A cleaning device for electrostatic precipitator of yellow phosphorus furnace gas

Abstract

This application provides a cleaning device for an electrostatic precipitator for yellow phosphorus furnace gas, applied to the dust collector, which includes an air inlet and an air outlet; a screw conveyor is installed below the dust collector, and cleaning nozzles are provided at the top and openings are provided at the bottom of the dust collector to allow dust inside the dust collector to fall onto the screw conveyor. By periodically spraying water to clean the dust, coal tar, and other similar sticky substances adhering to the anode plate and cathode wire, combined with the installation of the screw conveyor, dust removal efficiency is ensured.

Description

Technical Field

[0001] This application relates to the field of yellow phosphorus electric furnace gas purification and dust removal technology, and more specifically, to a cleaning device for yellow phosphorus furnace gas electrostatic precipitator. Background Technology

[0002] The dust in the furnace gas of yellow phosphorus electric furnaces comes partly from dust carried in the raw materials and from the explosion of the furnace charge when heated. Another part comes from the volatilization and chemical reactions of volatiles in the furnace charge at high temperatures, which then condense back down as the temperature decreases. The furnace gas produced by yellow phosphorus plants has a high dust content; approximately 100-200 kg of dry dust is generated for every ton of yellow phosphorus produced. During production, the high-temperature furnace gas discharged from the top of the furnace enters the 3-4 stage spray phosphorus collection and condensation tower through the gas guide pipe, where gaseous yellow phosphorus is condensed and recovered. Dust and harmful impurities in the furnace gas are absorbed and adhered by liquid droplets, and after being collected, they fall into the phosphorus receiving tank at the bottom of the tower. Among them, SiF4 hydrolyzes into fluorosilicic acid colloidal precipitate, and dust, fluorosilicic acid, tar, etc. are mixed with yellow phosphorus to form mud phosphorus. In the phosphorus receiving tank, crude yellow phosphorus and mud phosphorus are initially separated by sedimentation due to density difference. The crude yellow phosphorus is sent to the refining tank for rinsing and refining to achieve the purity of the product yellow phosphorus. The large amount of mud phosphorus separated out contains yellow phosphorus and needs to be subjected to closed phosphorus evaporation treatment to recover the residual phosphorus in the mud phosphorus.

[0003] As can be seen from the foregoing, if the dust in the yellow phosphorus furnace gas cannot be removed before condensation and phosphorus collection, a large amount of mud phosphorus will be generated during the phosphorus collection process. The subsequent treatment of mud phosphorus will increase the phosphorus stenosis process, increase energy consumption, and pose potential environmental risks.

[0004] Currently, the spray dust removal method used for yellow phosphorus furnace gas has problems such as large amounts of phosphorus sludge, low primary phosphorus recovery rate, and long refining time. Dry dust removal for yellow phosphorus furnace gas is an important issue that urgently needs to be addressed in the yellow phosphorus industry. On February 11, 2022, the National Development and Reform Commission and three other departments issued the "Implementation Guidelines for Energy Conservation and Carbon Reduction Transformation and Upgrading in Key Areas of High Energy-Consuming Industries (2022 Edition)," which pointed out that the yellow phosphorus industry should accelerate the application of dry dust removal technology for phosphorus furnace gas in the future in terms of green technology processes.

[0005] Although dry dust removal is an effective method for purifying and removing dust from yellow phosphorus furnace gas, the gas contains impurities such as CO, phosphorus, SiF4, HS, S, and fine phosphate rock powder and coke powder. These impurities enter the dry horizontal electrostatic precipitator together. In addition, the furnace gas produced by the yellow phosphorus unit has a high dust content, with approximately 100-200 kg of dry dust generated for every ton of yellow phosphorus produced. After the dry horizontal electrostatic precipitator has been running for a period of time, dust, coal tar, and other similar sticky substances will adhere to the anode plates and cathode wires, sticking to the surface. If not cleaned in time, this will affect the formation of the electrostatic field between the anode plates and cathode wires, thus greatly reducing the dust removal efficiency of the dry horizontal electrostatic precipitator. Utility Model Content

[0006] To address the aforementioned issues, this application provides a cleaning device for electrostatic precipitators used in yellow phosphorus furnace gas production, which solves the problem of low dust removal efficiency in existing dry horizontal electrostatic precipitators used in yellow phosphorus production.

[0007] This application provides a cleaning device for an electrostatic precipitator for yellow phosphorus furnace gas, which is applied to the dust collector. The dust collector includes an air inlet and an air outlet. A screw conveyor is installed below the dust collector. A cleaning nozzle is installed at the top of the dust collector and an opening is installed at the bottom to allow dust inside the dust collector to fall onto the screw conveyor.

[0008] As an optional embodiment, the inlet end of the spiral ash conveyor is arranged lower than the outlet end, and a near-end sewage pipe and a near-end sewage pipe valve are provided near the inlet end, and an ash discharge pipe and an ash discharge valve are provided near the outlet end. The ash discharge pipe is connected to the far-end sewage pipe and the far-end sewage pipe valve.

[0009] As an optional embodiment, the cleaning nozzle is supplied with water by a water spray pipe located at the tail end of the dust collector, with the inlet end of the water delivery section of the water spray pipe being higher than the outlet end.

[0010] As an optional embodiment, the cleaning nozzle is supplied with water by a water spray pipe located at the tail end of the dust collector. The water delivery section of the water spray pipe and the screw conveyor are both arranged parallel to the axis of the dust collector, and the air inlet of the dust collector is arranged lower than the air outlet.

[0011] As an optional embodiment, a water spray pipe valve is provided on the water spray pipe to control its opening degree; the water spray pipe is connected to the cleaning nozzle through a branch pipe.

[0012] As an optional embodiment, the dust collector has multiple anode plates for dust collection arranged along its length, and multiple vertical cathode wires for discharge arranged between adjacent anode plates; the opening is located below the anode plates and cathode wires.

[0013] As an optional embodiment, the cleaning nozzles are arranged in multiple groups. In the cross-sectional direction, a group of cleaning nozzles is arranged between every two anode plates, so that the spray range covers the two anode plates below and the cathode line between the two anode plates. In the length direction, a group of cleaning nozzles is arranged above each cathode line so that the spray range covers all cathode lines.

[0014] As an optional embodiment, the inner wall of the dust collector is provided with a rapping device for striking the anode plate and / or cathode wire to shake off dust.

[0015] As an optional embodiment, the air inlet and air outlet are respectively provided with an air inlet valve and an air outlet valve to control the opening degree of air inlet and air outlet.

[0016] As an optional embodiment, the water source pressure provided by the spray pipe is not less than 0.2MPa, the water source is clean water or turbid circulating water, and the water temperature is 10-80℃.

[0017] This application provides a cleaning device for an electrostatic precipitator used in yellow phosphorus furnace gas. The precipitator includes an air inlet and an air outlet. A screw conveyor is installed below the precipitator. Cleaning nozzles are located at the top of the precipitator, and an opening at the bottom allows dust to fall onto the screw conveyor. Regular water spraying cleans dust, coal tar, and other similar sticky substances adhering to the anode plate and cathode wire. Combined with the screw conveyor, dust removal efficiency is ensured. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 A schematic diagram of the overall structure of a cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas provided in this application embodiment;

[0020] Figure 2 A cross-sectional structural schematic diagram of a cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas provided in this application embodiment;

[0021] Figure 3 A partially enlarged structural diagram of position A of the cross-sectional structure of a cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas provided in this application embodiment;

[0022] Explanation of reference numerals in the attached figures:

[0023] 1-Dust collector; 2-Air inlet; 3-Air inlet valve; 4-Water spray pipe; 5-Cleaning nozzle; 6-Near-end sewage pipe; 7-Near-end sewage pipe valve; 8-Distant-end sewage pipe valve; 9-Distant-end sewage pipe; 10-Ash discharge pipe; 11-Ash discharge valve; 12-Screw conveyor; 13-Air outlet; 14-High voltage power supply; 15-Anode plate; 16-Cathode wire; 17-Air outlet valve; 18-Water spray pipe valve. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] The wet dust removal process for yellow phosphorus furnace gas, widely used in domestic production, generates a large amount of phosphorus mud. The subsequent treatment of this mud is costly, energy-intensive, and poses potential environmental risks. Therefore, dry dust removal before the furnace gas enters the condenser to collect the solid dust is a new green and low-carbon technology encouraged by the state.

[0026] After a period of operation, dust, coal tar, and other similar sticky substances will adhere to the anode plate and cathode wires of a dry horizontal electrostatic precipitator and stick to the surface. If not cleaned in time, it will affect the formation of an electrostatic field between the anode plate and the cathode wire, thereby greatly reducing the dust removal efficiency of the dry horizontal electrostatic precipitator.

[0027] The solution provided in this application involves installing a water spraying device on the top of a dry horizontal electrostatic precipitator to periodically spray water to clean the surfaces of the anode plate and cathode wire, thereby maintaining surface cleanliness and ensuring dust removal efficiency.

[0028] This application provides a cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas, applied to precipitator 1. See also... Figure 1-3 The dust collector 1 includes an air inlet 2 and an air outlet 13; characterized in that a screw conveyor 12 is provided below the dust collector 1, and a cleaning nozzle 5 is provided at the top and an opening is provided at the bottom of the dust collector 1 so that the dust inside the dust collector 1 falls onto the screw conveyor 12.

[0029] In one embodiment provided in this application, the inlet end of the spiral ash conveyor 12 is arranged lower than the outlet end, and a near-end sewage pipe 6 and a near-end sewage pipe valve 7 are provided near the inlet end, and an ash discharge pipe 10 and an ash discharge valve 11 are provided near the outlet end. The ash discharge pipe 10 is connected to a far-end sewage pipe 9 and a far-end sewage pipe valve 8.

[0030] See Figure 1The diagram illustrates the orientation of the screw conveyor 12, where the inlet end refers to the left end and the outlet end refers to the right end. Because the screw conveyor 12 has a lifting function, it can transport materials to the discharge end even when the left side is lower than the right side. During normal operation of conveying dry ash, the dry ash is discharged through the conveying pipe 10 at the end of the screw conveyor 12 furthest from the motor end; and a near-end drain pipe 6 and a near-end drain pipe valve 7 are installed near the motor end of the screw conveyor 12. This arrangement ensures that residual water in the screw conveyor 12 can be smoothly discharged through the near-end drain pipe 6 after each water spray, ensuring thorough drainage.

[0031] For example, the tilt angle of the screw conveyor 12 can be set to 10°.

[0032] Before the ash discharge valve 11 of the ash discharge pipe 10, a remote sewage discharge valve 8 and a remote sewage discharge pipe 9 are installed to discharge sewage that may enter the ash discharge pipe 10; the remote sewage discharge pipe 9 and the near-end sewage discharge pipe 6 are combined and enter the mud and phosphorus collection pipeline.

[0033] In one embodiment provided in this application, the cleaning nozzle 5 is supplied with water by a water spray pipe 4 located at the tail end of the dust collector 1, and the inlet end of the water delivery section of the water spray pipe 4 is positioned higher than the outlet end. See also Figure 1 The diagram shows the orientation of the water supply section of the water spray pipe 4, with the inlet end pointing to the right and the outlet end pointing to the left. This arrangement ensures that any residual water in the water spray pipe 4 can be drained away promptly after each spray.

[0034] For example, the inclination angle of the water delivery section of the water spray pipe 4 can be set to 10°. Here, the water delivery section refers to the branch pipe used to connect the various nozzles, and the overall trend is that it is lower on the left and higher on the right.

[0035] In one embodiment provided in this application, the cleaning nozzle 5 is supplied with water by a water spray pipe 4 located at the tail end of the dust collector 1. The water conveying section of the water spray pipe 4 and the screw conveyor 12 are both arranged parallel to the axis of the dust collector 1. The air inlet 2 of the dust collector 1 is arranged lower than the air outlet 13.

[0036] The dust collector 1 can be tilted directly, while the water conveying section of the water spray pipe 4 and the screw conveyor 12 are set parallel to the axis of the dust collector 1 and fixed. This setting method can not only meet the requirements of the left-low and right-high setting of the water conveying section of the water spray pipe 4 and the screw conveyor 12, but also facilitate the adjustment of the angle. Only the tilt angle of the dust collector 1 needs to be adjusted, so that the tilt angle of the water conveying section of the water spray pipe 4 and the screw conveyor 12 can be adjusted synchronously.

[0037] In one embodiment provided in this application, a water spray pipe valve 18 is provided on the water spray pipe 4 to control its opening degree; the water spray pipe 4 is connected to the cleaning nozzle 5 through a branch pipe.

[0038] Multiple cleaning nozzles 5 are provided, arranged in both length and cross-sectional directions. Therefore, multiple branch pipes are arranged in a network to connect each cleaning nozzle 5 in the water conveyance section.

[0039] In one embodiment provided in this application, the dust collector 1 has multiple anode plates 15 for dust collection arranged along its length, and multiple vertical cathode wires 16 for discharge arranged between adjacent anode plates 15; the opening is located below the anode plates 15 and the cathode wires 16.

[0040] The internal space of the dust collector 1 is composed of alternating cathode wires 16 and dust-collecting anode plates 15, i.e., an anode plate-cathode wire-anode plate structure, so that as much flue gas as possible flows through the dust collection channel, and as much dust as possible is trapped. The purified gas is discharged through the outlet. The top of the cathode wires 16 can be hung on the top of the dust collector 1, or a row of cathode wires 16 can be inserted or removed one row at a time by a rod passing through the top of the cathode wires 16 along the length direction.

[0041] The cathode wire is in the form of a needle-like wire, that is, discharge spikes are set on the metal pipe wall. The more discharge spikes there are, the better the corona discharge effect. For example, the dust collector 1 of this application is a dry horizontal electrostatic precipitator, powered by a high-voltage power supply 14. When gas containing dust particles passes through the high-voltage electric field formed between the cathode wire (also known as the corona electrode) connected to the high-voltage DC power supply and the grounded anode plate, the gas is ionized due to the corona discharge of the cathode. At this time, the negatively charged gas ions move towards the anode plate under the action of the electric field force. During the movement, they collide with dust particles, causing the dust particles to become negatively charged. The charged dust particles also move towards the anode under the action of the electric field force. After reaching the anode, they release the electrons they carry, and the dust particles are deposited on the anode plate, and the purified gas is discharged from the dust collector 1.

[0042] In one embodiment provided in this application, the cleaning nozzles 5 are arranged in multiple groups. In the cross-sectional direction, a group of cleaning nozzles 5 is arranged between every two anode plates 15, so that the spray range covers the two anode plates 15 below and the cathode line 16 between the two anode plates 15. In the length direction, a group of cleaning nozzles 5 is arranged above each cathode line 16 so that the spray range covers all cathode lines 16.

[0043] The cleaning nozzles 5 are arranged at the top of the internal space of the dust collector 1. A set of cleaning nozzles 5 is arranged between every two anode plates 15, and the sprayed water is sufficient to cover and clean both anode plates 15 and the large cathode wire 16 between the two anode plates. Cleaning nozzles 5 are also arranged on the top of the two outermost anode plates 15 inside the internal space of the dust collector 1 to ensure that the water can reach the outer side of these two anode plates. The cleaning nozzles 5 must maintain an appropriate distance from the anode plates 15 and the cathode wire 16 to prevent the distance from being too small, which would affect the normal operating voltage of the high-voltage power supply 14 and thus create an electrostatic field between the anode plates 15 and the cathode wire 16.

[0044] In one embodiment provided in this application, the inner wall of the dust collector 1 is provided with a rapping device for striking the anode plate 15 and / or cathode wire 16 to shake off dust.

[0045] In one embodiment provided in this application, the air inlet 2 and the air outlet 13 are respectively provided with an air inlet valve 3 and an air outlet valve 17 to control the opening degree of air inlet and air outlet.

[0046] In one embodiment provided in this application, the water source pressure provided by the spray pipe 4 is not less than 0.2 MPa, the water source is clean water or circulating water, and the water temperature is 10-80℃. Among them, the cleaning effect is better when the water temperature is greater than 35℃.

[0047] This application provides a cleaning device for an electrostatic precipitator for yellow phosphorus furnace gas, which can be cleaned regularly through the following steps:

[0048] Step (1): Close the air inlet valve 3, and then close the air outlet valve 17;

[0049] Step (2): Turn off the high-voltage power supply 14 and stop the power supply. When the dust collector 1 is being cleaned with water spray, it is strictly forbidden to work with the power on.

[0050] Step (3): Before turning off the high-voltage power supply 14 and starting water spraying, the temperature should be cooled down for a period of time. Only when the temperature inside the dust collector 1 drops to below 90℃ (or other set temperature) can the water spray pipe 4 be connected and the water spray pipe valve 18 be opened to start water spraying.

[0051] Step (4): Close the ash discharge valve 11 on the ash discharge pipe 10 to prevent sewage from entering the dry ash collection device; open the remote sewage discharge valve 8 on the remote sewage discharge pipe 9 to discharge sewage that may enter the ash discharge pipe 10; open the near-end sewage discharge valve 7 to discharge the cleaned sewage through the near-end sewage discharge pipe 6.

[0052] Step (5): Connect the water spray valve 18 on the water spray pipe 4 and spray water through the cleaning nozzle 5 for cleaning;

[0053] Step (6): After cleaning, close valve 18 on water spray pipe 4, close valve 8 on remote sewage pipe 9, and close valve 7 on near sewage pipe 6.

[0054] Step (7): Open the outlet valve 17 and the inlet valve 3 to introduce yellow phosphorus furnace gas. After the water on the anode plate 15 and cathode wire 16 has dried, check the furnace gas at the outlet 13. When the water vapor content is not greater than 5% (or other set values), the high-voltage power supply 14 can be turned on again and the dust collector 1 can enter normal operation.

[0055] During the cleaning process, keep the screw conveyor running, close the ash discharge pipe to stop collecting dry ash, and open the sewage discharge pipe to collect the cleaning wastewater.

[0056] To avoid mixing dry ash and wastewater and affecting their respective recycling, the ash discharge pipe is closed and the sewage discharge pipe is opened during cleaning.

[0057] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas, applied to a dust collector (1), the dust collector (1) comprising an air inlet (2) and an air outlet (13); characterized in that, A screw conveyor (12) is installed below the dust collector (1). A cleaning nozzle (5) is installed at the top of the dust collector (1) and an opening is installed at the bottom so that the dust in the dust collector (1) falls onto the screw conveyor (12).

2. The cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas according to claim 1, characterized in that, The screw conveyor (12) has its inlet end lower than its outlet end, and a near-end sewage pipe (6) and a near-end sewage pipe valve (7) are installed near the inlet end, and an ash discharge pipe (10) and an ash discharge valve (11) are installed near the outlet end. The ash discharge pipe (10) is connected to a far-end sewage pipe (9) and a far-end sewage pipe valve (8).

3. The cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas according to claim 1, characterized in that, The cleaning nozzle (5) is supplied with water by a water spray pipe (4) located at the tail end of the dust collector (1), and the inlet end of the water delivery section of the water spray pipe (4) is arranged higher than the outlet end.

4. The cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas according to claim 1, characterized in that, The cleaning nozzle (5) is supplied with water by the water spray pipe (4) located at the tail end of the dust collector (1). The water conveying section of the water spray pipe (4) and the screw conveyor (12) are both arranged parallel to the axis of the dust collector (1). The air inlet (2) of the dust collector (1) is arranged lower than the air outlet (13).

5. A cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas according to claim 3 or 4, characterized in that, A water spray pipe valve (18) is provided on the water spray pipe (4) to control its opening degree; The water spray pipe (4) is connected to the cleaning nozzle (5) through a branch pipe.

6. The cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas according to claim 1, characterized in that, The dust collector (1) has multiple anode plates (15) for dust collection arranged along its length, and multiple vertical cathode wires (16) for discharge arranged between adjacent anode plates (15); the opening is located below the anode plates (15) and the cathode wires (16).

7. A cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas according to claim 6, characterized in that, The cleaning nozzles (5) are arranged in multiple groups. In the cross-sectional direction, a set of cleaning nozzles (5) is arranged between every two anode plates (15) so that the spray range covers the two anode plates (15) below and the cathode line (16) between the two anode plates (15). In the length direction, a set of cleaning nozzles (5) is arranged above each cathode line (16) so that the spray range covers all cathode lines (16).

8. A cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas according to claim 6, characterized in that, The dust collector (1) is equipped with a rapping device on its inner wall for striking the anode plate (15) and / or cathode wire (16) to shake off dust.

9. A cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas according to claim 1, characterized in that, The air inlet (2) and air outlet (13) are respectively equipped with an air inlet valve (3) and an air outlet valve (17) to control the opening degree of air inlet and air outlet.

10. A cleaning device for an electrostatic precipitator of yellow phosphorus furnace gas according to claim 3 or 4, characterized in that, The water source pressure provided by the spray pipe (4) is not less than 0.2MPa, the water source is clear water or turbid circulating water, and the water temperature is 10-80℃.

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