Magnetic control green hydrogen flash reduction magnetite smelting device and use method

Abstract

A magnetic control green hydrogen flash reduction magnetite smelting device comprises a magnetic controller, a powder bin is arranged outside an inner cavity of a reaction tower, a round pipe at the bottom of the powder bin penetrates through a round hole in the center of a ball bearing neck bush of the magnetic controller, the magnetic controller comprises a plurality of sector-ring-shaped permanent magnets, the permanent magnets are distributed on a supporting disc in an annular array mode, and the intervals between every two adjacent permanent magnets are the same. The speed reduction motor drives the permanent magnet to rotate at a constant speed, magnetite concentrate powder falling into the powder bin and with the particle size smaller than 200 meshes is driven to rotate at a constant speed around the central axis of a round pipe at the bottom of the powder bin, the space stroke of the ore powder 1.0 m away from the bottom face of the permanent magnet in an inner cavity of the tower is prolonged, and the smelting temperature ranges from 1100 DEG C to 1200 DEG C. The invention can be used for flash smelting of magnetite concentrate powder. High-strength smelting is achieved, the green hydrogen utilization rate exceeds 90%, the energy efficiency and carbon efficiency index is advanced, and a coke smelting blast furnace device which is a key management object of a national two-high project can be avoided.

Description

Technical Field

[0001] The invention relates to a magnetically controlled green hydrogen flash reduction smelting magnetite device and method for extending the travel distance of magnetite powder with a particle size finer than 200 mesh under a temperature of 1100℃~1200℃, thereby realizing green hydrogen flash reduction smelting and efficient utilization of green hydrogen. It is applicable to flash smelting of magnetite concentrate, green hydrogen reduction smelting of magnetite ore, resource utilization of iron oxide slag powder, and use in the manufacture of sponge iron. Background Technology

[0002] Blast furnace coke ironmaking remains the primary method of pig iron production globally due to its high efficiency, low energy consumption, and strong raw material adaptability. Despite its mature technology and high efficiency, it still suffers from the following major drawbacks: Traditional blast furnace ironmaking consumes a large amount of coke (approximately 600 kg coke / t pig iron), and coke production itself is energy-intensive and highly polluting. my country's blast furnace fuel ratio (coke + pulverized coal) is 50-100 kg / t of molten iron higher than international advanced levels. Each ton of pig iron produces approximately 1.8 tons of CO2, accounting for over 70% of total emissions from the steel industry; carbon capture is costly and not widely adopted. It requires high-grade iron ore, has poor adaptability to low-grade or complex ores, and requires sintering pretreatment, increasing costs. The average lifespan of domestic blast furnaces is only 5-10 years, with frequent hearth erosion and cooling wall damage, resulting in high maintenance costs. The prices of coke and ore fluctuate greatly, and companies may sacrifice environmental protection investment to reduce costs, creating a vicious cycle. For the reasons mentioned above, the coke-fired blast furnaces and non-blast furnace ironmaking units (excluding hydrogen reduction) in the ironmaking (3110) industry have been included in the key management scope of the national "two high" projects (2025 edition). That is, for new and expanded ironmaking projects, the government will strictly approve the investment and construction of blast furnaces and non-blast furnace ironmaking units (excluding hydrogen reduction), requiring that the new and expanded ironmaking units be hydrogen reduction ironmaking units with high efficiency, energy saving, low carbon and environmental protection advantages. Traditional blast furnaces and non-blast furnace ironmaking units (excluding hydrogen reduction) even face the risk of being eliminated.

[0003] The high temperature of coke-fired ironmaking, ranging from 1400℃ to 1450℃, leads to numerous problems, including increased requirements for the temperature resistance of the equipment, increased investment in smelting furnaces, low thermal efficiency, and increased energy consumption. While ironmaking at 1400℃ to 1450℃ can accelerate the reduction rate, the molten surface of the pellets significantly increases thermal resistance, hindering the transfer of heat and reducing gases from the outer shell to the center. Heat becomes excessively concentrated on the surface layer, preventing some of the ore core from contacting the reducing agent and reaching the low temperature, thus hindering reduction. This reduces the smelting intensity and efficiency within the blast furnace cavity, increasing coke consumption and greenhouse gas emissions.

[0004] After crushing and grinding the raw ore, gangue minerals (such as quartz and silicates) are separated, and then dehydration and drying are carried out to produce iron concentrate powder with Fe3O4 as the main component, which is easily magnetized. Green hydrogen is used to directly reduce and smelt magnetite powder to produce sponge iron, with no CO2 emissions throughout the entire process. Hydrogen produced by electrolyzing water using new energy sources such as solar photovoltaic and wind power is called green hydrogen. In the metallurgical industry, green hydrogen can replace traditional fuel reducing agent CO and avoid greenhouse gas emissions. Sponge iron, as a porous iron product produced by direct reduction, has become an indispensable functional material in modern metallurgical industry and water treatment field due to its pure chemical composition, unique physical structure and diverse forms, with large industrial demand. In electric arc furnace steelmaking, it is an ideal substitute for high-quality scrap steel; in powder metallurgy, it is a high-quality raw material for high-purity iron powder; in water treatment systems, it is a highly efficient and economical deoxygenation filter material. The research and development of magnetite powder with a particle size finer than 200 mesh, and the application of magnetically controlled green hydrogen flash reduction smelting magnetite equipment and methods for efficient utilization of green hydrogen and manufacturing sponge iron products at 1100℃~1200℃, can avoid the use of traditional coke reduction blast furnaces (blast furnaces and non-blast furnace equipment), and help advance the iron smelting industry's "30.60" and "dual carbon" target process. Summary of the Invention

[0005] To address the problems of traditional coke ironmaking at temperatures as high as 1400℃~1450℃, significant corrosion of the furnace lining due to melting and slag formation, high investment and maintenance costs of equipment (including blast furnaces and non-blast furnaces) and supporting equipment, and greenhouse gas emissions, this invention designs a magnetically controlled green hydrogen flash reduction smelting magnetite device and its operating method that extends the travel distance of magnetite powder with a particle size finer than 200 mesh under a temperature of 1100℃~1200℃, thereby achieving green hydrogen flash reduction smelting and efficient utilization of green hydrogen.

[0006] The magnetically controlled green hydrogen flash reduction smelting unit for magnetite mainly includes a geared motor, a magnetic controller, a dispersion cone, a green hydrogen injection pipe, a powder silo, and a reaction tower. The reaction tower is an inverted cylindrical shape with a central orifice on the top surface of its inner cavity. This central orifice allows the vertically arranged bottom circular pipe of the powder silo to pass through. The outlet of the bottom circular pipe of the powder silo is the powder silo outlet. The horizontally arranged top plate of the powder silo has a powder inlet, an oxygen inlet, and a central orifice. The central orifice allows the top of the green hydrogen injection pipe to pass through. The powder silo is vertically arranged outside the inner cavity of the tower. The injection pipe passes through the inner cavity of the powder silo. The annular channel between the green hydrogen injection pipe and the bottom circular pipe of the powder silo serves as the air-powder ejection channel. A slender cylindrical upper part of the dispersion cone is arranged inside the green hydrogen injection pipe. The top of the upper cylindrical part of the dispersion cone extends beyond the green hydrogen injection pipe and is welded and fixed to the workshop crossbeam to support the entire weight of the dispersion cone. The lower truncated cone of the dispersion cone is vertically arranged inside the tower cavity, with its smaller base above its larger base. The smaller base of the lower truncated cone, the outlet surface of the green hydrogen injection pipe, the outlet surface of the powder silo, and the tower... The top surface of the inner cavity is coplanar. The bottom circular tube of the powder hopper passes through the central tube hole of the magnetic controller. The magnetic controller mainly consists of numerous fan-shaped annular permanent magnets of equal thickness and a support disk. Gears are set on the edge of the support disk, and a ball bearing is located at the center. The circular hole of the inner bushing of the ball bearing is the central tube hole of the magnetic controller. The inner bushing of the ball bearing is fixed to the outer wall of the bottom circular tube of the powder hopper. The gears mesh with the gears of the geared motor spindle. The support disk has numerous grooves of equal height evenly distributed in a circular array with the center of the inner bushing of the ball bearing as the center. The height of the grooves is equal to the thickness of the permanent magnets. Permanent magnets are placed in the groove. The upper and lower surfaces of the permanent magnets are parallel, and the upper and lower surfaces are coplanar. The upper surface of the permanent magnets is perpendicular to the central axis of the ball bearing inner bushing. The inner and outer arc edges of the permanent magnets are concentric circles. Numerous permanent magnets are evenly distributed in a ring array with the center of the ball bearing inner bushing as the center. The spacing between adjacent permanent magnets is the same. The central axes of the ball bearing inner bushing, the bottom circular pipe of the powder silo, the green hydrogen injection pipe, the dispersion cone, and the inner cavity of the tower are collinear.

[0007] When using a magnetically controlled green hydrogen flash reduction smelting magnetite device, the smelting reducing agent and fuel are green hydrogen, the oxidant introduced into the powder silo is oxygen at 0.4MPa (gauge pressure) to 0.6MPa (gauge pressure), the raw material falling into the powder silo is magnetite powder with a particle size finer than 200 mesh, the geared motor drives the magnetic controller to rotate at a constant speed around the central axis of the circular tube at the bottom of the powder silo, and the temperature inside the tower is controlled within the range of 1100℃ to 1200℃.

[0008] This invention can be used in flash smelting of magnetite concentrate, hydrogen reduction smelting of magnetite ore, resource utilization of iron oxide slag powder, and manufacturing of sponge iron.

[0009] This invention is applicable to the smelting of magnetite powder. The process, equipment, and supporting facilities are simple, with low unit investment. The smelting temperature is reduced from 1400℃~1450℃ to 1100℃~1200℃. The equipment is compact, with extremely fast smelting speed (flash smelting) and high smelting intensity (high utilization rate of the reaction tower's internal space). The green hydrogen utilization rate exceeds 90%. There is no corrosion problem of the equipment lining during molten slag smelting. The equipment produces products with advanced energy efficiency and carbon efficiency indicators. The sponge iron products have uniform quality. It avoids the production of pig iron for steelmaking, molten reduced iron, and pig iron for casting, which are key targets of national "two high" projects, as well as blast furnace and non-blast furnace ironmaking equipment for coke smelting. Attached Figure Description

[0010] Figure 1 A vertical sectional view of a magnetically controlled green hydrogen flash reduction smelting magnetite unit. Figure 2 This is a horizontal sectional view of magnetron 2. Figure 1 In the diagram, 1 is a geared motor, 2 is a magnetic controller, 21 is a permanent magnet, 22 is a support plate, 3 is a dispersion cone, 4 is a green hydrogen injection pipe, 5 is a powder silo, 51 is a powder drop inlet, 52 is an oxygen inlet, and 6 is a reaction tower. Figure 2 In the diagram, 21 is a permanent magnet, 22 is a support disk, 221 is a gear, and 222 is a ball bearing. Detailed Implementation

[0011] The invention will now be further described with reference to the accompanying drawings.

[0012] like Figure 1As shown, the magnetically controlled green hydrogen flash reduction smelting device for magnetite mainly includes a geared motor 1, a magnetic controller 2, a dispersion cone 3, a green hydrogen injection pipe 4, a powder silo 5, and a reaction tower 6. The reaction tower 6 is an inverted cylindrical shape with a central bore on the top surface of its inner cavity, through which the vertically arranged bottom circular pipe of the powder silo 5 passes. The powder silo 5 includes a vertically arranged bottom circular pipe and a horizontally arranged top plate. The outlet of the bottom circular pipe is the outlet of the powder silo 5. The top plate has a powder inlet 51, an oxygen inlet 52, and a central bore, through which the top of the green hydrogen injection pipe 4 passes. The powder silo 5 is vertically arranged outside the inner cavity of the tower. The green hydrogen injection pipe 4 passes through the inner cavity of the powder silo 5. The annular channel between the green hydrogen injection pipe 4 and the bottom circular pipe of the powder silo 5 is the air-powder ejection channel. The upper part of the dispersion cone 3 is arranged in the inner cavity of the green hydrogen injection pipe 4. The dispersion cone 3 comprises a vertically arranged upper cylinder and a vertically arranged lower truncated cone. The top of the upper cylinder extends beyond the green hydrogen injection pipe 4 and is welded and fixed to the workshop crossbeam to support the entire weight of the dispersion cone 3. The lower truncated cone is arranged inside the tower cavity, with its smaller base surface above the larger base surface. The smaller base surface of the lower truncated cone 3, the outlet surface of the green hydrogen injection pipe 4, the outlet surface of the powder silo 5, and the top surface of the tower cavity are coplanar. The bottom circular tube of the powder silo 5 passes through the central tube hole of the magnetron 2. The magnetic controller 2 mainly includes numerous fan-shaped annular permanent magnets 21 of equal thickness and a support disk 22. Gears 221 are arranged at the edges of the support disk 22, and a ball bearing 222 is located at its center. The inner bushing of the ball bearing 222 has a circular hole that serves as the central tube hole of the magnetic controller 2. The inner bushing of the ball bearing 222 is fixed to the outer wall of the bottom circular tube of the powder silo 5. The gears 221 mesh with the main shaft gear of the reduction motor 1. The support disk 22 has numerous grooves of equal height evenly distributed in a circular array centered on the inner bushing of the ball bearing 222. The groove height... The permanent magnet 21 is placed in a groove with the same thickness as the permanent magnet 21. The upper and lower surfaces of the permanent magnet 21 are parallel, and the upper and lower surfaces of the permanent magnet 21 are coplanar. The upper surface of the permanent magnet 21 is perpendicular to the central axis of the inner bushing of the ball bearing 222. The inner and outer arc edges of the permanent magnet 21 are concentric circles. Numerous permanent magnets 21 are evenly distributed in a ring array with the center of the inner bushing of the ball bearing 222 as the center, and the interval between adjacent permanent magnets 21 is the same. The inner bushing of the ball bearing 222, the bottom circular tube of the powder silo 5, the green hydrogen injection pipe 4, the dispersion cone 3, and the central axis of the tower cavity are collinear.

[0013] The geared motor 1 includes a main shaft gear, which is vertically arranged and meshes with the outer edge gear 221 of the support plate 22 of the magnetic controller 2. The magnetic controller 2 rotates uniformly around the central axis of the bottom circular tube of the powder silo 5. Changing the speed of the geared motor 1 can change the speed of the magnetic controller 2. The geared motor 1 can be arranged above or below the magnetic controller 2.

[0014] The magnetic controller 2 includes numerous permanent magnets 21 and a support disk 22. All permanent magnets 21 are fan-shaped and of equal thickness. Gears 221 are located at the edge of the support disk 22, and a ball bearing 222 is located at its center. The inner wall of the inner bushing of the ball bearing 222 is in close contact with and fixedly connected to the outer wall of the bottom circular tube of the powder silo 5, ensuring that the bottom circular tube of the powder silo 5 remains stationary. Driven by the geared motor 1, the magnetic controller 2 can rotate at a constant speed around the central axis of the bottom circular tube of the powder silo 5. The edge gears 221 mesh with the main shaft gear of the geared motor 1. The support disk 22 has numerous grooves arranged in a circular array, with the center of the inner bushing of the ball bearing 222 as the center. The grooves are evenly distributed in a circular array, and their height is equal to the thickness of the permanent magnets 21. The permanent magnets 21 are placed within the grooves. The upper and lower surfaces of the numerous permanent magnets 21 are parallel. The upper and lower surfaces of numerous permanent magnets 21 are coplanar. The upper surface of the permanent magnets 21 is perpendicular to the central axis of the bottom circular tube of the powder silo 5. The inner and outer arc edges of the permanent magnets 21 are concentric circles. The numerous permanent magnets 21 are evenly distributed in a ring array with the center of the inner bushing of the ball bearing 222 as the center. When the magnetic controller 2 rotates around the central axis of the bottom circular tube of the powder silo 5, the permanent magnets 21 placed in the groove of the support plate 22 also rotate uniformly around the central axis of the bottom circular tube of the powder silo 5 at the same speed.

[0015] The dispersion cone 3 comprises a vertically arranged upper cylinder and an upright lower truncated cone. The bottom surface of the upper cylinder and the small bottom surface of the lower truncated cone have the same diameter and are fully welded together. The upper cylinder is fitted inside the green hydrogen injection pipe 4. The central axes of the upper cylinder and the green hydrogen injection pipe 4 are collinear. The top of the upper cylinder passes through the green hydrogen injection pipe 4 and is welded to the workshop crossbeam to support the entire weight of the dispersion cone 3. The top of the dispersion cone 3 is welded and fixed to the workshop crossbeam, while the lower truncated cone is freely suspended in the inner cavity of the tower. The small bottom surface of the lower truncated cone is on top, and the large bottom surface is on the bottom. The small bottom surface of the truncated cone is coplanar with the top surface of the inner cavity of the tower. The truncated cone is arranged in the inner cavity of the tower. The small bottom surface of the lower truncated cone, the outlet surface of the powder silo 5, and the top surface of the inner cavity of the tower are coplanar. The central axes of the dispersion cone 3, the green hydrogen injection pipe 4, and the inner cavity of the tower are collinear.

[0016] The green hydrogen injection pipe 4 is a straight pipe. The upper cylinder of the dispersion cone 3 is arranged inside the green hydrogen injection pipe 4, which is located inside the powder silo 5. The top end of the green hydrogen injection pipe 4 passes through the central hole in the top plate of the powder silo 5, and the bottom end passes through the inner cavity of the bottom circular pipe of the powder silo 5. The outlet surface of the green hydrogen injection pipe 4 is coplanar with the top surface of the tower cavity. The central axes of the green hydrogen injection pipe 4, the powder silo 5, and the reaction tower 6 are collinear.

[0017] The powder silo 5 includes an inverted conical barrel at the top and a vertically arranged circular tube at the bottom. The large base plate of the top conical barrel is on top, and the small bottom opening is at the bottom. The circumference of the small bottom opening and the circumference of the bottom circular tube inlet are fully welded together. The bottom circular tube passes through the central tube hole on the top surface of the inner cavity of the tower, and the outlet surface of the bottom circular tube is coplanar with the top surface of the inner cavity of the tower. The large base plate of the top conical barrel is provided with a powder inlet 51, an oxygen inlet 52, and a central tube hole, through which the top end of the green hydrogen injection pipe 4 passes. The green hydrogen injection pipe 4 vertically passes through the inner cavity of the powder silo 5. The powder silo 5 is located above the top wall of the reaction tower 6, and the central axis of the powder silo 5 and the reaction tower are collinear.

[0018] The reaction tower 6 is shaped like an inverted cylinder, with its inner cavity used for thorough dispersion of the powder and the green hydrogen reduction smelting reaction. A central tube hole is opened on the top surface of the inner cavity, through which the bottom circular tube of the powder silo 5 passes. The outlet surface of the bottom circular tube of the powder silo 5 is coplanar with the top surface of the inner cavity. The top conical cylinder and bottom circular tube of the powder silo 5, the green hydrogen injection pipe 4, the upper cylinder and lower frustum-shaped cone of the dispersion cone 3 are collinear with the centerline of the reaction tower 6.

[0019] The bottom circular tube of powder silo 5 passes through the central hole on the top surface of the tower cavity. The outlet surface of the bottom circular tube is coplanar with the top surface of the tower cavity, and powder silo 5 is located above the top surface of the tower cavity. The top end of the green hydrogen injection pipe 4 passes through the central hole on the top plate of powder silo 5, and the bottom end passes through the inner cavity of the bottom circular tube of powder silo 5. The outlet surface of the green hydrogen injection pipe 4 is coplanar with the top surface of the tower cavity. The upper cylinder of dispersion cone 3 is fitted inside the inner cavity of green hydrogen injection pipe 4. The central axes of the upper cylinder of dispersion cone 3, green hydrogen injection pipe 4, and powder silo 5 are collinear. The bottom end face of the upper cylinder of dispersion cone 3 is fully welded to the small bottom surface of the lower truncated cone. The bottom end face of the upper cylinder, the small bottom surface of the lower truncated cone, and the top surface of the tower cavity are coplanar. The lower truncated cone is located inside the tower cavity. The bottom circular tube of powder silo 5 passes through the bearing inner sleeve, which is fixedly connected to the bottom circular tube of powder silo 5. The permanent magnet 21 is placed in the groove of the support plate 22. The edge gear 221 of the support plate 22 meshes with the main shaft gear of the reduction motor 1. The support plate 22 is perpendicular to the central axis of the bottom circular tube of powder silo 5. The central axes of the bearing inner sleeve, powder silo 5, green hydrogen injection pipe 4, dispersion cone 3 and reaction tower 6 are collinear.

[0020] When using a magnetically controlled green hydrogen flash reduction smelting magnetite device, the smelting reducing agent and fuel are green hydrogen, the oxidant introduced into the powder silo 5 is oxygen at 0.4MPa (gauge pressure) to 0.6MPa (gauge pressure), the powder falling into the powder silo 5 is magnetite powder with a particle size finer than 200 mesh, the reduction motor 1 drives the magnetic controller 2 to rotate at a constant speed around the central axis of the circular tube at the bottom of the powder silo 5, and the temperature inside the tower is controlled within the range of 1100℃ to 1200℃.

[0021] Magnetite powder falls into powder silo 5 through powder inlet 51 via the material seal at the inlet of powder silo 5, and mixes uniformly with oxygen at 0.4MPa (gauge pressure) to 0.6MPa (gauge pressure) introduced from oxygen inlet 52 to form an air-powder gas flow (oxygen + powder). The air-powder gas flow is rapidly injected into the tower cavity through the annular channel between the bottom circular pipe of powder silo 5 and the green hydrogen injection pipe 4. After leaving the bottom circular pipe outlet of powder silo 5, the air-powder gas flow first touches the side wall of the lower truncated cone of dispersion cone 3. Under the guiding effect of the side wall of the lower truncated cone of dispersion cone 3, the air-powder gas flow is deflected to an area outside the center below the center of the top surface of the tower cavity. Driven by reduction motor 1, magnetizer 2 rotates slowly and uniformly, driving numerous permanent magnets 21 to rotate slowly and uniformly around the central axis of powder silo 5. Within the tower cavity space within a vertical distance of 1.0m from the bottom surface of permanent magnet 21, the magnetite powder particles are magnetized and then subjected to the magnetic force of permanent magnet 21. The permanent magnet 21 is fan-shaped, with numerous permanent magnets 21 forming a circular region. Adjacent permanent magnets 21 are spaced at equal intervals, ensuring that during the circular rotation of the magnetic controller 2, the two permanent magnets 21 apply a stable magnetic force to the same mineral powder particle. The circular rotation of the permanent magnet 21 around the central axis of the powder hopper 5 applies a stable tangential magnetic force to the mineral powder, causing the powder to undergo a superimposed circular motion on its original projectile motion under gravity, ultimately resulting in a spiral downward movement along the central axis of the tower's inner cavity. As mineral powder is stably injected into the tower's inner cavity, the powder within the magnetic field of the permanent magnet 21 continuously moves out of this field. The remaining projectile motion of the powder after leaving the magnetic field flows through the tower's inner cavity.

[0022] The greater the amount of ore per unit volume within the tower cavity, the more uniform the ore distribution, the longer the ore powder travel (longer residence time), the faster the smelting speed, the greater the smelting intensity, and the higher the smelting production efficiency. Within the tower cavity space with a vertical distance h ≤ 1.0m from the bottom surface of the permanent magnet 21, the ore powder flows in a spiral pattern. The pitch of the ore powder trajectory depends on the rotation speed of the permanent magnet 21; the faster the permanent magnet 21 rotates, the smaller the ore powder trajectory pitch. Within the tower cavity space with a vertical distance h ≤ 1.0m from the bottom surface of the permanent magnet 21, the spiral flow of the ore powder can increase the ore powder travel in the 1100℃~1200℃ region and prolong the ore powder residence time, improve the ore powder space filling degree, increase the uniformity of ore powder spatial distribution, thereby improving the utilization rate of the tower cavity space, reducing the reaction tower volume and lowering the investment per unit capacity. It also helps to improve the uniformity of ore powder and oxygen mixing and contact, thereby improving the thermodynamic conditions of the subsequent green hydrogen flash reduction smelting reaction.

[0023] Before falling into powder silo 5, the mineral powder passes through a material seal to prevent ambient air from entering the tower cavity. This avoids impurities such as nitrogen affecting the green hydrogen reduction reaction rate within the tower cavity, ensuring that the reduction reaction waste gas is mainly composed of water vapor and hydrogen. This improves the economic efficiency of condensing and recovering the latent heat of water vapor and residual hydrogen (<10%) from the reduction reaction waste gas outside the reaction tower 6. The oxygen introduced into powder silo 5 has a certain pressure, which can improve the flowability of the mineral powder within powder silo 5 and prevent the formation of a material arch at the bottom circular pipe inlet of powder silo 5 due to the reduced cross-sectional area, thus preventing the mineral powder from flowing out of powder silo 5 and into the tower cavity. The lower part of the dispersion cone 3 is designed with a truncated cone body to prevent the mineral powder particles from being excessively concentrated in the central axis area of ​​the tower cavity, and to disperse them in areas outside the center of the tower.

[0024] The permanent magnet 21 is made of permanent magnet material, the support plate 22 is made of non-magnetic material, and the powder silo 5, green hydrogen injection pipe 4, and dispersion cone 3 are all made of magnetically blocking material. After the magnetic blocking effect of the "magnetic permeable layer-insulation layer-refractory layer" on the top wall of the reaction tower 6, the magnetic force of the permanent magnet 21 on the mineral powder in the tower cavity is weakened. The experiment shows that within the tower cavity space where the vertical distance h from the bottom surface of the permanent magnet 21 is ≤ 1.0m, the magnetic force of the permanent magnet 21 on the mineral powder always exists, so much so that it can significantly change the mineral powder's path.

[0025] Green hydrogen molecules have strong diffusion and capillary penetration capabilities. The mineral powder particles injected into the tower cavity are finer than 200 mesh, which significantly expands the surface area of ​​the powder particles, reducing the resistance to lateral diffusion of green hydrogen into the particle group. Furthermore, it reduces the resistance to penetration of green hydrogen into the microscopic capillaries of the powder particles, increasing the likelihood of a complete green hydrogen reduction smelting reaction. The magnetron 2 rotates slowly and uniformly, attracting the mineral powder to move within the tower cavity space at a vertical distance h≤1.0m from the bottom surface of the permanent magnet 21. This optimizes the motion from projectile motion to spiral motion, extending the travel and residence time of the high-temperature powder particles in the green hydrogen environment, creating favorable thermodynamic conditions for a complete green hydrogen reduction smelting reaction. Applications show that achieving green hydrogen flash reduction smelting of magnetite powder increases the primary utilization rate of green hydrogen from 15%–30% in green hydrogen reduction smelting of sinter to over 90%, solving the problems of low primary hydrogen utilization and low smelting efficiency in green hydrogen reduction smelting of spherical sinter.

[0026] When the air-powder gas flow at 0.4MPa (gauge pressure) to 0.6MPa (gauge pressure) leaves the powder silo 5, it mixes with the green hydrogen injected from the green hydrogen injection pipe 4. The "oxygen + green hydrogen + mineral powder" mixed gas flow is injected into the inner cavity of the tower at a certain speed. The mineral powder particle size is finer than 200 mesh. The mineral powder in the "oxygen + green hydrogen + mineral powder" mixed gas flow with the mixed gas flow, and no air-powder separation phenomenon occurs. Near the outlet of powder silo 5, the mixed gas flow of "oxygen + green hydrogen + mineral powder" is ignited and undergoes pure oxygen combustion of green hydrogen. There is an excess of green hydrogen, and the oxygen is completely consumed. The mineral powder and excess green hydrogen absorb part of the heat released by the pure oxygen combustion of green hydrogen, raising the temperature to 1100℃~1200℃. The remaining heat released by the pure oxygen combustion of green hydrogen is absorbed by the remaining green hydrogen reduction smelting reaction. The heat released by the pure oxygen combustion of green hydrogen = the heat absorbed by the magnetite powder and green hydrogen when heated to 1100℃~1200℃ + the heat absorbed by the flash reduction smelting reaction of the remaining green hydrogen, thus establishing the high-temperature environment of 1100℃~1200℃ required for the complete green hydrogen reduction smelting reaction.

[0027] The beneficial effects of using a magnetically controlled green hydrogen flash reduction smelting magnetite powder apparatus include at least the following:

[0028] Directly producing solid powder sponge iron eliminates the need for smelting and slag production, reducing the requirements for high-temperature and corrosion resistance of the equipment lining, extending its service life, and lowering investment costs.

[0029] The green hydrogen flash reduction smelting short-process steelmaking process replaces the traditional sintering-blast furnace melting and slag-making long-process steelmaking process. The raw material is changed from pellets / sintered ore to magnetite powder finer than 200 mesh, avoiding traditional sintering equipment and simplifying the ironmaking process.

[0030] The product, sponge iron, replaces pig iron for steelmaking, molten reduced iron, and pig iron for foundry, which are key targets of the national "two high" projects. The green hydrogen flash reduction ironmaking furnace replaces blast furnaces for coke smelting and non-blast furnace ironmaking equipment, which is in line with the requirements of national industrial policies.

[0031] The smelting temperature was reduced from 1400℃~1450℃ to 1100℃~1200℃, and the mineral powder particles remained in an unmelted solid particle state. The microscopic capillaries of the powder particles were not blocked, thus maintaining the good porous properties of the sponge iron.

[0032] The energy consumed is green electricity and green hydrogen, without consuming coke or emitting greenhouse gases, achieving true "zero" carbon smelting, and the equipment's products have advanced carbon efficiency indicators.

[0033] Green hydrogen reduction flue gas purification replaces desulfurization and denitrification purification with water removal purification, and flue gas waste heat recovery mainly focuses on recovering the latent heat of condensation of flue gas water vapor, thus improving the energy utilization rate of the unit and the advanced energy efficiency indicators of the unit's products.

[0034] Green hydrogen dynamic flash reduction smelting of iron ore powder replaces CO static reduction smelting of pellets / sinter, which speeds up smelting, shortens smelting time, improves smelting intensity per unit volume and utilization rate of tower cavity space, makes smelting reaction more thorough, improves smelting efficiency, and achieves a green hydrogen utilization rate of over 90%.

Claims

1. A magnetically controlled green hydrogen flash reduction smelting device for magnetite mainly includes a geared motor, a magnetic controller, a dispersion cone, a green hydrogen injection pipe, a powder silo, and a reaction tower. The reaction tower is an inverted cylindrical shape with a central tube opening on the top surface of the inner cavity. The central tube opening allows the bottom circular pipe of the vertically arranged powder silo to pass through. The outlet of the bottom circular pipe of the powder silo is the powder silo outlet. The top plate of the horizontally arranged powder silo has a powder inlet, an oxygen inlet, and a central tube opening. The central tube opening allows the top of the green hydrogen injection pipe to pass through. The powder silo is vertically arranged outside the inner cavity of the tower, and the green hydrogen injection pipe passes through the powder silo. The annular channel between the green hydrogen injection pipe and the bottom circular pipe of the powder silo in the inner cavity of the silo serves as the air-powder ejection channel. A slender cylindrical upper part of the dispersion cone is arranged inside the green hydrogen injection pipe. The top of the upper cylindrical part of the dispersion cone extends beyond the green hydrogen injection pipe and is welded and fixed to the workshop crossbeam to support the entire weight of the dispersion cone. The lower truncated cone of the dispersion cone is vertically arranged inside the tower cavity, with its smaller base above its larger base. The smaller base of the lower truncated cone, the outlet surface of the green hydrogen injection pipe, the outlet surface of the powder silo, and the top surface of the tower cavity are coplanar. Its characteristic is that: The bottom circular tube of the powder silo passes through the central tube hole of the magnetic controller. The magnetic controller mainly consists of numerous annular permanent magnets of equal thickness and a support disk. Gears are set on the edge of the support disk, and a ball bearing is located at the center. The circular hole of the inner bushing of the ball bearing is the central tube hole of the magnetic controller. The inner bushing of the ball bearing is fixed to the outer wall of the bottom circular tube of the powder silo. The gears mesh with the gears of the geared motor spindle. The support disk has numerous grooves of equal height evenly distributed in a circular array with the center of the inner bushing of the ball bearing as the center. The height of the grooves is equal to the thickness of the permanent magnets. The grooves contain... A permanent magnet is placed with its upper and lower surfaces parallel, coplanar, and perpendicular to the central axis of the ball bearing inner bushing. The inner and outer arc edges of the permanent magnet are concentric circles. Numerous permanent magnets are evenly distributed in a ring array with the center of the ball bearing inner bushing as the center. The spacing between adjacent permanent magnets is the same. The central axes of the ball bearing inner bushing, the bottom circular pipe of the powder silo, the green hydrogen injection pipe, the dispersion cone, and the inner cavity of the tower are collinear.

2. When using the magnetically controlled green hydrogen flash reduction smelting magnetite apparatus according to claim 1, the smelting reducing agent and fuel are green hydrogen, the oxidant introduced into the powder silo is oxygen at 0.4 MPa (gauge pressure) to 0.6 MPa (gauge pressure), the raw material falling into the powder silo is magnetite powder with a particle size finer than 200 mesh, the geared motor drives the magnetic controller to rotate at a constant speed around the central axis of the circular tube at the bottom of the powder silo, and the temperature inside the tower is controlled in the range of 1100℃ to 1200℃.

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