, preferably a briquette with the diameter of 10-25 mm;

(4) drying the pressed green extrusion blocks in a drying device (6), preferably reducing the mass content of water in the pellets to about 2%;

(5) Distributing the dried extrusion blocks on reduction volatilization equipment (7), preferably controlling the thickness of a material layer to be less than 300mm, igniting the heating equipment (8) after the distribution is finished to heat the extrusion blocks to 1200-1250 ℃, and finishing the reduction volatilization of zinc and the metallization of iron-containing materials after 20-40 min;

(6) The reduced metal zinc steam is cooled and oxidized in a downward air induction system (9) and is conveyed to a zinc-rich dust and high-temperature air separation system (10) to finish the collection of the zinc-rich dust; meanwhile, the zinc-rich dust and the high-temperature air separated by the high-temperature air separation system (10) are conveyed to a drying device (6) and used for drying the raw extruded lumps in the drying device (6);

(7) The iron-rich material is discharged to a cooling system (13) at the discharge end of the reduction volatilization equipment (7), is preferably cooled to below 300 ℃, and is stored for later use in an iron-rich material storage site (14).

8. The process according to claim 7, wherein the reducing agent is coke or pulverized coal or the like, and the binder is bentonite or the like; the raw extruded lumps are spherical or blocky, and the iron-rich material is spherical or blocky; determining the dosage of a reducing agent according to the chemical composition of the zinc-containing dedusting ash to ensure the reduction of zinc and iron oxide; the amount of binder is determined according to the strength of the green extruded mass, preferably to ensure that the mass has a strength of more than 10 drops at 0.5 m.

9. The process of claim 7 wherein the water spray operation ensures that the water is sprayed in a mist form; and under the condition that the zinc-rich dust and the high-temperature air of the high-temperature air separation system (10) can not finish drying the raw extruded briquette, an external heating source is adopted for drying.

10. the process according to any one of claims 7 to 9, characterized in that the zinc content in the iron-rich material is less than 0.3% by mass.

Technical Field

The invention relates to a device and a method for efficiently removing zinc from zinc-containing dedusting ash of iron and steel enterprises, belongs to the field of waste recycling, and particularly relates to a belt type reduction and volatilization device and a downward air induction system, and a device and a method for obtaining zinc-rich dust and metallized iron-containing pellets.

background

the metallurgical dust removal ash is a solid waste containing iron with a large output, and the production amount of each ton of steel is 100-150 kg. In recent years, due to the pressure of iron ore resource shortage and pollutant discharge control, most steel enterprises adopt a return sintering method to utilize the dedusting ash. However, metallurgical dust removal ash has complex composition, particularly, some dust removal ash has high zinc content, and the quality of coke in a blast furnace can be influenced after the dust removal ash is sintered and enters the blast furnace, so that the smooth operation of the blast furnace is influenced. Therefore, zinc-containing fly ash which is difficult to utilize has to be accumulated and stored, which not only causes serious pollution to the environment, but also causes waste of valuable resources (ludong rui. saddle steel technology, 2019(03):7-10+ 18). According to the requirements of the design Specification of blast furnace ironmaking process (GB50427-2008) in China, the zinc load of a blast furnace is lower than 0.15 kg/t. Therefore, the efficient removal of zinc from the zinc-containing fly ash has become a research hotspot for metallurgists.

For removing zinc in the dust, metallurgists successively develop a wet-process zinc removal process and a fire-process zinc removal process. In general, the wet process has low energy consumption and low equipment investment, but the production efficiency and the zinc removal rate are low, and the method is sensitive to raw materials and difficult to optimize, so that the method cannot be used in a large scale. The fire method dezincing process mainly comprises the technologies of a rotary hearth furnace, a rotary kiln, OxyCup and the like. The carbon-containing pellets are mainly heated by heat radiation in the rotary hearth furnace process, and the heat utilization rate is only about 50 percent. And the thermal regulation and atmosphere in the rotary hearth furnace are not easy to control. Although the rotary kiln process has low operation cost, the rotary kiln process has the advantages of mature process, low investment, simple operation and the like. However, the rotary kiln process is not suitable for treating low-zinc fly ash, the metallization rate of iron materials is low, and the ring formation phenomenon is often generated in the production process (Yin Lei Ming, Anhui university of Industrial science, 2017). Although the OxyCup process has low requirement on furnace charge and relatively flexible production, the process has the defects of low operation rate, short service life of furnace lining, high brick making cost and the like.

Therefore, the three pyrometallurgical processes can treat the zinc-containing fly ash of iron and steel enterprises, but have certain disadvantages.

Disclosure of Invention

In order to solve the defects in the background technology, the invention adopts a reduction and volatilization device to reduce the zinc-containing dedusting ash to obtain zinc-rich ash and metallized iron-containing pellets, heats the pellets from the upper part, and collects the zinc-rich ash by a downward air induction system. The method can realize the resource full utilization of the zinc-containing fly ash of iron and steel enterprises and solve the problem that the zinc-containing fly ash is difficult to utilize. Compared with a rotary hearth furnace, the rotary hearth furnace has the advantages of simple process, low investment and operation cost, low accident rate, high heat efficiency and the like.

The invention provides a treatment device for efficiently removing zinc from zinc-containing dedusting ash of iron and steel enterprises, which comprises: the device comprises a storage bin (1), a conveying device (3), a blending device (4), an extrusion forming device (5), a drying device (6), a belt type reduction volatilizing device (7), a heating device (8), an induced draft system (9), a zinc-rich dust and high-temperature air separation system (10), a high-temperature air conveying pipeline (11) and an iron-rich material cooling system (13); the storage bin (1) is arranged above the transportation equipment (3) and used for weighing and conveying zinc-containing dedusting ash, a binder and a reducing agent stored in the storage bin (1) to the transportation equipment (3), the transportation equipment (3) is connected with the blending equipment (4) and used for conveying the zinc-containing dedusting ash, the binder and the reducing agent to the blending equipment (4) for uniform mixing so as to form a uniformly mixed material, and the blending equipment (4) is connected with the extrusion forming equipment (5) and used for extruding the material through the extrusion forming equipment (5); the extrusion forming equipment (5) is connected with the drying equipment (6) and is used for drying the raw extrusion block mass pressed by the extrusion forming equipment (5) through the drying equipment (6); the drying device (6) is connected with the reduction volatilization device (7) and is used for conveying the dried raw extruded lumps to the charging end of the reduction volatilization device (7) for material distribution; the heating device (8) is arranged at the upper part of the reduction volatilization device (7) and is used for heating the raw extruded lumps after the material distribution is finished so as to reduce and volatilize zinc and obtain iron-rich materials; the discharge end of the reduction volatilization equipment (7) is connected with an iron-rich material cooling system (13) and is used for cooling the iron-rich material; the inlet end of the induced draft system (9) is connected with the reduction volatilization equipment (7), and the outlet end of the induced draft system (9) is connected with the zinc-rich dust and high-temperature air separation system (10) and is used for conveying zinc-containing dust formed in the reduction volatilization process to the dust and high-temperature air separation system (10) for collecting the zinc-rich dust; the zinc-rich dust and high-temperature air separation system (10) is connected with the drying equipment (6) through a high-temperature air conveying pipeline (11) and is used for conveying the high-temperature air separated from the zinc-rich dust to the drying equipment (6) to dry the pressed raw extruded briquettes.

The processing device also comprises a weighing device (2) which is arranged between the storage bin (1) and the transportation device (3) and is used for weighing the zinc-containing dedusting ash, the binder and the reducing agent.

the processing device further comprises a zinc-rich dust storage site (12) and an iron-rich material storage site (14), wherein the zinc-rich dust storage site (12) is connected with the zinc-rich dust and high-temperature air separation system (10) and is used for conveying the collected zinc-rich dust to the zinc-rich dust storage site (12) for storage; the iron-rich material storage site (14) is connected with the iron-rich material cooling system (13) and is used for conveying the cooled iron-rich material to the iron-rich material storage site (14) for storage and standby.

the reduction and volatilization equipment (7) is in a conveying belt form and is provided with a feeding end and a discharging end, and the raw extrusion block mass is conveyed from the feeding end to the discharging end of the reduction and volatilization equipment (7) to complete the reduction and volatilization of zinc and the metallization of iron-containing materials.

wherein the air inducing system (9) induces air downwards.

Wherein, the raw extruded lumps are spherical or blocky, and the iron-rich material is spherical or blocky.

The invention also relates to a treatment method for efficiently removing zinc from the zinc-containing fly ash of iron and steel enterprises, which comprises the following steps:

(1) Zinc-containing fly ash, a reducing agent and a binder which are stored in a storage bin (1) are weighed on a weighing device (2), wherein the zinc-containing fly ash, the reducing agent and the binder are in a mass ratio of: 82-90: 8-15: 2-3, and then conveying the mixture to a mixing device (4) through a conveying device (3) for mixing uniformly;

(2) spraying water during the mixing process, preferably ensuring that the mass percentage of water in the mixture is kept between 8 and 12 percent;

(3) pressing the uniformly mixed materials in a ball pressing device (5) to generate an extrusion briquette, preferably a pellet with the diameter of 10-25 mm;

(4) Drying the pressed green extrusion blocks in a drying device (6), preferably reducing the mass content of water in the pellets to about 2%;

(5) distributing the dried extrusion blocks on reduction volatilization equipment (7), preferably controlling the thickness of a material layer to be less than 300mm, igniting the heating equipment (8) after the distribution is finished to heat the extrusion blocks to 1200-1250 ℃, and finishing the reduction volatilization of zinc and the metallization of iron-containing materials after 20-40 min;

(6) The reduced metal zinc steam is cooled and oxidized in a downward air induction system (9) and is conveyed to a zinc-rich dust and high-temperature air separation system (10) to finish the collection of the zinc-rich dust; meanwhile, the zinc-rich dust and the high-temperature air separated by the high-temperature air separation system (10) are conveyed to a drying device (6) and used for drying the raw extruded lumps in the drying device (6);

(7) the iron-rich material is discharged to a cooling system (13) at the discharge end of the reduction volatilization equipment (7), is preferably cooled to below 300 ℃, and is stored for later use in an iron-rich material storage site (14).

wherein the reducing agent is coke or coal powder and the like, and the binder is bentonite and the like; the raw extruded lumps are spherical or blocky, and the iron-rich material is spherical or blocky; determining the dosage of a reducing agent according to the chemical composition of the zinc-containing dedusting ash to ensure the reduction of zinc and iron oxide; the amount of binder is determined according to the strength of the green extruded mass, preferably to ensure that the mass has a strength of more than 10 drops at 0.5 m.

Wherein, the water spraying operation ensures that water is sprayed in a mist shape; and under the condition that the zinc-rich dust and the high-temperature air of the high-temperature air separation system (10) can not finish drying the raw extruded briquette, an external heating source is adopted for drying.

wherein the mass percent of zinc in the gold iron-rich material is less than 0.3 percent

In addition, the technical scheme of the invention is preferably as follows:

the device for efficiently removing zinc from zinc-containing fly ash of iron and steel enterprises comprises: the device comprises a zinc-containing dedusting ash, a binder, a reducing agent storage bin, a weighing device, a transportation device, a blending device, an extrusion forming device, a drying device, a belt type reduction volatilization device, a heating device, an induced air system, a zinc-rich dust and high-temperature air separation system, a high-temperature air conveying pipeline, a zinc-rich dust storage site, a metalized iron-containing iron pellet cooling system and an iron-containing pellet storage site.

the zinc-containing dedusting ash, the binder and the reducing agent stored in the storage bin are weighed by a weighing device and then conveyed to a material mixing device by a conveying device, and the mixed material is extruded and formed by an extrusion forming device; drying the extruded raw extruded briquette by a drying device, then distributing the material at the charging end of a belt type reduction and volatilization device, heating the raw extruded briquette to a certain temperature by a heating device after the material distribution is finished, and after reacting for a certain time, moving the extruded briquette to the discharging end of the belt type reduction and volatilization device for discharging; in the reduction and volatilization process of the extruded briquette, zinc-containing dust is brought into a dust and high-temperature air separation system by an induced air system, meanwhile, the high-temperature zinc-rich dust is cooled and deposited, and the collected zinc-rich dust is stored in a zinc-rich dust storage place; leading the high-temperature air separated from the zinc-rich dust to raw extrusion briquette drying equipment through a high-temperature air conveying pipeline for drying raw extrusion briquettes; and cooling the iron-rich material left after the zinc evaporation by a cooling system, and storing the iron-rich material in a storage place for later use.

Wherein, the raw extruded lumps dried by the drying equipment move from the feeding end to the discharging end of the belt type reduction volatilization equipment to finish the reduction volatilization of zinc and the metallization of iron-containing materials.

Wherein, the belt type reduction volatilization equipment heats the extruded briquette by the heating equipment above.

and the air inducing system of the reduction volatilization device induces air downwards, and the collection of zinc-rich ash and the separation of high-temperature air are completed in the zinc-rich dust and high-temperature air separation system.

Wherein, the high-temperature air separated by the zinc-rich dust and high-temperature air separation system is used for drying the pressed raw extruded briquette by drying equipment.

In addition, preferably, the invention also relates to a method for efficiently removing zinc from zinc-containing fly ash of iron and steel enterprises, which comprises the following steps:

(1) the zinc-containing dedusting ash, the reducing agent and the binder stored in the storage bin are weighed on weighing equipment according to the mass ratio of 82-90: 8-15: 2-3, and then are transported to mixing equipment through transporting equipment;

(2) spraying water during the mixing process to ensure that the mass percentage of water in the mixture is kept between 8 and 12 percent;

(3) pressing the uniformly mixed materials into extruded blocks with the diameter of about 10-25 mm in extrusion forming equipment;

(4) Drying the pressed green extruded blocks in a drying device to reduce the mass percentage of water in the pellets to about 2%;

(5) distributing the dried blocks on reduction volatilization equipment, controlling the thickness of a material layer to be below 300mm, igniting by heating equipment after distributing the materials to heat the blocks to 1200-1250 ℃, and completing the reduction volatilization and metallization processes after 20-40 min;

(6) and the reduced metal zinc steam is cooled and oxidized in a downward induced air system, and the collection of zinc-rich dust is completed in a zinc-rich dust and high-temperature air separation system, wherein the mass percentage of zinc oxide in the zinc-rich dust is more than 40%. Meanwhile, high-temperature air is used for drying the green extrusion briquette by drying equipment;

(7) And discharging the iron-rich material to a cooling system at the discharge end of the reduction volatilization device, cooling to below 300 ℃, and storing in a storage site for later use.

wherein the reducing agent is coke or coal powder and the like, and the binder is bentonite and the like; determining the dosage of a reducing agent according to the chemical composition of the zinc-containing dedusting ash to ensure the reduction of zinc and iron oxide; the dosage of the binder is determined according to the strength of the green extrusion blocks, and the 0.5m falling strength of the ball is ensured to be more than 10 times.

Wherein, the water spraying operation ensures that water is sprayed in a mist shape.

Wherein, the mixed materials can be extruded into a ball shape or a block shape;

If the zinc-rich dust and the high-temperature air of the high-temperature air separation system can not finish the drying of the green agglomerates, an external heat source can be used.

Wherein the mass percentage of zinc in the metallized iron-rich material is less than 0.3 percent.

The invention has the advantages of realizing the high-efficiency removal of zinc in the zinc-containing dust of the iron and steel enterprises on the device and the method, simple technical process, lower investment and operation cost than that of a rotary hearth furnace and low accident rate. The zinc-containing dedusting ash treated by the process has the zinc removal rate of more than 92 percent, the mass percentage of zinc oxide in the zinc-rich ash is higher than 40 percent, the mass percentage of zinc in the metallized iron-containing pellets is lower than 0.3 percent, and the metallization rate of iron is higher than 75 percent, so that the zinc-containing dedusting ash meets the requirements of utilization in steel mills. The method realizes the complete utilization of the zinc-containing fly ash in iron and steel enterprises, and solves the problem that the zinc-containing fly ash is difficult to utilize.

Drawings

FIG. 1 is a schematic structural diagram of a treatment device for efficiently removing zinc from zinc-containing fly ash in iron and steel enterprises.

Detailed Description

a treatment apparatus for efficiently removing zinc from zinc-containing fly ash of iron and steel enterprises, as shown in fig. 1, comprises: the device comprises a storage bin 1, a transportation device 3, a blending device 4, an extrusion forming device 5, a drying device 6, a belt type reduction volatilization device 7, a heating device 8, an induced draft system 9, a zinc-rich dust and high-temperature air separation system 10, a high-temperature air conveying pipeline 11 and an iron-rich material cooling system 13; the storage bin 1 is arranged above the transportation equipment 3 and used for weighing the zinc-containing dedusting ash, the binder and the reducing agent stored in the storage bin 1 and then conveying the zinc-containing dedusting ash, the binder and the reducing agent to the transportation equipment 3, the transportation equipment 3 is connected with the blending equipment 4 and used for conveying the zinc-containing dedusting ash, the binder and the reducing agent to the blending equipment 4 to be uniformly mixed so as to form uniformly mixed materials, and the blending equipment 4 is connected with the extrusion forming equipment 5 and used for extruding the materials through the extrusion forming equipment 5; the extrusion forming equipment 5 is connected with the drying equipment 6 and is used for drying the raw extrusion block mass pressed by the extrusion forming equipment 5 through the drying equipment 6; the drying device 6 is connected with the reduction volatilization device 7 and is used for conveying the dried raw extruded lumps to the charging end of the reduction volatilization device 7 for material distribution; the heating device 8 is arranged at the upper part of the reduction volatilization device 7 and is used for heating the raw extruded lumps after the material distribution is finished so as to reduce and volatilize zinc and obtain iron-rich materials; the discharge end of the reduction volatilization equipment 7 is connected with an iron-rich material cooling system 13 and is used for cooling the iron-rich material; the inlet end of the induced draft system 9 is connected with the reduction volatilization equipment 7, and the outlet end of the induced draft system 9 is connected with the zinc-rich dust and high-temperature air separation system 10, and is used for conveying zinc-containing dust formed in the reduction volatilization process to the dust and high-temperature air separation system 10 for collecting the zinc-rich dust; the zinc-rich dust and high-temperature air separation system 10 is connected with the drying equipment 6 through a high-temperature air conveying pipeline 11, and is used for conveying high-temperature air separated from the zinc-rich dust to the drying equipment 6 to dry pressed raw extruded briquettes.

Wherein, the processing device also comprises a weighing device 2 which is arranged between the storage bin 1 and the transportation device 3 and is used for weighing the zinc-containing dust, the binder and the reducing agent. The processing device further comprises a zinc-rich dust storage site 12 and an iron-rich material storage site 14, wherein the zinc-rich dust storage site 12 is connected with the zinc-rich dust and high-temperature air separation system 10 and is used for conveying the collected zinc-rich dust to the zinc-rich dust storage site 12 for storage; the rich iron material storage site 14 is connected with the rich iron material cooling system 13 and is used for conveying the cooled rich iron material to the rich iron material storage site 14 for storage and standby. The reduction volatilization equipment 7 is in a conveying belt form or in a chain form, is provided with a feeding end and a discharging end, and is used for moving the raw extrusion block mass from the feeding end to the discharging end of the reduction volatilization equipment 7 so as to complete the reduction volatilization of zinc and the metallization of iron-containing materials. Wherein the induced air system 9 is used for inducing air downwards. Wherein, the raw extruded lumps are spherical or blocky, and the iron-rich material is spherical or blocky.

Preferably, the spherical shape is taken as an example, and as shown in fig. 1, a preferred processing apparatus includes: zinc-containing dedusting ash, a binder and a reducing agent storage bin 1, a weighing device 2, a conveying device 3, a blending device 4, an extrusion forming device 5, a drying device 6 and a belt type reduction volatilizing device 7, wherein a chain type device can be adopted, a heating device 8, an induced air system 9, a zinc-rich dust and high-temperature air separation system 10, a high-temperature air conveying pipeline 11, a zinc-rich dust storage site 12, an iron-rich material cooling system 13 and an iron-rich material storage site 14. Zinc-containing dedusting ash, bentonite and coal dust stored in a storage bin 1 are weighed by a weighing device 2, conveyed to a material mixing device 4 by a conveying device 3, and subjected to ball pressing operation by an extrusion forming device 5, wherein the water content of the mixed material is 10%; drying the extruded green pellets by a drying device 6 until the mass percentage of moisture in the green pellets is about 2%, then distributing the raw pellets to a thickness of less than 300mm at the charging end of a belt-type reduction and volatilization device 7, heating the green pellets to 1200-1250 ℃ by a heating device 8 after distributing, reacting for 20-30 min, and then conveying the green pellets to the discharging end of the belt-type reduction and volatilization device for discharging; in the process of pellet reduction and volatilization, zinc-containing dust is brought into a dust and high-temperature air separation system 10 by an induced air system 9, meanwhile, the high-temperature zinc-rich dust is cooled and deposited, and the collected zinc-rich dust is stored in a zinc-rich dust storage site 12; the high-temperature air separated from the zinc-rich dust is led to green pellet drying equipment 6 through a high-temperature air conveying pipeline 11 and is used for drying pressed green pellets; the metallized iron-rich pellets remaining after the zinc evaporation are cooled by a cooling system 13 and stored in a storage site 14 for later use.

the invention also relates to a method for efficiently removing zinc from the zinc-containing dedusting ash of the iron and steel enterprises, which comprises the following steps:

(1) The chemical composition of the zinc-containing fly ash for the test is shown in table 1, and the zinc-containing fly ash, coal powder and bentonite stored in the storage bin are as follows, wherein the zinc-containing fly ash, the reducing agent and the binder are in mass ratio: 82-90: 8-15: 2-3, preferably weighing on a weighing device according to a mass ratio of 89:8.5:2.5, and then transporting to a blending device through a transporting device;

Table 1 chemical composition (wt.%) of dust containing zinc for testing

(2) Performing mist water spraying operation simultaneously in the mixing process to keep the mass percentage of water in the mixture at 10%;

(3) pressing the uniformly mixed materials into pellets with the diameter of about 15mm in extrusion forming equipment;

(4) Drying the extruded green pellets in a drying device to reduce the mass percentage of water in the green pellets to about 2%;

(5) Distributing the dried pellets on reduction volatilization equipment, controlling the thickness of a material layer to be below 300mm, igniting by heating equipment after distributing the material to heat the pellets to 1200-1250 ℃, and completing the reduction volatilization and metallization processes after 20-30 min;

(6) The reduced metal zinc steam is cooled and oxidized again in a downward induced air system, the collection of zinc-rich dust is completed in a zinc-rich dust and high-temperature air separation system, and meanwhile, high-temperature air is used for drying green balls by drying equipment;

(7) and discharging the metallized iron-rich pellets to a cooling system at the discharge end of the reduction volatilization device, cooling to below 300 ℃, and storing in a storage site for later use.

The test results are illustrated below:

The zinc-containing dedusting ash treated by the process has the zinc removal rate of 94.12 percent, the zinc oxide content in the zinc-rich ash of 42.16 percent by mass, the zinc content in the metallized iron-rich pellet of 0.28 percent by mass and the iron metallization rate of 80.15 percent, and meets the requirements of steel mills.

the above embodiments are provided only for illustrating the present invention and not for limiting the present invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and therefore all equivalent technical solutions should also fall within the scope of the present invention.