Intermediate frequency furnace for reducing iron concentrate with hydrogen
By setting multi-directional blowing holes at the bottom and sides of the intermediate frequency furnace, and combining bottom blowing and side blowing modes, the problem of the single direction of hydrogen blowing in the intermediate frequency furnace is solved, and efficient iron concentrate reduction and smelting efficiency are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- INNER MONGOLIA ACADEMY OF SCIENCE & TECHNOLOGY
- Filing Date
- 2025-09-01
- Publication Date
- 2026-07-24
AI Technical Summary
The existing medium-frequency furnaces have a single direction for hydrogen injection, resulting in poor reduction effect and inability to achieve efficient reduction of iron concentrate.
Multiple blowing holes, including bottom blowing holes and side blowing holes, are set at the bottom and sides of the medium frequency furnace body. The blowing angle is 30-50°. Combining bottom blowing and side blowing modes, hydrogen is blown in multiple directions and powdered materials are supplied through a dust collection hood, supporting real-time adjustment of material ratio.
It improves the reduction effect, increases the reaction rate and smelting efficiency, supports precise reduction and slag-forming reaction, and provides a deeper understanding of the reaction mechanism in hydrogen metallurgy.
Smart Images
Figure CN224552047U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of iron concentrate refining equipment, and in particular to a medium-frequency furnace that uses hydrogen to reduce iron concentrate. Background Technology
[0002] Medium-frequency furnaces are crucial induction heating and melting equipment in industrial fields, particularly in metallurgy, casting, and heat treatment. Their core function lies in utilizing the alternating magnetic field generated by medium-frequency alternating current to induce strong eddy currents within the metal charge, thereby generating Joule heat through the metal's own resistance to achieve heating or melting. Currently, medium-frequency furnaces lack reduction capabilities and are not equipped with hydrogen reduction devices; they only perform simple heating and melting, or add reducing agents such as pulverized coal to the molten pool to achieve reduction. Replacing carbon with hydrogen is a key direction for current low-carbon development and energy transformation, and is considered a major driver of greening the steel industry. Hydrogen metallurgy is one of the effective ways to achieve complete low-carbon, green, and sustainable development. Injecting pure hydrogen (or green hydrogen) into the medium-frequency furnace to achieve the reduction melting of iron concentrate / iron ore will achieve zero carbon emissions, and the product can reach high-purity liquid metal levels. However, existing medium-frequency furnaces have drawbacks; the hydrogen is injected from the bottom of the furnace, resulting in a single-direction approach and poor reduction efficiency.
[0003] Therefore, based on the above-mentioned technical problems, it is necessary to provide a medium-frequency furnace for reducing iron concentrate by using hydrogen to inject hydrogen in multiple directions and improve the reduction effect. Utility Model Content
[0004] The purpose of this invention is to overcome the defects of the existing technology and provide a medium-frequency furnace for reducing iron concentrate with hydrogen, which solves the problem of poor reduction effect due to the single direction of hydrogen injection in the medium-frequency furnace.
[0005] To achieve the above objectives, this utility model provides the following technical solution:
[0006] This utility model discloses a medium-frequency furnace for reducing iron concentrate with hydrogen, comprising:
[0007] Furnace body, dust collection hood installed on top of the furnace body; and
[0008] The base is located at the bottom of the furnace body:
[0009] The dust collection hood is provided with a vertically downward extending material feeding channel, and the bottom of the material feeding channel has a material feeding port. The bottom of the furnace body is provided with a bottom blowing hole, and multiple side blowing holes are evenly distributed around the circumference of the furnace body. The blowing angle of the side blowing holes extends downward at an angle of 30-50° with the horizontal plane.
[0010] Furthermore, the diameter of the side blowing hole is 30-50mm, and the height of the side blowing hole from the furnace bottom is 300-500mm.
[0011] Furthermore, the furnace body has an internal lining, an insulating layer is fixed to the outer wall of the lining, a sensor is installed on the outer layer of the insulating layer, and a cooling copper pipe is installed above the sensor.
[0012] Furthermore, the inner diameter of the furnace lining is 100-300mm and the height is 600-1000mm, and the height of the molten metal liquid level in the molten pool of the furnace lining is 300-500mm.
[0013] Furthermore, the sensor is formed by winding an induction coil, and the outer surface of the induction coil is provided with an insulating protective layer.
[0014] Furthermore, the winding height of the induction coil is 300-500mm.
[0015] Furthermore, the induction coil is a copper tube.
[0016] Furthermore, the bottom of the molten pool in the furnace lining is provided with permeable sand and permeable bricks.
[0017] Furthermore, the dust hood is connected to a rotating arm, the rotating arm has a channel inside that communicates with the interior of the furnace body, and a smoke extractor is installed at the end of the rotating arm.
[0018] Furthermore, it also includes a tilting device, which is connected to one side of the furnace body, and an iron tapping port is provided on the upper part of the furnace body.
[0019] In the above technical solution, the medium-frequency furnace for reducing iron concentrate with hydrogen provided by this utility model has the following advantages:
[0020] The medium-frequency furnace designed in this utility model features bottom-blowing holes and side-blowing holes at the bottom and sides of the furnace body, respectively. This allows for both bottom-blowing and circumferential side-blowing, using different modes of side-blowing and bottom-blowing to inject hydrogen and improve the reduction effect. Furthermore, powdered materials can enter the furnace body through the feeding channel on the dust hood to participate in the reaction. Materials can be added at any time during production to adjust the material ratio, ensuring accurate material reduction and slag-forming reaction. Modifying this medium-frequency furnace helps to gain a deeper understanding of the reaction mechanism of hydrogen metallurgy, improve the reaction rate, and thus increase smelting efficiency. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings.
[0022] Figure 1 This is a schematic diagram of the overall structure of the medium-frequency furnace for reducing iron concentrate using hydrogen, as disclosed in this utility model.
[0023] Explanation of reference numerals in the attached figures:
[0024] 1. Dust hood; 2. Rotating arm; 3. Refractory mortar; 4. Feed port; 5. Iron tapping port; 7. Furnace body; 8. Side-blown hydrogen pipe; 9. Side-blown hole; 10. Induction coil; 11. Insulation layer; 12. Furnace lining; 13. Molten metal; 14. Bottom-blown hydrogen pipe; 15. Bottom-blown hole; 16. Permeable brick; 17. Base; 18. Tilting device; 19. Smoke extractor. Detailed Implementation
[0025] To enable those skilled in the art to better understand the technical solution of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.
[0026] See Figure 1 As shown;
[0027] A utility model discloses a medium-frequency furnace for reducing iron concentrate with hydrogen, comprising: a furnace body 7, with a dust collection hood 1 at the top and a base 17 at the bottom.
[0028] The dust hood 1 is equipped with a vertically downward extending feeding channel, and the bottom of the feeding channel has a feeding port 4. The bottom of the furnace body 7 is provided with a bottom blowing hole 15, and multiple side blowing holes 9 are evenly distributed around the circumference of the furnace body 7. The blowing angle of the side blowing holes 9 extends downward at an angle of 30-50° with the horizontal plane, so that bottom blowing, side blowing, or bottom blowing and side blowing can be selected selectively. By blowing hydrogen through side blowing and bottom blowing in different modes, the reduction effect can be improved. The modification and transformation of this medium frequency furnace will help to understand the reaction mechanism of hydrogen metallurgy, improve the reaction rate, and effectively improve the smelting efficiency.
[0029] Specifically, the upper part of the intermediate frequency furnace is a dust collection hood 1, which efficiently collects dust. The shape and size of the dust collection hood 1 are determined according to the size and shape of the intermediate frequency furnace to ensure that the dust collection hood 1 can completely cover the intermediate frequency furnace and seal it. Sealing material is installed on the contact surface with the furnace body 7 to ensure the sealing performance between the dust collection hood 1 and the furnace body 7, and to prevent the leakage of smoke, hydrogen and exhaust gas.
[0030] Preferably, the inside of the dust hood 1 is lined with refractory mortar 3 to ensure it can withstand high-temperature flue gas. The dust hood 1 is connected to a rotating arm 2, which also has a ventilation function (i.e., a smoke extraction duct). The rotating arm 2 has a channel inside that communicates with the inside of the furnace body 7, and a smoke extractor 19 is installed at the end of the rotating arm 2 through a duct.
[0031] The dust hood 1 is equipped with a vertically downward extending feeding channel, and the end of the feeding channel has a feeding port 4. The feeding port 4 is located in the central area of the dust hood 1. Powdered materials such as mineral powder, coal powder, and calcium oxide powder can enter the furnace body 7 vertically through the feeding channel to participate in the reaction. Materials can be added at any time during the production process to adjust the material ratio, ensure accurate material reduction and slag-forming reaction.
[0032] The furnace body 7 of the medium frequency furnace adopts a steel frame structure and is cooled by circulating water with a cooling water flow rate of ≥10m3 / h.
[0033] The upper part of the furnace body 7 is provided with an iron tapping port 5, which is made of refractory material. The molten iron produced in the furnace body 7 can be poured out through the iron tapping port 5.
[0034] The furnace body 7 has three side blowing holes 9 around its perimeter for side blowing hydrogen injection. The injected hydrogen can be pure hydrogen or hydrogen-containing reducing gas, such as coke oven gas or methane. The side blowing holes 9 are evenly distributed around the furnace body 7. The diameter of the side blowing holes is 30-50 mm, the blowing angle is 30-50° with the horizontal plane, and the height of the side blowing holes is 300-500 mm from the furnace bottom. The side blowing holes 9 are connected to the external hydrogen injection device through the side blowing hydrogen pipe 8.
[0035] The innermost part of the medium-frequency furnace body 7 is the furnace lining 12, with an inner diameter of 100-300mm and a net height of 600-1000mm. The liquid level of the molten metal 13 in the molten pool is 300-500mm. The furnace lining 12 is constructed using refractory materials, with different refractory materials used for the upper and lower parts. The upper part is made of plastic furnace charge with an Al2O3 content ≥70%, which is easy to apply and has high-temperature resistance. The lower part can use conventional furnace lining 12 materials.
[0036] The outer layer of the furnace lining 12 is an insulating layer 11, which is treated with multi-step insulation. The outer layer of the insulating layer 11 is an inductor, and the upper part of the inductor is a cooling copper pipe, which serves to cool the furnace lining 12 and fix the furnace lining 12.
[0037] The inductor is made of induction coil 10, which is made of T2 high-purity copper tube. The outer surface of the coil is covered with an insulating protective layer, which is refractory mortar. The winding height of induction coil 10 is 300-500mm. Induction heating is performed through induction coil 10 to melt or raise the temperature of scrap steel or molten iron at the bottom of the furnace, and also to provide a heat source for the subsequent iron concentrate reduction process.
[0038] The magnetic yoke is evenly and symmetrically distributed around the induction coil 10. The yoke shielding reduces magnetic leakage, prevents furnace overheating, and improves efficiency. Simultaneously, the yoke supports and fixes the induction coil 10, resulting in a furnace with high strength and low noise. The yoke is made of oriented silicon steel sheets, which have low heat generation, good magnetic field shielding, and a waterless cooling design, preventing water seepage and sparking later. The size and distribution of the yoke effectively shield the magnetic field while also providing space for the injection channel.
[0039] The furnace body 7 has a bottom blowing hole 15 at the bottom, and the bottom blowing hole 15 is connected to the hydrogen injection device through the bottom blowing hydrogen pipe 14.
[0040] The bottom blowhole of the furnace lining 12 is tamped with ventilated sand and 16 is buried with ventilated bricks, which allows for bottom blowing of hydrogen.
[0041] The medium-frequency furnace is equipped with a tilting device 18, which uses hydraulic tilting. The tilting is smooth, safe and stable. Molten iron in the furnace can be poured out and cast into ingots through the tilting device 18.
[0042] This utility model's medium-frequency furnace achieves the reduction smelting of iron concentrate / iron ore by injecting hydrogen into the furnace. Hydrogen can be injected evenly from the sides of the furnace body 7 via blowholes, or from the bottom of the furnace body 7 via bottom blowing. Powdered materials can enter the furnace body 7 vertically through the feeding channel on the dust hood 1 to participate in the reaction. Materials can be added at any time during production to adjust the material ratio, ensuring precise reduction and slagging reaction.
[0043] The foregoing description only illustrates certain exemplary embodiments of the present invention. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.
Claims
1. A medium-frequency furnace for reducing iron concentrate with hydrogen, comprising: Furnace body (7), dust collection hood (1) installed on top of the furnace body (7); as well as The base (17) disposed at the bottom of the furnace body (7) is characterized in that: The dust collection hood (1) is provided with a vertically downward extending material feeding channel. The bottom of the material feeding channel has a material feeding port (4). The bottom of the furnace body (7) is provided with a bottom blowing hole (15). The furnace body (7) is evenly provided with multiple side blowing holes (9) around its circumference. The blowing angle of the side blowing hole (9) extends downward at an angle of 30-50° with the horizontal plane.
2. The medium-frequency furnace for reducing iron concentrate with hydrogen according to claim 1, characterized in that: The diameter of the side blowing hole (9) is 30-50mm, and the distance between the side blowing hole (9) and the furnace bottom is 300-500mm.
3. A medium-frequency furnace for reducing iron concentrate with hydrogen according to claim 1 or 2, characterized in that: The furnace body (7) has a furnace lining (12) inside. An insulating layer (11) is fixed to the outer wall of the furnace lining (12). An inductor is provided on the outer layer of the insulating layer (11). A cooling copper pipe is provided on the upper part of the inductor.
4. The medium-frequency furnace for reducing iron concentrate with hydrogen according to claim 3, characterized in that: The inner diameter of the furnace lining (12) is 100-300mm and the height is 600-1000mm. The height of the molten metal (13) in the molten pool of the furnace lining (12) is 300-500mm.
5. The medium-frequency furnace for reducing iron concentrate with hydrogen according to claim 3, characterized in that: The sensor is formed by winding an induction coil (10), and the outer surface of the induction coil (10) is provided with an insulating protective layer.
6. The medium-frequency furnace for reducing iron concentrate with hydrogen according to claim 5, characterized in that: The winding height of the induction coil (10) is 300-500mm.
7. The medium-frequency furnace for reducing iron concentrate with hydrogen according to claim 6, characterized in that: The induction coil (10) is a copper tube.
8. The medium-frequency furnace for reducing iron concentrate with hydrogen according to claim 3, characterized in that: The bottom of the molten pool of the furnace lining (12) is provided with permeable sand and permeable bricks (16).
9. The medium-frequency furnace for reducing iron concentrate with hydrogen according to claim 1, characterized in that: The dust hood (1) is connected to a rotating arm (2), and the rotating arm (2) has a channel inside that communicates with the inside of the furnace body (7). A smoke extractor (19) is installed at the end of the rotating arm (2).
10. A medium-frequency furnace for reducing iron concentrate with hydrogen according to claim 1, characterized in that: It also includes a tilting device (18), which is connected to one side of the furnace body (7), and an iron tapping port (5) is provided on the upper part of the furnace body (7).