Intermittent smoke exhaust device for self-discharging tank of submerged arc furnace and control method

Abstract

The invention discloses a submerged arc furnace self-discharging tank intermittent smoke exhaust device and a control method. The submerged arc furnace self-discharging tank intermittent smoke exhaust device comprises a hoisting self-discharging tank and a discharging box which is used for being in aligned sealing communication with the hoisted hoisting self-discharging tank and automatically discharging materials into a submerged arc furnace. The unloading box is communicated with a hoisting self-unloading tank for aligning, communicating and unloading, and a dust remover for intermittently controlling smoke discharge and dust removal is arranged in the unloading box; a hoisting self-discharging tank adopts a combined double-layer sealing design of an elastic rubber sealing disc and a trapezoidal rotating charging bell: during charging, the fan-shaped elastic rubber sealing disc is automatically attached to the inner wall of a charging hopper under the pressure of materials, so that an annular flexible sealing surface is formed, and charging raised dust is prevented from overflowing; after loading, the trapezoidal rotating bell axially moves to a low position, rigid secondary sealing is formed at the lower end of the conical loading hopper, the whole-flow sealing in the lifting and unloading process is realized by combining an elastic sealing sleeve of an aligned material opening of the unloading box, and compared with a traditional side suction hood dust collection mode, the dust leakage amount is effectively reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of smoke exhaust and dust removal, and in particular relates to an intermittent smoke exhaust device for a self-unloading tank of an electric arc furnace and a control method thereof. Background Art

[0002] In the RKEF ferronickel smelting process, charging the submerged arc furnace top is a critical step in the entire smelting process. This process utilizes a rotary kiln and hot charge tank for charging. After roasting and pre-reduction in the rotary kiln, the high-temperature calcined sand is transferred to the hot charge tank. From there, it is hoisted to the furnace top charging platform by an overhead crane on the smelter's roof. During this process, the mixed material is unloaded from the tank into the furnace top silo, from which it is fed into the submerged arc furnace through a discharge pipe below the hot charge tank for smelting.

[0003] However, the existing furnace top charging and dust removal systems present significant challenges, severely impacting energy conservation, environmental protection, and worker health. Because the hoppers require overhead cranes for lifting, dust hoods cannot be installed above them. Instead, side suction hoods are installed at the hopper inlet, resulting in poor dust collection. Furthermore, because high-temperature roasted sand is small and dry, the charging process generates significant amounts of dust, creating a harsh environment on the furnace top charging platform, with widespread smoke and dust, making it difficult to meet environmental standards. Summary of the Invention

[0004] The object of the present invention is to provide an intermittent smoke exhaust device and a control method for a self-unloading tank of an electric arc furnace, so as to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an intermittent smoke exhaust device for a self-unloading tank of an ore-heating furnace, comprising a hoisting self-unloading tank, and a discharge box for automatically unloading into the ore-heating furnace by being aligned and sealed with the hoisting self-unloading tank being hoisted, the discharge box is connected to the hoisting self-unloading tank for alignment and discharge, and a dust collector for intermittently controlling smoke exhaust and dust removal in the discharge box, the upper end of the hoisting self-unloading tank is provided with a conical charging hopper for sealing during and after charging, and the bottom end of the hoisting self-unloading tank is provided with an aligned discharge pipe for aligned and sealed discharge with the feed port at the end of the discharge box, and the aligned discharge pipe is provided with a discharge block on the port in the box body through vertical sliding of a vertical rod;

[0006] The upper end of the discharge box is provided with a positioning discharge mechanism for hoisting the self-discharging tank and utilizing the positioning discharge pipe to connect and discharge the material in a positioning and sealed manner. The upper end of the internal part of the discharge box is provided with a discharge push rod for entering the positioning discharge pipe after the positioning and sealing to lift the discharge block and automatically discharge the material.

[0007] The upper end of the dust collector is provided with a dust removal speed-regulating fan which is connected to the discharge box and automatically adjusts the air volume to meet the dust removal needs according to the actual feeding situation. One side of the dust removal speed-regulating fan is connected to the side of the dust collector with a built-in pulse filter bag for intermittent smoke exhaust and dust removal treatment of the dust generated during unloading.

[0008] Preferably, an air inlet is provided at the upper left side of the dust collector and is connected to the output end of the dust removal speed regulation fan through a pipe. An active fan is provided at the corresponding upper end of the air inlet to quickly evaporate the water vapor in the dust in the dust collector and discharge it to the outside by the active fan, and the other end of the active fan is connected to one side of the dust collector.

[0009] Preferably, an air storage tank is provided on one side of the upper end of the dust collector, and the output end of the air storage tank is connected to a horizontally arranged blowing pipe extending through and into the interior of the dust collector, and the bottom surface of the blowing pipe is evenly connected to backwashing branch pipes vertically corresponding to the filter bags for backwashing.

[0010] Preferably, a dust exhaust branch pipe is provided at one end of the concave surface of the special-shaped partition provided at the bottom end of the dust collector, and a swing valve is provided at the other end of the dust exhaust branch pipe. The output end of the swing valve is connected to a dust exhaust pipe, and one end of the dust exhaust pipe extends to the outside of one side of the dust collector.

[0011] Preferably, the upper ends of the hoisting self-unloading tank are provided with lifting rods inclined on both sides for lifting by an overhead crane, and the conical loading hopper port is evenly provided with elastic rubber sealing disks with a fan-shaped structure, and the elastic rubber sealing disks are combined to form a loading and unloading dust-proof disk that is conducive to sealing during loading and unloading to prevent smoke and dust from overflowing.

[0012] Preferably, a servo motor is provided in the hoisting self-unloading tank through a strip plate, and a trapezoidal rotating bell for axial movement is connected to the rotating shaft of the servo motor. One end of the vertical rod is fixed at the center position of the lower end face of the strip plate, and the vertical rod is limited to pass through the unloading block with a conical end face so that the unloading block can move upward by utilizing the upward pushing force to unload.

[0013] Preferably, the alignment unloading mechanism includes an alignment hopper arranged at the center position of the upper end of the unloading box, and support limit blocks are evenly provided on the inner wall of the alignment hopper to limit the position of the hoisted self-unloading tank when it is hoisted and moved down to align with the unloading box for alignment, and an alignment material port is provided on the inner side of the alignment hopper at the upper end position of the unloading box, and an elastic sealing sleeve is provided on the inner side of the alignment material port to seal the surface of the prefabricated alignment material port of the alignment discharge pipe after alignment to prevent smoke and dust from overflowing.

[0014] Preferably, a support plate of a U-shaped structure is provided at the upper end of the discharge box, and the discharge push rod; the fixed bottom end is fixed to the center position of the upper end of the support plate, and one end of the discharge push rod extends through the alignment discharge port to the inside of the alignment hopper, and the upper end of the discharge push rod is a hollow inner cavity, and the inner diameter of the hollow inner cavity is larger than the diameter of the vertical rod, which is conducive to lifting and moving the discharge block for unloading;

[0015] The outside of the discharge box is provided with a PLC controller which is connected with the motor, valve body, dust removal speed regulating fan and active fan control to perform intermittent smoke exhaust and centrally process high concentration smoke in a short time.

[0016] Preferably, dust removal pipes connected by arc-shaped pipes are provided on both sides of the end of the discharge box, and one side of the dust removal pipe is connected to a dust removal main pipe with a control valve and connected to the dust inlet end of the dust removal speed regulating fan.

[0017] Preferably, a driving motor is provided at the bottom of the support plate, and a conical-structured unloading spiral blade is connected to the rotating shaft of the driving motor. The bottom end of the inner cavity of the unloading box is provided with a discharge pipe connected to the electric arc furnace for unloading and with an electric valve.

[0018] The present invention also provides a method for controlling intermittent smoke exhaust of a self-unloading tank of an electric arc furnace, which specifically comprises the following steps:

[0019] S1. Loading, Sealing, and Lifting Alignment: Material is injected into the hoisted self-unloading tank through the conical loading hopper. The fan-shaped elastic rubber sealing disc is pressed against the hopper wall by the material pressure, forming a primary seal. After loading is completed, the trapezoidal rotating bell moves down to a low position to achieve a secondary top seal. The bell is hoisted to the top of the discharge box via a crane and a boom, lowered along the support and limit blocks of the alignment hopper, and the alignment discharge pipe is inserted into the alignment port, where it mates with the elastic sealing sleeve to form a radial seal, completing the physical connection.

[0020] S2. Discharge triggering and material transfer: The PLC controller drives the discharge push rod to move upward, and its hollow inner cavity covers the vertical rod to lift the discharge block. At the same time, the servo motor lifts the trapezoidal rotating bell to release the top seal. Under the action of gravity, the material falls into the discharge box through the aligned discharge pipe, realizing the release of the material in the tank to the discharge box;

[0021] S3. Material conveying and furnace distribution: The drive motor in the discharge box starts the conical unloading spiral blade to convey the material to the discharge pipe. The electric material valve opens according to the PLC preset cycle, and the material is quantitatively and evenly conveyed to the submerged arc furnace. Stable material distribution is achieved by controlling the spiral speed and the valve opening and closing frequency.

[0022] S4. Dynamic dust collection and intelligent speed regulation: The dust-laden flue gas generated during unloading is fed into the dust removal main pipe through the dust removal pipe. The dust removal speed regulating fan automatically adjusts according to the displacement signal of the unloading mandrel or the weighing data: it runs at 100% power when the dust concentration is highest at the initial stage of unloading, and drops to 60% power during the material conveying stage, achieving a dynamic balance between efficient dust removal and energy saving.

[0023] S5. Dust filtration and water vapor treatment: Dust-laden gas enters the dust collector through the air inlet, the pulse filter bag intercepts dust ≥1μm, the active fan cooperates with the external heating device to discharge the moist air, accelerate the evaporation of water vapor on the surface of the filter bag, prevent dust agglomeration from clogging the filter holes, and maintain the filtration efficiency;

[0024] S6, Dust Cleaning and System Reset: When the pressure differential in the dust collector exceeds the threshold, the air tank backwashes the filter bags with a 60-80 kPa pulse jet, removing adhering dust within 0.1-0.2 seconds. Dislodged dust is collected by a shaped baffle and intermittently discharged into the dust exhaust pipe via a swing valve. Once unloading is complete, the discharge rod retracts, the discharge block resets, the self-unloading tank is hoisted away, and the seal is restored. The PLC then initiates the next automated cycle according to the preset period.

[0025] Compared with the prior art, the technical effects and advantages of the present invention are as follows: the intermittent smoke exhaust device and control method of the self-unloading tank of the submerged arc furnace,

[0026] The self-unloading tank is hoisted and equipped with a double-layer sealing design consisting of an elastic rubber sealing disc and a trapezoidal rotary bell. During loading, the fan-shaped elastic rubber sealing disc automatically adheres to the inner wall of the hopper under the pressure of the material, forming an annular flexible sealing surface to prevent the dust from overflowing. After loading, the trapezoidal rotary bell moves axially to a low position, forming a rigid secondary seal with the lower end of the conical hopper. Combined with the elastic sealing sleeve of the material port of the discharge box, the entire lifting and unloading process is sealed. Compared with the traditional side suction hood dust collection method, the dust leakage is effectively reduced, which completely solves the problem of smoke and dust overflow caused by the lack of a dust collection hood above the tank.

[0027] The dust collection fan, coupled with the discharge ram displacement signal via a PLC controller, dynamically adjusts air volume according to the discharge stage: It operates at high power during the initial discharge, when dust concentration is highest, to quickly collect high-concentration dust; it automatically reduces to low power during the material conveying phase. Combined with the close-range dust collection design of the curved dust collection pipe at the end of the discharge box, dust collection efficiency is effectively improved. Compared to traditional large dust hood systems, this system reduces ineffective open air intake, lowers dust collection air volume requirements and equipment operating energy consumption, and reduces both construction and operating costs by over 25%.

[0028] The dust collector's built-in pulse filter bag assembly improves dust interception efficiency. Simultaneously, an active fan, coupled with an external heating device, continuously exhausts moist air from the dust collector, accelerating the evaporation of moisture from the filter bag surface and preventing dust from clogged. When the pressure differential between the dust collector inlet and outlet exceeds a threshold, the air storage tank backwashes the filter bags with pressure pulses, rapidly cleaning the dust. This improves efficiency compared to traditional manual cleaning methods, ensuring the long-term stable operation of the dust collection system and avoiding environmental issues caused by filter bag clogging.

[0029] The PLC controller integrates the coordinated control logic of the unloading jack, servo motor, dust removal speed-adjustable fan, electric valve, and other equipment to achieve an automated cycle for the entire process of loading, lifting, alignment, unloading, and dust removal. By precisely controlling the jacking height of the unloading jack, the lifting speed of the trapezoidal rotating bell, and the speed of the unloading spiral blades, the system ensures uniform and stable material discharge, avoiding the intermittent dust generated by traditional gravity unloading due to impact. Furthermore, the system automatically starts and stops according to preset intermittent cycles, reducing operational errors caused by manual intervention and ensuring that dust concentration on the furnace top charging platform is consistently controlled within environmental standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a front view of the present invention's hoisting self-unloading tank and unloading box aligned for unloading;

[0031] Figure 2 This is the front view of the hoisting self-unloading tank of the present invention;

[0032] Figure 3 This is a top view of the hoisting self-unloading tank of the present invention;

[0033] Figure 4 A top view of the discharge box of the present invention;

[0034] Figure 5 This is a diagram showing the alignment of the self-unloading tank and the unloading box during unloading.

[0035] In the figure: 1. Hoisting self-unloading tank; 2. Discharge box; 3. Dust collector; 4. Conical loading hopper; 5. Alignment discharge pipe; 6. Discharge block; 7. Discharge push rod; 8. Dust removal speed-regulating fan; 9. Air inlet; 10. Active fan; 11. Air storage tank; 12. Blowing pipe; 13. Backwash branch pipe; 14. Dust exhaust branch pipe; 15. Swing valve; 16. Dust exhaust pipe; 17. Hanging rod; 18. Elastic rubber sealing disc; 19. Trapezoidal rotary bell; 20. Alignment hopper; 21. Support limit block; 22. Alignment material port; 23. Elastic sealing sleeve; 24. Dust removal pipe fittings; 25. Dust removal main pipe; 26. Discharge spiral blade; 27. Discharge pipe; 28. PLC controller; 29. ​​Vertical rod. DETAILED DESCRIPTION

[0036] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0037] See also Figure 1-5 The present invention provides a technical solution: an intermittent smoke exhaust device for a self-unloading tank of an electric arc furnace, comprising a hoisting self-unloading tank 1, and a discharge box 2 for automatically unloading into the electric arc furnace in a sealed manner in alignment with the hoisting self-unloading tank 1. The discharge box 2 is connected to a dust collector 3 for intermittently controlling smoke exhaust and dust removal from the hoisting self-unloading tank 1 and the discharge box 2. In actual application, to ensure the sealing between the hoisting self-unloading tank 1 and the discharge box 2, a multi-layer sealing structure is adopted at the joint between the two. In addition to the elastic sealing sleeve 23, a high-temperature resistant graphite packing sealing layer is also added to effectively prevent smoke and dust leakage during the unloading process and reduce pollution to the working environment.

[0038] The upper end of the self-unloading tank 1 is provided with a conical charging hopper 4 that is sealed during and after loading, and the lower end of the self-unloading tank 1 is provided with a discharge pipe 5 that is aligned with the feed port at the end of the discharge box 2 for sealing and unloading. The discharge pipe 5 is located on the port in the box body and is provided with a discharge block 6 that slides vertically through a vertical rod 29. The taper of the conical charging hopper 4 is precisely calculated during design to ensure that materials can be quickly and smoothly loaded into the self-unloading tank 1, and after loading is completed, a good sealing effect can be formed through the elastic rubber sealing disc 18. During the loading process, the elastic rubber sealing disc 18 has good flexibility and elasticity, and can fit tightly with the discharge port of the charging equipment to prevent dust from being blown out.

[0039] The upper end of the discharge box 2 is provided with a positioning discharge mechanism for hoisting the self-discharging tank 1 and utilizing the positioning discharge pipe 5 to seal and connect the discharge. The upper end of the interior of the discharge box 2 is provided with a discharge push rod 7 for entering the positioning discharge pipe 5 after the positioning seal to lift the discharge block 6 for automatic discharge. The surface of the support limit block 21 in the positioning discharge mechanism has been specially treated and a wear-resistant hard alloy coating has been applied to extend its service life, ensuring that the position of the hoisting self-discharging tank 1 can be stably limited during multiple lifting and alignment processes. The discharge push rod 7 is made of high-strength alloy steel, and the inner wall of its hollow inner cavity is polished to reduce the friction resistance between it and the vertical rod 29, so that the discharge push rod 7 can more smoothly lift the discharge block 6 and realize automatic discharge.

[0040] The upper end of the dust collector 3 is provided with a dust removal speed-regulating fan 8 that is connected to the discharge box 2 and automatically adjusts the air volume to meet the dust removal requirements based on the actual feeding situation. One side of the dust removal speed-regulating fan 8 is connected to the side of the dust collector 3 with a built-in pulse filter bag for intermittent smoke exhaust and dust removal of dust generated during the discharge. The dust removal speed-regulating fan 8 is equipped with a high-precision air volume sensor that can monitor the smoke concentration and air volume requirements during the discharge process in real time and feed the data back to the PLC controller 28. The PLC controller 28 accurately adjusts the speed of the dust removal speed-regulating fan 8 according to the preset program and actual monitoring data, realizing automatic control of the air volume and ensuring that the best dust removal effect can be achieved under different feeding conditions.

[0041] An air inlet 9 is provided at the upper left side of the dust collector 3 and is connected to the output end of the dust removal speed regulating fan 8 through a pipeline. An active fan 10 is provided at the upper end of the air inlet 9 to quickly evaporate the water vapor in the dust in the dust collector 3 and discharge it to the outside by the active fan 10. The other end of the active fan 10 is connected to one side of the dust collector 3. In order to improve the evaporation and discharge efficiency of the active fan 10 on water vapor, a heating device is provided inside the dust collector 3. When the active fan 10 is working, the heating device is started synchronously to heat the air in the dust collector 3, accelerate the evaporation of water vapor, and prevent water vapor from condensing in the dust collector 3, which affects the dust removal effect and the normal operation of the equipment.

[0042] An air tank 11 is installed at one side of the upper end of the dust collector 3. The output end of the air tank 11 is connected to a horizontally arranged blowpipe 12 extending through the interior of the dust collector 3. The bottom surface of the blowpipe 12 is evenly connected to a backwash branch pipe 13 perpendicular to the corresponding filter bags for backwashing. The air tank 11 utilizes an automatic pressure regulation system. When the pressure within the air tank 11 falls below a set value, the air supply device automatically activates to replenish air. When the pressure exceeds the set value, the pressure relief valve automatically opens to relieve pressure, ensuring that the pressure within the air tank 11 remains within an appropriate range, providing a stable air source for backwashing the filter bags.

[0043] The dust collector 3 has a concave, irregularly shaped partition at its bottom end, with a dust discharge branch pipe 14 extending through one end. A rotary valve 15 is provided at the other end of the dust discharge branch pipe 14. The output end of the rotary valve 15 is connected to a dust discharge pipe 16, one end of which extends to the outside of one side of the dust collector 3. The design of the irregularly shaped partition, optimized through fluid dynamics simulation, effectively guides dust toward the dust discharge branch pipe 14, improving dust collection efficiency. The rotary valve 15 is made of a wear-resistant ceramic material with excellent sealing and wear resistance, enabling precise control of dust discharge and preventing dust leakage during the discharge process.

[0044] The upper end of the self-unloading tank 1 is provided with inclined booms 17 for lifting by an overhead crane. The conical hopper 4 is evenly spaced with fan-shaped elastic rubber sealing discs 18. These elastic rubber sealing discs 18 form a dust-proof plate for loading and unloading, which facilitates sealing during loading and unloading to prevent smoke and dust from escaping. The connection between the boom 17 and the self-unloading tank 1 utilizes a high-strength welding process and undergoes flaw detection to ensure the connection is secure and safe. The elastic rubber sealing discs 18 are made of a special rubber that is resistant to high temperatures and wear, ensuring they maintain a good seal even in high-temperature, high-dust working environments.

[0045] The hoisting self-unloading tank 1 is equipped with a servo motor through a strip plate. The servo motor's shaft is connected to a trapezoidal rotary bell 19 that moves axially. One end of the vertical rod 29 is fixed to the center of the lower end surface of the strip plate. The vertical rod 29 is limited and penetrates the discharge block 6 with a tapered end surface, so that the discharge block 6 uses an upward force to move upward to discharge the material. The servo motor uses a high-precision encoder to accurately control the rotation angle and position of the trapezoidal rotary bell 19, achieving precise control of the material flow rate. The tapered end surface of the discharge block 6 has undergone a special surface treatment to increase friction with the material, preventing material clogging during the discharge process.

[0046] The alignment unloading mechanism includes an alignment hopper 20 arranged at the center position of the upper end of the discharge box 2, and the inner wall of the alignment hopper 20 is evenly provided with support limit blocks 21 for limiting the position of the hoisted self-unloading tank 1 when it is hoisted and moved down to align with the discharge box 2 for alignment, and the inner side of the alignment hopper 20 is provided with an alignment material port 22 at the upper end position of the discharge box 2, and the inner side of the alignment material port 22 is provided with an elastic sealing sleeve 23 for sealing the surface of the alignment material port 22 after the alignment of the alignment discharge pipe 5 to prevent smoke and dust from overflowing. The inner wall of the alignment hopper 20 has been finely processed, and the surface roughness has reached a high standard, which reduces the friction resistance between the hoisted self-unloading tank 1 and the alignment hopper 20, making the alignment process smoother. The elastic sealing sleeve 23 adopts a replaceable design. When the sealing sleeve is worn or damaged, it can be quickly and conveniently replaced, reducing the maintenance cost of the equipment.

[0047] The upper end of the interior of the discharge box 2 is provided with a support plate of a U-shaped structure, and the discharge push rod 7; the fixed bottom end is fixed to the center position of the upper end of the support plate, and one end of the discharge push rod 7 passes through the alignment discharge port 22 and extends to the interior of the alignment hopper 20. The upper end of the discharge push rod 7 is a hollow inner cavity, and the inner diameter of the hollow inner cavity is larger than the diameter of the vertical rod 29, which is conducive to lifting and moving the discharge block 6 for unloading. The support plate adopts a high-strength steel structure and is optimized by finite element analysis to ensure that it can withstand the weight of the discharge push rod 7 and the material during the unloading process and maintain the stability of the structure. A buffer device is provided at the bottom of the hollow inner cavity of the discharge push rod 7. When the discharge block 6 is lifted, the buffer device can effectively reduce the impact force and protect the discharge push rod 7 and the discharge block 6.

[0048] The discharge box 2 is equipped with a PLC controller 28, which is connected to the motor, valve, dust removal speed-adjustable fan 8, and active fan 10 for intermittent smoke exhaust, allowing for the centralized treatment of high-concentration smoke in a short period of time. The PLC controller 28 utilizes a modular design, offering excellent scalability and maintainability. By programming different control programs, the equipment can be controlled in a variety of operating modes to meet the needs of different production processes. The PLC controller 28 also has a fault diagnosis function, capable of real-time monitoring of the equipment's operating status. When a fault occurs, it can quickly and accurately locate the fault point and issue an alarm signal.

[0049] Dust removal pipes 24, connected by curved ducts, run through both ends of the discharge box 2. One side of the dust removal pipes 24 is connected to a dust removal main pipe 25 with a control valve, which communicates with the dust inlet of the dust removal speed-regulating blower 8. The dust removal pipes 24 and main pipe 25 are made of high-temperature and corrosion-resistant stainless steel, and the inner walls of the pipes are smoothed to reduce the flow resistance of the dust within the pipes. The control valve is an electrically adjustable valve, which can precisely adjust the valve opening according to the instructions of the PLC controller 28 to control the dust flow.

[0050] A drive motor is installed at the bottom of the support plate, and a conical unloading spiral blade 26 is drivingly connected to the drive motor's rotating shaft. A discharge pipe 27 with an electric valve is installed at the bottom of the discharge chamber 2, which is connected to the submerged arc furnace for unloading. The drive motor utilizes variable frequency speed regulation technology, which can adjust the speed of the unloading spiral blade 26 in real time according to the unloading speed and material characteristics, ensuring uniform and stable material delivery from the discharge chamber 2 to the submerged arc furnace. The electric valve adopts a double-disc structure, which provides excellent sealing and reliability, effectively preventing the high-temperature gas in the submerged arc furnace from flowing back into the discharge chamber 2, ensuring safe operation of the equipment.

[0051] The present invention also provides a method for controlling intermittent smoke exhaust of a self-unloading tank of an electric arc furnace, which specifically comprises the following steps:

[0052] S1. Loading and top sealing

[0053] The material is injected into the tank through the conical loading hopper 4 on the top of the hoisting self-unloading tank 1. During the loading process, the elastic rubber sealing disc 18 with a fan-shaped structure in the port automatically adheres to the inner wall of the loading hopper under the pressure of the material, forming an annular sealing surface to prevent dust from overflowing during loading; after the loading is completed, the servo motor drives the trapezoidal rotary bell 19 to move axially to the low position, forming a secondary seal with the lower end of the conical loading hopper 4, ensuring that there is no dust leakage during transportation;

[0054] S2. Lifting alignment and bottom sealing

[0055] Hook the boom 17 with the crane hook, and lift the self-unloading tank 1 filled with materials to the top of the discharge box 2, and slowly lower it into the alignment hopper 20. At this time, the alignment discharge pipe 5 is inserted into the alignment material port 22 along the support limit block 21, and the pipe end is tightly fitted with the elastic sealing sleeve 23 to form a radial seal; the elastic sealing sleeve 23 on the top of the discharge box 2 fills the gap through compression deformation, and cooperates with the discharge block 6 at the bottom of the self-unloading tank 1 for initial sealing, completing the physical docking and sealing of the discharge system;

[0056] S3, unloading push rod triggers automatic unloading

[0057] When the hoisting self-unloading tank 1 and the discharge box 2 are aligned, the discharge push rod 7 in the discharge box 2 is driven by the PLC controller 28 to extend upward, and its hollow inner cavity sheathes the vertical rod 29 and applies a top force, so that the discharge block 6 with a tapered end face overcomes gravity and moves vertically upward along the vertical rod 29, opening the discharge port at the bottom of the aligned discharge pipe 5. At the same time, the servo motor synchronously drives the trapezoidal rotary bell 19 to lift axially, and the material falls from the hoisting self-unloading tank 1 through the aligned discharge pipe 5 into the discharge box 2 under the action of gravity;

[0058] S4. Material transportation and furnace unloading

[0059] The drive motor in the discharge box 2 starts, driving the conical discharge spiral blade 26 to rotate, and the material falling into the box is transported along the bottom of the inner cavity to the discharge pipe 27. The electric valve on the discharge pipe 27 opens periodically according to the preset program of the PLC, and the material is quantitatively transported into the submerged arc furnace to achieve uniform distribution.

[0060] S5, intermittent smoke collection

[0061] The dust-laden flue gas generated during the unloading process flows into the dust removal main pipe 25 through the dust removal pipes 24 on both sides of the end of the unloading box 2. The dust removal speed-regulating fan 8 automatically adjusts its speed according to the displacement signal of the unloading push rod 7 or the data of the weighing sensor: when the dust concentration is highest in the initial unloading stage, the fan operates at 100% power; the power is reduced to 60% during the material conveying stage, achieving a dynamic match between energy saving and efficient dust removal.

[0062] S6. Dust filtration and water vapor treatment

[0063] The dust-laden gas enters the dust collector 3 through the air inlet 9, where it first passes through a pulse filter bag group for solid-gas separation. Dust particles with a particle size of ≥1μm are intercepted on the surface of the filter bags. At the same time, the active fan 10 runs continuously, discharging the moist air in the dust collector 3 through the air ducts on both sides. In conjunction with an external heating device (not shown), the water vapor on the surface of the filter bags evaporates quickly, preventing dust agglomeration from clogging the filter holes.

[0064] S7, filter bag backwash cleaning

[0065] When the PLC controller 28 detects that the pressure difference between the inlet and outlet of the dust collector 3 exceeds a set threshold value, such as 1500Pa, the backwashing process is triggered: the gas storage tank 11 releases high-pressure gas to the injection pipe 12, and the filter bag is sprayed in the reverse direction through the backwash branch pipe 13 with a pressure pulse of 60-80kPa to remove the attached dust. The single cleaning time is controlled within 0.1-0.2 seconds to ensure that the normal dust removal process is not affected;

[0066] S8. Dust collection and discharge

[0067] The dust that falls off falls to the concave surface of the special-shaped partition at the bottom of the dust collector 3 under the action of gravity, and is collected by the dust discharge branch pipe 14 to the swing valve 15. The swing valve 15 operates intermittently at a speed of 20-30 rpm, and discharges the dust into the dust discharge pipe 16 in a quantitative manner. Finally, it is transported to the dust collection bin (not shown) for subsequent processing;

[0068] S9, system reset and loop control

[0069] After unloading is completed, the unloading push rod 7 retracts to its original position, and the unloading block 6 resets the seal to the discharge pipe 5 under the action of gravity; the hoisting self-unloading tank 1 is lifted away from the unloading box 2 by the overhead crane, and the elastic rubber sealing disk 18 and the trapezoidal rotating bell 19 restore the initial sealing state. The PLC controller 28 automatically starts the next round of loading-unloading-dust removal cycle according to the preset intermittent period, such as 5 to 10 minutes, to realize full process automation control.

[0070] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An intermittent smoke exhaust device for a self-unloading tank of an ore-bearing furnace, comprising a hoisting self-unloading tank (1), and a discharge box (2) for automatically unloading the material into the ore-bearing furnace in a sealed manner in alignment with the hoisting self-unloading tank (1), the discharge box (2) being connected to a dust collector (3) for intermittently controlling smoke exhaust and dust removal in the hoisting self-unloading tank (1) and the discharge box (2), characterized in that: The upper end of the hoisting self-unloading tank (1) is provided with a conical charging hopper (4) for sealing during and after charging, and the lower end of the hoisting self-unloading tank (1) is provided with a counter-positioned discharge pipe (5) for counter-positioning and sealing discharge with the feed port at the end of the discharge box (2), and the counter-positioned discharge pipe (5) is located on the port in the box body and is provided with a discharge block (6) through a vertical rod (29) for vertical sliding; The upper end of the discharge box (2) is provided with a positioning discharge mechanism for hoisting the self-discharging tank (1) and utilizing the positioning discharge pipe (5) to connect and discharge materials in a positioning and sealed manner. The upper end of the interior of the discharge box (2) is provided with a discharge push rod (7) for entering the positioning discharge pipe (5) after the positioning and sealing, and lifting the discharge block (6) to automatically discharge materials. The upper end of the dust collector (3) is provided with a dust removal speed regulating fan (8) which is connected to the discharge box (2) and automatically adjusts the air volume to meet the dust removal demand according to the actual feeding situation. One side of the dust removal speed regulating fan (8) is connected to one side of the dust collector (3) with a built-in pulse filter bag for intermittent smoke exhaust and dust removal of dust generated during the discharge. An air inlet (9) is provided at an upper position on the left side of the dust collector (3) and is connected to the output end of the dust removal speed regulating fan (8) through a pipeline. An active fan (10) is provided at the upper end corresponding to the air inlet (9) to quickly evaporate the water vapor in the dust in the dust collector (3) and discharge it to the outside through the active fan 6, and the other end of the active fan (10) is connected to one side of the dust collector (3).

2. The intermittent smoke exhaust device for a submerged arc furnace self-unloading tank according to claim 1, characterized in that: An air storage tank (11) is provided on one side of the upper end of the dust collector (3); the output end of the air storage tank (11) is connected to a blow pipe (12) extending through and into the interior of the dust collector (3) and arranged transversely; and the bottom surface of the blow pipe (12) is evenly connected to a backwash branch pipe (13) vertically corresponding to the filter bag for backwashing.

3. The intermittent smoke exhaust device for a submerged arc furnace self-unloading tank according to claim 1, characterized in that: A dust discharge branch pipe (14) is provided through one end of the concave surface of the special-shaped partition provided at the bottom end of the interior of the dust collector (3), and a rotary valve (15) is provided at the other end of the dust discharge branch pipe (14). The output end of the rotary valve (15) is connected to a dust discharge pipe (16), and one end of the dust discharge pipe (16) extends to the outside of one side of the dust collector (3).

4. The intermittent smoke exhaust device for a submerged arc furnace self-unloading tank according to claim 1, characterized in that: The upper ends of the hoisting self-unloading tank (1) are provided with lifting rods (17) inclined on both sides thereof for lifting by a crane, and elastic rubber sealing disks (18) of fan-shaped structure are evenly provided in the port of the conical loading hopper (4), and the elastic rubber sealing disks (18) are combined to form a loading and unloading dustproof disk which is beneficial for sealing during loading and unloading to prevent smoke and dust from escaping.

5. The intermittent smoke exhaust device for a submerged arc furnace self-unloading tank according to claim 1, characterized in that: A servo motor is provided in the hoisting self-unloading tank (1) through a strip plate, and a trapezoidal rotating bell (19) for axial movement is connected to the rotating shaft of the servo motor. One end of the vertical rod (29) is fixed at the center position of the lower end surface of the strip plate, and the vertical rod (29) is limited to penetrate the unloading block (6) with a conical end surface so that the unloading block (6) moves upward to unload by utilizing an upward jacking force.

6. The intermittent smoke exhaust device for a submerged arc furnace self-unloading tank according to claim 1, characterized in that: The alignment unloading mechanism comprises an alignment hopper (20) arranged at the center position of the upper end of the unloading box (2), and support limit blocks (21) are evenly provided on the inner wall of the alignment hopper (20) for limiting the position of the hoisted self-unloading tank (1) when it is hoisted and moved downward to be aligned and connected with the unloading box (2), and an alignment material port (22) is provided on the inner side of the alignment hopper (20) at the upper end position of the unloading box (2), and an elastic sealing sleeve (23) is provided on the inner side of the alignment material port (22) for sealing the surface of the alignment material port (22) of the alignment discharge pipe (5) after prefabricating the alignment material port (22) to prevent smoke and dust from overflowing.

7. The intermittent smoke exhaust device for a submerged arc furnace self-unloading tank according to claim 6, characterized in that: The upper end of the interior of the discharge box (2) is provided with a support plate of a U-shaped structure, and the discharge push rod (7); the fixed bottom end is fixed to the center position of the upper end of the support plate, and one end of the discharge push rod (7) passes through the alignment discharge port (22) and extends to the interior of the alignment hopper (20); the upper end of the discharge push rod (7) is a hollow inner cavity, and the inner diameter of the hollow inner cavity is larger than the diameter of the vertical rod (29), which is conducive to lifting and moving the discharge block (6) for unloading; The outside of the discharge box (2) is provided with a PLC controller (28) which is connected to the motor, valve body, dust removal speed regulating fan (8), and active fan (10) for intermittent smoke exhaust and centrally processes high-concentration smoke in a short time.

8. The intermittent smoke exhaust device for a submerged arc furnace self-unloading tank according to claim 1, characterized in that: Dust removal pipes (24) connected by arc-shaped pipes are provided on both sides of the end of the discharge box (2), and one side of the dust removal pipe (24) is connected to a dust removal main pipe (25) with a control valve and connected to the dust inlet end of the dust removal speed regulating fan (8).

9. The intermittent smoke exhaust device for a submerged arc furnace self-unloading tank according to claim 7, characterized in that: A driving motor is provided at the bottom of the support plate, and a conical-structured unloading spiral blade (26) is connected to the rotating shaft of the driving motor. A discharge pipe (27) connected to the submerged arc furnace for unloading and provided with an electric valve is provided at the bottom of the inner cavity of the unloading box (2).

10. A method for controlling intermittent smoke exhaust from a self-unloading tank of a submerged arc furnace according to any one of claims 1 to 9, characterized in that: The specific steps include: S1. Loading, sealing and hoisting alignment: Material is injected into the hoisting self-unloading tank (1) through the conical loading hopper (4), and the fan-shaped elastic rubber sealing disc (18) is pressed against the hopper wall by the material to form a primary seal; after the loading is completed, the trapezoidal rotating bell (19) moves down to a low position to achieve a secondary top seal; the overhead crane is used to lift it to the top of the discharge box (2) via the boom (17), and it is lowered along the support limit block (21) of the alignment hopper (20), and the alignment discharge pipe (5) is inserted into the alignment material port (22), and is pressed against the elastic sealing sleeve (23) to form a radial seal, completing the physical docking; S2. Discharge triggering and material transfer: The PLC controller (28) drives the discharge push rod (7) to move upward, and its hollow inner cavity covers the vertical rod (29) to lift the discharge block (6). At the same time, the servo motor lifts the trapezoidal rotating bell (19) to release the top seal. Under the action of gravity, the material falls into the discharge box (2) through the aligned discharge pipe (5), realizing the release of the material in the tank to the discharge box; S3, material transportation and furnace distribution: the driving motor in the discharge box (2) starts the conical unloading spiral blade (26), transports the material to the discharge pipe (27), and the electric material valve opens according to the PLC preset cycle, quantitatively and evenly transports the material into the submerged arc furnace, and stable distribution is achieved by controlling the spiral speed and the valve opening and closing frequency; S4. Dynamic dust collection and intelligent speed regulation: The dust-laden smoke generated by unloading is collected into the dust removal main pipe (25) through the dust removal pipe (24). The dust removal speed regulating fan (8) is automatically adjusted according to the displacement signal of the unloading mandrel (7) or the weighing data: the power is fully operated when the dust concentration is the highest in the initial unloading stage, and the power is reduced to 60% during the material conveying stage, thus achieving a dynamic balance between efficient dust removal and energy saving; S5, dust filtration and water vapor treatment: dust-laden gas enters the dust collector (3) through the air inlet (9), the pulse filter bag intercepts dust ≥1μm, the active fan (10) cooperates with the external heating device to discharge the moist air, accelerate the evaporation of water vapor on the surface of the filter bag, prevent dust agglomeration from clogging the filter holes, and maintain the filtration efficiency; S6. Dust removal and system reset: When the pressure difference of the dust collector (3) exceeds the threshold, the air storage tank (11) uses pulse spraying to blow the filter bag through the backwash branch pipe (13) to remove the attached dust in a short time; the detached dust is collected by the special-shaped partition and intermittently discharged into the dust exhaust pipe (16) by the swing valve (15); after the unloading is completed, the unloading rod is retracted, the unloading block is reset, the self-unloading tank is lifted off and the seal is restored, and the PLC starts the next round of automatic cycle according to the preset period.

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