Process for extracting valuable elements from steel plant blast furnace bag dust

Abstract

The present application relates to the technical field of mineral processing, and proposes a valuable element extraction process for blast furnace bag dust of a steel plant, comprising the following process: raw material crushing, carbon powder flotation of the crushed material through a flotation machine, tailings generated in the carbon powder flotation process of the flotation machine into a magnetic separator, slurry containing iron powder selected by the magnetic separator, the slurry pumped into a fifth cyclone, the slurry with iron powder in the fifth cyclone further through stirring and vacuum filtration to obtain iron powder, sulfuric acid is added during stirring for pickling, evaporation to obtain zinc sulfate, and through cyclic separation, carbon powder and iron powder can be separated multiple times, and sodium chloride, potassium chloride and rubidium chloride can be further separated in the overflow solution of the above substances. Through the above technical scheme, the technical problem of low yield and type of the extracted material in the blast furnace bag dust of the steel plant in the related art is solved.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, specifically to a process for extracting valuable elements from blast furnace baghouse dust in steel plants. Background Technology

[0002] The steel industry traditionally uses rotary kilns for high-temperature combustion to process iron-containing dust and sludge. This not only generates pollutants but also wastes recyclable materials such as iron and carbon in the dust, which is not conducive to energy conservation.

[0003] The sorting process can extract valuable elements from dust collector ash, but the existing sorting process is not thorough. It can only extract valuable elements from the dust collector ash, but the extraction rate is not high. A large number of valuable elements remain in the tailings, resulting in waste.

[0004] Patent CN 113333145 B discloses a bag filter dust separation process that can separate and recover dust, producing carbon, iron, zinc, tailings, and salt. Through localized cyclic separation, the yield of the extract is significantly increased. However, there is still room for improvement in the separation process of this patent, to further increase the yield of the extract and the variety of recovered materials. Summary of the Invention

[0005] This invention proposes a process for extracting valuable elements from blast furnace bag filter dust in steel plants, which solves the technical problems of low yield and variety of extracts from blast furnace bag filter dust in related technologies.

[0006] The technical solution of the present invention is as follows:

[0007] The process for extracting valuable elements from blast furnace baghouse dust in steel plants includes the following steps:

[0008] A. Raw material crushing: The material is put into the hopper and fed into the crushing equipment for crushing;

[0009] B. Primary separation of carbon powder: The crushed material is floated to obtain a carbon powder-containing slurry through a flotation machine. The carbon powder-containing slurry is then stirred and vacuum filtered to obtain carbon powder.

[0010] C. Primary separation of iron powder: The tailings generated during the flotation of carbon powder in step B enter the magnetic separator. The magnetic separator separates the slurry containing iron powder, which is then pumped into the fifth hydrocyclone. The slurry containing iron powder in the fifth hydrocyclone is then stirred and vacuum filtered to obtain iron powder.

[0011] D. Primary sorting of zinc sulfate: In steps B and C, sulfuric acid is added during stirring for acid washing. The filtrates produced after vacuum filtration in steps B and C are evaporated in an evaporator to obtain zinc sulfate.

[0012] E. Secondary Separation of Carbon Powder: The tailings generated during the magnetic separation of iron powder in step C are pumped into the first hydrocyclone. The overflow from the first hydrocyclone is pumped into the second hydrocyclone. The diameter of the second hydrocyclone is smaller than that of the first hydrocyclone. The overflow generated by the second hydrocyclone enters the foam separation box. The separated foam enters the flotation machine in step B to participate in the flotation of carbon powder in step B.

[0013] F. Three-stage separation of carbon powder: The underflow from the first hydrocyclone in step E enters the high-frequency screen. The upper portion of the high-frequency screen is pumped into the third hydrocyclone. The diameter of the first hydrocyclone is smaller than that of the third hydrocyclone. The slurry exiting the third hydrocyclone enters the spiral chute, which divides the slurry into three parts. The lightest tailings are returned to step B and merged with the carbon powder-containing slurry from the flotation in step B.

[0014] G. Secondary separation of iron powder: The heaviest slurry from the three parts of slurry produced by the spiral chute in step F is combined with the slurry containing iron powder separated by the magnetic separator in step C.

[0015] H. Three-stage separation of iron powder: The undersize portion of the high-frequency screen in step F is pumped into the fourth hydrocyclone. The overflow of the fourth hydrocyclone is pumped into the first hydrocyclone. The diameter of the second hydrocyclone is smaller than that of the fourth hydrocyclone. The undersize sand from the fourth hydrocyclone enters the gravity separator. The gravity separator divides the slurry into four parts. The heaviest slurry is combined with the slurry containing iron powder separated by the magnetic separator in step C.

[0016] I. Sorting Tailings: The overflow from the foam separation tank in step E enters the thickening tank. The underflow from the thickening tank is pumped into a horizontal screw centrifuge. The filtrate produced by the horizontal screw centrifuge is returned to the thickening tank. The slurry produced by the horizontal screw centrifuge is filtered by stirring to obtain tailings.

[0017] J. Salt Sorting: The overflow from the thickening tank in step I enters the circulating water tank. The circulating water in the circulating water tank is filtered and evaporated through a filter and an evaporator. The resulting solid enters a high-temperature reactor and a first centrifuge to separate sodium chloride. It then enters a low-temperature reactor and a second centrifuge to obtain potassium chloride. After adding an ion exchanger, rubidium chloride is obtained. The remaining mother liquor is returned to the evaporator for recycling and sorting.

[0018] As a further technical solution, step A, cyclic crushing and sorting, is also included:

[0019] The flotation machine in step B has two parts. The tailings from the primary flotation machine enter the magnetic separator in step C. The slurry containing carbon powder floated out by the primary flotation machine enters the secondary flotation machine. The slurry containing carbon powder floated out by the secondary flotation machine is then stirred and vacuum filtered to obtain carbon powder. The tailings from the secondary flotation machine are returned to step A for re-crushing.

[0020] The overflow generated by the third hydrocyclone in step F is returned to step A for re-crushing.

[0021] As a further technical solution, the cyclic sorting of the first hydrocyclone in step E is also included:

[0022] The sediment produced by the second hydrocyclone in step E is returned to the first hydrocyclone in step E.

[0023] The overflow generated by the fourth hydrocyclone in step H and the medium tailings generated by the gravity separator in step H are returned to the first hydrocyclone in step E.

[0024] The filtration in step B is a two-stage filtration process. After the carbon-containing slurry is floated out by the flotation machine, it enters the first-stage vacuum filter. The filtrate from the first-stage vacuum filter is returned to the first hydrocyclone in step E. The carbon-containing slurry produced by the first-stage vacuum filter enters the mixing tank and the second-stage vacuum filter to obtain the carbon powder.

[0025] The filtration in step C is a two-stage filtration process. The fifth hydrocyclone produces a slurry containing iron powder, which enters a first-stage vacuum filter. The filtrate from the first-stage vacuum filter is returned to the first hydrocyclone in step E. The slurry containing iron powder produced by the first-stage vacuum filter then enters a mixing tank and a second-stage vacuum filter to obtain iron powder.

[0026] The middlings produced by the spiral chute in step F are returned to the first hydrocyclone in step E.

[0027] As a further technical solution, the cyclic sorting of the third hydrocyclone in step F is also included:

[0028] The tailings generated by the gravity separator in step H are pumped into the third hydrocyclone.

[0029] As a further technical solution, the cyclic sorting of the fourth hydrocyclone in step H is also included:

[0030] The middlings produced by the gravity separator in step H are pumped into the fourth hydrocyclone.

[0031] The overflow generated by the fifth hydrocyclone in step C enters the sixth hydrocyclone, the underflow generated by the sixth hydrocyclone is pumped back into the fifth hydrocyclone, and the overflow generated by the sixth hydrocyclone is pumped into the fourth hydrocyclone.

[0032] As a further technical solution, it also includes:

[0033] K. Secondary separation of zinc sulfate: The filtrate obtained after stirring and filtering in step I is combined with the filtrate in step D and flows into the evaporator together.

[0034] As a further technical solution, it also includes:

[0035] L. Recovering distilled water: The distilled water produced by the evaporator in step D and the distilled water produced by the evaporator in step J are collected in the distilled water tank, which supplies water for the entire process.

[0036] As a further technical solution, step A involves crushing the raw materials using a hydraulic crushing chamber.

[0037] The working principle and beneficial effects of this invention are as follows:

[0038] 1. This invention uses a hydraulic crushing box to replace the ball mill, which is energy-saving and highly efficient. The dust itself has a low particle size. In order to prevent dust from being stirred up, water is sprayed. Since the dust contains calcium, it forms particles and agglomerates after being sprayed with water. The original ball mill is designed to grind large particles, and grinding the dust is energy-intensive and inefficient. This invention solves this technical problem well by using a hydraulic crushing box.

[0039] 2. This invention adds a foam separation box to increase carbon recovery. Carbon is relatively lightweight, and in actual work, it has been found that foam contains carbon. In order to further recover carbon, the overflow of the second hydrocyclone flows into the foam separation box to further recover the foam and recover carbon from the foam.

[0040] 3. This invention uses a high-frequency screen to separate the oversize and undersize materials. The oversize material is separated by a spiral chute, primarily separating iron and carbon, resulting in better separation. In practical work, it was found that hydrocyclones are more effective at separating particles of 60-300 mesh, while spiral chutes are more effective at separating particles of 20-60 mesh. Based on this, the underflow from the first hydrocyclone flows into the high-frequency screen, where the oversize and undersize materials are separated, thus achieving more precise sorting and resulting in better separation and higher purity of various elements in the dust.

[0041] 4. The process of this invention enables the recovery of rubidium chloride from the final recycled material, providing an additional product compared to other existing sorting processes. Furthermore, a specific recovery order is set based on the specific recovery conditions of sodium chloride, potassium chloride, and rubidium chloride. Since the evaporation is high-temperature evaporation, sodium chloride is recovered first. After the recovery of sodium chloride, potassium chloride, and rubidium chloride, these elements are reduced in the tailings, allowing the tailings to be further utilized by cement plants. Attached Figure Description

[0042] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0043] Figure 1 This is a schematic diagram of the process flow in this invention;

[0044] Figure 2 This is a schematic diagram of the distilled water recovery process in this invention; Detailed Implementation

[0045] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0046] Example 1

[0047] like Figure 1 As shown, in order to solve the technical problem of low yield and variety of extracts from blast furnace bag filter dust in steel plants in related technologies, this embodiment proposes a process for extracting valuable elements from blast furnace bag filter dust in steel plants, including the following process steps:

[0048] A. Raw material crushing: The material is placed into the hopper and fed into the crushing equipment by the feeder. In this embodiment, a hydraulic crushing chamber is selected as the crushing equipment to achieve the crushing of the raw materials.

[0049] B. Primary separation of carbon powder: The crushed material is floated to obtain a carbon powder-containing slurry through a flotation machine. The carbon powder-containing slurry is then stirred and vacuum filtered to obtain carbon powder.

[0050] C. Primary separation of iron powder: The tailings generated during the flotation of carbon powder in step B enter the magnetic separator. The magnetic separator separates the slurry containing iron powder, which is then pumped into the fifth hydrocyclone. The fifth hydrocyclone has a diameter of 150 mm. The slurry containing iron powder in the fifth hydrocyclone is then stirred and vacuum filtered to obtain iron powder.

[0051] D. Primary sorting of zinc sulfate: In steps B and C, sulfuric acid is added during stirring for acid washing. The filtrates produced after vacuum filtration in steps B and C are evaporated in an evaporator to obtain zinc sulfate.

[0052] E. Secondary Separation of Carbon Powder: The tailings generated during the magnetic separation of iron powder in step C are pumped into the first hydrocyclone. The overflow from the first hydrocyclone is pumped into the second hydrocyclone. The second hydrocyclone has a diameter of 75 mm, and the first hydrocyclone has a diameter of 150 mm. The overflow from the second hydrocyclone enters the foam separation tank. The separated foam enters the flotation machine in step B to participate in the flotation of carbon powder in step B.

[0053] F. Three-stage separation of carbon powder: The underflow from the first hydrocyclone in step E enters the high-frequency screen. The upper portion of the high-frequency screen is pumped into the third hydrocyclone, which has a diameter of 250 mm. The diameter of the first hydrocyclone is smaller than that of the third hydrocyclone. The slurry exiting the third hydrocyclone enters the spiral chute, which divides the slurry into three parts. The lightest tailings are returned to step B and merged with the carbon powder-containing slurry from the flotation in step B.

[0054] G. Secondary separation of iron powder: The heaviest slurry from the three parts of slurry produced by the spiral chute in step F is combined with the slurry containing iron powder separated by the magnetic separator in step C.

[0055] H. Three-stage separation of iron powder: The undersize portion of the high-frequency screen in step F is pumped into the fourth hydrocyclone, which has a diameter of 150mm. The overflow from the fourth hydrocyclone is pumped into the first hydrocyclone. The second hydrocyclone has a smaller diameter than the fourth hydrocyclone. The undersize from the fourth hydrocyclone enters the gravity separator, which divides the slurry into four parts. The heaviest part of the slurry is combined with the slurry containing iron powder separated by the magnetic separator in step C.

[0056] I. Sorting Tailings: The overflow from the foam separation tank in step E enters the thickening tank. The underflow from the thickening tank is pumped into a horizontal screw centrifuge. The filtrate produced by the horizontal screw centrifuge is returned to the thickening tank. The slurry produced by the horizontal screw centrifuge is filtered by stirring to obtain tailings.

[0057] J. Salt Sorting: The overflow from the thickening tank in step I enters the circulating water tank. The circulating water in the circulating water tank is filtered and evaporated through a filter and an evaporator. The resulting solid enters a high-temperature reactor and a first centrifuge to separate sodium chloride. It then enters a low-temperature reactor and a second centrifuge to obtain potassium chloride. After adding an ion exchanger, rubidium chloride is obtained. The ion exchanger is zeolite. The remaining mother liquor is returned to the evaporator for recycling and sorting.

[0058] As a further technical solution, step A, cyclic crushing and sorting, is also included:

[0059] The flotation machine in step B has two parts. The tailings from the primary flotation machine enter the magnetic separator in step C. The slurry containing carbon powder floated out by the primary flotation machine enters the secondary flotation machine. The slurry containing carbon powder floated out by the secondary flotation machine is then stirred and vacuum filtered to obtain carbon powder. The tailings from the secondary flotation machine are returned to step A for re-crushing.

[0060] The overflow generated by the third hydrocyclone in step F is returned to step A for re-crushing.

[0061] As a further technical solution, the cyclic sorting of the first hydrocyclone in step E is also included:

[0062] The sediment produced by the second hydrocyclone in step E is returned to the first hydrocyclone in step E.

[0063] The overflow generated by the fourth hydrocyclone in step H and the medium tailings generated by the gravity separator in step H are returned to the first hydrocyclone in step E.

[0064] The filtration in step B is a two-stage filtration process. After the carbon-containing slurry is floated out by the flotation machine, it enters the first-stage vacuum filter. The filtrate from the first-stage vacuum filter is returned to the first hydrocyclone in step E. The carbon-containing slurry produced by the first-stage vacuum filter enters the mixing tank and the second-stage vacuum filter to obtain the carbon powder.

[0065] The filtration in step C is a two-stage filtration process. The fifth hydrocyclone produces a slurry containing iron powder, which enters a first-stage vacuum filter. The filtrate from the first-stage vacuum filter is returned to the first hydrocyclone in step E. The slurry containing iron powder produced by the first-stage vacuum filter then enters a mixing tank and a second-stage vacuum filter to obtain iron powder.

[0066] The middlings produced by the spiral chute in step F are returned to the first hydrocyclone in step E.

[0067] As a further technical solution, the cyclic sorting of the third hydrocyclone in step F is also included:

[0068] The tailings generated by the gravity separator in step H are pumped into the third hydrocyclone.

[0069] As a further technical solution, the cyclic sorting of the fourth hydrocyclone in step H is also included:

[0070] The middlings produced by the gravity separator in step H are pumped into the fourth hydrocyclone.

[0071] The overflow generated by the fifth hydrocyclone in step C enters the sixth hydrocyclone, the underflow generated by the sixth hydrocyclone is pumped back into the fifth hydrocyclone, and the overflow generated by the sixth hydrocyclone is pumped into the fourth hydrocyclone.

[0072] As a further technical solution, it also includes:

[0073] K. Secondary separation of zinc sulfate: The filtrate obtained after stirring and filtering in step I is combined with the filtrate in step D and flows into the evaporator together.

[0074] The process described in this embodiment has the following advantages:

[0075] 1. In this embodiment, a hydraulic crushing box is used to replace the ball mill, which is energy-saving and highly efficient. The dust itself has a low particle size. In order to prevent dust from being stirred up, water is sprayed. Since the dust contains calcium, it forms particles and agglomerates after being sprayed with water. The original ball mill is for grinding large particles, and grinding dust is energy-intensive and inefficient. This embodiment solves this technical problem well by using a hydraulic crushing box.

[0076] 2. This embodiment adds a foam separation box to increase carbon recovery. Carbon is relatively light, and in actual work, it has been found that foam contains carbon. In order to further recover carbon, the overflow of the second hydrocyclone flows into the foam separation box to further recover the foam and recover carbon from the foam.

[0077] 3. In this embodiment, a high-frequency screen is used to separate the oversize and undersize materials. The oversize material is separated by a spiral chute, mainly separating iron and carbon, resulting in better separation. In actual work, it was found that hydrocyclones are more effective at separating particles of 60-300 mesh, while spiral chutes are more effective at separating particles of 20-60 mesh. Based on this, it was found that the underflow from the first hydrocyclone flows into the high-frequency screen, where the oversize and undersize materials are separated, thus achieving more precise sorting and resulting in better separation and higher purity of various elements in the dust.

[0078] 4. The process in this embodiment enables the recovery of rubidium chloride from the final recycled material, providing an additional product compared to other existing sorting processes. Furthermore, a specific recovery order is set based on the specific recovery conditions of sodium chloride, potassium chloride, and rubidium chloride. Since the evaporation is high-temperature evaporation, sodium chloride is recovered first. After the recovery of sodium chloride, potassium chloride, and rubidium chloride, these elements are reduced in the tailings, allowing the tailings to be further utilized by cement plants.

[0079] Example 2

[0080] like Figure 2 As shown, in order to further realize the recycling of water resources, this embodiment, based on embodiment 1, further includes, as a further technical solution:

[0081] L. Recovering distilled water: The distilled water produced by the evaporator in step D and the distilled water produced by the evaporator in step J are collected in the distilled water tank, which supplies water for the entire process.

[0082] Furthermore, for locations requiring clean water in the entire process, such as magnetic separators, flotation machines, high-frequency screens, slurry pumps, spiral chutes, mixing tanks, and gravity separators, pipelines connecting to a distillation water tank can be installed, with the distillation water tank supplying water to these devices.

[0083] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for extracting valuable elements from steel plant blast furnace bag house dust, characterized in that, The process comprises the following steps: A, raw material crushing: the material is put into a bin and enters a crushing device through a feeder for crushing; B, primary separation of carbon powder: the crushed material is subjected to flotation by a flotation machine to obtain a slurry containing carbon powder, which is then stirred and vacuum filtered to obtain carbon powder; C, primary separation of iron powder: the tailings produced in the process of floating carbon powder in step B are subjected to magnetic separation to obtain a slurry containing iron powder, which is then pumped into a fifth cyclone, and the slurry containing iron powder in the fifth cyclone is stirred and vacuum filtered to obtain iron powder; D, primary separation of zinc sulfate: sulfuric acid is added during stirring in steps B and C for acid pickling, and the filtrate produced after vacuum filtration in steps B and C is subjected to evaporation by an evaporator to obtain zinc sulfate; E, secondary separation of carbon powder: the tailings produced in the process of separating iron powder in step C are pumped into a first cyclone, the overflow of the first cyclone is pumped into a second cyclone, the diameter of the second cyclone is smaller than that of the first cyclone, the overflow of the second cyclone is introduced into a froth separation tank, the separated froth is introduced into the flotation machine in step B to participate in the flotation of carbon powder in step B; F, tertiary separation of carbon powder: the underflow of the first cyclone in step E is introduced into a high-frequency screen, the overflow of the high-frequency screen is pumped into a third cyclone, the diameter of the first cyclone is smaller than that of the third cyclone, the slurry discharged from the third cyclone is introduced into a spiral chute, the spiral chute divides the slurry into three parts, and the lightest tailings are returned to step B to be combined with the slurry containing carbon powder floated in step B; G, secondary separation of iron powder: the heaviest slurry of the three parts of slurry produced by the spiral chute in step F is combined with the slurry containing iron powder selected by the magnetic separator in step C; H, tertiary separation of iron powder: the underflow of the high-frequency screen in step F is pumped into a fourth cyclone, the overflow of the fourth cyclone is pumped into the first cyclone, the diameter of the second cyclone is smaller than that of the fourth cyclone, the sand in the fourth cyclone is introduced into a gravity separator, and the heaviest slurry of the four parts of slurry separated by the gravity separator is combined with the slurry containing iron powder selected by the magnetic separator in step C; I, separation of tailings: the overflow of the froth separation tank in step E is introduced into a thickener, the underflow of the thickener is pumped into a horizontal screw centrifuge, the filtrate produced by the horizontal screw centrifuge is returned to the thickener, the slurry produced by the horizontal screw centrifuge is stirred and filtered to obtain tailings; J, separation of salts: the overflow of the thickener in step I is introduced into a circulating water tank, the circulating water in the circulating water tank is filtered and evaporated by a filter and an evaporator, the obtained solid is introduced into a high-temperature reaction kettle and a first centrifuge to separate sodium chloride, then introduced into a low-temperature reaction kettle and a second centrifuge to obtain potassium chloride, then introduced into an ion exchanger to obtain rubidium chloride, and the remaining mother liquor is returned to the evaporator for recycling and separation.

2. The steel plant blast furnace bag house dust valuable element extraction process as claimed in claim 1 wherein, The process further comprises the following steps: A, the crushed material is returned to step A for recycling and crushing; B, the flotation machine in step B has two, the tailings of the primary flotation machine are introduced into the magnetic separator in step C, the slurry containing carbon powder floated by the primary flotation machine is introduced into the secondary flotation machine, the slurry containing carbon powder floated by the secondary flotation machine is stirred and vacuum filtered to obtain carbon powder, and the tailings of the secondary flotation machine are returned to step A for re-crushing; F, the overflow of the third cyclone in step F is returned to step A for re-crushing.

3. The steel plant blast furnace bag house dust valuable element extraction process as claimed in claim 2 wherein, Also included is the recycle of the first cyclone in Step E: The overflow from the second cyclone in Step E is returned to the first cyclone in Step E; The overflow from the fourth cyclone in Step H and the middling from the reclaimer in Step H are returned to the first cyclone in Step E; The filtration in Step B is two-stage filtration, the slurry containing carbon powder from the flotation machine is fed into the first-stage vacuum filter, the filtrate from the first-stage vacuum filter is returned to the first cyclone in Step E, the slurry containing carbon powder from the first-stage vacuum filter is fed into the agitator tank and the second-stage vacuum filter, and then the carbon powder is obtained, The filtration in Step C is two-stage filtration, the slurry containing iron powder from the fifth cyclone is fed into the first-stage vacuum filter, the filtrate from the first-stage vacuum filter is returned to the first cyclone in Step E, the slurry containing iron powder from the first-stage vacuum filter is fed into the agitator tank and the second-stage vacuum filter, and then the iron powder is obtained, The middling from the spiral chute in Step F is returned to the first cyclone in Step E.

4. The steel plant blast furnace bag house dust valuable element extraction process as claimed in claim 3 wherein, Also included is the recycle of the third cyclone in Step F: The tailings from the reclaimer in Step H are pumped into the third cyclone.

5. The steel plant blast furnace bag house dust valuable element extraction process as claimed in claim 4 wherein, Also included is the recycle of the fourth cyclone in Step H: The middling from the reclaimer in Step H is pumped into the fourth cyclone, The overflow from the fifth cyclone in Step C is fed into the sixth cyclone, the underflow from the sixth cyclone is re-pumped into the fifth cyclone, and the overflow from the sixth cyclone is pumped into the fourth cyclone.

6. The steel plant blast furnace bag house dust valuable element extraction process as claimed in claim 5 wherein, Also included are: K. Secondary zinc sulfate separation: the filtrate obtained after agitation and filtration in Step I is combined with the filtrate in Step D, and they are jointly fed into the evaporator.

7. The steel plant blast furnace bag house dust valuable element extraction process as claimed in claim 1 wherein, Also included are: L. Recovery of distilled water: the distilled water produced by the evaporator in Step D and the distilled water produced by the evaporator in Step J are collected in the distilled water tank, which provides water for the entire process.

8. The steel plant blast furnace bag house dust valuable element extraction process as claimed in claim 1 wherein, The raw material is crushed by a hydraulic pressure crushing box in Step A.

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