System and method for treating fumes from electrolytic cell electrode replacement

Abstract

The application discloses a kind of electrolytic cell replacement electrode flue gas treatment system and method, including being set in lower area electrolytic cell and crane being active in upper area;Electrolytic cell is provided with several blocks of electrode;Crane is provided with electrode lifting lock, wherein, electrolytic cell is provided with several electrolytic cell cover plates, and opening of exposing a block of electrode is formed by opening at least one electrolytic cell cover plate;Crane is provided with fume collecting hood for collecting flue gas in electrode replacement process;Fume collecting hood includes setting in crane induced draft fan and setting in lower part of crane mechanical arm;Mechanical arm is longitudinally arranged and bottom end is provided with organ case that can enter electrolytic cell from opening to cover electrode from the top and around of electrode;Air inlet of induced draft fan is communicated with inner chamber of organ case, and air outlet of induced draft fan is connected with flue gas treatment device;Lower area is also provided with electrode cooling room, and electrode cooling room is connected with flue gas treatment device.The application not only has good flue gas treatment effect, but also will not cause energy waste.

Description

Technical Field

[0001] This invention relates to the field of flue gas treatment technology, and specifically to a flue gas treatment system and method for replacing electrodes in an electrolytic cell. Background Technology

[0002] Currently, my country's electrolytic aluminum plants have mature technologies for controlling organized emissions, which can reliably meet national emission standards. However, there are no stable and reliable methods for controlling fugitive emissions, resulting in frequent exceedances of fluoride emissions. The main source of fugitive fluoride emissions is the large amount of fluoride-containing dust generated during electrode replacement.

[0003] Current methods for controlling the problem mainly involve installing dust covers. However, these dust covers are fixed to the overhead crane, which is far from the opening of the electrolytic cell. This results in a large amount of dust not being collected. The induced draft fan is also installed at one end of the overhead crane beam, which is also far away. Due to the resistance of the pipes, the ventilation effect is poor, and to achieve the desired ventilation effect, the fan power must be increased, leading to energy waste. Furthermore, the opening of the electrolytic cell is often too large, making it easy for some flue gas to not be collected; the replaced electrodes still generate flue gas due to residual heat, causing pollution. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a flue gas treatment system and method for replacing electrodes in an electrolytic cell, which can realize the collection of flue gas throughout the entire process of replacing electrodes in an electrolytic cell, and not only has a good flue gas treatment effect, but also does not cause energy waste.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows.

[0006] An electrolytic cell electrode replacement flue gas treatment system includes an electrolytic cell located in a lower region and an overhead crane moving above the lower region in an upper region. The electrolytic cell contains several electrodes. The overhead crane is equipped with electrode lifting locks for gripping electrodes to facilitate electrode replacement. The electrolytic cell has several electrolytic cell cover plates for sealing it; opening at least one cover plate creates an opening that exposes one electrode. The overhead crane is equipped with a smoke collection hood for collecting flue gas during electrode replacement.

[0007] The smoke collection hood includes an induced draft fan mounted on the overhead crane and a rotatable and bendable robotic arm mounted at the bottom of the overhead crane; the robotic arm is arranged longitudinally and has a bellows cover at its bottom end that can enter the electrolytic cell through an opening to cover the electrodes from the top and all sides; the air inlet of the induced draft fan is connected to the inner cavity of the bellows cover through a connected exhaust gas pipe, and the air outlet of the induced draft fan is connected to a flue gas treatment device.

[0008] The lower area is also equipped with an electrode cooling chamber for cooling the replaced electrodes, and the electrode cooling chamber is connected to the flue gas treatment device through an exhaust pipe.

[0009] Preferably, the top of the electrode is provided with an electrode rod that extends out of the electrolytic cell so that the electrode can be gripped by an electrode hanger; an electrode rod channel is provided on the side of the bellows cover opposite to the electrode rod for the electrode rod to pass through.

[0010] Preferably, the top of the bellows cover is a rigid plate and is connected to the bottom of the robotic arm. The plate is surrounded by a bellows cover body that can extend downward to surround the electrodes. An I-shaped exhaust pipe is provided on the top of the plate. The longitudinal part of the I-shaped exhaust pipe is connected to two transverse parts. The four openings of the two transverse parts are bent downward and inserted into the plate to communicate with the inner cavity of the bellows cover. The air inlet of the exhaust pipe is connected to the longitudinal part of the I-shaped exhaust pipe.

[0011] Preferably, the bellows cover is provided with steel wires arranged along the extension direction of the bellows cover, and a winch is connected to the top of the steel wires. The controlled end of the winch is connected to a bellows cover motor for driving the winch to wind up and unwind the steel wires to realize the contraction and extension of the bellows cover.

[0012] Preferably, the top of the bellows cover is provided with an observation window; the overhead crane is provided with a camera for observing the operation position through the observation window, and the output end of the camera is connected to a PLC controller; the controlled ends of the robotic arm, the blower and the bellows cover are respectively connected to the output end of the PLC controller.

[0013] Preferably, the upper area is provided with a negative pressure pipe that can extend and retract as the overhead crane moves; the air outlet of the induced draft fan is connected to the negative pressure pipe, and the end of the negative pressure pipe away from the overhead crane is fixedly connected to the flue gas treatment device.

[0014] Preferably, the electrode cooling chamber is provided with a roller shutter door, and an electrode transfer cart located on one side of the roller shutter door is provided in the lower area for transporting electrodes into the electrode cooling chamber.

[0015] A flue gas treatment method for replacing electrodes in an electrolytic cell, implemented based on a flue gas treatment system for replacing electrodes in an electrolytic cell, specifically includes the following steps:

[0016] S1: Move the overhead crane to the position where the electrode needs to be replaced, and prepare to extract the electrode;

[0017] S2: Open the induced draft fan and the corresponding electrolytic cell cover;

[0018] S3: Grasp the electrode;

[0019] S4: Remove the electrode from the electrolytic cell and simultaneously lower the bellows cover to wrap the electrode. Under the action of the induced draft fan, the smoke and dust are discharged into the flue gas treatment device through the negative pressure pipe.

[0020] S5: Close the electrolytic cell cover;

[0021] S6: Move the electrode to the electrode cooling chamber;

[0022] S7: The overhead crane picks up the new electrode, and the above steps are reversed to place the new electrode into the electrolytic cell, thus completing the electrode replacement.

[0023] Preferably, step S3 specifically involves manipulating a robotic arm to attach the retracted bellows cover to the electrode to be replaced inside the electrolytic cell, which has already had its cover opened. The operating position is adjusted through the observation window to allow the electrode rod to slide into the electrode rod channel, and the electrode lock is used to secure the electrode rod for electrode retrieval.

[0024] Preferably, step S6 specifically involves the overhead crane placing the electrode onto the motor transfer cart and sliding it into the electrode cooling chamber.

[0025] Due to the adoption of the above technical solutions, the technical progress achieved by this invention is as follows.

[0026] The present invention, through the design of the electrolytic cell cover plate, can form an opening that exposes an electrode, thereby reducing the situation where a large amount of flue gas is emitted due to an excessively large opening.

[0027] This invention features a smoke collection hood that can be directly attached to the electrode at the opening of the electrolytic cell using a robotic arm, preventing air leakage. The induced draft fan, directly mounted on the overhead crane, shortens the airflow distance, improving dust collection efficiency and significantly reducing pollutant emissions during electrode replacement, while also minimizing energy waste.

[0028] The present invention can cool the electrodes by setting up an electrode cooling chamber; by connecting the induced draft fan and the electrode cooling chamber to the flue gas treatment device, centralized treatment of flue gas can be achieved. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the preparation of the extraction electrode according to the present invention;

[0030] Figure 2 This is a schematic diagram of the electrolytic cell cover plate of the present invention.

[0031] Figure 3 This is a schematic diagram of the gripping electrode of the present invention;

[0032] Figure 4 This is a schematic diagram of the electrode removal and the bellows cover of the present invention.

[0033] Figure 5 This is a schematic diagram of the closed electrolytic cell cover plate of the present invention;

[0034] Figure 6This is a schematic diagram of moving the electrode to the electrode cooling chamber according to the present invention;

[0035] Figure 7 This is a schematic diagram of the smoke collection hood structure of the present invention.

[0036] Among them: 1. Exhaust fan, 2. Robotic arm motor, 3. Robotic arm, 4. Exhaust gas duct, 41. I-shaped exhaust gas duct, 5. Observation window, 6. Bellows cover, 61. Electrode rod channel, 7. Electrode, 71. Electrode rod, 8. Electrode lock, 9. Electrolytic cell cover, 91. Opening, 10. Overhead crane, 11. Electrode turnover cart, 12. Exhaust gas emission pipe, 13. Electrode cooling room, 14. Roller shutter door. Detailed Implementation

[0037] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0038] A flue gas treatment system for replacing electrodes in an electrolytic cell, combined with Figures 1 to 6 As shown, the device includes an electrolytic cell and a crane 10. The electrolytic cell is located in the lower region and contains several electrodes 7. An electrolytic cell cover 9 is installed on the electrolytic cell to cover it. The crane 10 is movably located in the upper region above the lower region and is equipped with an electrode lock 8 to grab the electrodes 7 for replacement.

[0039] Two electrode rods 71 ​​are provided on the top of electrode 7, and the two electrode rods 71 ​​extend from the electrolytic cell so that electrode lifting lock 8 can grasp electrode 7. Electrode lifting lock 8 is prior art and is not an improvement of this invention, and its specific structure and principle will not be described in detail.

[0040] Several electrolytic cell covers 9 are arranged adjacently and can be detachably or slidably connected to the electrolytic cell, thus facilitating the opening of the electrolytic cell. Opening one or several adjacent electrolytic cell covers 9 forms an opening 91 that exposes one electrode 7, thereby preventing the flue gas from escaping due to an excessively large opening 91. Specifically, two to three electrolytic cell covers 9 can be opened to form an opening 91 that exposes one electrode 7.

[0041] The overhead crane 10 is equipped with a smoke collection hood, which is used to collect flue gas during the replacement of electrode 7.

[0042] like Figure 7 As shown, the smoke hood includes an induced draft fan 1, a robotic arm 3, and a bellows cover 6. The induced draft fan 1 is located on the upper surface of the overhead crane 10; the robotic arm 3 is located at the lower part of the overhead crane 10; and the bellows cover 6 is located at the bottom end of the robotic arm 3.

[0043] The robotic arm 3 is arranged longitudinally and is a rotatable and bendable robotic arm. This type of robotic arm is existing technology and is controlled by the robotic arm motor 2 on it, or it can be controlled by a hydraulic cylinder. The specific structure and principle will not be described in detail.

[0044] The bellows cover 6 can enter the electrolytic cell through the opening 91 to cover the electrode 7 from the top and sides, thereby preventing air leakage and the spread of flue gas during the handling and transportation of the electrode 7. The bellows cover 6 includes a plate and a bellows cover body. The plate is made of rigid material and is connected to the bottom end of the robotic arm 3. The bellows cover body is arranged around the lower part of the plate and can extend downward to surround the electrode 7.

[0045] The bellows cover 6 is equipped with a steel wire, a winch, and a bellows cover motor. The steel wire is arranged along the extension direction of the bellows cover body, and the winch and bellows cover motor are mounted on the plate at the top of the bellows cover 6. The top of the steel wire is connected to the winch, and the controlled end of the winch is connected to the bellows cover motor. The bellows cover motor drives the winch to rotate and retract the steel wire to achieve the contraction and extension of the bellows cover body.

[0046] An electrode rod channel 61 is provided on the side of the bellows cover 6 opposite to the electrode rod 71. The electrode rod channel 61 is used to pass through the electrode rod 71, thereby covering the electrode 7. An observation window 5 is provided on the top plate of the bellows cover 6. The operating position can be observed through the observation window 5, thereby adjusting the operating position of the robotic arm 3. Specifically, this can be achieved in the following two ways, or other equivalent methods.

[0047] The first method is automatic control. A camera is installed on the overhead crane 10, facing the observation window 5. The camera is used to observe the operating position through the observation window 5. The output of the camera is connected to a PLC controller. The controlled end of the robotic arm 3 is connected to the output of the PLC controller. The PLC controller controls the controlled end of the robotic arm 3 based on the information monitored by the camera, thereby adjusting the operating position so that the electrode rod 71 slides into the electrode rod channel 61, facilitating the electrode lock 8 to lock the electrode rod 71 for gripping the electrode 7. Simultaneously, the controlled end of the bellows cover 6 is connected to the output of the PLC controller so that the bellows cover 6 can be lowered to cover the electrode 7.

[0048] The second method is manual control. The controlled end of the robotic arm 3 is connected to a PLC controller, and the controlled end of the PLC controller is connected to a remote control. The operator observes the operating position through the observation window 5 and uses the remote control to control the controlled end of the robotic arm 3 through the PLC controller, thereby adjusting the operating position so that the electrode rod 71 slides into the electrode rod channel 61, which facilitates the electrode lock 8 to lock the electrode rod 71 and grasp the electrode 7. At the same time, the controlled end of the bellows cover 6 is connected to the output end of the PLC controller, and the bellows cover 6 is lowered to cover the electrode 7.

[0049] An I-shaped exhaust pipe 41 is provided on the top plate of the bellows cover 6. The longitudinal part of the I-shaped exhaust pipe 41 is connected to two horizontal parts. The four openings of the two horizontal parts are bent downward and inserted into the plate to connect with the inner cavity of the bellows cover 6.

[0050] The controlled end of the induced draft fan 1 is connected to the output end of the PLC controller. When the crane 10 moves to the position where the electrode needs to be replaced, the PLC controller turns on the induced draft fan 1. The air inlet of the induced draft fan 1 is connected to the exhaust gas pipe 4. The air inlet of the exhaust gas pipe 4 is connected to the longitudinal part of the I-shaped exhaust gas pipe 41, thereby connecting the air inlet of the induced draft fan 1 to the inner cavity of the bellows cover 6. A negative pressure pipe is set in the upper area. The negative pressure pipe is a retractable negative pressure pipe. One end of the negative pressure pipe is connected to the crane 10, so it can extend and retract with the movement of the crane 10. The air outlet of the induced draft fan 1 is connected to the negative pressure pipe. The end of the negative pressure pipe away from the crane 10 is fixedly connected to a flue gas treatment device, so that the induced draft fan 1 can discharge the dust generated during the process of grabbing the electrode 7 and transporting the electrode 7 into the flue gas treatment device for treatment.

[0051] The lower area also includes an electrode transfer cart 11 and an electrode cooling chamber 13. The electrode cooling chamber 13 is used to cool the replaced electrodes 7 and is equipped with a roller shutter door 14. The electrode transfer cart 11 is located to one side of the roller shutter door 14 and is used to transport the electrodes 7 into the electrode cooling chamber 13. New electrodes are placed next to the electrode transfer cart 11, making it convenient for the overhead crane 10 to place the new electrodes back into the electrolytic cell. The electrode cooling chamber 13 is connected to the flue gas treatment device via an exhaust pipe 12, so that the flue gas generated in the electrode cooling chamber 13 can be discharged into the flue gas treatment device for treatment.

[0052] A flue gas treatment method for replacing electrodes in an electrolytic cell, implemented based on a flue gas treatment system for replacing electrodes in an electrolytic cell, specifically includes the following steps:

[0053] S1: Move the overhead crane 10 to the position where the electrode needs to be replaced, and prepare to extract electrode 7, such as... Figure 1 As shown.

[0054] S2: Open the induced draft fan 1 and the corresponding electrolytic cell cover 9, such as Figure 2 As shown.

[0055] S3: Grab electrode 7.

[0056] Specifically, the robotic arm 3 is manipulated to attach the retracted bellows cover 6 to the electrode 7 to be replaced inside the electrolytic cell, which has already had its cover 9 opened. The operating position is adjusted through the observation window 5, allowing the electrode rod 71 to slide into the electrode rod channel 61. The electrode lock 8 then locks the electrode rod 71 to grasp the electrode 7. Figure 3 As shown.

[0057] S4: Remove electrode 7 from the electrolytic cell, and simultaneously lower the bellows cover 6 to enclose electrode 7. Under the action of the induced draft fan 1, the flue gas is discharged into the flue gas treatment device through the negative pressure pipe, such as... Figure 4 As shown.

[0058] S5: Close the electrolytic cell cover 9, as follows Figure 5 As shown.

[0059] S6: Move electrode 7 to electrode cooling chamber 13, as follows Figure 6 As shown.

[0060] Specifically, the overhead crane 10 places the electrode 7 onto the motor turnover cart 11, and the motor turnover cart 11 carries the electrode 7 into the electrode cooling chamber 13.

[0061] S7: The overhead crane 10 picks up the new electrode and reverses the above steps to place the new electrode into the electrolytic cell, thus completing the electrode replacement.

[0062] In use, the electrolytic cell cover 9 creates an opening 91 that exposes one electrode 7, reducing the risk of excessive flue gas leakage due to an overly large opening 91. A flue gas collection hood allows a robotic arm to directly attach a bellows cover 6 to the electrode 7 at the electrolytic cell opening 91, preventing air leakage. The induced draft fan 1, directly mounted on the overhead crane 10, shortens the airflow distance, improving dust collection efficiency and significantly reducing pollutant emissions during electrode 7 replacement, while also minimizing energy waste. An electrode cooling chamber 13 cools the electrode 7. Connecting the induced draft fan 1 and the electrode cooling chamber 13 to a flue gas treatment device enables centralized flue gas treatment.

Claims

1. A flue gas treatment system for replacing electrodes in an electrolytic cell, comprising an electrolytic cell located in a lower region and an overhead crane (10) moving above the lower region in an upper region; the electrolytic cell contains a plurality of electrodes (7); the overhead crane (10) is equipped with an electrode lock (8) for gripping the electrodes (7) to replace the electrodes (7), characterized in that: The electrolytic cell is provided with a plurality of electrolytic cell cover plates (9) for sealing the electrolytic cell, and opening at least one electrolytic cell cover plate (9) forms an opening (91) that exposes an electrode (7); the overhead crane (10) is provided with a smoke collection hood for collecting flue gas during the replacement of the electrode (7); The smoke collection hood includes an induced draft fan (1) mounted on a crane (10) and a rotatable and bendable mechanical arm (3) mounted on the lower part of the crane (10); the mechanical arm (3) is arranged longitudinally and has a bellows cover (6) at its bottom end that can enter the electrolytic cell through an opening (91) to cover the top and sides of the electrode (7); the top of the bellows cover (6) is provided with an observation window (5); the top of the electrode (7) is provided with an electrode rod (71) that extends out of the electrolytic cell so that the electrode lock (8) can grab the electrode (7); an electrode rod channel (61) for passing through the electrode rod (71) is opened on the side of the bellows cover (6) opposite to the electrode rod (71); the air inlet of the induced draft fan (1) is connected to the inner cavity of the bellows cover (6) through a connected exhaust gas pipe (4), and the air outlet of the induced draft fan (1) is connected to a flue gas treatment device; The lower area is also provided with an electrode cooling chamber (13) for cooling the replaced electrode (7). The electrode cooling chamber (13) is connected to the flue gas treatment device through an exhaust pipe (12). The electrode cooling chamber (13) is provided with a roller shutter door (14). The lower area is provided with an electrode turnover cart (11) located on one side of the roller shutter door (14) for transporting the electrode (7) into the electrode cooling chamber (13). The flue gas treatment method based on the electrolytic cell electrode replacement flue gas treatment system specifically includes the following steps: S1: Move the overhead crane (10) to the position where the electrode needs to be replaced, and prepare to extract the electrode (7). S2: Open the induced draft fan (1) and the corresponding electrolytic cell cover (9); S3: Grab the electrode (7); Specifically, step S3 involves manipulating the robotic arm (3) to attach the retracted bellows cover (6) to the electrode (7) that needs to be replaced inside the electrolytic cell where the electrolytic cell cover plate (9) has been opened, adjusting the operating position through the observation window (5), so that the electrode rod (71) slides into the electrode rod channel (61), and the electrode lock (8) locks the electrode rod (71) to grab the electrode (7). S4: Remove the electrode (7) from the electrolytic cell and at the same time lower the bellows cover (6) to wrap the electrode (7). Under the action of the induced draft fan (1), the smoke and dust are discharged into the flue gas treatment device through the negative pressure pipe. S5: Close the electrolytic cell cover (9); S6: Move the electrode (7) to the electrode cooling chamber (13). Specifically, step S6 involves the overhead crane (10) placing the electrode (7) onto the electrode turnover cart (11) and sliding it into the electrode cooling chamber (13). S7: The overhead crane (10) grabs the new electrode and reverses the above steps to place the new electrode into the electrolytic cell to complete the electrode replacement.

2. The flue gas treatment system for replacing electrodes in an electrolytic cell according to claim 1, characterized in that: The top of the bellows cover (6) is a rigid plate and is connected to the bottom of the robotic arm (3). The plate is surrounded by a bellows cover body that can extend downward to surround the electrode (7). The top of the plate is provided with an I-shaped exhaust pipe (41). The longitudinal part of the I-shaped exhaust pipe (41) and the two transverse parts are connected. The four openings of the two transverse parts are bent downward and inserted into the plate and connected to the inner cavity of the bellows cover (6). The air inlet of the exhaust pipe (4) is connected to the longitudinal part of the I-shaped exhaust pipe (41).

3. The flue gas treatment system for replacing electrodes in an electrolytic cell according to claim 1, characterized in that: The bellows cover (6) is provided with steel wires arranged along the extension direction of the bellows cover (6). A winch is connected to the top of the steel wires. The controlled end of the winch is connected to a bellows cover motor for driving the winch to wind up and unwind the steel wires to realize the contraction and extension of the bellows cover (6).

4. The flue gas treatment system for replacing electrodes in an electrolytic cell according to claim 1, characterized in that: The overhead crane (10) is equipped with a camera for observing the operation position through the observation window (5), and the output end of the camera is connected to a PLC controller; the controlled ends of the robotic arm (3), the blower (1) and the bellows cover (6) are respectively connected to the output end of the PLC controller.

5. The flue gas treatment system for replacing electrodes in an electrolytic cell according to claim 1, characterized in that: The upper area is provided with a negative pressure pipe that can extend and retract as the crane (10) moves; the air outlet of the induced draft fan (1) is connected to the negative pressure pipe, and the end of the negative pressure pipe away from the crane (10) is fixedly connected to the flue gas treatment device.

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