Silicon carbide smelting tail gas treatment equipment

Abstract

The invention relates to the field of tail gas treatment, in particular to silicon carbide smelting tail gas treatment equipment which comprises a tower body, an ash hopper is arranged at the bottom of the tower body, a gas inlet is formed in the side portion of the ash hopper, an ash discharge port is formed in the bottom of the ash hopper, and a gas outlet is formed in the top of the tower body; a tubular catalysis assembly, a desulfurization reaction assembly and a filtering assembly are sequentially arranged in the tower body from top to bottom; the filtering assembly is used for filtering tail gas, the desulfurization reaction assembly is used for removing sulfides in the tail gas, and water vapor is introduced into the tubular catalysis assembly to promote CO to be converted. According to the invention, filtration, desulfurization and carbon monoxide catalysis are integrated, a tower type distribution structure is adopted, the occupied area can be effectively reduced, meanwhile, pipeline arrangement is reduced, and the gas loss is reduced.

Description

Technical Field

[0001] This invention relates to the field of exhaust gas treatment, and more particularly to an exhaust gas treatment device for silicon carbide smelting. Background Technology

[0002] The tail gas from silicon carbide smelting mainly contains pollutants such as sulfur dioxide, carbon monoxide, carbon dioxide, and soot, which must be treated before they can be discharged in compliance with standards. In traditional processes, filtration, desulfurization, and carbon monoxide catalytic reaction treatment equipment are mostly arranged separately, resulting in large footprints and significant gas losses in pipelines. Summary of the Invention

[0003] In view of the above problems, the purpose of this invention is to provide a silicon carbide smelting tail gas treatment device. The technical solution adopted by this invention is as follows:

[0004] The present invention provides a silicon carbide smelting tail gas treatment device, including a tower body, an ash hopper at the bottom of the tower body, an air inlet at the side of the ash hopper, an ash discharge port at the bottom, and an air outlet at the top of the tower body.

[0005] The tower body is equipped with a tubular catalytic module, a desulfurization reaction module, and a filtration module arranged sequentially from top to bottom. The filtration module filters the exhaust gas, the desulfurization reaction module removes sulfides from the exhaust gas, and water vapor is introduced into the tubular catalytic module to promote CO conversion.

[0006] Preferably, the tower body includes a conversion section, a desulfurization section, and a filtration section, which are connected together sequentially from top to bottom;

[0007] The tubular catalytic converter is correspondingly located in the conversion section, the desulfurization reaction assembly is correspondingly located in the desulfurization section, and the filtration assembly is correspondingly located in the filtration section.

[0008] Preferably, the filter assembly includes a first support plate, the outer edge of which is fixed to the inner wall of the tower body. The first support plate is provided with a plurality of first air passage holes, and a recessed frame is provided at the lower end of each first air passage hole. A cylindrical filter element is provided inside the frame, and an annular pressure plate is pressed against the upper end of the cylindrical filter element. The annular pressure plate is fixed to the top surface of the first support plate.

[0009] Preferably, the cylindrical filter element is provided with a backflush pipe, and the upper end of the backflush pipe is connected to an air bag arranged on the outer wall of the tower body through a jet pipe.

[0010] Preferably, the desulfurization reaction assembly includes two parallel and inclined mesh plates, the four sides of which are fixed to the inner wall of the tower body. The upper and lower mesh plates and the side wall of the tower body form a desulfurizing agent filling channel. The side wall of the tower body is provided with a feeding port and a discharging port corresponding to the upper and lower ports of the desulfurizing agent filling channel, respectively. Both the feeding port and the discharging port are provided with detachable sealing plates.

[0011] Preferably, the tubular catalytic assembly includes a second support plate, the outer edge of which is fixed to the inner wall of the tower body. The second support plate is provided with a plurality of second air passages, each of which is provided with a sunken tube. The lower end of the tube is provided with a baffle. The tube is filled with a catalyst that converts CO into H2. Each tube is provided with a steam distribution pipe, which is provided with a plurality of steam holes. The steam distribution pipe is connected to a steam pipe arranged on the outer wall of the tower body through a connecting pipe.

[0012] Preferably, a partition is provided below the second support plate, the outer edge of the partition is fixed to the inner wall of the tower body, a plurality of vent pipes are provided on the partition, a waterproof cap is provided at the upper end of the vent pipes, and a drain pipe is provided on the side wall of the tower body corresponding to the position above the partition.

[0013] Preferably, the air inlet is connected to a flue gas cooling device.

[0014] Preferably, the flue gas cooling device includes a housing, in which a flue gas heat exchange pipe is provided. The lower end of the flue gas heat exchange pipe is connected to the exhaust gas inlet located at the lower part of the housing, and the upper end of the flue gas heat exchange pipe is connected to the exhaust gas outlet located at the upper part of the housing. A spray pipe is provided at the upper part of the housing, and a drain outlet is provided at the bottom.

[0015] Preferably, the flue gas heat exchange pipes are arranged in an S-shape within the housing.

[0016] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0017] This invention integrates filtration, desulfurization, and carbon monoxide catalysis, and adopts a tower-type distributed structure, which can effectively reduce the floor space, reduce pipeline layout, and reduce gas loss. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings.

[0019] Figure 1 This is a schematic diagram of the silicon carbide smelting tail gas treatment equipment in Embodiment 1 of the present invention;

[0020] Figure 2This is a schematic diagram of the structure of the filter component in Embodiment 1 of the present invention;

[0021] Figure 3 This is a schematic diagram of the arrangement of a single cylindrical filter element in Embodiment 1 of the present invention;

[0022] Figure 4 This is a schematic diagram of the structure of the first support plate in Embodiment 1 of the present invention;

[0023] Figure 5 This is a schematic diagram of the desulfurization reaction assembly in Embodiment 1 of the present invention;

[0024] Figure 6 This is a schematic diagram of the structure of the tubular catalytic assembly in Embodiment 1 of the present invention;

[0025] Figure 7 This is a schematic diagram of the structure of the second support plate in Embodiment 1 of the present invention;

[0026] Figure 8 This is a schematic diagram of the connection between the tower body and the flue gas cooling device in Embodiment 2 of the present invention;

[0027] Figure 9 This is a schematic diagram of the flue gas cooling device in Embodiment 2 of the present invention;

[0028] Figure 10 This is a schematic diagram of the smelting furnace section in Embodiment 3 of the present invention.

[0029] Explanation of reference numerals in the attached diagram: 1. Tower body; 101. Conversion section; 102. Desulfurization section; 103. Filtration section; 2. Ash hopper; 3. Air inlet; 4. Ash outlet; 5. Air outlet; 6. Tubular catalytic converter assembly; 601. Second support plate; 602. Second air passage hole; 603. Tube; 604. Baffle; 605. Steam distribution pipe; 606. Steam hole; 607. Connecting pipe; 608. Steam pipe; 609. Baffle plate; 610. Vent pipe; 611. Waterproof cap; 612. Drain pipe; 7. Desulfurization reaction assembly; 701. Mesh plate; 702. Desulfurizing agent filling channel; 7 03. Feeding port; 704. Discharge port; 705. Sealing plate; 8. Filter assembly; 801. First support plate; 802. First air passage hole; 803. Frame; 804. Cylindrical filter element; 805. Annular pressure plate; 806. Backflush pipe; 807. Purge pipe; 808. Air manifold; 9. Flue gas cooling device; 901. Box body; 902. Flue gas heat exchange pipe; 903. Tail gas inlet; 904. Tail gas outlet; 905. Spray pipe; 906. Drainage outlet; 10. Fixed furnace wall; 11. Movable furnace wall; 1101. Wall body; 12. Gas collection hood; 1201. Hood body. Detailed Implementation

[0030] To make the technical problems, technical solutions, and beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0031] Example 1

[0032] like Figure 1 As shown, this embodiment discloses a silicon carbide smelting tail gas treatment device, including a tower body 1, an ash hopper 2 at the bottom of the tower body 1, a discharge valve at the bottom of the ash hopper 2, an air inlet 3 on the side of the ash hopper 2, an ash discharge port 4 at the bottom, and an air outlet 5 at the top of the tower body 1.

[0033] The tower body 1 is assembled from a conversion section 101, a desulfurization section 102, and a filtration section 103, which are connected sequentially from top to bottom. Inside the tower body 1, a tubular catalytic converter 6, a desulfurization reaction assembly 7, and a filtration assembly 8 are arranged sequentially from top to bottom. The filtration assembly 8 filters the exhaust gas, the desulfurization reaction assembly 7 removes sulfides from the exhaust gas, and water vapor is introduced into the tubular catalytic converter 6 to promote CO conversion. The tubular catalytic converter 6 is correspondingly located in the conversion section 101, the desulfurization reaction assembly 7 is correspondingly located in the desulfurization section 102, and the filtration assembly 8 is correspondingly located in the filtration section 103.

[0034] like Figures 2 to 4 As shown, the filter assembly 8 includes a first support plate 801. The outer edge of the first support plate 801 is fixed to the inner wall of the filter section 103 of the tower body 1. The first support plate 801 has multiple first air passages 802. A recessed frame 803 is fixed to the lower end of each first air passage 802. A cylindrical filter element 804 is disposed within the frame 803. The cylindrical filter element 804 has a closed bottom and an open top structure. An annular pressure plate 805 presses against the upper end of the cylindrical filter element 804 and is fixed to the top surface of the first support plate 801. The annular pressure plate 805 fixes the cylindrical filter element 804 within the frame 803.

[0035] The cylindrical filter element 804 is equipped with a backflush pipe 806, and the upper end of the backflush pipe 806 is connected to the air bag 808 arranged on the outer wall of the tower body 1 through a blowpipe 807.

[0036] like Figure 5As shown, the desulfurization reaction assembly 7 includes two parallel and inclined mesh plates 701. The four sides of the mesh plates 701 are fixed to the inner wall of the desulfurization section 102 of the tower body 1. The upper and lower mesh plates 701 and the side wall of the tower body 1 form a desulfurizing agent filling channel 702. The desulfurizing agent filling channel 702 is filled with desulfurizing agent. The side wall of the tower body 1 is provided with a feeding port 703 and a discharging port 704 corresponding to the upper and lower ports of the desulfurizing agent filling channel 702, respectively. Both the feeding port 703 and the discharging port 704 are provided with detachable sealing plates 705.

[0037] like Figure 6 and 7 As shown, the tubular catalytic converter 6 includes a second support plate 601. The outer edge of the second support plate 601 is fixed to the inner wall of the conversion section 101 of the tower body 1. The second support plate 601 is provided with a plurality of second air passage holes 602. Each second air passage hole 602 is provided with a sunken tube 603. The upper end of the tube 603 is provided with a flange. The flange is fixed to the top surface of the second support plate 601 by bolts. The lower end of the tube 603 is fixed with a baffle 604. The tube 603 is filled with a catalyst (such as a copper-based or iron-chromium catalyst) that converts CO into H2. Each tube 603 is provided with a steam distribution pipe 605. The steam distribution pipe 605 is provided with a plurality of steam holes 606. The steam distribution pipe 605 is connected to a steam pipe 608 arranged on the outer wall of the tower body 1 through a connecting pipe 607.

[0038] A partition 609 is provided below the second support plate 601. The outer edge of the partition 609 is fixed to the inner wall of the tower body 1. Multiple vent pipes 610 are provided on the partition 609. A waterproof cap 611 is provided at the upper end of the vent pipe 610. A drain pipe 612 is provided on the side wall of the tower body 1 at the position above the partition 609.

[0039] The working process of this invention;

[0040] The tail gas from silicon carbide smelting enters the tower body 1 through the inlet 3. First, the tail gas passes through the filter assembly 8. After being filtered by the cylindrical filter element 804, the tail gas enters the desulfurization section 102. The blow pipe 807 in the filter assembly 8 can spray high-pressure gas to back-flush and clean the cylindrical filter element 80.

[0041] After the exhaust gas enters the desulfurization section 102, it passes through the mesh on the screen plate 701 and enters the desulfurizing agent filling channel 702 to react with the desulfurizing agent. For example, the calcium-based desulfurizing agent absorbs SO2 in the flue gas and finally generates CaSO4. The desulfurized exhaust gas then enters the conversion section 101.

[0042] After the exhaust gas enters the conversion section 101 through the vent pipe 610, it reacts with the solid catalyst (such as a copper-based or iron-chromium catalyst) in the tube 603 to cause a conversion reaction between CO and water vapor (CO + H2O → CO2 + H2 (endothermic reaction)), ultimately producing carbon dioxide and hydrogen. Water droplets formed by the condensation of water vapor fall into the waterproof cap 611 and collect in the water tank above the partition 609, eventually being discharged through the drain pipe 612.

[0043] Example 2

[0044] like Figure 8 and 9 As shown, in this embodiment, a flue gas cooling device 9 is connected to the air inlet 3. The flue gas cooling device 9 includes a housing 901, in which a flue gas heat exchange pipe 902 is provided. The flue gas heat exchange pipe 902 is arranged in an S-shape in the housing 901. The lower end of the flue gas heat exchange pipe 902 is connected to the exhaust gas inlet 903 located at the lower part of the housing 901, and the upper end of the flue gas heat exchange pipe 902 is connected to the exhaust gas outlet 904 located at the upper part of the housing 901. A spray pipe 905 is provided at the upper part of the housing 901, and a drain outlet 906 is provided at the bottom.

[0045] Example 3

[0046] The silicon carbide smelting furnace uses the Atchison process. Its main body is a rectangular tank, tens of meters long, constructed of refractory bricks. Inside are graphite electrodes; when electricity is applied, heat is generated, causing the furnace charge to react. The exhaust gases generated during silicon carbide smelting are primarily collected by a gas collection hood at the top of the furnace. Currently, some existing gas collection hoods use a telescopic structure; however, due to the long size of the smelting furnace, the manufacturing cost of this type of hood is high.

[0047] like Figure 10 As shown, based on this, a new silicon carbide smelting furnace is also proposed in this embodiment, including a fixed furnace wall 10 and a movable furnace wall 11. The fixed furnace wall 10 is U-shaped and the movable furnace wall 11 is straight. The fixed furnace wall 10 and the movable furnace wall 11 are assembled to form a rectangular trough structure silicon carbide smelting furnace. A gas collecting hood 12 is arranged above the silicon carbide smelting furnace. A tail gas discharge hole 13 is provided on the gas collecting hood 12. The tail gas discharge hole 13 is connected to the flue gas cooling device 9 in Embodiment 2 through a tail gas pipe.

[0048] The movable furnace wall 11 is assembled from multiple independent wall sections 1101. Both the fixed furnace wall 10 and the movable furnace wall 11 are made of refractory materials. The gas collecting hood 12 is assembled from multiple hood sections 1201, each of which is individually rotatably connected to the fixed furnace wall 10, and each hood section 1201 is provided with a tail gas discharge hole 13.

[0049] In use, multiple independent walls 1101 are sequentially assembled at the opening of the fixed furnace wall 10. The multiple walls 1101 are assembled into a movable furnace wall 11 to enclose the fixed furnace wall 10. The two form a rectangular trough structure. After adding the raw materials required for silicon carbide smelting into the trough, each cover 1201 is flipped over and placed on the trough. When all the covers 1201 are flipped over on the trough, a complete gas collection cover 12 is formed.

[0050] The silicon carbide production cycle is 38 days per furnace, including 9 days for charging, 8 days for smelting, 6 days for cooling, 4 days for material handling, and 7 days for unloading. Only the smelting stage generates carbon monoxide, sulfur dioxide, and a small amount of dust; the other stages only generate dust. Therefore, after the silicon carbide smelting in the furnace is complete, the wall 1101 is gradually dismantled and the corresponding cover 1201 is flipped open from one end of the furnace. After the material in this section is removed, the next section of wall 1101 is dismantled and the cover 1201 is flipped open. Dust can still be collected from the remaining sections of wall 1101 and cover 1201, thus effectively collecting dust generated during the furnace cleaning and material handling stages.

[0051] It should be noted that the dust generated during the furnace cleaning and material handling process is collected by the cover 1201 and enters the exhaust gas pipe. The exhaust gas pipe is equipped with a corresponding switching valve. At this time, by controlling the valve, the flue gas can be guided to an independent dust removal device, and it is no longer necessary to go through the equipment in Example 1 or Example 2 for treatment.

[0052] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A silicon carbide smelting tail gas treatment device, characterized in that: The tower body (1) includes a hopper (2) at the bottom of the tower body (1), an air inlet (3) on the side of the hopper (2), an ash discharge port (4) at the bottom, and an air outlet (5) at the top of the tower body (1). The tower body (1) is arranged from top to bottom as a tubular catalytic assembly (6), a desulfurization reaction assembly (7) and a filter assembly (8); the filter assembly (8) filters the tail gas, the desulfurization reaction assembly (7) removes sulfides from the tail gas, and water vapor is introduced into the tubular catalytic assembly (6) to promote the conversion of CO.

2. The silicon carbide smelting tail gas treatment equipment according to claim 1, characterized in that: The tower body (1) includes a conversion section (101), a desulfurization section (102), and a filtration section (103), which are connected together from top to bottom. The tubular catalytic unit (6) is correspondingly disposed in the conversion section (101), the desulfurization reaction unit (7) is correspondingly disposed in the desulfurization section (102), and the filter unit (8) is correspondingly disposed in the filter section (103).

3. The silicon carbide smelting tail gas treatment equipment according to claim 1, characterized in that: The filter assembly (8) includes a first support plate (801), the outer edge of which is fixed to the inner wall of the tower body (1). The first support plate (801) is provided with a plurality of first air passage holes (802). Each first air passage hole (802) is provided with a recessed frame (803) at its lower end. A cylindrical filter element (804) is provided inside the frame (803). An annular pressure plate (805) is pressed against the upper end of the cylindrical filter element (804). The annular pressure plate (805) is fixed to the top surface of the first support plate (801).

4. The silicon carbide smelting tail gas treatment equipment according to claim 3, characterized in that: The cylindrical filter element (804) is provided with a backflush pipe (806), and the upper end of the backflush pipe (806) is connected to the air bag (808) arranged on the outer wall of the tower body (1) through a spray pipe (807).

5. The silicon carbide smelting tail gas treatment equipment according to claim 1, characterized in that: The desulfurization reaction assembly (7) includes two parallel and inclined mesh plates (701). The four sides of the mesh plates (701) are fixed to the inner wall of the tower body (1). The upper and lower mesh plates (701) and the side wall of the tower body (1) constitute a desulfurizing agent filling channel (702). The side wall of the tower body (1) is provided with a feeding port (703) and a discharging port (704) corresponding to the upper and lower ports of the desulfurizing agent filling channel (702). The feeding port (703) and the discharging port (704) are each provided with a detachable sealing plate (705).

6. The silicon carbide smelting tail gas treatment equipment according to claim 1, characterized in that: The tubular catalytic assembly (6) includes a second support plate (601), the outer edge of which is fixed to the inner wall of the tower body (1). The second support plate (601) is provided with a plurality of second air passage holes (602), and each second air passage hole (602) is provided with a sunken tube (603). The lower end of the tube (603) is provided with a baffle (604). The tube (603) is filled with a catalyst that converts CO into H2. Each tube (603) is provided with a steam distribution pipe (605), and the steam distribution pipe (605) is provided with a plurality of steam holes (606). The steam distribution pipe (605) is connected to a steam pipe (608) arranged on the outer wall of the tower body (1) through a connecting pipe (607).

7. The silicon carbide smelting tail gas treatment equipment according to claim 1, characterized in that: A partition (609) is provided below the second support plate (601). The outer edge of the partition (609) is fixed to the inner wall of the tower body (1). A plurality of vent pipes (610) are provided on the partition (609). A waterproof cap (611) is provided at the upper end of the vent pipe (610). A drain pipe (612) is provided on the side wall of the tower body (1) at the position above the partition (609).

8. The silicon carbide smelting tail gas treatment equipment according to claim 1, characterized in that: The air inlet (3) is connected to a flue gas cooling device (9).

9. The silicon carbide smelting tail gas treatment equipment according to claim 1, characterized in that: The flue gas cooling device (9) includes a housing (901), in which a flue gas heat exchange pipe (902) is provided. The lower end of the flue gas heat exchange pipe (902) is connected to the exhaust gas inlet (903) located at the lower part of the housing (901), and the upper end of the flue gas heat exchange pipe (902) is connected to the exhaust gas outlet (904) located at the upper part of the housing (901). A spray pipe (905) is provided at the upper part of the housing (901), and a drain outlet (906) is provided at the bottom.

10. The silicon carbide smelting tail gas treatment equipment according to claim 1, characterized in that: The flue gas heat exchange pipe (902) is arranged in an S-shape in the housing (901).

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