Method for recovering and utilizing electric furnace dust after dezincification

Abstract

The application provides a method for recycling electric furnace dust after dezincification. The method comprises the following steps: adding a composite binder and water into the electric furnace dust after dezincification in a fluidized bed furnace to prepare green balls, and then digesting, drying and solidifying the green balls to obtain cold solid pellets for electric furnace, which are added into molten steel in an electric furnace as a slagging agent together with slag materials, so that the iron resources in the electric furnace dust can be recycled, and the usage amount of limestone in the electric furnace steelmaking can be reduced. Meanwhile, the cold solid pellets for electric furnace can reduce the melting point and viscosity of molten slag due to the high alkalinity, so that the slagging time is shortened, the energy consumption of electric furnace smelting is reduced, the dephosphorization amount and dephosphorization rate in the electric furnace smelting are improved, and the quality of molten steel is improved. In addition, the cold solid pellets for electric furnace prepared do not need to be calcined at high temperature, so that the strength requirement of the pellets for electric furnace steelmaking is met, and the production cycle is shortened. The electric furnace dust after dezincification in the fluidized bed furnace contains more active CaO, and the balling performance is better than that of the electric furnace dust, so that the usage amount of the binder can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of comprehensive utilization of metallurgical furnace dust resources, and particularly relates to a method for recycling electric furnace dust after zinc removal. BACKGROUND

[0002] In recent years, with the rapid development of China's steel industry, electric furnace steelmaking, as one of the important ways of steel production, is increasingly valued by domestic steel enterprises. The total output of domestic electric furnace steelmaking accounts for only 10% of the total crude steel output. With the increase of scrap steel resources and the further deepening of industrial structure adjustment, China's electric furnace steelmaking will usher in a period of rapid development. In the process of electric furnace smelting, the production of electric furnace dust is 10-20 kg / ton of steel. The main components of electric furnace dust include Zn, Fe, Ca, Mg, Mn, Pb and other metal oxides. The main treatment method for electric furnace dust in China is fire treatment. Zinc and lead components in the furnace dust are reduced by using a reducing agent. The reduced zinc and lead are collected or re-oxidized into oxides after being separated from the furnace dust at high temperature. However, the existing treatment method has problems such as high energy consumption, complex process, low metal recovery rate, etc. At the same time, after the removal of zinc and lead from the electric furnace dust, the main components are iron oxides and other alkaline metal oxides, which have great potential value for utilization. However, some existing processes do not utilize the electric furnace dust after zinc removal in a high-quality manner, resulting in serious waste of resources.

[0003] Some patents introduce new methods for recovering zinc elements in metallurgical dust. For example, a method for collecting zinc powder in metallurgical ash provided in a patent with publication number CN110396601A uses a fluidized bed to blow nitrogen, then adds metallurgical dust preheated to 520-580 DEG C to the fluidized bed, and then increases the temperature to 980-1150 DEG C to reduce and collect zinc oxide into zinc vapor. The condensed waste gas is recycled in the fluidized bed to improve the removal rate of zinc. However, the remaining dust is not properly treated. A patent with publication number CN101092664A provides a method for treating zinc-containing electric furnace dust. The zinc-containing electric furnace dust is mixed with carbon, balling, and drying to form carbon-containing pellets. The dried carbon-containing pellets are loaded into a rotary hearth furnace for reduction roasting. The zinc vapor in the rotary hearth furnace is introduced into an oxidation chamber and oxidized to ZnO vapor at 1100-1250 DEG C. After cooling, zinc oxide powder with a ZnO content of more than 90% is obtained. The remaining pellets are semi-metalized pellets with a TFe content of more than 50% and a metallization rate of about 60%, and the single pellet strength can reach 7 kN, which can be used as blast furnace raw material.

[0004] In recent years, metallurgists have developed numerous technologies and processes for treating toxic zinc-containing electric arc furnace dust, mainly including the following aspects: focusing only on the harmless treatment of electric arc furnace dust without considering its resource utilization; focusing on the efficient extraction of zinc from the dust without considering the environmental impact of toxic elements; and using low-dust as a cement additive for low-value building materials without considering the high-value, green, and comprehensive utilization of valuable metal elements such as zinc. Currently, there is almost no research on the high-value utilization of dezincified materials both domestically and internationally. Most of the dezincified dust is disposed of through stockpiling or landfilling, and some steel plants reuse the semi-metallized pellets after dezincification as blast furnace feedstock. However, the metal recovery rate obtained from this treatment is low, and excessive calcium, magnesium, and silicon content leads to excessive blast furnace slag. With the development of electric arc furnace steelmaking, more electric arc furnace dust will urgently need to be treated, and a large amount of dezincified dust will also be generated. To avoid resource waste and environmental pollution, it is urgent to develop a high-quality process route for the utilization of dezincified electric arc furnace dust.

[0005] Based on the advantages of fluidized bed furnace reduction, such as good reduction conditions, high zinc recovery rate, precise temperature control, uniform heat distribution in the furnace, energy saving and environmental protection, the fluidized bed furnace reduction zinc extraction process has great development prospects in the future; as a new process for treating electric furnace dust, the electric furnace dust after fluidized bed zinc extraction has great potential research value.

[0006] Therefore, it is of great significance to develop a method that is simple to operate and can efficiently recycle and utilize electric furnace dust after zinc removal. Summary of the Invention

[0007] To address the shortcomings of the existing technology, the present invention aims to provide a method for recycling electric furnace dust after zinc removal. This method involves adding a composite binder and water to the electric furnace dust after zinc removal in a fluidized bed furnace and then forming it into green pellets under a certain pressure. The pellets are then sequentially digested, dried, and cured to obtain cold-solidified pellets for electric furnaces, which are then added to the molten steel in the electric furnace along with the slag as a slag-reducing agent.

[0008] To achieve the above objectives, the present invention provides a method for recycling electric furnace dust after zinc removal, comprising the following steps:

[0009] S1. Mix the dezincified electric furnace dust collected according to the predetermined mass ratio with the binder to obtain a solid material.

[0010] S2. Add a predetermined amount of water to the solid material obtained in step S1, mix it evenly again, and obtain a wet-mixed solid material.

[0011] S3. Press the wet-mixed solid material into pellets to obtain green pellets;

[0012] S4. The green pellets are shaped and screened, and the complete green pellets are digested at room temperature for a predetermined time;

[0013] S5. After drying and solidifying the green pellets processed in step S4, cold-solidified pellets for electric furnaces are obtained. The cold-solidified pellets for electric furnaces are added to the molten steel in the electric furnace as a slag-reducing agent together with the slag material.

[0014] Further, the electric furnace dust after zinc removal mentioned in step S1 is the electric furnace dust after zinc removal in a fluidized bed furnace; the components and contents of the electric furnace dust after zinc removal in the fluidized bed furnace are as follows: FeO: 24-33%, CaO: 12-16%, MgO: 9-11%, SiO2: 5-7%, Fe: 18-24%, MnO: 2-5%, ZnO: 2-7%, KCl: 5-8%.

[0015] Further, the predetermined mass ratio in step S1 is the electric furnace dust after zinc removal: binder = 90-100: 7-10; the time for uniform mixing is 2-5 minutes.

[0016] Further, the predetermined amount of water in step S2 is 9-12% of the mass of the solid material; the time for re-mixing is 4-6 minutes.

[0017] Furthermore, in step S3, the pressure at which the wet-mixed solid material is rubbed is 40-60 MPa.

[0018] Furthermore, the predetermined time for resolution in step S4 is 22 to 26 hours.

[0019] Furthermore, the predetermined requirements for the collected electric furnace dust after zinc removal in step S1 are: particle size of 70-100 mesh and bulk density of 540-600 kg / m³. 3 Specific surface area ≥1000cm² 2 / g, TFe > 40%.

[0020] Further, the binder in step S1 is composed of: 25-38% bentonite, 22-35% magnesium lignosulfonate, 13-26% puffed corn starch, and 10-25% silica.

[0021] Furthermore, the strength parameters of the green balls after digestion in step S4 are: drop strength > 8.5 times / 0.5m, compressive strength ≥ 420N / ball.

[0022] Further, the drying temperature in step S5 is 150-200℃, and the drying time is 2-4 hours; the moisture content of the dried electric furnace cold-fixed pellets is <2%; the strength parameters of the dried electric furnace cold-fixed pellets are: drop strength >35 times / 0.5m, compressive strength ≥2500N / pellet.

[0023] The beneficial effects of this invention are:

[0024] 1. The method for recycling electric furnace dust after zinc removal provided by this invention involves adding a composite binder and water to the electric furnace dust after zinc removal in a fluidized bed furnace, and then forming it into green pellets under a certain pressure. These green pellets are then sequentially digested, dried, and solidified to obtain cold-solidified pellets for electric furnaces. These pellets are then added to the molten steel in the electric furnace along with the slag. This treatment not only recovers the abundant iron resources but also reduces the amount of limestone used in electric furnace steelmaking, lowering production costs. Simultaneously, these high-basicity cold-solidified pellets for electric furnaces can lower the melting point and viscosity of the slag, and can be used as an oxidant, slag remover, and temperature regulator in the electric furnace steelmaking process. This shortens the slag removal time, reduces energy consumption in electric furnace smelting, and helps improve the amount and rate of dephosphorization in electric furnace smelting, thus contributing to the improvement of molten steel quality. Furthermore, because the electric furnace dust particles after zinc removal from the fluidized bed furnace are relatively small, they are easy to process and have low recycling costs. Moreover, they do not require high-temperature roasting to meet the strength requirements for electric furnace steelmaking pellets, resulting in a short production cycle and low production costs. This virtuous cycle of electric furnace dust—from the electric furnace to the electric furnace dust removal system and back to the electric furnace—not only solves the pollution problem caused by the stockpiling of electric furnace dust after zinc removal but also realizes the recycling of metallurgical resources. It aligns with the development concept of green production and is an economical and environmentally friendly utilization method. It is also the only way to achieve high-value recycling of metallurgical resources from electric furnace dust in the future.

[0025] 2. The method for recycling electric furnace dust after zinc removal provided by the present invention contains more active CaO in the electric furnace dust after zinc removal in a fluidized bed furnace. The powder has better pelletizing performance than electric furnace dust. Under the same conditions, the amount of binder used is lower, which can reduce the amount of binder used and reduce production costs.

[0026] 3. The method for recycling electric furnace dust after zinc removal provided by this invention uses a composite binder that has minimal impact on the composition of molten steel, which is beneficial to the electric furnace steelmaking process. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the process flow provided in Embodiment 1 of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to specific embodiments.

[0029] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0030] The present invention provides a method for recycling electric furnace dust after zinc removal, comprising the following steps:

[0031] S1. Mix the dezincified electric furnace dust collected according to the predetermined mass ratio with the binder to obtain a solid material.

[0032] S2. Add a predetermined amount of water to the solid material obtained in step S1, mix it evenly again, and obtain a wet-mixed solid material.

[0033] S3. Press the wet-mixed solid material into pellets to obtain green pellets;

[0034] S4. The green pellets are shaped and screened, and the complete green pellets are digested at room temperature for a predetermined time;

[0035] S5. After drying and solidifying the green pellets processed in step S4, cold-solidified pellets for electric furnaces are obtained. The cold-solidified pellets for electric furnaces are added to the molten steel in the electric furnace as a slag-reducing agent together with the slag material.

[0036] This setup allows for the preparation of cold-solidified pellets for electric furnace steelmaking from dezincified electric furnace dust. These pellets do not require high-temperature calcination to meet the strength requirements of electric furnace steelmaking pellets, resulting in a short production cycle and low production costs. Furthermore, the dezincified electric furnace dust contains a significant amount of active CaO, leading to better pelletizing performance compared to other electric furnace dust. Under the same conditions, it requires less binder, thus reducing the amount of binder used and lowering production costs.

[0037] Preferably, in some embodiments of the present invention, the electric furnace dust after zinc removal in step S1 is electric furnace dust after zinc removal in a fluidized bed furnace; the components and contents of the electric furnace dust after zinc removal in the fluidized bed furnace are: FeO: 24-33%, CaO: 12-16%, MgO: 9-11%, SiO2: 5-7%, Fe: 18-24%, MnO: 2-5%, ZnO: 2-7%, KCl: 5-8%. The predetermined requirements for the electric furnace dust after zinc removal collected in step S1 are: particle size of 70-100 mesh and bulk density of 540-600 kg / m³. 3 Specific surface area ≥1000cm² 2 / g, TFe > 40%.

[0038] This configuration results in smaller particle sizes of electric arc furnace dust after zinc removal from the fluidized bed furnace, simplifying processing and reducing recycling costs. The dezincified electric arc furnace dust involved in this invention has a high total iron content (greater than 40%) and contains a significant amount of alkaline oxides. The low viscosity of the slag system after slagging in the electric arc furnace is beneficial for improving the quality of molten steel produced in the electric arc furnace. Furthermore, it effectively recovers iron resources while reducing limestone usage, thus lowering production costs.

[0039] Preferably, in some embodiments of the present invention, the predetermined mass ratio in step S1 is the electric furnace dust after zinc removal: binder = 90-100: 7-10; and the time for uniform mixing is 2-5 minutes.

[0040] With this setup, the dezincified dust contains more active CaO, and the dust pelletizing performance is better than that of electric furnace dust. Under the same conditions, the amount of binder used is lower, which can reduce the amount of binder used.

[0041] Preferably, in some embodiments of the present invention, the predetermined amount of water in step S2 is 9-12% of the mass of the solid material; the time for re-mixing is 4-6 minutes. The pressure at which the wet-mixed solid material is briquetized in step S3 is 40-60 MPa. The predetermined digestion time in step S4 is 22-26 hours.

[0042] Preferably, in some embodiments of the present invention, the binder in step S1 is composed of: 25-38% bentonite, 22-35% magnesium lignosulfonate, 13-26% puffed corn starch, and 10-25% silicon dioxide.

[0043] With this setup, the composite binder used in this process has a high content of organic components, which has minimal impact on the composition of the molten steel and is beneficial to the electric arc furnace steelmaking process.

[0044] Preferably, in some embodiments of the present invention, the green pellets after digestion in step S4 have the following strength parameters: drop strength > 8.5 times / 0.5m, compressive strength ≥ 420N / pellet. The drying temperature in step S5 is 150–200°C, and the drying time is 2–4 hours; the moisture content of the dried electric furnace chilled pellets is < 2%; the strength parameters of the dried electric furnace chilled pellets are: drop strength > 35 times / 0.5m, compressive strength ≥ 2500N / pellet.

[0045] With this configuration, the present invention prepares dezincified electric furnace dust into cold-solidified pellets for electric furnaces, which can meet the strength requirements of electric furnace steelmaking pellets without high-temperature calcination, resulting in a short production cycle and low production cost.

[0046] The following describes in detail the method for recycling and utilizing electric furnace dust after zinc removal provided by the present invention, with reference to specific embodiments.

[0047] Example 1

[0048] The components and contents of the electric furnace dust after zinc removal in the fluidized bed furnace used in Example 1 are as follows: FeO: 30.4%, CaO: 15.6%, MgO: 9.7%, SiO2: 6.2%, Fe: 21.8%, MnO: 3.3%, ZnO: 5.8%, KCl: 7.1%.

[0049] like Figure 1 As shown in the figure, this embodiment provides a method for recycling electric furnace dust after zinc removal, which specifically includes the following steps:

[0050] S1. 10 kg of dezincified electric furnace dust collected from the lower hopper of the fluidized bed furnace and 1 kg of binder are mixed with a roller mill for 5 minutes until homogeneous, yielding a solid material. The predetermined requirements for the collected dezincified electric furnace dust are: particle size of 70-100 mesh and bulk density of 540-600 kg / m³. 3 Specific surface area ≥1000cm² 2 / g, TFe = 45.4%; the binder is composed of: bentonite 33%, magnesium lignosulfonate 40%, puffed corn starch 17%, and silicon dioxide 10%.

[0051] S2. Add 1 kg of water to the solid material obtained in step S1, and mix again for 6 minutes until uniform to obtain a wet-mixed solid material.

[0052] S3. The wet-mixed solid material is briquetting in a roller briquetting machine to obtain green briquettes; the pressure for briquetting the wet-mixed solid material is 50 MPa.

[0053] S4. The green pellets are shaped and sieved, and the complete green pellets are digested at room temperature for 24 hours. The strength parameters of the digested green pellets are: drop strength of 10 times / 0.5m and compressive strength of 527N / pellet.

[0054] S5. The green pellets treated in step S4 are dried at 200℃ for 3 hours and then solidified to obtain cold-solidified pellets for electric furnaces. The cold-solidified pellets for electric furnaces are added to the molten steel in the electric furnace as a slag-reducing agent. The moisture content of the dried cold-solidified pellets for electric furnaces is <2%. The strength parameters of the dried cold-solidified pellets for electric furnaces are: drop strength of 42 times / 0.5m and compressive strength of 3028N / pellet.

[0055] The chilled pellets for electric furnaces prepared in Example 1 were applied to a 100t electric arc furnace. The steel grade smelted was ordinary carbon steel. The raw materials for electric arc furnace smelting were 50% scrap steel and 50% molten steel. The total iron content in the chilled pellets for electric furnaces was 45.4%.

[0056] To ensure that the slag basicity is above 2.0 during the later stages of electric arc furnace steelmaking, the total slag volume of the electric arc furnace should not be less than 1.5% of the total mass of molten steel, and the amount of slag-forming raw materials added to the electric arc furnace should not be less than 1.5t, so we take 1.6t; we select chilled pellets for electric arc furnaces to replace part of the raw materials added to the electric arc furnace, and the mass percentage of chilled pellets for electric arc furnaces is 50% of the total mass of slag-forming raw materials.

[0057] Based on the steel smelting requirements, the following materials were added to the electric arc furnace: 800 kg of chilled pellets for electric furnace, 550 kg of limestone, 130 kg of silica, 80 kg of dolomite, and 50 kg of pulverized coal; the blowing time was 20 minutes. The materials were weighed according to the above proportions and smelted in the electric arc furnace. The composition of the molten steel after smelting is shown in Table 1.

[0058] Table 1 Composition of molten steel after smelting

[0059]

[0060] The present invention uses dezincified electric furnace dust to prepare chilled pellets for electric furnaces to replace limestone as a raw material for electric furnace steelmaking. This method does not affect the quality of molten steel produced by electric furnaces, and the composition of the molten steel produced by this method meets the smelting standards. At the same time, it reduces the amount of limestone used by 40%. The total iron content in the pellets is >40%, which can effectively recover iron resources. In addition, the high basicity chilled pellets for electric furnaces can reduce the melting point and viscosity of slag, shorten the slag formation time, reduce the energy consumption of electric furnace smelting, and help improve the amount and rate of dephosphorization in electric furnace smelting. It is a relatively economical and environmentally friendly utilization method.

[0061] Examples 2-3

[0062] Examples 2 and 3 respectively provide a method for recycling electric furnace dust after zinc removal. Compared with Example 1, the only difference in Example 2 is the mass of binder added in step S1. In Examples 2 and 3, the mass of binder added is 0.8 kg and 0.9 kg, respectively. The other experimental steps are the same as in Example 1, and will not be repeated here.

[0063] Comparative Examples 1-4

[0064] Comparative Examples 1-4 each provide a method for recycling electric furnace dust after zinc removal. Compared with Example 1, the only difference in Comparative Example 1 is the mass of binder added in step S1. The masses of binder added in Comparative Examples 1-4 are 0 kg, 0.1 kg, 0.7 kg, and 1.3 kg, respectively. The other experimental steps are the same as in Example 1 and will not be repeated here. The experimental results are shown in Table 2.

[0065] Comparative Examples 5-6

[0066] Comparative Examples 5 and 6 respectively provide methods for recycling electric furnace dust after zinc removal. Compared with Example 1, the only difference in Comparative Example 1 is the composition of the binder added in step S1. In Comparative Examples 5 and 6, the binders added are puffed corn starch and bentonite binder, respectively. The other experimental steps are the same as in Example 1 and will not be repeated here. In Comparative Examples 5 and 6, the compressive strength of the green pellets obtained are 411 N / piece and 376 N / piece, respectively; the compressive strength of the dried electric furnace cold-fixed pellets are 2560 N / piece and 2380 N / piece, respectively.

[0067] The experimental results of Examples 1-3 and Comparative Examples 1-4 are shown in Table 2. Comparing Examples 1-3 and Comparative Examples 1-3, it was found that as the content of the composite binder in the dezincification electric furnace dust increased from 0% to 10%, the compressive strength of the chilled pellets for electric furnaces also increased from 643 N / piece to 3028 N / piece. However, as the content of the composite binder in the dezincification electric furnace dust continued to increase to 13%, although the compressive strength of the chilled pellets for electric furnaces continued to increase, the existing strength already met the process strength requirements. Adding additional composite binder would undoubtedly increase the cost burden on the industry. However, the compressive strength of the chilled pellets for electric furnaces prepared with too little composite binder did not meet the standards.

[0068] Comparing Example 1 and Comparative Examples 5-6, it can be seen that, under the condition of using the same amount of binder, adding the composite binder to the dezincified electric furnace dust results in a higher compressive strength for the cold-set pellets used in electric furnaces. This means that high-compressive-strength cold-set pellets for electric furnaces can be obtained using a smaller amount of composite binder.

[0069] Table 2. Process parameter settings for Examples 1-3 and Comparative Examples 1-4

[0070]

[0071] In summary, the method for recycling electric furnace dust after zinc removal provided by this invention involves adding a composite binder and water to the electric furnace dust after zinc removal in a fluidized bed furnace, forming it into green pellets under certain pressure, and then sequentially digesting, drying, and solidifying it to obtain cold-solidified pellets for electric furnaces. These pellets are then added to the molten steel in the electric furnace along with the slag. This not only recovers the abundant iron resources but also reduces the amount of limestone used in electric furnace steelmaking, lowering production costs. Simultaneously, these high-basicity cold-solidified pellets for electric furnaces lower the melting point and viscosity of the slag, allowing them to be used as oxidants, slag removers, and temperature regulators in the electric furnace steelmaking process. This shortens the slag removal time, reduces energy consumption in electric furnace smelting, and helps improve the amount and rate of dephosphorization in electric furnace smelting, thus improving the quality of the molten steel. Furthermore, because the electric furnace dust particles after zinc removal in the fluidized bed furnace have a small particle size, the processing is simple and the recycling cost is low. Moreover, the required strength for electric furnace steelmaking pellets can be achieved without high-temperature roasting, resulting in a short production cycle and low production cost. The electric furnace dust used in this invention, after zinc removal in a fluidized bed furnace, contains a higher concentration of active CaO, resulting in better pelletizing properties compared to other electric furnace dust. Under the same conditions, it requires less binder, reducing binder usage and production costs. Furthermore, the composite binder used has minimal impact on the steel composition, which is beneficial for the electric furnace steelmaking process. This virtuous cycle of electric furnace dust—from the electric furnace to the electric furnace dust removal system back to the electric furnace—not only solves the pollution problem caused by the stockpiling of electric furnace dust after zinc removal but also achieves the recycling of metallurgical resources. It aligns with the concept of green production and represents an economical and environmentally friendly utilization method, as well as an essential path for the high-value recycling of metallurgical resources from electric furnace dust in the future.

[0072] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for recycling electric furnace dust after dezincing, characterized by, The method comprises the following steps: S1, mixing the de-zinced electric furnace dust collected according to predetermined requirements with a binder in a predetermined mass ratio to obtain a solid material; S2, adding a predetermined amount of water to the solid material obtained in step S1 and mixing again to obtain a wet mixed solid material; S3, pressing the wet mixed solid material to obtain green balls; S4, shaping and screening the green balls, and digesting the complete green balls at room temperature for a predetermined time; S5, drying and solidifying the green balls treated in step S4 to obtain cold-bonded pellets for electric furnaces; the cold-bonded pellets for electric furnaces are added into electric furnace liquid steel as slagging agent together with electric furnace slag materials.

2. The method according to claim 1, wherein: The de-zinced electric furnace dust in step S1 is the de-zinced electric furnace dust from a fluidized bed; the components and contents of the de-zinced electric furnace dust from a fluidized bed are as follows: FeO: 24-33%, CaO: 12-16%, MgO: 9-11%, SiO2: 5-7%, Fe: 18-24%, MnO: 2-5%, ZnO: 2-7%, and KCl: 5-8%.

3. The method according to claim 2, wherein: The predetermined mass ratio in step S1 is de-zinced electric furnace dust: binder = 90-100: 7-10; and the mixing time is 2-5 min.

4. The method of claim 1, wherein: The predetermined amount of water in step S2 is 9-12% of the mass of the solid material; and the mixing time is 4-6 min.

5. The method of claim 1, wherein: The pressure for pressing the wet mixed solid material in step S3 is 40-60 MPa.

6. The method of claim 1, wherein: The predetermined digestion time in step S4 is 22-26 h.

7. The method of claim 1, wherein: The predetermined requirements of the de-zincified electric furnace dust collected in step S1 are: particle size of 70-100 mesh, bulk density of 540-600 kg / m 3 , specific surface area ≥ 1000 cm 2 / g, TFe > 40%.

8. The method of claim 3, wherein the de-zincing post-electric furnace dust recycling method is characterized by: The composition of the binder in step S1 is as follows: bentonite 25-38%, magnesium lignosulfonate 22-35%, expanded corn starch 13-26%, and silicon dioxide 10-25%.

9. The method of claim 6, wherein the dezinced EAF dust is recovered and utilized as a fluxing agent in the production of a molten iron. The green balls after digestion in step S4 have the following strength parameters: drop strength > 8.5 times / 0.5 m, and compressive strength ≥ 420 N / piece.

10. The method of claim 1, wherein: The drying temperature in step S5 is 150-200°C, and the drying time is 2-4 h; the water content of the cold-bonded pellets for electric furnaces after drying is < 2%; and the cold-bonded pellets for electric furnaces have the following strength parameters: drop strength > 35 times / 0.5 m, and compressive strength ≥ 2500 N / piece.

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