Device for balancing negative pressure of smoke tube of electrolytic cell and control method

Abstract

The invention discloses a device for balancing the negative pressure of electrolytic bath smoke tubes and a control method, the device comprises a main smoke tube and a negative pressure balancing tube, the main smoke tube is provided with a plurality of branch smoke tubes, the plurality of branch smoke tubes are connected with a plurality of electrolytic baths one by one, and each branch smoke tube is provided with a branch smoke tube regulating valve and a negative pressure sensor; a plurality of negative pressure balance branch pipes are mounted on the negative pressure balance pipe, the plurality of negative pressure balance branch pipes are connected with the plurality of smoke pipes one by one, and negative pressure balance adjusting valves are mounted on the negative pressure balance branch pipes; and the negative pressure balance regulating valve is controlled by a control system. The control system is connected with the negative pressure sensor so as to obtain negative pressure data. The device can automatically balance the negative pressure difference between the cells, improves the gas collection efficiency of the electrolytic cell, and reduces the single-cell smoke discharge amount of the electrolytic cell and the energy consumption of a purification system. And the negative pressure adjusting difficulty of the electrolytic cell main smoke pipe can be greatly reduced. When the groove cover plate is opened for pole changing operation, the system can automatically perform negative pressure balance, the efficiency of the purification system is improved, and the gas collection effect is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of negative pressure gas collection, in particular to a device for balancing the negative pressure of electrolytic cell flue pipes and a control method. BACKGROUND

[0002] The flue pipe of an aluminum electrolytic cell is an important component of an aluminum electrolytic production system. During the aluminum electrolytic process, a large amount of waste gas containing fluorides and sulfur dioxide is generated. The flue pipe collects the waste gas from the electrolytic cell through the exhaust branch pipes connected to the electrolytic cell and sends the waste gas to a purification system for treatment.

[0003] The flue pipe is usually arranged in accordance with the structure of the electrolytic cell to ensure that the waste gas generated by each electrolytic cell can smoothly enter the flue pipe. Due to the uneven negative pressure of the flue pipe between the electrolytic cells, it is difficult to achieve satisfactory gas collection effect. SUMMARY

[0004] The present application aims to provide a device for balancing the negative pressure of electrolytic cell flue pipes and a control method, which can homogenize the negative pressure of the flue pipe between the electrolytic cells and ensure good gas collection effect of the electrolytic cell.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solution: a device for balancing the negative pressure of electrolytic cell flue pipes, comprising a main flue pipe and a negative pressure balancing pipe, a plurality of branch flue pipes are installed on the main flue pipe, and the plurality of branch flue pipes are connected to the plurality of electrolytic cells one by one, a branch flue pipe regulating valve and a negative pressure sensor are installed on the branch flue pipe, a plurality of negative pressure balancing branch pipes are installed on the negative pressure balancing pipe, and the plurality of negative pressure balancing branch pipes are connected to the plurality of branch flue pipes one by one, and a negative pressure balancing regulating valve is installed on the negative pressure balancing branch pipe, the negative pressure balancing regulating valve is controlled by a control system, and the control system is connected to the negative pressure sensor and obtains negative pressure data.

[0006] Preferably, a dust settling pipe is arranged at the connection between the negative pressure balancing branch pipe and the branch flue pipe.

[0007] Preferably, the diameter of the dust settling pipe is greater than that of the negative pressure balancing branch pipe.

[0008] The present application also provides a control method, in which the control system sends an electrically operated execution signal to control the opening degree of the negative pressure balancing regulating valve according to the negative pressure feedback signal collected by the negative pressure sensor.

[0009] Preferably, the control system calculates the negative pressure difference based on the negative pressure values of the branch flue pipes collected by the negative pressure sensor. According to the relationship between the negative pressure difference and the set value, the control system sends an instruction to the branch flue pipe regulating valve to adjust the gear position and opening degree of the negative pressure balancing regulating valve.

[0010] Preferably, the corresponding relationship between the opening degree and the gear position of the negative pressure balancing regulating valve is that When the negative pressure difference < 5Pa, it is 1 gear, that is, the corresponding opening is 0°; When 5Pa ≤ negative pressure difference < 15Pa, it is 2 gear, that is, the corresponding opening is 15°; When 15Pa ≤ negative pressure difference < 25Pa, it is 3 gear, that is, the corresponding opening is 30°; When 25Pa ≤ negative pressure difference < 35Pa, it is 4 gear, that is, the corresponding opening is 45°; When 35Pa ≤ negative pressure difference < 45Pa, it is 5 gear, that is, the corresponding opening is 60°; When 45Pa ≤ negative pressure difference < 55Pa, it is 6 gear, that is, the corresponding opening is 75°; When 55Pa ≤ negative pressure difference, it is 7 gear, that is, the corresponding opening is 90° Compared with the prior art, the beneficial effects of the present application are: By setting the negative pressure sensor, the negative pressure balance regulating valve and the control system and other mechanisms, the negative pressure difference between each groove can be automatically balanced, the gas collection efficiency of the electrolytic cell is improved, and the smoke exhaust volume of the electrolytic cell and the energy consumption of the purification system are reduced.

[0011] And by setting the opening and gear operation logic of a set of negative pressure balance regulating valves, the electrolytic cell flue can be automatically balanced, the negative pressure adjustment difficulty of the electrolytic cell main flue can be greatly reduced, the purification system efficiency can be improved, and the gas collection effect can be ensured. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is a schematic view of the device for balancing the negative pressure of the electrolytic cell flue.

[0013] 1, main flue; 2, negative pressure balance pipe; 3, branch flue; 4, negative pressure balance branch pipe; 5, negative pressure balance regulating valve; 6, branch flue regulating valve; 7, dust settling pipe; 8, negative pressure sensor. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0015] Please refer to Figure 1The application provides a technical scheme: a device for balancing negative pressure of a flue of an electrolytic cell, comprising a main flue 1 and a negative pressure balancing pipe 2, wherein the main flue 1 is connected to a purification system to treat waste gas, a plurality of branch flues 3 are installed on the main flue 1, and the plurality of branch flues 3 are connected to a plurality of electrolytic cells one by one, and a branch flue adjusting valve 6 and a negative pressure sensor 8 are installed on the branch flue 3.

[0016] A plurality of negative pressure balancing branch pipes 4 are installed on the negative pressure balancing pipe 2, and the plurality of negative pressure balancing branch pipes 4 are connected to the plurality of branch flues 3 one by one, and a negative pressure balancing adjusting valve 5 is installed on the negative pressure balancing branch pipe 4.

[0017] The negative pressure balancing adjusting valve 5 and the negative pressure sensor 8 are connected to a control system through a cable or a control cable to obtain negative pressure information and control the opening degree of the negative pressure balancing adjusting valve 5, so as to achieve the purpose of negative pressure balancing. A dust settling pipe 7 is arranged at the connection position of the negative pressure balancing branch pipe 4 and the branch flue 3, and the diameter of the dust settling pipe 7 is greater than that of the negative pressure balancing branch pipe 4. The dust settling pipe 7 has a large diameter, and the upward wind speed at this position is low, so that the dust in the upward flue gas is quickly settled, and the risk of ash blocking of the negative pressure balancing branch pipe 4 is reduced.

[0018] The application also provides a control method, wherein the control system sends an electrically-driven execution signal to control the opening degree of the negative pressure balancing adjusting valve 5 according to the negative pressure feedback signal collected by the negative pressure sensor 8. The control system calculates the negative pressure difference according to the negative pressure values of the branch flues 3 collected by the negative pressure sensor 8. According to the relationship between the negative pressure difference and the set value, the control system sends an instruction to the branch flue adjusting valve 6 to adjust the gear position and the opening degree of the negative pressure balancing adjusting valve 5.

[0019] The corresponding relationship between the opening degree and the gear position of the negative pressure balancing adjusting valve 5 is as follows When the negative pressure difference is less than 5 Pa, the gear position is 1, and the corresponding opening degree is 0°; When 5 Pa≤ the negative pressure difference < 15 Pa, the gear position is 2, and the corresponding opening degree is 15°; When 15 Pa≤ the negative pressure difference < 25 Pa, the gear position is 3, and the corresponding opening degree is 30°; When 25 Pa≤ the negative pressure difference < 35 Pa, the gear position is 4, and the corresponding opening degree is 45°; When 35 Pa≤ the negative pressure difference < 45 Pa, the gear position is 5, and the corresponding opening degree is 60°; When 45 Pa≤ the negative pressure difference < 55 Pa, the gear position is 6, and the corresponding opening degree is 75°; When 55 Pa≤ the negative pressure difference, the gear position is 7, and the corresponding opening degree is 90°.

[0020] After all the electrolytic cells are put into production, the negative pressure of each cell needs to be adjusted to ensure that the negative pressure difference between the adjacent cells is 10-15 Pa. Before the adjustment, all the negative pressure balance adjustment valves 5 in the system need to be closed. After the above adjustment is completed, the negative pressure balance automatic adjustment control system is opened. The control system will automatically adjust the opening degree of the negative pressure balance adjustment valve 5 according to the negative pressure difference to make the negative pressure between the cells tend to be balanced.

[0021] Finally, it should be noted that the above only describes the preferred embodiments of the present application and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent replacements to some technical features, as long as they are within the spirit and principles of the present application. Any modification, equivalent replacement, improvement, etc. made within the scope of the present application should be included in the protection scope of the present application.

Claims

1. A device for balancing the negative pressure in the flue gas pipe of an electrolytic cell, characterized in that: It includes a main smoke pipe (1) and a negative pressure balance pipe (2). Several branch smoke pipes (3) are installed on the main smoke pipe (1), and the several branch smoke pipes (3) are connected to several electrolytic cells one by one. A branch smoke pipe regulating valve (6) and a negative pressure sensor (8) are installed on the branch smoke pipe (3). The negative pressure balance pipe (2) is equipped with several negative pressure balance branch pipes (4), and the several negative pressure balance branch pipes (4) are connected to several branch pipes (3) one by one, and a negative pressure balance regulating valve (5) is installed on the negative pressure balance branch pipe (4). The negative pressure balance regulating valve (5) is controlled by the control system, which is connected to the negative pressure sensor (8) and acquires negative pressure data.

2. The device for balancing the negative pressure of the electrolytic cell flue pipe according to claim 1, characterized in that: A dust settling pipe (7) is provided at the connection between the negative pressure balance branch pipe (4) and the branch smoke pipe (3).

3. The device for balancing the negative pressure of the electrolytic cell flue pipe according to claim 2, characterized in that: The diameter of the dust settling pipe (7) is larger than that of the negative pressure balance branch pipe (4).

4. A control method for the device as described in claim 1, characterized in that: The control system sends an electric actuator signal to control the opening degree of the negative pressure balance regulating valve (5) based on the negative pressure feedback signal collected by the negative pressure sensor (8).

5. The control method according to claim 4, characterized in that: The control system calculates the negative pressure difference based on the negative pressure values ​​of each cigarette pipe (3) collected by the negative pressure sensor (8); Based on the relationship between the negative pressure difference and the set value, the control system issues a command to the branch pipe regulating valve (6) to adjust the position and opening of the negative pressure balance regulating valve (5).

6. The control method according to claim 5, characterized in that: The specific relationship between the opening degree and the gear position of the negative pressure balance regulating valve (5) is as follows: When the negative pressure difference is less than 5Pa, it is position 1, which corresponds to an opening degree of 0°. When 5Pa≤negative pressure difference<15Pa, it is position 2, which corresponds to an opening degree of 15°; When 15Pa≤negative pressure difference<25Pa, it is position 3, which corresponds to an opening degree of 30°; When 25Pa≤negative pressure difference<35Pa, it is position 4, which corresponds to an opening degree of 45°; When 35Pa≤negative pressure difference<45Pa, it is position 5, which corresponds to an opening degree of 60°; When 45Pa≤negative pressure difference<55Pa, it is position 6, which corresponds to an opening degree of 75°; When 55Pa ≤ negative pressure difference, it is position 7, which corresponds to an opening degree of 90°.

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