Hermetic industrial silicon submerged arc furnace
Through a closed design and advanced furnace tamping, preheating, and refining devices, the problems of heat loss and flue gas treatment in semi-closed furnaces have been solved, realizing a highly efficient, low-consumption, and zero-carbon emission industrial silicon submerged arc furnace.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SHANXI SANYUAN CARBON CO LTD
- Filing Date
- 2024-12-12
- Publication Date
- 2026-05-21
AI Technical Summary
Existing industrial silicon submerged arc furnaces are semi-enclosed, which allows cold air to penetrate into the furnace, resulting in increased heat loss and difficulty in flue gas treatment, as well as high energy consumption, low yield, and high carbon emissions.
The furnace adopts a closed design, using a water-cooled sealed hood with a water seal structure to seal the furnace body. Combined with two-dimensional and three-dimensional spatial motion furnace tamping devices, it can achieve all-round furnace tamping operation without dead angles. The furnace body is equipped with a furnace charge preheating device and an oxygen blowing refining device to improve heat utilization efficiency.
It achieves high efficiency, low consumption, ultra-low emissions, and zero carbon emissions, improves raw material yield, reduces smelting energy consumption, reduces emissions, and increases output added value.
Smart Images
Figure CN2024138726_21052026_PF_FP_ABST
Abstract
Description
A closed industrial silicon submerged arc furnace Technical Field
[0001] This invention belongs to the field of industrial silicon submerged arc furnace smelting, specifically a closed industrial silicon submerged arc furnace. Background Technology
[0002] Submerged arc furnaces primarily utilize redox reactions to extract useful elements from ores or oxides. A large current is fed into the furnace through electrodes, creating an electric arc and resistance heat between the electrodes and the furnace charge, leading to a physicochemical reaction that yields the product. Currently, industrial silicon submerged arc furnaces are all semi-closed types. During furnace operation, the furnace door needs to be opened, allowing a large amount of cold air to enter, resulting in heat loss and increasing the difficulty of flue gas treatment. Existing submerged arc furnace smelting processes involve in-furnace roughing, out-of-furnace refining, ingot casting, crushing, grinding, packaging, and shipping, resulting in high energy consumption, low yield, and high carbon emissions.
[0003] To address these issues, those skilled in the art have proposed a closed-type industrial silicon submerged arc furnace. Summary of the Invention
[0004] To address the aforementioned technical problems, this invention provides a closed industrial silicon submerged arc furnace to solve the problems existing in the prior art.
[0005] A closed industrial silicon submerged arc furnace includes a furnace body, a support platform is provided above the furnace body, a material distribution device, a flue gas emission system, an electrode running system, a power supply system and a two-dimensional space motion furnace tamping device are provided above the support platform, and a water-cooled closed fume hood is fixed below the support platform.
[0006] The furnace body is equipped with a steel shell on the outside, and an asbestos board is installed inside the steel shell. The asbestos board serves as a flexible heat insulation layer, and the inner side of the asbestos board is a refractory brick lining. The upper part of the steel shell at the bottom of the furnace is a refractory brick layer, and the upper layer of the refractory brick is a high-temperature resistant carbon material layer. A rotating device is installed at the bottom of the furnace body, and six supporting columns are installed around the furnace body. The supporting columns are connected by a diagonal bracing structure. The top of all the supporting columns is connected to a supporting platform. A water-cooled sealed fume hood is suspended below the supporting platform. The water-cooled sealed fume hood is sealed to the upper part of the furnace body by a water seal structure.
[0007] The furnace body is also equipped with an electrode operating system and a micro-positive pressure balancing device.
[0008] Preferably, the outer ring side of the water-cooled sealed fume hood is provided with 9 inspection and explosion-proof holes and 1 nitrogen inlet hole. The side of the water-cooled sealed fume hood is provided with 3 evenly distributed visual systems along the circumferential direction. The camera of the visual system is inserted into the electric arc furnace body, and the visual screen is set in the control room of the electric arc furnace.
[0009] Preferably, the upper part of the water-cooled sealed fume hood is equipped with 9 to 27 two-dimensional spatial motion tamping devices; the side part is equipped with 3 to 15 three-dimensional spatial motion tamping devices.
[0010] Preferably, the two-dimensional spatial motion furnace tamping device includes a tamping claw, a tamping arm, a water-cooled connecting rod, a sealing sleeve, and a driving component. The tamping claw is fixed to the bottom end of the tamping arm, which is connected to the water-cooled connecting rod. The water-cooled connecting rod is connected to the driving component. A spiral guide groove, a sealing sleeve, and a guide slider are fixed on the water-cooled connecting rod, which synthesize the two-dimensional motion of the tamping claw when the driving component moves up and down. A water seal groove is provided inside the sealing sleeve, and the water-cooled connecting rod structure has a water seal float to achieve sealed isolation between the inside and outside of the furnace.
[0011] Preferably, the side of the furnace body where the silicon water exits is equipped with an oxygen blowing refining device and a continuous silicon granulation device;
[0012] After passing the oxygen refining process, the molten liquid is controlled by a needle valve to flow into an atomizing device. The device consists of a sealed, water-cooled outer shell with a cooling coil inside, filled with inert gas, and a discharge valve at the bottom.
[0013] Preferably, 27 feeding holes are evenly arranged on the support platform around the electrode. The top of the feeding holes is connected to a heat-insulated material distribution hopper for even material distribution. The inlet of the heat-insulated material distribution hopper is connected to the outlet of the material distribution device. The bottom of the feeding holes is connected to 27 furnace charge preheating devices surrounding the electrode. The furnace charge preheating devices are suspended on a sealed fume hood. The top of the heat-insulated material distribution hopper is connected to the feed branch pipe from the bell valve and the heat-insulated circumferential gas collecting pipe from the flue gas in the furnace.
[0014] Preferably, the power supply system consists of a furnace transformer and a low-voltage compensator, or a rectifier cabinet, or a variable frequency flexible power supply and a secondary busbar, and conductive copper tiles. The conductive copper tiles are held by a chain hoop device and locked or released by a wedge block pushed by a hydraulic cylinder. The chain hoop device is similar to a tank track that holds the copper tiles. The wedge sleeves at the joints are staggered and embedded, with wedge blocks inserted inside and locked or released by a hydraulic cylinder.
[0015] Preferably, the electrode running system includes an electrode pressing and releasing device and a copper tile clamping device located inside the cooling jacket and distributed vertically. The copper tile clamping device is formed by a tank track surrounding the copper tile, which is clamped onto the outer circle of the electrode. The male and female wedge sleeves are locked or released by a telescopic locking cylinder. The electrode pressing and releasing device is structured on the cooling jacket, and a graphite ring is installed at the bottom of the cooling jacket.
[0016] Preferably, the two-dimensional spatial motion furnace tamping device is fixed on the upper platform, and a monorail trolley is installed above the fixed track of the furnace tamping device. The trolley is equipped with a telescopic mechanism, and each furnace tamping device operates independently.
[0017] The three-dimensional space motion furnace tamping device is installed on the side of the sealed fume hood. It is driven by the interactive motion of two small oil cylinders fixed at 90 degrees offset from the sealed fume hood to achieve 360-degree swing of the sleeve. The retractable furnace tamping rod inside the sleeve is superimposed to realize the furnace tamping operation in three-dimensional space.
[0018] Preferably, the gas collecting pipe is connected to the inlet of the waste heat boiler, the outlet of the waste heat boiler is connected to the inlet of the dust collector, the outlet of the dust collector is connected to the centrifugal fan, and 10 or more water mist nozzles are arranged on the inlet pipe of the centrifugal fan. The dust is then collected and cooled without dead angles by the agitation of the fan blades. The outlet of the fan is connected to the inlet of the centrifugal dehydrator, the outlet of the centrifugal dehydrator is connected to the intake pipe of the internal combustion engine, the intake pipe is externally connected to a differential pressure transmitter, and the outlet of the centrifugal dehydrator is connected to a vacuum dehydration belt conveyor.
[0019] Through the above technical solutions
[0020] Compared with the prior art, the present invention has the following beneficial effects:
[0021] This invention utilizes a water-sealed structure to seal the submerged arc furnace body and fume hood. The fume hood is a water-cooled, sealed type. A charge preheating device is installed inside the furnace. During operation, the hot flue gas generated by the smelting reaction within the furnace is fully utilized to heat the pre-added charge to 300-400°C upon discharge, reducing energy consumption. Real-time replenishment is performed as smelting activity decreases. A vertical two-dimensional tamping robot is installed on the furnace top, and a three-dimensional spatial motion tamping device is installed on the side of the water-cooled fume hood, enabling omnidirectional tamping operations without blind spots. This eliminates the need to open the furnace door for tamping operations, thereby preventing a large amount of cold air from entering the furnace. Attached Figure Description
[0022] Figure 1 is a schematic diagram of the structure of a closed industrial silicon submerged arc furnace according to the present invention.
[0023] Figure 2 is a top view of a closed industrial silicon submerged arc furnace as shown in Figure 1.
[0024] Figure 3 is a schematic diagram of the furnace charge preheating device shown in Figure 1;
[0025] Figure 4 is a schematic diagram of the planar structure of the electrode operating system shown in Figure 1;
[0026] Figure 5 is a three-dimensional structural schematic diagram of the electrode operating system shown in Figure 1;
[0027] Figure 6 is a schematic diagram of the structure of the two-dimensional spatial motion tamping furnace device of the present invention;
[0028] Figure 7 is a structural schematic diagram of the three-dimensional spatial motion tamping furnace device of the present invention;
[0029] Figure 8 is a schematic diagram of the silicon granulation device of the present invention;
[0030] Figure 9 is a schematic diagram of the micro-positive pressure balancing device of the present invention.
[0031] In the picture:
[0032] 100. Furnace body; 1. Rotating device; 2. Furnace shell; 3. Asbestos board; 4. Refractory brick lining; 5. Carbon material layer; 6. Supporting column; 7. Water seal; 8. Visual system; 9. Sealed fume hood; 10. Power supply system; 11. Supporting platform; 12. Charge preheating device; 13. Flue gas emission system; 14. Material distribution device; 15. Insulated material distribution hopper; 16. Two-dimensional spatial motion tamping device; 16.1 16.1 Furnace claws; 16.2 Preheating material device; 16.3 Water-cooled connecting rod; 16.4 Sealing sleeve; 16.5 Water seal groove one; 16.6 Water seal float one; 16.7 Guide slider; 16.8 Guide groove; 16.9 Drive component; 17. Electrode running system; 17.1 Electrode pressing and releasing device; 17.2 Copper tile clamping device; 17.3 Cooling jacket; 17.4 Graphite ring; 17.5 Locking oil 17.6 Cylinder; 18. Inspection and explosion-proof hole; 19. Three-dimensional space motion tamping device; 19.1 Connecting ball; 19.2 Flange pair; 19.3 Sleeve; 19.4 Drive mechanism; 19.5 Tamping rake; 19.6 Transmission mechanism; 19.7 Sealing partition; 20. Oxygen blowing refining device; 20.1 Discharge channel; 20.1 Oxygen inlet; 21. Silicon granulation device; 21.1 Atomizer; 21.2 Water cooling device; 21.3 Collection system; 21.4 Airlock; 22. Feeding hole; 23. Discharge port; 24. Balance cabinet; 25. Water seal tank II; 26. Water seal float II; 27. Counterweight; 28. Air inlet pipe; 29. Air outlet pipe; 30. Conical valve; 31. Centrifugal fan; 32. Spraying device; 33. Centrifugal dewatering machine; 34. Vacuum dewatering belt conveyor. Detailed Implementation
[0033] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.
[0034] Example 1: As shown in Figures 1 to 9: The present invention provides a closed industrial silicon submerged arc furnace, including a furnace body 100, a support platform 11 above the furnace body 100, a material distribution device 14, a flue gas emission system 13, an electrode running system 17, a power supply system 10 and a two-dimensional space motion furnace tamping device 16 above the support platform 11, and a water-cooled closed fume hood 9 fixed below the support platform 11.
[0035] The furnace body 100 is provided with a steel shell on the outside, and an asbestos board 3 is provided inside the steel shell. The asbestos board 3 serves as a heat insulation flexible layer, and the inner side of the asbestos board 3 is a refractory brick furnace lining 4. The upper part of the steel shell at the bottom of the furnace is a refractory brick layer, and the upper layer of the refractory brick is a high-temperature resistant carbon material layer. A rotating device 1 is provided at the bottom of the furnace body 100. Six supporting columns 6 are provided around the furnace body 100. The supporting columns 6 are connected by a diagonal bracing structure. The top of all the supporting columns 6 is connected to a supporting platform 11. A water-cooled sealed fume hood 9 is suspended below the supporting platform 11. The water-cooled sealed fume hood 9 is sealed to the upper part of the furnace body 100 by a water seal structure.
[0036] The furnace body 100 is also equipped with an electrode operating system 17 and a micro positive pressure balancing device.
[0037] As shown in Figure 1, the furnace body 100 of the electric arc furnace is a steel shell welded from steel plates. An asbestos board 3 forms a flexible insulating layer inside the steel shell, and refractory brick lining 4 lies inside the asbestos board 3. The upper part of the steel shell at the bottom of the furnace is a refractory brick layer, and above the refractory bricks is a high-temperature resistant carbon material layer. A rotating device 1 is installed at the bottom of the furnace body 100, and support columns 6 are installed around the furnace body 100. The columns are connected by a diagonal bracing structure, and the tops of all columns are connected to a support platform 11. A water-cooled sealed fume hood 9 is suspended below the support platform 11, and the water-cooled sealed fume hood 9 is sealed to the upper part of the furnace body 100 using a water seal structure.
[0038] An inspection / explosion-proof hole 18 and a nitrogen inlet hole are provided on the outer ring side of the water-cooled sealed fume hood 9 for purging when needed. A series of visual systems 8 are evenly distributed along the circumference of the side of the water-cooled sealed fume hood 9. The cameras of the visual systems 8 extend into the submerged arc furnace body 100, allowing for comprehensive observation of the operating status of the three-phase electrodes inside the furnace. The visual screen is located in the submerged arc furnace control room. The entire visual system 8 is purged and cooled using nitrogen or clean coal gas, and also employs forced water cooling. Before opening the inspection / explosion-proof hole 18 or the visual system 8, the coal gas inside the submerged arc furnace must be purged with nitrogen and the oxygen content must be checked to prevent air from entering the submerged arc furnace body 100 and causing an explosion. The visual system 8 allows for remote control operation by observing the environment inside the submerged arc furnace body 100 through the cameras.
[0039] A vertical two-dimensional spatial motion tamping device 16 is evenly distributed on the upper part of the support platform 11, and a three-dimensional spatial motion tamping device 19 is evenly arranged in the circumferential direction on the side of the water-cooled sealed fume hood 9.
[0040] As shown in Figure 6, the two-dimensional spatial motion furnace tamping device 16 includes a tamping claw 16.1, a tamping arm, a water-cooled connecting rod 16.3, a sealing sleeve 16.4, and a driving component 16.9. The tamping claw 16.1 is fixed to the bottom end of the tamping arm, which is connected to the water-cooled connecting rod 16.3. The water-cooled connecting rod 16.3 is connected to the driving component 16.9. A spiral guide groove 16.8, a sealing sleeve 16.4, and a guide slider 16.7 are fixed on the water-cooled connecting rod 16.3. When the driving component 16.9 moves up and down, they combine to form the two-dimensional motion of the tamping claw 16.1. A water seal groove 16.5 is provided inside the sealing sleeve 16.4, and the water-cooled connecting rod 16.3 has a water seal float 16.6, achieving sealed isolation between the inside and outside of the furnace.
[0041] As shown in Figure 7, the three-dimensional spatial motion tamping device 19 includes a connecting sphere 19.1, a spherical flange pair 19.2, a sleeve 19.3, a drive mechanism 19.4, a tamping rake 19.5, and a transmission mechanism 19.6. One end of the connecting sphere 19.1 is connected to the sealed fume hood 9, and the other end is in contact with the spherical flange pair 19.2 fixed on the sleeve 19.3. The tamping rake 19.5 is placed inside the sleeve 19.3, with one end connected to the transmission mechanism 19.6 and the other end passing through the sealing partition 19.7. The sealed fume hood 9 extends into the submerged arc furnace body 100. The outer side of the sleeve 19.3 is connected to the drive mechanism 19.4. The drive mechanism 19.4 drives the sleeve 19.3 to swing by the combined motion of two small hydraulic cylinders with different degrees of rotation. The retractable tamping rod inside the sleeve 19.3 is superimposed to realize the tamping operation in three-dimensional space.
[0042] As shown in Figures 1 and 2, a feeding hole 22 is evenly arranged on the support platform 11 around the electrode. The top of the feeding hole 22 is connected to the heat-insulated distribution hopper 15 for even distribution of materials. The inlet of the heat-insulated distribution hopper 15 is connected to the outlet of the feeding distribution device 14. The bottom of the feeding hole 22 is connected to a furnace charge preheating device 12 surrounding the electrode. The furnace charge preheating device 12 is suspended on the sealed fume hood 9. The bottom of the furnace charge preheating device 12 extends directly to the top surface of the furnace charge to complete real-time feeding. The furnace charge preheating device 12 is always filled with furnace charge to recover the heat of the high-temperature gas generated during the reaction in the electric arc furnace to preheat the furnace charge inside. When it moves to the smelting zone, it accelerates the heating efficiency and improves the energy utilization efficiency.
[0043] As shown in Figures 4 and 5, the electrode running system 17 includes an electrode pressing and releasing device and a copper tile clamping device located inside the cooling jacket, distributed vertically. The copper tile clamping device consists of a tank track that encircles the copper tile, clamping it onto the outer circumference of the electrode. A telescopic locking cylinder is used to lock or release the mating male and female wedge sleeves. The electrode pressing and releasing device is located on the cooling jacket, with a graphite ring at the bottom. The inner side of the graphite ring is higher than the outer side and is close to the electrode. The graphite ring protects the cooling jacket from burns.
[0044] As shown in Figure 8, an oxygen blowing refining device 20 and a continuous silicon granulation device 21 are installed at the silicon molten material outlet on the side of the furnace body 100. The silicon molten material smelted from the furnace body 100 flows continuously into the oxygen blowing refining device 20 through the furnace side outlet. Oxygen is introduced from the oxygen inlet 20.1 on the side of the oxygen blowing refining device 20 for oxygen blowing refining. The silicon molten material flows quantitatively into the atomizer 21.1 in the atomizing device through the outlet channel of the oxygen blowing refining device 20. The atomizing device has various methods, such as centrifugal atomization, pressure atomization, ultrasonic atomization, gas atomization, rotary atomization, grid atomization, vortex atomization, media atomization, etc. In this embodiment, high-speed centrifugal atomization is preferred. The centrifugal atomizer 21.1 has various structures, such as disc type, cup type, rotor type, etc. In this embodiment, the preferred structure is disc type centrifugal atomizer 21.1. 1.1; The high-speed rotation of the disc-type centrifugal atomizer 21.1 atomizes the silicon water into fine particles under centrifugal force. The particle size can be adjusted according to the rotation speed and diameter of the centrifugal disc. The atomized silicon water droplets fall into the water-cooling device 21.2 in the inert gas environment for heat exchange and condensation into solid particles, which then fall into the collection system 21.3 in the inert gas environment. Finally, they are discharged through the opening and closing of the discharge device below the collection system 21.3. Further processing such as fine sieving is carried out according to market demand to meet different usage requirements. The atomization process for preparing industrial silicon powder has the advantages of high production efficiency, uniform powder particle size, high sphericity, good surface quality, environmental protection, low production cost, and high degree of automation, eliminating multiple steps in the traditional smelting process such as ingot casting, cooling, crushing, and grinding.
[0045] As shown in Figure 9, the flue gas system is connected to a micro-positive pressure balancing device, which includes a balancing cabinet 24. A water seal trough 16.5 is set at the bottom of the balancing cabinet 24. A water seal float 26 is placed in the water seal trough 16.5. A counterweight block 27 is fixed at the top of the water seal float 26. The bottom of the balancing cabinet 24 is connected to an inlet pipe 28 and an outlet pipe 29. A conical valve 30 is suspended at the top of the inner part of the water seal float 26. The conical valve 30 is located at the outlet pipe 29. The outlet pipe 29 is connected to a centrifugal fan 31. A water mist dust removal device is installed at the inlet of the centrifugal fan 31. The inlet pipe 28 is connected to the flue gas emission system 13 of the electric arc furnace body 100 through a flue gas waste heat exchanger. As the electric arc furnace operates, the gas generated inside the furnace enters the water-sealed float 26 through the flue gas emission system 13. The pressure in the water-sealed float 26 gradually increases, pushing it upward. At the same time, the cone valve 30 moves upward with the water-sealed float 26, opening the exhaust pipe and allowing the gas inside the water-sealed float 26 to be smoothly discharged to the centrifugal separator. The dust-laden water flow enters the fan, where the high-speed blades further capture dust without dead angles. The flue gas is cooled and dust-removed, and then processed by the centrifugal dewatering machine 33 to obtain clean flue gas, which is then sent to the internal combustion engine for power generation. The water obtained by centrifugal dewatering is processed by the vacuum dewatering belt conveyor 34, and the solids produced are centrally processed and recycled. When the flow rate of flue gas increases or the gas emission in the furnace decreases, the pressure of the water seal float 26 decreases, the water seal float 26 moves downward, and the cone valve 30 moves downward with the water seal float 26 to reduce the flue gas emission. The pressure of the water seal float 26 gradually returns to normal, the pressure in the furnace rises, and thus the furnace reaches a dynamic equilibrium state and maintains a slight positive pressure.
[0046] This invention relates to a closed industrial silicon submerged arc furnace, which achieves high efficiency, low energy consumption, ultra-low emissions, and zero carbon emissions. Compared with traditional submerged arc furnaces with high energy consumption and high emissions, this invention represents a revolutionary, novel, creative, and practical improvement.
[0047] The following table compares the parameters of a closed industrial silicon submerged arc furnace of the present invention with those of a traditional semi-closed submerged arc furnace:
[0048] As can be seen from the table, the 33,000 KVA closed industrial silicon submerged arc furnace of the present invention achieves ultra-low and zero carbon emissions, thereby increasing raw material yield, reducing smelting energy consumption, reducing emissions or achieving zero carbon emissions, and producing high added value.
[0049] The above is merely one embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
[0050] The embodiments of the present invention are given for the purposes of illustration and description. Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.
Claims
1. An enclosed industrial silicon smelting furnace, characterized in that include: The furnace body (100) is equipped with a water-cooled sealed fume hood (9) on its upper part.
2. The closed industrial silicon submerged arc furnace as claimed in claim 1, wherein: The water-cooled sealed fume hood (9) is characterized by having 9 to 27 two-dimensional spatial motion furnace tamping devices (16) installed on the upper part and 3 to 15 three-dimensional spatial motion furnace tamping devices (19) installed on the side.
3. The closed industrial silicon submerged arc furnace as claimed in claim 1, wherein: The furnace body (100) is connected to an oxygen blowing refining device (20) at its silicon outlet, and then to a continuous silicon granulation device (21) to finally obtain micron-sized powder material with controllable particle size.
4. The closed industrial silicon submerged arc furnace as claimed in claim 3, wherein: The top of the water-cooled sealed fume hood (9) is equipped with three or more preheating material devices (16.2) to effectively absorb and block the conductive electrode holding cylinder from heat radiation without affecting the flow of flue gas. At least three explosion-proof and inspection holes and an industrial television camera are installed on the side. The sealed fume hood (9) is fixed to the upper platform, which is supported by multiple columns.
5. The closed industrial silicon submerged arc furnace as claimed in claim 1, wherein: The upper platform is equipped with three or more insulated material distribution hoppers (15) to achieve uniform distribution of preheated material to the preheating material device (16.2), and the feed branch pipe from the bell valve and the insulated ring gas collection pipe from the flue gas in the furnace are respectively connected above.
6. The closed industrial silicon submerged arc furnace as claimed in claim 1, wherein: The gas collection pipe is connected to the inlet of the waste heat boiler, the outlet of the waste heat boiler is connected to the inlet of the dust collector, the outlet of the dust collector is connected to the centrifugal fan (31), and 10 or more water mist nozzles are arranged on the inlet pipe of the centrifugal fan (31) to further capture dust and cool it down. Then, the dust is captured and cooled down without dead angles by the agitation of the fan blades. The outlet of the fan is connected to the inlet of the centrifugal dehydrator (33), and the outlet of the centrifugal dehydrator (33) is connected to the intake pipe (28) of the internal combustion engine. The intake pipe (28) is equipped with a differential pressure transmitter to ensure that the closed electric arc furnace flue gas system is always in a slightly positive pressure and operates safely. The outlet of the centrifugal dehydrator (33) is connected to the vacuum dehydration belt conveyor (34). The solid waste after dehydration is centrally treated and the water is recycled.
7. The closed industrial silicon submerged arc furnace as claimed in claim 1, wherein: The power supply system (10) consists of a furnace transformer and a low-voltage compensator, or a rectifier cabinet, or a variable frequency flexible power supply and a secondary busbar, and conductive copper tiles. The conductive copper tiles are held by a chain hoop device and locked or released by a wedge block pushed by a hydraulic cylinder.
8. The closed industrial silicon submerged arc furnace as claimed in claim 1, wherein: The two-dimensional space motion furnace tamping device (16) is fixed on the upper platform. A monorail trolley is installed on the upper part of the fixed track of the furnace tamping device. The trolley is equipped with a telescopic mechanism and can be moved to the position where furnace tamping operation is required at any time. Alternatively, a monorail trolley may not be provided, and each furnace tamping device can operate independently. The three-dimensional space motion tamping device (19) is installed on the side of the sealed fume hood (9), and the sleeve (19.3) is driven by the interactive motion of two small oil cylinders fixed at 90 degrees offset from the sealed fume hood (9) to achieve 360-degree swing. The retractable tamping rod inside the sleeve (19.3) is superimposed to realize the tamping operation in three-dimensional space.
9. A closed industrial silicon smelting furnace as claimed in claim 3, characterized in that: The differential pressure transmitter automatically lowers the float valve when the system pressure drops, partially closing the inlet of the centrifugal fan (31), and vice versa. Simultaneously, it controls the fan motor speed via a frequency converter through a pressure sensor output signal, thus maintaining the differential pressure of the flue gas system within a certain range.
10. A closed industrial silicon smelting furnace as claimed in claim 6, characterized in that: The continuous silicon granulation device (21) is controlled by needle valve flow after oxygen blowing refining, and the molten liquid flows into the atomization device, which is closed with water-cooled shell, has cooling coil inside, is filled with inert gas inside, and is provided with discharge valve at the bottom.
11. A closed industrial silicon smelting furnace as claimed in claim 6, characterized in that: The chain hoop device is characterized in that copper tiles are surrounded by tank chain tracks, and staggered insertion is achieved by wedge-shaped sleeves at the joint, and wedge-shaped blocks are inserted and locked or loosened by oil cylinder drive.