Electro-fused magnesium oxide stepwise controllable cooling smelting device

Abstract

This invention discloses a stepped controllable cooling smelting device for fused magnesium oxide, relating to the field of magnesium oxide smelting technology. Specifically, it includes a segmented furnace body with electrodes arranged centrally in the center of the furnace cavity, forming a stable heating zone. In this invention, when the furnace lid rotates, the pendulum expands outward under centrifugal force, pulling the sliding sleeve downward via a connecting rod, automatically opening the material discharge port of the storage cylinder to complete the quantitative feeding into the molten pool. After reducing the rotation speed, the pendulum resets under the action of a spring and stops feeding. This linkage mechanism organically combines the feeding action with the furnace body rotation, requiring no additional power or control components. It has a compact structure and sensitive response. Simultaneously, the molten pool rotates with the furnace lid, causing the internal material to continuously tumble and resulting in more uniform heating.

Description

Technical Field

[0001] This invention relates to the field of magnesium oxide smelting technology, specifically to a stepped controllable cooling smelting device for fused magnesium oxide. Background Technology

[0002] Fused magnesia is an important magnesia refractory material produced by melting high-grade magnesite in an electric arc furnace and then cooling and crystallizing it. It is widely used in high-temperature fields such as metallurgy, building materials, and chemicals. Traditional fused magnesia preparation processes typically use magnesite as raw material, which is smelted at high temperatures and then naturally cooled or water-cooled to crystallize, obtaining fused magnesia agglomerates. These agglomerates are then crushed and sorted to obtain the finished product. However, traditional fused magnesia smelting and cooling equipment still has the following shortcomings: The cooling method is outdated and makes it difficult to achieve stepped, controllable cooling. In the production of fused magnesia, the temperature of the magnesia lump is extremely high after smelting. Natural cooling or water-cooled jacket forced cooling is often used. Natural cooling has a long cycle and low efficiency. Although water cooling can accelerate the cooling, it has problems such as high water consumption and rapid cooling leading to product cracking or poor crystal transformation. For example, patent publication number CN211823858U involves a cooling and waste heat recovery system for fused magnesia lump. The magnesia lump is transported by a railcar and cooled and waste heat is recovered by air circulation in a closed cavity. However, its treatment object is the magnesia lump after the cooling stage. It does not involve the on-site step-by-step controllable cooling of the product after smelting. It is difficult to adjust the cooling intensity in stages according to the cooling requirements. The feeding and smelting processes are separated, making it difficult to achieve continuous automated feeding. Most fused magnesia smelting equipment adopts an intermittent production method. When feeding, heating needs to be paused and the furnace cover opened, which is cumbersome to operate, results in large heat loss, and makes it difficult to guarantee the amount and uniformity of feeding. Some improved solutions, such as patent publication number CN216049126U, involve a rotating feeding device for a large crystallization fused magnesia heating furnace. It achieves automated feeding through a conveying device and a rotating cylinder. However, there is no mechanical linkage between its feeding mechanism and the rotation of the furnace body. The feeding action still relies on an independent external feeding device and does not achieve automatic feeding that is linked with the smelting process. Insufficient melting uniformity leads to unstable product quality. Electrodes in fused magnesium furnaces are usually fixed, and the furnace body lacks rotational motion. This results in uneven heat distribution of the material, frequent local overheating or under-burning, and a tendency for the charge to sinter and clump. For example, Chinese patent CN202153094U relates to a novel electric arc furnace for fused magnesium oxide smelting. It uses a PLC to control the intermittent rotation of the rotating platform to alleviate charge sintering. However, its rotation is not organically linked with processes such as feeding and cooling, and the material is not sufficiently turned over during the smelting process, still resulting in uneven heating. Summary of the Invention

[0003] The purpose of this invention is to provide a stepped controllable cooling smelting apparatus for fused magnesium oxide, thereby solving the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a stepped controllable cooling smelting apparatus for fused magnesium oxide, comprising: The segmented furnace body contains electrodes, which are concentrated in the center of the furnace cavity and arranged in a ring to form a stable heating zone. A slide is provided at the inlet of a segmented furnace body, and a rotating feeding assembly is installed on the slide. The rotary feeding assembly includes a furnace cover movably connected to a slide, a worm gear sleeve fixed on the side wall of the furnace cover, a discharge pipe fixed through the central axis of the furnace cover, a molten pool installed in the discharge pipe inside the split furnace body, and the molten pool and the discharge pipe are separately set. A storage cylinder is fixed at one end of the discharge pipe outside the split furnace body, and the magnesium oxide feeding operation is completed through the storage cylinder.

[0005] Furthermore, a lifting assembly is fixed to the outer wall of the segmented furnace body. The lifting assembly is used to control the overall height of the furnace cover and, together with the height adjustment of the slide itself, completes the material separation after smelting. A control platform is fixed on the output end of the lifting assembly, and the height adjustment of the entire slide is achieved through the slide rod and drive rod set on the control platform.

[0006] Furthermore, a worm gear is movably connected to the slide and driven by a motor set on one side. The worm gear meshes with the worm wheel sleeve on the side wall of the furnace cover on one side, so as to realize the overall rotation of the furnace cover.

[0007] Furthermore, the side wall of the discharge pipe located at the top of the furnace cover is evenly provided with slots, and a sliding sleeve is fitted on the slot. A rod provided on the inner wall of the sliding sleeve passes through the slot and is fixedly installed with a blocking rod. A conical head provided at one end of the blocking rod abuts against the discharge port provided on the storage cylinder, and magnesium oxide is fed by controlling the raising and lowering of the conical head.

[0008] Furthermore, a pendulum is uniformly rotatably connected to the top of the furnace cover, and a connecting rod is rotatably connected to the side wall of the pendulum. One end of the connecting rod is movably connected to the sliding sleeve, and the centrifugal force generated by the rotation of the furnace cover acts on the pendulum. While the pendulum moves outward as a whole, it pulls down the sliding sleeve. A spring is installed on the sliding sleeve between the furnace cover and the wall.

[0009] Furthermore, the bottom of the discharge pipe is connected to the automatic feeding operation of the molten pool as the material is discharged from the storage cylinder. After the melting is completed, the overall position of the slide is adjusted, and air circulation and cooling are carried out in combination with the ventilation openings at the bottom of the segmented furnace body.

[0010] Compared with the prior art, the beneficial effects of the present invention are: This invention achieves stepped, controllable air cooling of lightly calcined magnesia through the coordination of a sliding carriage lifting mechanism and bottom ventilation openings. After smelting, the lifting assembly raises the sliding carriage and furnace cover, separating the molten pool from the bottom of the segmented furnace body. Natural air is introduced through the bottom ventilation openings to cool the molten pool and the product. By precisely controlling the lifting height of the sliding carriage, the cross-sectional area and flow rate of the cooling air can be adjusted, thereby achieving a staged, controllable cooling process. This avoids product cracking or poor crystal transformation caused by rapid cooling, ensuring the product quality of lightly calcined magnesia. At the same time, this method uses air as the cooling medium, which significantly saves water resources compared to traditional water cooling methods, reducing production energy consumption and environmental treatment costs.

[0011] This invention also innovatively designs a centrifugal force-triggered rotating feeding component to achieve automatic feeding and uniform material distribution without stopping the machine during the smelting process. When the furnace cover rotates, the pendulum expands outward under the action of centrifugal force, and pulls the sliding sleeve downward through the connecting rod, so that the blocking rod automatically opens the material discharge port of the storage cylinder to complete the quantitative feeding into the molten pool. After the rotation speed is reduced, the pendulum resets under the action of the spring and stops feeding. This linkage mechanism organically combines the feeding action with the rotational motion of the furnace body, without the need for additional power and control components. It has a compact structure and sensitive response. At the same time, the molten pool rotates with the furnace cover, so that the internal material is constantly turned over, the heating is more uniform, and the rapid escape of gases such as carbon dioxide during the light burning process is promoted, which improves the porosity and activity of the product. Maintaining rotation during the cooling stage can also enhance the contact between the product and the air, further improving the cooling uniformity. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of the electrofused magnesium oxide stepped controllable cooling smelting device of the present invention. Figure 2 This is a schematic diagram of the stepped controllable cooling smelting device for fused magnesium oxide of the present invention without the furnace cover. Figure 3 This is a schematic diagram of the segmented furnace body electrode installation structure of the present invention; Figure 4 This is a schematic diagram of the structure in which the bottom of the discharge pipe is connected to the molten pool according to the present invention; Figure 5 This is a schematic diagram of the structure for installing a plugging rod on the sliding sleeve of the present invention; Figure 6 This is a schematic diagram of the overall structure of the material storage cylinder of the present invention.

[0013] In the diagram: 1. Segmented furnace body; 2. Electrode; 3. Lifting assembly; 4. Control platform; 5. Slide; 6. Drive rod; 7. Rotary feeding assembly; 701. Furnace cover; 702. Worm gear sleeve; 703. Pendulum; 704. Connecting rod; 705. Discharge pipe; 706. Molten pool; 707. Storage cylinder; 8. Slide sleeve; 9. Spring; 10. Blocking rod; 11. Worm gear. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] Please see Figure 1-6 The present invention provides a technical solution: Example 1: The electrofused magnesium oxide stepped controllable cooling smelting device of the present invention is mainly used in the front-end process of the two-step calcination and melting method, that is, the magnesite raw material is lightly calcined at about 1000°C in the segmented furnace body 1 to obtain lightly calcined magnesium oxide. The device controls the air cooling process by lifting the slide 5, and combines it with the rotating feeding component 7 to realize automatic uniform material distribution and rotary melting in the smelting process. At the same time, the high temperature flue gas generated by smelting is used to preheat the raw material, thereby improving the overall thermal efficiency and smelting uniformity. In specific operations, such as Figure 1 As shown, the segmented furnace body 1 has a vertical structure, with electrodes 2 centrally arranged in a ring shape in the central area of ​​the furnace cavity. The electrodes 2 are used to build a stable high-temperature heating zone in the center of the furnace cavity. A lifting assembly 3 is fixedly installed on the outer wall of the segmented furnace body 1. The output end of the lifting assembly 3 is connected to a control platform 4. The control platform 4 is equipped with a slide bar and a drive bar 6, which are used to drive and guide the slide 5 to adjust its height in the vertical direction. Before smelting begins, the control platform 4 and slide 5 are first lifted by the lifting component 3 to separate the furnace cover 701 from the segmented furnace body 1. The operator loads the magnesite raw material to be lightly burned into the storage cylinder 707 and the molten pool 706, and checks the connection status between the bottom of the discharge pipe 705 and the molten pool 706. The molten pool 706 and the discharge pipe 705 are designed separately to facilitate the separation of materials after smelting. Subsequently, the furnace cover 701 is lowered by the lifting component 3 to seal it with the segmented furnace body 1, and the electrode 2 is started to heat it. The temperature inside the furnace gradually rises to about 1000℃. During the heating process, the high-temperature flue gas generated by smelting will flow upward along the discharge pipe 705 to preheat the magnesite raw material in the storage cylinder 707, thereby recovering the waste heat of the flue gas and reducing the energy consumption of subsequent light burning. During the smelting process, the worm gear 11 is driven to rotate by the motor installed on the slide 5. The worm gear 11 meshes with the worm wheel sleeve 702 on the side wall of the furnace cover 701, thereby driving the entire furnace cover 701, the discharge pipe 705 and the molten pool 706 to rotate slowly together. The rotation speed is controlled at 5-10 revolutions per minute. The rotation of the molten pool 706 makes the internal magnesite heatd more evenly, avoiding local overheating or underburning, thereby improving the uniformity of the product quality of light-burned magnesia. After smelting is completed, the stepped controllable cooling stage begins. At this time, the lifting assembly 3 controls the slide 5 to rise as a whole, which in turn raises the furnace cover 701 and the discharge pipe 705, separating the molten pool 706 from the bottom of the segmented furnace body 1. The bottom of the segmented furnace body 1 has ventilation openings, through which natural air or forced cooling air enters the furnace body to air cool the molten pool 706 and the lightly calcined magnesia product. By controlling the rising height of the slide 5, the cross-sectional area and flow rate of the cooling air can be adjusted, thereby achieving stepped controllable cooling, avoiding product cracking or poor crystal transformation caused by rapid cooling, and significantly saving water resources compared to water cooling.

[0016] Example 2: This example focuses on describing the automatic feeding principle of the rotating feeding component 7 and its linkage mechanism with the furnace rotation. This design enables feeding to be completed without stopping the furnace during rotation, which significantly improves the continuous smelting capability. like Figure 2 and Figure 5 As shown, the rotary feeding assembly 7 includes a furnace cover 701 movably connected to the slide 5. A worm gear sleeve 702 is fixed to the side wall of the furnace cover 701 for receiving the drive of the worm gear 11. A discharge pipe 705 is fixed through the central axis of the furnace cover 701. A storage cylinder 707 is connected to the top of the discharge pipe 705, and the bottom is connected to the molten pool 706. Multiple vertical slots are evenly opened on the side wall of the discharge pipe 705, and a sliding sleeve 8 that can slide up and down is fitted outside the slots. A rod is fixed to the inner wall of the sliding sleeve 8. The rod passes through the slot and enters the inside of the discharge pipe 705. A blocking rod 10 is fixedly connected to the rod. A conical head is provided at the bottom of the blocking rod 10. The conical head abuts against the discharge port at the bottom of the storage cylinder 707. Under normal conditions, the conical head blocks the discharge port and prevents the raw material from falling by relying on the elastic force of the spring 9. like Figure 5 As shown, multiple pendulums 703 are rotatably connected to the top edge of the furnace cover 701. A connecting rod 704 is rotatably connected to the side wall of each pendulum 703. The other end of the connecting rod 704 is movably connected to the sliding sleeve 8. When the furnace cover 701 rotates at high speed under the drive of the worm gear 11, the pendulum 703 is thrown outward by centrifugal force. At the same time as the pendulum 703 expands outward, the connecting rod 704 pulls the sliding sleeve 8 to overcome the elastic force of the spring 9 and slide downward. The sliding sleeve 8 moves down, causing the blocking rod 10 to move down. The conical head at its end leaves the discharge port of the storage cylinder 707, and the discharge port is opened. The magnesite raw material in the storage cylinder 707 falls into the molten pool 706 below through the discharge pipe 705 under the action of gravity, realizing automatic feeding. When the feeding is completed, the rotation speed of the furnace cover 701 is reduced, the centrifugal force is reduced, the pendulum 703 retracts inward under the action of the return force of the spring 9, the sliding sleeve 8 moves up, the conical head re-seals the discharge port, and the feeding stops. By controlling the rotation speed and rotation duration of the furnace cover 701, precise control of the amount of material added can be achieved, avoiding insufficient melting due to excessive material added at one time. The entire material adding process is completed synchronously during the furnace body rotation and melting process, without interrupting heating or opening the furnace cover, which greatly improves production efficiency. In addition, such as Figure 3 and Figure 4 As shown, since the molten pool 706 rotates together with the discharge pipe 705 and the furnace cover 701, the material in the molten pool 706 is constantly turned over under the action of centrifugal force, which not only makes the heat transfer more uniform, but also promotes the rapid escape of gases such as carbon dioxide generated during the light calcination process, and improves the porosity and activity of the light calcined magnesium oxide. During the cooling stage, keeping the molten pool 706 rotating slowly can also make the product fully contact the cooling air, accelerate the cooling and improve the cooling uniformity, and avoid the internal stress difference caused by the different local cooling rates. In summary, this invention achieves continuous, uniform, and energy-saving light calcination of magnesite through an air cooling mechanism controlled by the lifting of the slide, an automatic feeding mechanism triggered by centrifugal force, and an integrated rotary design of the furnace body and molten pool. It has the advantages of compact structure, flexible operation, high thermal efficiency, and good product uniformity, and is especially suitable for the large-scale preparation of high-quality light calcined magnesia.

[0017] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A stepped controllable cooling smelting apparatus for fused magnesium oxide, characterized in that, include: The segmented furnace body (1) is provided with electrodes (2), and the electrodes (2) are concentrated in the center of the furnace cavity and arranged in a ring to form a stable heating zone. The slide (5) is located at the inlet of the segmented furnace body (1), and a rotating feeding assembly (7) is installed on the slide (5). The rotary feeding assembly (7) includes a furnace cover (701) movably connected to a slide (5), a worm gear sleeve (702) fixed on the side wall of the furnace cover (701), a discharge pipe (705) fixed through the central axis of the furnace cover (701), a molten pool (706) installed in the split furnace body of the discharge pipe (705), and the molten pool (706) and the discharge pipe (705) are set separately. A storage cylinder (707) is fixed at one end of the discharge pipe (705) located outside the split furnace body, and the magnesium oxide feeding operation is completed through the storage cylinder (707) during the smelting process.

2. The electrofused magnesium oxide stepped controllable cooling smelting device according to claim 1, characterized in that, The segmented furnace body (1) has a lifting assembly (3) fixed on its outer wall. The lifting assembly (3) is used to control the height of the overall furnace cover (701) and, together with the height adjustment of the slide (5), completes the material separation after the melting is completed. The output end of the lifting assembly (3) has a control platform (4) fixed on it. The height adjustment of the entire slide (5) is achieved by the slide rod and drive rod (6) set on the control platform (4).

3. The electrofused magnesium oxide stepped controllable cooling smelting apparatus according to claim 2, characterized in that, A worm gear (11) is movably connected to the slide (5) and driven by a motor set on one side. The worm gear (11) meshes with the worm wheel sleeve (702) on the side wall of the furnace cover (701) on one side, so as to realize the overall rotation of the furnace cover (701).

4. The electrofused magnesium oxide stepped controllable cooling smelting device according to claim 3, characterized in that, The side wall of the discharge pipe (705) located at the top of the furnace cover (701) is evenly provided with slots, and a sliding sleeve (8) is fitted on the slot. The rods provided on the inner wall of the sliding sleeve (8) pass through the slots and are fixedly installed with a blocking rod (10). The conical head provided at one end of the blocking rod (10) abuts against the discharge port provided on the storage cylinder (707), and magnesium oxide is fed by controlling the raising and lowering of the conical head.

5. The electrofused magnesium oxide stepped controllable cooling smelting apparatus according to claim 4, characterized in that, A pendulum (703) is rotatably connected to the top of the furnace cover (701). A connecting rod (704) is rotatably connected to the side wall of the pendulum (703). One end of the connecting rod (704) is movably connected to the sliding sleeve (8). The centrifugal force generated by the rotation of the furnace cover (701) acts on the pendulum (703). While the pendulum (703) moves outward as a whole, it pulls down the sliding sleeve (8). A spring (9) is installed in the sliding sleeve (8) between the furnace cover (701).

6. The stepped controllable cooling smelting apparatus for fused magnesium oxide according to claim 5, characterized in that, The bottom of the discharge pipe (705) is connected and automatically feeds the molten pool (706) along with the material discharge from the storage cylinder (707). After the smelting is completed, the overall position of the slide (5) is adjusted, and air circulation and cooling are carried out in combination with the ventilation opening at the bottom of the segmented furnace body (1).

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