Dedusting system for converter steelmaking and automatic control method

Abstract

The invention discloses a dust removal system for converter steelmaking and an automatic control method. The dust removal system comprises a dust removal collecting cover, an adjusting valve, a filter cartridge dust remover, an air volume detector, a main fan, a chimney, a flue and a control unit. The control unit collects the converter steelmaking process state and determines the current converter steelmaking process stage; determining the valve opening of the regulating valve at the collecting cover according to the process stage of the converter; calculating the total opening degree of all the valves; due to the fact that the total opening degree of the valve and the output air volume of the fan are in linear relation, the air volume value needing to be output by the fan can be calculated. And the value and a value measured by an air volume detector arranged at the inlet of the dust remover are subjected to PI regulation control in a controller, and a fan is controlled to output a corresponding rotating speed. The rotating speed of the dust removal fan can be automatically and accurately controlled, compared with a traditional dust removal control mode, the energy loss and the operation workload of personnel are greatly reduced, the service life of equipment is prolonged, the control precision is improved, and safety and environment friendliness are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of dust removal control, and in particular to a dust removal system and an automatic control method for converter steelmaking. Background Art

[0002] Converter steelmaking is to blow oxygen into molten pig iron to oxidize impurities such as silicon and manganese. The main technical means used include oxygen supply, slag making, heating, adding deoxidizers and alloying operations. The specific process is:

[0003] 1) Steel tapping and slag removal from furnace;

[0004] 2) Tilt the furnace, add scrap steel and molten iron;

[0005] 3) Lower the gun and start blowing, and add the first batch of slag at the same time;

[0006] 4) After 3 to 5 minutes, add the second batch of slag and continue blowing;

[0007] 5) Turn over the furnace, measure temperature and take samples;

[0008] 6) Steel is tapped and deoxidation and alloying is carried out simultaneously.

[0009] As we all know, the main working principle of steelmaking dust removal is: the smoke generated by steelmaking is sucked into the dust removal system, filtered by the bag filter until the smoke reaches the national emission standard, and then discharged into the atmosphere through the chimney. It is mainly to filter the dust in the smoke. In the second and third smoke dust removal processes produced in traditional converter steelmaking, the steelmaking operator sets the fan speed and valve opening according to the amount of smoke in the steelmaking plant and the empirical value. Due to the traditional manual operation, it is easy to cause the fan's air volume to be insufficient to collect the smoke in the steelmaking plant, resulting in the dust removal effect not meeting the environmental protection requirements, and even the leakage of smoke in the plant, causing damage to the atmospheric environment; or because the air volume is set too high, it causes an unnecessary waste of electricity. Summary of the invention

[0010] The purpose of the present invention is to provide a dust removal system and automatic control method for converter steelmaking, which can reduce the amount of human operation, improve control accuracy, save energy consumption, be safe and environmentally friendly, and solve the shortcomings of steelmaking dust removal personnel operation control in the prior art.

[0011] To achieve the above object, the present invention provides the following technical solutions:

[0012] A dust removal system for converter steelmaking, comprising a dust collection hood, a regulating valve, a cartridge dust collector, an air volume detector, a main fan, a chimney, a flue and a control unit; the flue is used to connect the dust collection hood, the cartridge dust collector and the chimney, the flue is arranged between the dust collection hood and the cartridge dust collector, and between the cartridge dust collector and the chimney, the chimney is used to discharge clean flue gas into the atmosphere; the regulating valve is installed on the flue behind the dust collection hood; the air volume detector is installed on the flue at the air inlet of the cartridge dust collector; the main fan is installed on the flue at the air outlet of the cartridge dust collector; the regulating valve, the air volume detector and the main fan are electrically connected to the control unit respectively, and are controlled by the control unit.

[0013] Furthermore, the control unit is an external computer terminal for collecting parameters of each stage of the converter steelmaking process in real time.

[0014] Furthermore, the control unit sets the opening of the regulating valves in each steelmaking process stage in advance through a programming program. The control unit opens the regulating valves in front of the furnace and at the charging yard collection point according to the preset opening values ​​based on the collected steelmaking process stages.

[0015] Furthermore, the control unit may receive a feedback signal of the opening of the regulating valve and calculate the total opening of the regulating valves at all collection locations.

[0016] Furthermore, the total opening of the regulating valve is linearly related to the air volume output by the main fan, and the total opening of the regulating valve is used to determine the air volume value that the main fan needs to output.

[0017] Furthermore, the air volume value required to be output by the main fan and the air volume value signal detected by the air volume detector are fed back to the control unit, and the control unit outputs the corresponding rotation speed to the main fan through PI control calculation.

[0018] Furthermore, the main fan sends the flue gas containing a large amount of dust generated during converter steelmaking into the cartridge dust collector for filtration according to the flue gas volume in the flue, and discharges the flue gas into the atmosphere through the chimney.

[0019] The present invention provides a new technical solution: an automatic control method for a dust removal system for converter steelmaking, comprising the following steps:

[0020] S1: Preset the opening of the regulating valve behind each dust collection hood at different stages of steelmaking in advance according to the different amounts of smoke generated at different stages of steelmaking;

[0021] S2: Dust removal starts, and the process stage signal of the steelmaking control system is collected through the control unit;

[0022] S3: according to the collected process signal, the regulating valve behind the dust collection hood is opened according to the preset value;

[0023] S4: The control unit collects the opening of each regulating valve and calculates the total opening value of all regulating valves. The total valve opening value is linearly related to the output air volume of the main fan, and then calculates the required air volume of the main fan corresponding to any total valve opening;

[0024] S5: The air volume value corresponding to the total opening value is used as the set value of this stage, and the air volume detector at the inlet of the cartridge dust collector is used as the feedback value to perform PI regulation control in the control unit;

[0025] S6: The air volume value required to be output by the main fan is obtained by PI regulation, converted into the fan speed value, and then output to the fan for execution;

[0026] S7: The air volume obtained at each collection point brings the smoke and dust collected into the dust removal system, and after being filtered by the cartridge dust collector, it is discharged into the atmosphere through the chimney.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The dust removal system and automatic control method for converter steelmaking of the present invention collects process status through a control unit, determines the valve opening size of each collection point, and ensures that the air volume provided by the fan is reasonably distributed. The total valve opening allows the fan to provide an accurate air volume, which can ensure sufficient air volume demand, while saving unnecessary energy waste, so that the equipment will not work at high load for a long time, increase the service life of the equipment, reduce the amount of personnel operation, improve control accuracy, save energy consumption, and be safe and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is the equipment configuration diagram of the dust removal system of the present invention;

[0030] Figure 2 This is a flow chart of the control method of the present invention.

[0031] In the figure: 1. Dust collection hood; 2. Regulating valve; 3. Cartridge dust collector; 4. Air volume detector; 5. Main fan; 6. Chimney; 7. Flue. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] See also Figure 1A dust removal system for converter steelmaking provided by an embodiment of the present invention comprises a dust collection hood 1, a regulating valve 2, a cartridge dust collector 3, an air volume detector 4, a main fan 5, a chimney 6, a flue 7 and a control unit; the flue 7 is used to connect the dust collection hood 1, the cartridge dust collector 3 and the chimney 6, and the flue 7 is arranged between the dust collection hood 1 and the cartridge dust collector 3, and between the cartridge dust collector 3 and the chimney 6, and the chimney 6 is used to discharge clean flue gas into the atmosphere; the regulating valve 2 is installed on the flue 7 behind the dust collection hood 1; the air volume detector 4 is installed on the flue 7 at the air inlet of the cartridge dust collector 3; the main fan 5 is installed on the flue 7 at the air outlet of the cartridge dust collector 3; the regulating valve 2, the air volume detector 4 and the main fan 5 are electrically connected to the control unit respectively and are controlled by the control unit.

[0034] In the above embodiment, the above-mentioned equipment of the chimney 6 is connected in sequence by the flue 7, and finally the clean flue gas is discharged into the atmosphere by the chimney 6. The control unit is an external computer terminal, which is used to collect the parameters of each stage of the converter steelmaking process in real time; the control unit sets the opening of the regulating valve 2 of each process stage of steelmaking in advance through a programming program, and the control unit opens the regulating valve 2 at the front of the furnace and the charging field according to the preset opening value according to the collected steelmaking process stage; the control unit can receive the feedback signal of the opening of the regulating valve 2, and calculate the opening of all the regulating valves at the collection site. The total opening of the throttle valve 2; the total opening of the regulating valve 2 is linearly related to the output air volume of the main fan 5, and the total opening of the regulating valve 2 is used to determine the air volume value that the main fan 5 needs to output; the air volume value output by the main fan 5 and the air volume value signal detected by the air volume detector 4 are fed back to the control unit, and the control unit outputs the corresponding speed to the main fan 5 through PI control calculation; the main fan 5 sends the flue gas containing a large amount of dust generated during converter steelmaking into the cartridge dust collector 3 for filtration according to the flue gas volume of the flue 7, and discharges it into the atmosphere through the chimney 6.

[0035] For details, please refer to Figure 2 In order to solve the problem that the dust removal fan automatically follows the process stage of steelmaking, accurately changes the rotation speed, and then changes the air volume. It prevents the energy waste or smoke leakage caused by excessive or insufficient air volume due to human operation. The embodiment of the present invention also provides an automatic control method for the dust removal system of converter steelmaking, including the following steps:

[0036] S1: Preset the opening of the regulating valve 2 behind each dust collection hood 1 at different process stages of steelmaking in advance according to the different amounts of smoke generated at different stages of steelmaking;

[0037] S2: Dust removal starts, and the process stage signal of the steelmaking control system is collected through the control unit;

[0038] S3: according to the collected process signal, the regulating valve 2 behind the dust collection cover 1 is opened according to the preset value;

[0039] S4: The control unit collects the opening of each regulating valve 2 and calculates the total opening value of all regulating valves. The total valve opening value is linearly related to the output air volume of the main fan 5, and then calculates the required air volume of the main fan 5 corresponding to any total valve opening;

[0040] S5: The air volume value corresponding to the total opening value is used as the set value of this stage, and the air volume detector 4 at the inlet of the cartridge dust collector 3 is used as the feedback value to perform PI regulation control in the control unit;

[0041] S6: The air volume value required to be output by the main fan 5 is obtained by PI regulation, converted into the fan speed value, and then output to the fan for execution;

[0042] S7: The smoke and dust collected at each collection point is brought into the dust removal system through the air volume obtained at each collection point, and after being filtered by the cartridge dust collector 3, it is discharged into the atmosphere through the chimney 6.

[0043] Working principle: In the embodiment of the present invention, since the smoke and dust generated at different stages of steelmaking are different, the different openings of the regulating valves 2 behind each dust collection hood 1 are preset in advance according to the stage of steelmaking. Through the data exchange between the dust removal control unit and the steelmaking control system, the current process stage of the steelmaking process can be known. Therefore, the regulating valves 2 of each collection point are opened according to the previous valve opening preset value, and the air volume is mainly allocated to each collection point at this time. After receiving the feedback signal of the opening of each collection valve through the control unit, the sum of the valve openings of all collection points at this time is calculated. The total valve opening is linearly related to the output air volume of the fan, and the air volume required by the dust removal system at this steelmaking stage can be calculated. The inlet end of the cartridge dust collector 3 collects the flue air volume as the system feedback value, and an accurate air volume value can be obtained through the PI adjustment calculation of the control system. As we all know, the fan air volume is linearly related to the fan impeller speed. The control unit outputs the speed command to the main fan 5 for execution. At this time, each collection point will obtain a suitable air volume, which can have a good collection effect on the smoke and dust.

[0044] In summary, the dust removal system and automatic control method for converter steelmaking of the present invention collects process status through the control unit, determines the valve opening size of each collection point, and ensures that the air volume provided by the fan is reasonably distributed. The total valve opening allows the fan to provide an accurate air volume, which can ensure sufficient air volume demand, while saving unnecessary energy waste, so that the equipment will not work at high load for a long time, increase the service life of the equipment, reduce the amount of personnel operation, improve the control accuracy, save energy consumption, and be safe and environmentally friendly.

[0045] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A dust removal system for converter steelmaking, characterized in that: The invention comprises a dust collecting hood (1), a regulating valve (2), a filter cartridge dust collector (3), an air volume detector (4), a main fan (5), a chimney (6), a flue (7) and a control unit; the flue (7) is used to connect the dust collecting hood (1), the filter cartridge dust collector (3) and the chimney (6); the flue (7) is arranged between the dust collecting hood (1) and the filter cartridge dust collector (3), and between the filter cartridge dust collector (3) and the chimney (6); the chimney (6) is used to Clean flue gas is discharged into the atmosphere; the regulating valve (2) is installed on the flue (7) behind the dust collection hood (1); the air volume detector (4) is installed on the flue (7) at the air inlet of the cartridge dust collector (3); the main fan (5) is installed on the flue (7) at the air outlet of the cartridge dust collector (3); the regulating valve (2), the air volume detector (4) and the main fan (5) are respectively electrically connected to a control unit and are controlled by the control unit.

2. A dust removal system for converter steelmaking as claimed in claim 1, characterized in that: The control unit is an external computer terminal, which is used to collect parameters of each stage of the converter steelmaking process in real time.

3. A dust removal system for converter steelmaking as claimed in claim 2, characterized in that: The control unit sets the opening of the regulating valve (2) at each steelmaking process stage in advance through a programming program. The control unit opens the regulating valve (2) in front of the furnace and at the charging field collection point according to the preset opening value based on the collected steelmaking process stage.

4. A dust removal system for converter steelmaking as claimed in claim 3, characterized in that: The control unit can receive a feedback signal of the opening of the regulating valve (2) and calculate the total opening of all the regulating valves (2) at the collection points.

5. A dust removal system for converter steelmaking as claimed in claim 4, characterized in that: The total opening of the regulating valve (2) is linearly related to the air volume output by the main fan (5), and the total opening of the regulating valve (2) is used to determine the air volume value that the main fan (5) needs to output.

6. A dust removal system for converter steelmaking as claimed in claim 5, characterized in that: The air volume value required to be output by the main fan (5) and the air volume value signal detected by the air volume detector (4) are fed back to the control unit, and the control unit outputs the corresponding rotation speed to the main fan (5) through PI control calculation.

7. A dust removal system for converter steelmaking as claimed in claim 6, characterized in that: The main fan (5) sends the flue gas containing a large amount of dust generated during converter steelmaking into the cartridge dust collector (3) for filtration according to the flue gas volume of the flue (7), and discharges it into the atmosphere through the chimney (6).

8. An automatic control method for a dust removal system for converter steelmaking according to claim 7, characterized in that: The following steps are involved: S1: presetting the opening of the regulating valve (2) behind each dust collection hood (1) at different stages of steelmaking process according to the different amounts of smoke generated at different stages of steelmaking; S2: Dust removal starts, and the process stage signal of the steelmaking control system is collected through the control unit; S3: opening the regulating valve (2) behind the dust collection cover (1) according to the collected process signal according to a preset value; S4: The control unit collects the opening of each regulating valve (2) and calculates the total opening value of all regulating valves. The total valve opening value is linearly related to the output air volume of the main fan (5), and then calculates the required air volume of the main fan (5) corresponding to any total valve opening; S5: The air volume value corresponding to the total opening value is used as the set value of this stage, and the air volume detector (4) at the inlet of the cartridge dust collector (3) is used as the feedback value to perform PI regulation control in the control unit; S6: The air volume value required to be output by the main fan (5) is obtained by PI regulation, converted into a fan speed value, and then output to the fan for execution; S7: The smoke and dust collected at each collection point is brought into the dust removal system through the air volume obtained at each collection point, and after being filtered by the cartridge dust collector (3), it is discharged into the atmosphere through the chimney (6).

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