Intelligent sulfuric acid adding device for circulating water and control method thereof

Abstract

The application discloses a circulating water intelligent sulfuric acid adding device and a control method thereof, which comprises a sulfuric acid storage tank, a cooling tower pool, a circulating water supplement water pipeline, a circulating water drainage pipeline, an intelligent wind speed, temperature and humidity measuring instrument and a mechanical ventilation cooling tower; the outlet of the sulfuric acid storage tank is communicated with the cooling tower pool, the circulating water supplement water pipeline is communicated with the cooling tower pool, a cooling tower pool liquid level meter is arranged in the cooling tower pool, the bottom outlet of the cooling tower pool is communicated with the circulating water drainage pipeline, the cooling tower pool is located below the mechanical ventilation cooling tower, and the intelligent wind speed, temperature and humidity measuring instrument is arranged at the side of the mechanical ventilation cooling tower. The device and the control method thereof can effectively control the pH and alkalinity of the circulating cooling water in the set value range under the automatic operation state, keep the circulating cooling water quality stable, and ensure the stability of the cooling tower pool liquid level.

Description

Technical Field

[0001] This invention belongs to the field of circulating cooling water treatment in thermal power plants, and relates to an intelligent sulfuric acid dosing device for circulating water and its control method. Background Technology

[0002] To protect increasingly scarce water resources, it is of great significance to thoroughly implement the national water conservation action, continuously promote industrial water conservation and emission reduction, and improve water use efficiency in order to protect the human living environment.

[0003] Thermal power plants are major water consumers, especially wet-cooled units, where circulating cooling water accounts for more than 80% of the total water consumption of the power plant. High water consumption and low reuse rate are key factors for power plants to achieve water conservation and emission reduction.

[0004] Under the severe situation of water conservation and emission reduction, the operation of circulating cooling water with high concentration ratio and the use of multiple water sources have gradually become the norm, and the circulating water system faces more severe scaling and corrosion risks.

[0005] Existing patent applications use pH value as the sole indicator for determining the addition of sulfuric acid to circulating cooling water. However, due to the extensive operation and management of circulating water systems in most power plants in China, manual operation is still used for circulating water dosing, sewage discharge, and laboratory monitoring. As a result, water quality monitoring results are significantly delayed, increasing the risk of corrosion and scaling in the circulating water system. At the same time, there is varying degrees of waste of water resources and water treatment agents. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a circulating water intelligent sulfuric acid dosing device and its control method. The device and its control method can effectively control the pH and alkalinity of the circulating cooling water within the set value range in automatic operation to maintain the stability of the circulating cooling water quality, while ensuring the stability of the cooling tower pool liquid level.

[0007] To achieve the above objectives, the present invention discloses an intelligent circulating water sulfuric acid dosing device, including a sulfuric acid storage tank, a cooling tower pool, a circulating water makeup water pipeline, a circulating water drainage pipeline, an intelligent wind speed, temperature and humidity measuring instrument, and a mechanical ventilation cooling tower.

[0008] The outlet of the sulfuric acid storage tank is connected to the cooling tower pool, the circulating water makeup water pipe is connected to the cooling tower pool, a cooling tower pool level gauge is installed in the cooling tower pool, the bottom outlet of the cooling tower pool is connected to the circulating water drainage pipe, the cooling tower pool is located below the mechanical ventilation cooling tower, and an intelligent wind speed, temperature and humidity measuring instrument is installed on the side of the mechanical ventilation cooling tower.

[0009] Furthermore, the outlet of the sulfuric acid storage tank is connected to the cooling tower pool via a filter, a booster pump inlet valve, a booster pump, a booster pump outlet valve, a sulfuric acid regulating valve, a sulfuric acid pipeline flow meter, a sulfuric acid electric protection valve, and a sulfuric acid pipeline check valve.

[0010] Furthermore, a bypass valve for the sulfuric acid regulating valve is connected in parallel with the sulfuric acid regulating valve.

[0011] Furthermore, the branch formed by the booster pump inlet valve, the booster pump, and the booster pump outlet valve is connected in parallel to a booster pump bypass valve.

[0012] Furthermore, the circulating water is divided into two paths after passing through the circulating water makeup water regulating valve. One path is connected to the cooling tower pool via a circulating water makeup water flow meter, and the other path is connected to the cooling tower pool via a circulating water makeup water sampling valve. An online pH meter and an online alkalinity meter for the circulating water makeup water are installed between the circulating water makeup water sampling valve and the cooling tower pool. The online pH meter and the online alkalinity meter for the circulating water makeup water are connected in parallel.

[0013] Furthermore, it also includes a sulfuric acid storage tank level gauge, which is connected to the sulfuric acid storage tank through valves on the upper and lower parts of the level gauge.

[0014] Furthermore, the bottom outlet of the cooling tower pool is connected to the circulating water drainage pipe via a circulating water drainage regulating valve and a circulating water drainage flow meter, and the circulating water drainage regulating valve is connected in parallel with a circulating water drainage regulating valve bypass valve.

[0015] Furthermore, the bottom outlet of the cooling tower pool is connected to the circulating water drainage pipeline via a circulating water drainage sampling valve, an online pH meter for circulating water drainage, and an online alkalinity meter for circulating water drainage. The online pH meter for circulating water drainage and the online alkalinity meter for circulating water drainage are connected in parallel.

[0016] Furthermore, the PLC controller is electrically connected to the circulating water makeup water regulating valve, circulating water makeup water flow meter, circulating water makeup water online pH meter, circulating water makeup water online alkalinity meter, intelligent wind speed, temperature and humidity measuring instrument, cooling tower pool level gauge, circulating water drainage online pH meter, circulating water drainage online alkalinity meter, circulating water drainage regulating valve, circulating water drainage flow meter, sulfuric acid storage tank level gauge, booster pump, sulfuric acid regulating valve, sulfuric acid pipeline flow meter, and sulfuric acid electric protection valve.

[0017] This invention discloses a control method for an intelligent sulfuric acid dosing device for circulating water, comprising the following steps:

[0018] The pH setpoint of the cooling tower pool's circulating water minus the value measured by the online pH meter of the circulating water drainage is used as the error input for the pH-PID method. A weighting system K1 is then used for proportional allocation to obtain the pH weighting parameter K11. Similarly, the alkalinity setpoint of the cooling tower pool's circulating water minus the value measured by the online alkalinity meter of the circulating water drainage is used as the error input for the alkalinity-PID algorithm. A weighting system K2 is then used for proportional allocation to obtain the alkalinity weighting parameter K12. The opening of the circulating water drainage regulating valve is controlled based on the sum of the pH weighting parameter K11 and the alkalinity weighting parameter K12 to regulate the circulating water drainage volume.

[0019] The result of subtracting the value measured by the cooling tower pool level gauge from the setpoint of the cooling tower pool level is used as the error input of the level-PID method; the intelligent wind speed, temperature and humidity measuring instrument retrieves the real-time water database of the circulating cooling water system to view the instantaneous loss DW; the opening of the circulating water makeup water regulating valve is controlled according to the output result of the level-PID algorithm, the instantaneous loss DW and the cumulative result of the value measured by the circulating water drainage flow meter, so as to regulate the amount of circulating water makeup water;

[0020] The pH difference is obtained by processing the values ​​measured by the online pH meters of the circulating water drainage and circulating water makeup water, as well as the pH setpoint of the circulating water in the cooling tower pool, through intelligent data processing and control unit. Similarly, the alkalinity difference is obtained by processing the values ​​measured by the online alkalinity meters of the circulating water makeup water and circulating water drainage, as well as the alkalinity setpoint of the circulating water in the cooling tower pool, through intelligent data processing and control unit. Using the values ​​measured by the circulating water makeup water flow meter, the pH difference, and the alkalinity difference as input signals, the opening of the sulfuric acid regulating valve is controlled by an automatic sulfuric acid addition control model to adjust the amount of sulfuric acid added to the circulating water.

[0021] When the value measured by the online pH meter of the circulating water drainage is less than the pH setting value of the circulating water in the cooling tower pool, the value measured by the online alkalinity meter of the circulating water drainage is less than the alkalinity setting value of the circulating water in the cooling tower pool, or the value measured by the sulfuric acid pipeline flow meter is greater than the maximum allowable acid addition, the sulfuric acid electric protection valve will be closed.

[0022] The present invention has the following beneficial effects:

[0023] The intelligent sulfuric acid dosing device and control method for circulating water described in this invention, during specific operation, uses online monitoring instruments installed on the circulating water makeup pipe to quickly and accurately determine the water quality of different water sources for the circulating cooling water. Simultaneously, combined with online instruments on the circulating water drain pipe and the circulating water makeup flow rate, the amount of sulfuric acid added to the circulating water is dynamically adjusted in advance. This allows for rapid and precise regulation of the circulating cooling water quality, ensuring that the pH and alkalinity are controlled to optimal values, guaranteeing the stability of the circulating cooling water quality. Dynamic adjustments are made based on level gauges installed on the cooling tower pool and a real-time water database of the circulating cooling water system. The system replenishes the circulating water supply, ensuring a stable liquid level in the cooling tower pool and effectively guaranteeing safe operation of the unit. It elevates the extensive operation and management of the circulating cooling water system to refined management and intelligent control, solving the problems of sampling and control lag in the circulating water system and addressing the risks of scaling and corrosion. It achieves the goals of prevention-oriented, safe and controllable, and water-saving priority in the circulating water system. Moreover, its high degree of automation and intelligence reduces the workload of operation and maintenance personnel and improves the safety, reliability, and economy of the circulating cooling water system. It is of great significance for ensuring safe operation of the unit and maximizing energy conservation and emission reduction. Attached Figure Description

[0024] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0025] Figure 1 This is a structural diagram of the present invention;

[0026] Figure 2 This is a schematic diagram of the method of the present invention.

[0027] Among them, 1 is a mechanical ventilation cooling tower, 2 is an intelligent wind speed, temperature and humidity measuring instrument, 3 is a cooling tower pool, 4 is a cooling tower pool level gauge, 5 is a sulfuric acid storage tank, 6 is the upper valve of the sulfuric acid storage tank level gauge, 7 is the lower valve of the sulfuric acid storage tank level gauge, 8 is the sulfuric acid storage tank level gauge, 9 is the sulfuric acid pipeline inlet valve, 10 is a filter, 11 is the booster pump inlet valve, 12 is the booster pump, 13 is the booster pump outlet valve, 14 is the booster pump bypass valve, 15 is the sulfuric acid regulating valve, 16 is the sulfuric acid regulating valve bypass valve, 17 is the sulfuric acid pipeline flow meter, 18 is the sulfuric acid electric protection valve, and 19 is the sulfuric acid... 20 is a pipeline check valve, 21 is a circulating water makeup water regulating valve, 22 is a circulating water makeup water regulating valve bypass valve, 23 is a circulating water makeup water flow meter, 24 is a circulating water makeup water sampling valve, 25 is a circulating water makeup water online pH meter, 26 is a circulating water makeup water online alkalinity meter, 27 is a circulating water drainage sampling valve, 28 is a circulating water drainage online pH meter, 29 is a circulating water drainage regulating valve, 30 is a circulating water drainage regulating valve bypass valve, 31 is a circulating water drainage flow meter, 32 is an industrial control computer and touch screen, and 33 is a PLC controller. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] In the description of this invention, it should be understood that the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0030] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0031] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Additionally, the character " / " in this invention generally indicates that the preceding and following objects have an "or" relationship.

[0032] It should be understood that although terms such as first, second, third, etc., may be used in the embodiments of the present invention to describe the preset range, these preset ranges should not be limited to these terms. These terms are only used to distinguish the preset ranges from one another. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0033] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0035] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0036] Example 1

[0037] refer to Figure 1The intelligent circulating water sulfuric acid dosing device of the present invention includes a mechanical ventilation cooling tower 1, an intelligent wind speed, temperature and humidity measuring instrument 2, a cooling tower pool 3, a cooling tower pool level gauge 4, a sulfuric acid storage tank 5, an upper valve of the sulfuric acid storage tank level gauge 6, a lower valve of the sulfuric acid storage tank level gauge 7, a sulfuric acid storage tank level gauge 8, a sulfuric acid pipeline inlet valve 9, a filter 10, a booster pump inlet valve 11, a booster pump 12, a booster pump outlet valve 13, a booster pump bypass valve 14, a sulfuric acid regulating valve 15, a sulfuric acid regulating valve bypass valve 16, a sulfuric acid pipeline flow meter 17, and a sulfuric acid electric protection valve 18. 19. Sulfuric acid pipeline check valve; 20. Circulating water makeup water regulating valve; 21. Circulating water makeup water regulating valve bypass valve; 22. Circulating water makeup water flow meter; 23. Circulating water makeup water sampling valve; 24. Circulating water makeup water online pH meter; 25. Circulating water makeup water online alkalinity meter; 26. Circulating water drainage sampling valve; 27. Circulating water drainage online pH meter; 28. Circulating water drainage online alkalinity meter; 29. ​​Circulating water drainage regulating valve; 30. Circulating water drainage regulating valve bypass valve; 31. Circulating water drainage flow meter; 32. Industrial control computer and touch screen; 33. PLC controller;

[0038] The outlet of sulfuric acid storage tank 5 is connected to cooling tower pool 3 via filter 10, booster pump inlet valve 11, booster pump 12, booster pump outlet valve 13, sulfuric acid regulating valve 15, sulfuric acid pipeline flow meter 17, sulfuric acid electric protection valve 18 and sulfuric acid pipeline check valve 19. Sulfuric acid regulating valve 15 is connected in parallel with sulfuric acid regulating valve bypass valve 16. The branch formed by booster pump inlet valve 11, booster pump 12 and booster pump outlet valve 13 is connected in parallel with booster pump bypass valve 14.

[0039] The circulating water makeup water pipeline is divided into two paths after passing through the circulating water makeup water regulating valve 20. One path is connected to the cooling tower pool 3 via the circulating water makeup water flow meter 22, and the other path is connected to the cooling tower pool 3 via the circulating water makeup water sampling valve 23. An online pH meter 24 and an online alkalinity meter 25 for circulating water makeup water are installed between the circulating water makeup water sampling valve 23 and the cooling tower pool 3. The online pH meter 24 and the online alkalinity meter 25 for circulating water makeup water are connected in parallel.

[0040] Sulfuric acid storage tank 5 is connected to sulfuric acid storage tank level gauge 8 via upper valve 6 and lower valve 7 of sulfuric acid storage tank level gauge.

[0041] A cooling tower pool level gauge 4 is installed inside the cooling tower pool 3.

[0042] The bottom outlet of the cooling tower pool 3 is connected to the circulating water drainage pipeline via a circulating water drainage regulating valve 29 and a circulating water drainage flow meter 31. The circulating water drainage regulating valve 29 is connected in parallel with a circulating water drainage regulating valve bypass valve 30. The bottom outlet of the cooling tower pool 3 is connected to the circulating water drainage pipeline via a circulating water drainage sampling valve 26, an online pH meter 27, and an online alkalinity meter 28. The online pH meter 27 and the online alkalinity meter 28 are connected in parallel.

[0043] The cooling tower pool 3 is located below the mechanical ventilation cooling tower 1, and the intelligent wind speed, temperature and humidity measuring instrument 2 is installed on the side of the mechanical ventilation cooling tower 1.

[0044] The PLC controller 33 is electrically connected to the circulating water makeup water regulating valve 20, circulating water makeup water flow meter 22, circulating water makeup water online pH meter 24, circulating water makeup water online alkalinity meter 25, intelligent wind speed, temperature and humidity measuring instrument 2, cooling tower pool level gauge 4, circulating water drainage online pH meter 27, circulating water drainage online alkalinity meter 28, circulating water drainage regulating valve 29, circulating water drainage flow meter 31, sulfuric acid storage tank level gauge 8, booster pump 12, sulfuric acid regulating valve 15, sulfuric acid pipeline flow meter 17, and sulfuric acid electric protection valve 18. The industrial control computer and touch screen 32 are communicatively connected to the PLC controller 33.

[0045] refer to Figure 2 The intelligent sulfuric acid dosing device control method for circulating water according to the present invention includes the following steps:

[0046] The pH setpoint of the circulating water in cooling tower pool 3 is subtracted from the value measured by the online pH meter 27 of the circulating water drainage as the error input of the pH-PID method. Then, the weight system K1 is used for proportional allocation to obtain the pH weight ratio parameter K11. The alkalinity setpoint of the circulating water in cooling tower pool 3 is subtracted from the value measured by the online alkalinity meter 28 of the circulating water drainage as the error input of the alkalinity-PID algorithm. Then, the weight system K2 is used for proportional allocation to obtain the alkalinity weight ratio parameter K12. The opening degree of the circulating water drainage regulating valve 29 is controlled according to the result of the cumulative processing of the pH weight ratio parameter K11 and the alkalinity weight ratio parameter K12 to regulate the circulating water drainage volume.

[0047] The result of subtracting the value measured by the cooling tower pool level gauge 4 from the set value of the cooling tower pool level 3 is used as the error input of the level-PID method; the intelligent wind speed and temperature humidity measuring instrument 2 retrieves the real-time water database of the circulating cooling water system to view the instantaneous loss DW; the opening degree of the circulating water replenishment regulating valve 20 is controlled according to the output result of the level-PID algorithm, the instantaneous loss DW and the cumulative result of the value measured by the circulating water drainage flow meter 31, so as to adjust the circulating water replenishment volume;

[0048] The pH difference is obtained by processing the values ​​measured by the online pH meter 27 of the circulating water drainage, the online pH meter 24 of the circulating water makeup water, and the pH setpoint of the circulating water in the cooling tower pool 3 through intelligent data processing and control unit. The alkalinity difference is obtained by processing the values ​​measured by the online alkalinity meter 25 of the circulating water makeup water, the online alkalinity meter 28 of the circulating water drainage, and the alkalinity setpoint of the circulating water in the cooling tower pool 3 through intelligent data processing and control unit. The pH difference and alkalinity difference are used as input signals to control the opening of the sulfuric acid regulating valve 15 through the automatic sulfuric acid addition control model to adjust the amount of sulfuric acid added to the circulating water.

[0049] When the value measured by the online pH meter 27 of the circulating water drainage is less than the pH setting value of the circulating water in the cooling tower pool 3, the value measured by the online alkalinity meter 28 of the circulating water drainage is less than the alkalinity setting value of the circulating water in the cooling tower pool 3, or the value measured by the sulfuric acid pipeline flow meter 17 is greater than the maximum allowable acid addition, the sulfuric acid electric protection valve 18 is controlled to close.

[0050] Example 2

[0051] refer to Figure 1 When putting the intelligent sulfuric acid dosing device into operation, close the bypass valve 21 of the circulating water makeup water regulating valve, the bypass valve 30 of the circulating water drainage regulating valve, the bypass valve 14 of the booster pump, and the bypass valve 16 of the sulfuric acid regulating valve. Open the sampling valve 23 of the circulating water makeup water, the sampling valve 26 of the circulating water drainage water, the upper valve 6 of the sulfuric acid storage tank level gauge, the lower valve 7 of the sulfuric acid storage tank level gauge, the inlet valve 9 of the sulfuric acid pipeline, the inlet valve 11 of the booster pump, and the outlet valve 13 of the booster pump. Set the pH setting value of the circulating water in the cooling tower pool 3, the liquid level setting value of the cooling tower pool 3, and the alkalinity setting value of the circulating water in the cooling tower pool 3 in the industrial control computer and touch screen 32. Click the automatic operation button to put the intelligent sulfuric acid dosing device into automatic operation.

[0052] like Figure 2 As shown, the result of subtracting the measured value of the circulating water drainage online pH meter 27 from the pH setpoint of the circulating water in the cooling tower pool 3 is used as the error input of the pH-PID method, and then the weight system K1 is used for proportional allocation to obtain the pH weight ratio parameter K11; the result of subtracting the measured value of the circulating water drainage online alkalinity meter 28 from the pH setpoint of the circulating water in the cooling tower pool 3 is used as the error input of the alkalinity-PID algorithm, and then the weight system K2 is used for proportional allocation to obtain the alkalinity weight ratio parameter K12; the opening degree of the circulating water drainage regulating valve 29 is controlled according to the sum of the pH weight ratio parameter K11 and the alkalinity weight ratio parameter K12 to regulate the circulating water drainage volume;

[0053] The result of subtracting the value measured by the cooling tower pool level gauge 4 from the set value of the cooling tower pool level 3 is used as the error input of the level-PID method; the intelligent wind speed, temperature and humidity measuring instrument 2 retrieves the real-time water database of the circulating cooling water system and checks the instantaneous loss DW; the opening degree of the circulating water replenishment regulating valve 20 is controlled according to the output result of the level-PID method, the instantaneous loss DW and the cumulative result of the value measured by the circulating water drainage flow meter 31, so as to adjust the circulating water replenishment volume;

[0054] The pH difference is obtained by processing the values ​​measured by the online pH meter 27 of the circulating water drainage, the online pH meter 24 of the circulating water makeup water, and the pH setpoint of the circulating water in the cooling tower pool 3 through the intelligent data processing and control unit. The alkalinity difference is obtained by processing the values ​​measured by the online alkalinity meter 25 of the circulating water makeup water, the online alkalinity meter 28 of the circulating water drainage, and the alkalinity setpoint of the circulating water in the cooling tower pool 3 through the intelligent data processing and control unit. The pH difference and alkalinity difference are used as input signals to control the opening of the sulfuric acid regulating valve 15 through the automatic sulfuric acid addition control model to adjust the amount of sulfuric acid added to the circulating water.

[0055] When the value measured by the online pH meter 27 of the circulating water drainage is less than the pH setting value of the circulating water in the cooling tower pool 3, the value measured by the online alkalinity meter 28 of the circulating water drainage is less than the alkalinity setting value of the circulating water in the cooling tower pool 3, or the value measured by the sulfuric acid pipeline flow meter 17 is greater than the maximum allowable acid addition, the sulfuric acid electric protection valve 18 is controlled to close.

[0056] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and disclosure of the invention. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the following claims.

[0057] It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

[0058] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Any simple modifications, alterations, or equivalent structural changes made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A control method for an intelligent sulfuric acid dosing device for circulating water, characterized in that, The intelligent circulating water sulfuric acid addition device includes a sulfuric acid storage tank (5), a cooling tower pool (3), a circulating water replenishment pipeline, a circulating water drainage pipeline, an intelligent wind speed and temperature humidity measuring instrument (2), and a mechanical ventilation cooling tower (1). The outlet of the sulfuric acid storage tank (5) is connected to the cooling tower pool (3), the circulating water makeup water pipe is connected to the cooling tower pool (3), a cooling tower pool level gauge (4) is installed in the cooling tower pool (3), the bottom outlet of the cooling tower pool (3) is connected to the circulating water drainage pipe, the cooling tower pool (3) is located below the mechanical ventilation cooling tower (1), and the intelligent wind speed, temperature and humidity measuring instrument (2) is installed on the side of the mechanical ventilation cooling tower (1); The outlet of the sulfuric acid storage tank (5) is connected to the cooling tower pool (3) via a filter (10), a booster pump inlet valve (11), a booster pump (12), a booster pump outlet valve (13), a sulfuric acid regulating valve (15), a sulfuric acid pipeline flow meter (17), a sulfuric acid electric protection valve (18), and a sulfuric acid pipeline check valve (19). The sulfuric acid regulating valve (15) is connected in parallel with a sulfuric acid regulating valve bypass valve (16); The branch formed by the booster pump inlet valve (11), the booster pump (12), and the booster pump outlet valve (13) is connected in parallel to the booster pump bypass valve (14); After passing through the circulating water makeup water regulating valve (20), the water is divided into two paths. One path is connected to the cooling tower pool (3) via the circulating water makeup water flow meter (22), and the other path is connected to the cooling tower pool (3) via the circulating water makeup water sampling valve (23). An online pH meter (24) and an online alkalinity meter (25) for circulating water makeup water are installed between the circulating water makeup water sampling valve (23) and the cooling tower pool (3). The online pH meter (24) and the online alkalinity meter (25) for circulating water makeup water are connected in parallel. It also includes a sulfuric acid storage tank level gauge (8), and the sulfuric acid storage tank (5) is connected to the sulfuric acid storage tank level gauge (8) through the upper valve (6) and the lower valve (7) of the sulfuric acid storage tank level gauge; The bottom outlet of the cooling tower pool (3) is connected to the circulating water drainage pipe via a circulating water drainage regulating valve (29) and a circulating water drainage flow meter (31). The circulating water drainage regulating valve (29) is connected in parallel with a circulating water drainage regulating valve bypass valve (30). The bottom outlet of the cooling tower pool (3) is connected to the circulating water drainage pipe via a circulating water drainage sampling valve (26), an online pH meter (27) for circulating water drainage, and an online alkalinity meter (28) for circulating water drainage. The online pH meter (27) for circulating water drainage and the online alkalinity meter (28) for circulating water drainage are connected in parallel. Includes the following steps: The result of subtracting the value measured by the online pH meter (27) of the circulating water in the cooling tower pool (3) from the pH setpoint of the circulating water is used as the error input of the pH-PID method. Then, the weight system K1 is used to perform proportional allocation to obtain the pH weight ratio parameter K11. The result of subtracting the value measured by the online alkalinity meter (28) of the circulating water in the cooling tower pool (3) from the alkalinity setpoint of the circulating water is used as the error input of the alkalinity-PID algorithm. Then, the weight system K2 is used to perform proportional allocation to obtain the alkalinity weight ratio parameter K12. The opening degree of the circulating water drainage regulating valve (29) is controlled according to the result of the cumulative processing of pH weight ratio parameter K11 and alkalinity weight ratio parameter K12 to regulate the circulating water drainage volume. The result of subtracting the value measured by the cooling tower pool level gauge (4) from the set value of the cooling tower pool level is used as the error input of the level-PID method; the intelligent wind speed and temperature humidity measuring instrument (2) retrieves the real-time water database of the circulating cooling water system to view the instantaneous loss DW; the opening of the circulating water replenishment water regulating valve (20) is controlled according to the output result of the level-PID algorithm, the instantaneous loss DW and the cumulative result of the value measured by the circulating water drainage flow meter (31) to adjust the amount of circulating water replenishment water; The pH difference is obtained by processing the values ​​measured by the online pH meter (27) of the circulating water drainage, the online pH meter (24) of the circulating water makeup water, and the pH setting value of the circulating water in the cooling tower pool (3) through intelligent data processing and control unit; the alkalinity difference is obtained by processing the values ​​measured by the online alkalinity meter (25) of the circulating water makeup water, the online alkalinity meter (28) of the circulating water drainage, and the alkalinity setting value of the circulating water in the cooling tower pool (3) through intelligent data processing and control unit; the pH difference is obtained by using the values ​​measured by the circulating water makeup water flow meter (22), the pH difference, and the alkalinity difference as input signals, and the opening of the sulfuric acid regulating valve (15) is controlled by the sulfuric acid addition automatic control model to adjust the amount of sulfuric acid added to the circulating water; When the value measured by the online pH meter (27) of the circulating water drainage is less than the pH setting value of the circulating water in the cooling tower pool (3), the value measured by the online alkalinity meter (28) of the circulating water drainage is less than the alkalinity setting value of the circulating water in the cooling tower pool (3), or the value measured by the sulfuric acid pipeline flow meter (17) is greater than the maximum allowable acid addition, the sulfuric acid electric protection valve (18) is controlled to close.

2. The control method for the intelligent sulfuric acid dosing device for circulating water according to claim 1, characterized in that, It also includes a PLC controller (33), which is electrically connected to the circulating water makeup water regulating valve (20), the circulating water makeup water flow meter (22), the circulating water makeup water online pH meter (24), the circulating water makeup water online alkalinity meter (25), the intelligent wind speed, temperature and humidity measuring instrument (2), the cooling tower pool level gauge (4), the circulating water drainage online pH meter (27), the circulating water drainage online alkalinity meter (28), the circulating water drainage regulating valve (29), the circulating water drainage flow meter (31), the sulfuric acid storage tank level gauge (8), the booster pump (12), the sulfuric acid regulating valve (15), the sulfuric acid pipeline flow meter (17), and the sulfuric acid electric protection valve (18).

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