An acid-base adjustment control system and a control method thereof

Abstract

The application provides an acid-base adjusting control system and a control method thereof. The acid-base adjusting control system is provided with a first dosing pump near a water inlet side, a second dosing pump near a water inlet end of a second adjusting tank, and the first dosing pump and the second dosing pump are independently connected to a storage tank; a first pH online monitoring device is arranged near a water outlet of a first adjusting tank, and a second pH online monitoring device is arranged near a water outlet end of the second adjusting tank; and a control unit is used for calculating and adjusting the dosing amount of the system according to the control strategy of the collected pH online monitoring value, water inflow value and other signals. Through the cooperation of each unit, the water inflow pH of the biochemical treatment unit, especially the anaerobic unit, is stabilized, the two-stage control of the acid-base adjusting process is realized, the water outflow pH is stabilized to reach the target range, the consumption of acid or alkali is saved, and the intelligent control level of the industrial wastewater treatment plant is improved.

Description

Technical Field

[0001] This invention belongs to the field of environmental protection research technology, and relates to an acid-base regulation and control system and its control method. Background Technology

[0002] Wastewater treatment is a typical nonlinear, multivariable, and strongly coupled system, characterized by high complexity and time-varying nature. Dynamic fluctuations in influent significantly impact the operational stability of the treatment process, leading to fluctuations in effluent quality. Industrial wastewater is affected by changes in upstream production cycles and processes, resulting in significant fluctuations in its volume, pollutant concentrations, and physical properties. Therefore, changes in the influent load of industrial wastewater treatment plants will impact the effectiveness of the treatment system, particularly the biological treatment unit. Influent pH is a crucial indicator for biological treatment processes; the optimal pH for microorganisms in widely used anaerobic and aerobic processes is approximately neutral.

[0003] Acid-base neutralization is a non-linear process, and its titration curve shows significant gain within the neutral range. Even small amounts of acid or alkali can cause large fluctuations in pH. Therefore, simply applying traditional control methods cannot meet the requirements for high control accuracy and stability. For example, Kang Yulong et al. used a feedforward + PI control method to regulate the pH of coking wastewater, dividing the control range into zones of 6.5-8.0, each corresponding to a different dosage. Fang Zhen'ao et al., for pH regulation of power plant wastewater, compared the effluent pH monitored online with the target value and calculated the required amount of acid or alkali using a formula. However, due to the complex and variable composition of industrial wastewater influent, and the inconsistent concentrations of neutralizing agents (often prepared from solid to liquid), using fixed curves or fixed calculation formulas for control can easily lead to deviations.

[0004] In summary, the biochemical processes in industrial wastewater treatment have high pH requirements, making effluent pH control during the pretreatment stage crucial. The acid-base reaction process is non-linear, exhibiting significant fluctuations in control precision and stability. Existing control methods also suffer from problems such as substantial control delays and dosage calculation errors due to the complex composition of raw water, thus affecting control effectiveness. Therefore, there is an urgent need to design an acid-base regulation and control system and its method to overcome the shortcomings of existing technologies and meet practical application needs. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an acid-base regulation control system and its control method. In this invention, through the coordinated arrangement of various units, the pH of the influent to the biochemical treatment unit, especially the anaerobic unit, is stabilized, ensuring precise control of the pH value of the effluent from the acid-base regulation unit. Furthermore, the acid-base regulation process is controlled in two stages, ensuring that the effluent pH stabilizes within the target range while effectively saving on the consumption of acid or alkali agents, reducing manual operation and maintenance costs, improving the intelligent control level of industrial wastewater treatment plants, and ensuring high safety.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides an acid-base adjustment and control system, comprising a first adjustment tank, a second adjustment tank, a first dosing pump, a second dosing pump, a first online pH monitoring device, a second online pH monitoring device, and a control unit; one end of the first adjustment tank is provided with an inlet, the inlet pipe being connected to raw water, and the other end of the first adjustment tank is provided with an outlet, the outlet pipe being connected to the inlet of the second adjustment tank, the outlet of the second adjustment tank being used for drainage by the acid-base adjustment and control system; the first dosing pump is provided near the inlet, the first dosing pump being used to add chemicals to the first adjustment tank, and the second dosing pump is provided near the inlet of the second adjustment tank, the second dosing pump being used to add chemicals to the second adjustment tank, the first dosing pump and the second dosing pump being independently connected to a chemical storage tank; the first online pH monitoring device is provided near the outlet, and the second online pH monitoring device is provided near the outlet of the second adjustment tank; the control unit is used to adjust the dosing amount of the acid-base adjustment and control system.

[0008] In this invention, the coordinated arrangement of each unit achieves stable influent pH in the biochemical treatment unit, especially the anaerobic unit, ensuring precise control of effluent pH in the acid-base adjustment unit. Furthermore, the acid-base adjustment process is controlled in two stages, ensuring that the effluent pH remains stable within the target range while effectively saving on acid or alkali reagent consumption, reducing manual operation and maintenance costs, improving the intelligent control level of the industrial wastewater treatment plant, and ensuring high safety.

[0009] It should be noted that the present invention does not impose any special limitations on the specific model, shape, material, or other features of the first and second dosing pumps, and those skilled in the art can make adaptive adjustments according to the actual situation.

[0010] As a preferred technical solution of the present invention, a total inlet flow meter is provided at the inlet of the raw water.

[0011] Preferably, a first electromagnetic flow meter is installed at the outlet end of the first dosing pump.

[0012] Preferably, a second electromagnetic flow meter is provided at the outlet end of the second dosing pump.

[0013] It should be noted that the present invention does not impose any special limitations on the specific models, shapes, and materials of the total inlet flow meter, the first electromagnetic flow meter, and the second electromagnetic flow meter, and those skilled in the art can make adaptive adjustments according to the actual situation.

[0014] As a preferred technical solution of the present invention, the first pH online monitoring device is a first pH online monitoring instrument.

[0015] Preferably, the second pH online monitoring device is a second pH online monitoring instrument.

[0016] It should be noted that the present invention does not impose any special limitations on the specific model, shape, material, or other features of the first and second online pH monitoring instruments, and those skilled in the art can make adaptive adjustments according to the actual situation.

[0017] Preferably, a first stirrer is provided in the first regulating tank.

[0018] Preferably, a second stirrer is provided in the second regulating tank.

[0019] It should be noted that the present invention does not impose any special limitations on the specific model, shape, material, or other features of the first and second stirrers. Those skilled in the art can make adaptive adjustments according to the actual situation. The first and second stirrers may be the same or different.

[0020] As a preferred embodiment of the present invention, the control unit includes an acquisition module, a calculation module, a control module, and a transmission module.

[0021] The data acquisition module is used to collect data from various types of flow meters and pH online monitoring instruments, and transmit the data to the calculation module for calculation via a wired or wireless network.

[0022] The sampling period of the acquisition module is 5 to 60 seconds, for example, it can be 5 seconds, 10 seconds, 20 seconds, 30 seconds, 40 seconds, 50 seconds, 60 seconds, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0023] The computing module outputs data via a wired or wireless network and feeds it back to the control module in real time.

[0024] The control module is electrically connected to the first dosing pump and the second dosing pump respectively, and is used to control the dosing amount of the first dosing pump and the dosing amount of the second dosing pump.

[0025] The transmission module is used to upload data to the cloud, so that operators can remotely view and control system operations.

[0026] In a second aspect, the present invention provides a control method for the acid-base regulation control system described in the first aspect, the control method comprising:

[0027] By controlling the first and second dosing pumps through the control unit, and combining the data from the first and second online pH monitoring devices, the dosing amount in the first and second equalization tanks is adjusted in real time, respectively.

[0028] The pH value of the effluent from the first equalization tank, the pH value of the effluent from the second equalization tank, and the influent flow rate were detected and collected.

[0029] Under continuous water intake conditions, the dosage of the first dosing pump and the dosage of the second dosing pump are calculated by controlling the pH values ​​of the first online monitoring device and the second online monitoring device within specific ranges of rise and fall.

[0030] Under continuous water intake conditions, in response to sudden pH changes, the monitoring data from the online pH monitoring device is used to identify the issue based on the control strategy, and the dosage of the first and second dosing pumps is calculated and adjusted accordingly.

[0031] Under continuous water intake conditions, the dosage of the first dosing pump and the dosage of the second dosing pump are calculated and adjusted according to the phased changes in pH value, and the start and stop of the first dosing pump and the second dosing pump are controlled respectively.

[0032] Under intermittent water intake conditions, the start and stop of the first and second dosing pumps are controlled based on the online monitoring value of the total water intake flow meter.

[0033] As a preferred embodiment of the present invention, the target pH values ​​for the first and second equalization tanks are set as pH... t1 pH t2 When the influent acidity is adjusted to alkaline or neutral, the maximum pH control values ​​for the first and second equalization tanks are set to pH values ​​of [value missing]. m1 and pH m2 When the influent alkalinity is adjusted to acidity or neutrality, the minimum pH control values ​​for the first and second equalization tanks are set to pH values ​​respectively. n1 and pH n2 .

[0034] When the acid-base adjustment and control system is operating with continuous water intake and the pH is adjusted from acidic to alkaline or neutral, Q1 is calculated based on the pH value of the first online pH monitoring device. The calculation method is as follows:

[0035]

[0036] When pH t1 ≤pH1(t)<pH m1 When that happens, the output Q1(t) = Q 1min ;

[0037] When pH1(t) ≥ pH m1 If the condition continues for n1 minutes, then the output Q1(t) = 0, 1 ≤ n1 ≤ 10;

[0038] When pH1(t) < pH t1 If the condition persists for m1 minutes, then the output Q1(t) is calculated according to the above strategy, where 1≤m1≤10.

[0039] When the acid-base adjustment and control system is operating with continuous water intake and the pH is adjusted from alkaline to acidic or neutral, Q1 is calculated based on the pH value of the first online pH monitoring device. The calculation method is as follows:

[0040]

[0041] When pH n1 ≤pH1(t)<pH t1 When that happens, the output Q1(t) = Q 1min ;

[0042] When pH1(t) ≤ pH n1 If the condition continues for n1 minutes, then the output Q1(t) = 0, 1 ≤ n1 ≤ 10;

[0043] When pH1(t) > pH t1 If the condition persists for m1 minutes, then the output Q1(t) is calculated according to the above strategy, where 1≤m1≤10.

[0044] Where Q1(t) is the dosage of the first regulating tank calculated at the current time, Q1 is the output dosage of the first regulating tank, and Q... 1min To set the minimum dosage for the first dosing pump, pH t1 The target value for the dosage in the first equalization tank is given by pH1(t), where pH1(t) is the pH value monitored in the first equalization tank at the current moment. m1 The maximum pH value set for the first equalization tank, pH n1 The minimum pH value set for the first equalization tank;

[0045] K p1 K is the first proportionality coefficient, and its value ranges from 100 to 8000. I1 K is the first integral coefficient, and its value ranges from 1000 to 80000. D1 is the first differential coefficient, and its value ranges from 0.1 to 1.0.

[0046] When the acid-base adjustment and control system is operating with continuous water intake and the pH is adjusted from acidic to alkaline or neutral, Q2 is calculated based on the pH value of the second online pH monitoring device. The calculation method is as follows:

[0047]

[0048] When pH t2 ≤pH2(t)<pH m2 When that happens, the output is Q2(t) = Q. 2min ;

[0049] When pH2(t) ≥ pH m2 If the condition continues for n2 minutes, then the output Q2(t) = 0, 1 ≤ n2 ≤ 10;

[0050] When pH2(t) < pH m2 If the duration is m2 minutes, then the output Q2(t) is calculated according to the above strategy, where 1≤m2≤10.

[0051] When the acid-base adjustment control system is operating with continuous water intake and the pH is adjusted from alkaline to acidic or neutral, Q2 is calculated based on the pH value of the second online pH monitoring device. The calculation method is as follows:

[0052]

[0053] When pH n2 ≤pH2(t)<pH t2 When that happens, the output is Q2(t) = Q. 2min ;

[0054] When pH2(t) ≤ pH n2 If the condition continues for n2 minutes, then the output Q2(t) = 0, 1 ≤ n2 ≤ 10;

[0055] When pH2(t) > pH n2 If the duration is m2 minutes, then the output Q2(t) is calculated according to the above strategy, where 1≤m2≤10.

[0056] Where Q2(t) is the dosage of the second regulating tank calculated at the current time, Q2 is the output dosage of the second regulating tank, and Q... 2min To set the minimum dosage for the second dosing pump, pH t2 The target value for the dosage in the second equalization tank is given by pH2(t), where pH2(t) is the pH value monitored in the second equalization tank at the current moment. m2 The maximum pH value set for the second equalization tank, pH n2 The minimum pH value set for the second equalization tank;

[0057] K p2The second proportionality coefficient, K, ranges from 1000 to 300000. I2 K is the second integral coefficient, and its value ranges from 10000 to 500000. D2 The second differential coefficient has a value range of 0.1 to 1.0.

[0058] As a preferred technical solution of the present invention, within a specific range of pH value increase monitored by the second pH online monitoring device, the dosage of the second equalization tank is adjusted, and the adjustment is carried out in the following manner:

[0059] When α×pH t2 <pH2(t)<pH t2 At that time, Q2 = Q2(t) × (1 ± a);

[0060] Under conditions where the pH is adjusted from alkaline to acidic or neutral, Q2 = Q2(t) × (1 + a);

[0061] Under conditions where the pH is adjusted from acidic to alkaline or neutral, Q2 = Q2(t) × (1-a);

[0062] Where α is the rising interval coefficient, with a value range of 0.50 to 0.99, and a is the rising interval adjustment coefficient, with a value range of 0.05 to 0.5.

[0063] As a preferred embodiment of the present invention, when the acid-base adjustment control system is operating under continuous water intake, the dosage of the second adjustment tank is adjusted within a specific range of pH value decrease monitored by the second online pH monitoring device. The adjustment method is as follows:

[0064] When pH t2 <pH2(t)<β×pH t2 At that time, Q2 = Q2(t) × (1 ± b);

[0065] Under conditions where the pH is adjusted from alkaline to acidic or neutral, Q2 = Q2(t) × (1-b);

[0066] Under conditions where the pH is adjusted from acidic to alkaline or neutral, Q2 = Q2(t) × (1 + b);

[0067] Where β is the decreasing interval coefficient, with a value range of 0.01 to 0.2, and b is the decreasing interval adjustment coefficient, with a value range of 0.1 to 1.

[0068] As a preferred technical solution of the present invention, when the acid-base adjustment control system is operating under continuous water intake, it automatically identifies sudden jumps or drops in pH value caused by drastic fluctuations in the raw water, and adjusts the dosage of the first adjustment tank and the dosage of the second adjustment tank respectively. The adjustment method is as follows:

[0069] When dpH1(t) / dt > γ1 for n consecutive times, Q1 = Q 1min ;

[0070] Wherein, γ1 is the first jump coefficient, and its value ranges from 0.08 to 0.3, and n ranges from 5 to 24;

[0071] When dpH2(t) / dt > γ2 for n consecutive times, Q2 = Q 2min ;

[0072] Wherein, γ2 is the second jump coefficient, which ranges from 0.05 to 0.2, and n ranges from 5 to 24;

[0073] Where pH1(t) is the pH value monitored in the first equalization tank at the current moment, and Q 1min Q1 represents the minimum dosage of the first dosing pump, Q2(t) represents the output dosage to the first equalization tank, and pH2(t) represents the pH value monitored in the second equalization tank at the current moment. 2min Q1 is the minimum dosage of the second dosing pump, and Q2 is the output dosage of the second equalization tank.

[0074] As a preferred embodiment of the present invention, when the acid-base adjustment and control system operates in intermittent water intake mode, the start / stop status of the dosing in the first and second adjustment tanks is adjusted according to the monitored flow rate of the total influent flow meter. The adjustment method is as follows:

[0075] When the inflow rate Q inf =0, when the duration is t, then output Q1 = 0 after delay t1 and output Q2 = 0 after delay t2;

[0076] Where 0 ≤ t1 ≤ 30 min, t1 ≤ t2 < 60 min, and 0 < t ≤ 5 min;

[0077] When the inflow rate Q inf When pH > 0 and the duration is t, the system starts and calculates Q1 and Q2 respectively according to the current pH1(t) and pH2(t) using the strategy.

[0078] Where 0 < t ≤ 5 min.

[0079] It should be noted that in this invention, "calculating Q1 and Q2 according to the strategy" refers to satisfying the influent flow rate Q. inf When the pH value is greater than 0 and the duration is t, the repeated operation is performed within the range of pH increase or decrease monitored by the second pH online monitoring device. The method of adjusting the dosage and the calculation method for the phased changes in pH value caused by changes in the production cycle / process are used to achieve reasonable adjustment of the dosage.

[0080] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0081] In this invention, by coordinating the various units and controlling the acid-base adjustment process in two stages, the problem of unstable pH control caused by the complex composition of wastewater and the nonlinearity of the acid-base neutralization curve is avoided. This ensures that the effluent pH reaches the target range while effectively saving the consumption of acid or alkali agents, reducing manual operation and maintenance costs, and contributing to the stable operation of subsequent biochemical units, especially anaerobic units. This improves the intelligent control level of industrial wastewater treatment plants and ensures high safety. Attached Figure Description

[0082] Figure 1 A schematic diagram of an acid-base regulation and control system provided in a specific embodiment of the present invention;

[0083] Figure 2 A schematic diagram of a control method for an acid-base regulation control system provided in a specific embodiment of the present invention;

[0084] Among them, 1-first equalization tank; 2-second equalization tank; 3-first dosing pump; 4-second dosing pump; 5-drug storage tank; 6-acquisition module; 7-calculation module; 8-control module; 9-transmission module; 10-first stirrer; 11-second stirrer. Detailed Implementation

[0085] It should be understood that in the description of this invention, the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0086] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0087] Those skilled in the art should understand that the present invention necessarily includes the necessary pipelines, conventional valves and general pump equipment for achieving complete process, but the above content is not the main inventive point of the present invention. Those skilled in the art can add layouts based on process flow and equipment structure selection, and the present invention does not make any special requirements or specific limitations in this regard.

[0088] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0089] In one specific embodiment, the present invention provides an acid-base regulation and control system, such as... Figure 1 As shown, the acid-base adjustment and control system includes a first adjustment tank 1, a second adjustment tank 2, a first dosing pump 3, a second dosing pump 4, a first online pH monitoring device, a second online pH monitoring device, and a control unit. One end of the first adjustment tank 1 has an inlet connected to raw water, and the other end has an outlet connected to the inlet of the second adjustment tank 2. The outlet of the second adjustment tank 2 is used for drainage by the acid-base adjustment and control system. The first dosing pump 3 is located near the inlet and is used to add chemicals to the first adjustment tank 1. The second dosing pump 4 is located near the inlet of the second adjustment tank 2 and is used to add chemicals to the second adjustment tank 2. The first and second dosing pumps 3 and 4 are independently connected to a chemical storage tank 5. The first online pH monitoring device is located near the outlet, and the second online pH monitoring device is located near the outlet of the second adjustment tank 2. The control unit is used to adjust the dosage of chemicals in the acid-base adjustment and control system.

[0090] It should be noted that the present invention does not impose any special limitations on the specific model, shape, material, or other features of the first dosing pump 3 and the second dosing pump 4, and those skilled in the art can make adaptive adjustments according to the actual situation.

[0091] Furthermore, a total inlet flow meter is installed at the raw water inlet, a first electromagnetic flow meter is installed at the outlet of the first dosing pump 3, and a second electromagnetic flow meter is installed at the outlet of the second dosing pump 4. It should be noted that this invention does not impose specific limitations on the model, shape, and material of the total inlet flow meter, the first electromagnetic flow meter, and the second electromagnetic flow meter; those skilled in the art can make adaptive adjustments according to actual conditions.

[0092] Furthermore, the first pH online monitoring device is a first pH online monitoring instrument, and the second pH online monitoring device is a second pH online monitoring instrument. It should be noted that the present invention does not impose specific limitations on the model, shape, material, or other features of the first and second pH online monitoring instruments; those skilled in the art can make adaptive adjustments according to actual circumstances.

[0093] Furthermore, a first stirrer 10 is provided in the first regulating tank 1, and a second stirrer 11 is provided in the second regulating tank 2. It should be noted that the present invention does not impose special limitations on the specific model, shape, material, and other features of the first stirrer 10 and the second stirrer 11. Those skilled in the art can make adaptive adjustments according to the actual situation. The first stirrer 10 and the second stirrer 11 can be the same or different.

[0094] Furthermore, the control unit includes a data acquisition module 6, a calculation module 7, a control module 8, and a transmission module 9. The data acquisition module 6 is used to acquire data from various types of flow meters and pH online monitoring instruments, and transmits the data to the calculation module 7 for calculation via a wired or wireless network. The sampling period of the data acquisition module 6 is 5–60 seconds. The calculation module 7 outputs data via a wired or wireless network and feeds it back to the control module 8 in real time. The control module 8 is electrically connected to the first dosing pump 3 and the second dosing pump 4, respectively, and is used to control the dosing amount of the first dosing pump 3 and the second dosing pump 4. The transmission module 9 is used to upload the data to the cloud, so that operators can remotely view and control the system operation.

[0095] In another specific embodiment, the present invention provides a control method for the above-described acid-base regulation control system, such as... Figure 2 As shown, the control method includes:

[0096] By controlling the first dosing pump 3 and the second dosing pump 4 through the control unit, and combining the data from the first pH online monitoring device and the second pH online monitoring device, the dosing amount of the first equalization tank 1 and the dosing amount of the second equalization tank 2 are adjusted in real time respectively.

[0097] The pH value of the effluent from the first equalization tank 1, the pH value of the effluent from the second equalization tank 2, and the influent flow rate were detected and collected.

[0098] Under continuous water intake conditions, the dosage of the first dosing pump 3 and the dosage of the second dosing pump 4 are calculated by controlling the pH values ​​of the first online monitoring device and the second online monitoring device within specific ranges of rise and fall.

[0099] Under continuous water intake conditions, in response to sudden pH changes, the monitoring data from the pH online monitoring device is used to identify the issue based on the control strategy, and the dosage of the first dosing pump 3 and the dosing amount of the second dosing pump 4 are calculated and adjusted accordingly.

[0100] Under continuous water intake conditions, the dosage of the first dosing pump 3 and the dosage of the second dosing pump 4 are calculated and adjusted according to the phased changes in pH value, and the start and stop of the first dosing pump 3 and the second dosing pump 4 are controlled respectively.

[0101] Under intermittent water intake conditions, the start and stop of the first dosing pump 3 and the second dosing pump 4 are controlled according to the online monitoring value of the total water intake flow meter.

[0102] Furthermore, the target pH values ​​for the first equalization tank 1 and the second equalization tank 2 are set as pH... t1 pH t2 When the influent acidity is adjusted to alkalinity, the maximum pH control values ​​for the first equalization tank 1 and the second equalization tank 2 are set to pH values ​​respectively. m1 and pH m2 When the influent alkalinity is adjusted to acidity, the minimum pH control values ​​for the first equalization tank 1 and the second equalization tank 2 are set to pH values ​​respectively. n1 and pH n2 .

[0103] Furthermore, when the acid-base adjustment control system operates with continuous water intake and the pH is adjusted from acidic to alkaline or neutral, Q1 is calculated based on the pH value of the first online pH monitoring device, using the following calculation method:

[0104]

[0105] When pH t1 ≤pH1(t)<pH m1 When that happens, the output Q1(t) = Q 1min ;

[0106] When pH1(t) ≥ pH m1 If the value continues for n1 minutes, the output Q1(t) = 0, 1 ≤ n1 ≤ 10. For example, it can be 1, 3, 5, 9, 10, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0107] When pH1(t) < pH t1If the value continues for m1 minutes, the output Q1(t) is calculated according to the above strategy, where 1≤m1≤10. For example, it can be 1, 3, 5, 9, 10, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0108] Furthermore, when the acid-base adjustment control system operates with continuous water intake and the pH is adjusted from alkaline to acidic or neutral, Q1 is calculated based on the pH value of the first online pH monitoring device, using the following calculation method:

[0109]

[0110] When pH n1 ≤pH1(t)<pH t1 When that happens, the output Q1(t) = Q 1min ;

[0111] When pH1(t) ≤ pH n1 If the value continues for n1 minutes, the output Q1(t) = 0, 1 ≤ n1 ≤ 10. For example, it can be 1, 3, 5, 9, 10, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0112] When pH1(t) > pH t1 If the value continues for m1 minutes, the output Q1(t) is calculated according to the above strategy, where 1≤m1≤10. For example, it can be 1, 3, 5, 9, 10, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0113] Where Q1(t) is the dosage of the first regulating tank 1 calculated at the current time, Q1 is the output dosage of the first regulating tank 1, and Q 1min To set the minimum dosage for the first dosing pump 3, pH t1 The target value for the dosage of chemicals in the first equalization tank 1 is defined as pH1(t), where pH1(t) is the pH value monitored in the first equalization tank 1 at the current moment. m1 The maximum pH value set for the first equalization tank 1, pH n1 The minimum pH value set for the first equalization tank 1;

[0114] K p1 This is the first proportionality coefficient, and its value ranges from 100 to 8000. For example, it can be 100, 1000, 5000, 8000, etc., but it is not limited to the listed values. Other unlisted values ​​within this range also apply; K I1is the first integral coefficient, and its value ranges from 1000 to 80000. For example, it can be 1000, 10000, 30000, 50000, 80000, etc., but it is not limited to the listed values. Other unlisted values ​​within this range also apply; K D1 The first differential coefficient has a value range of 0.1 to 1.0, such as 0.1, 0.5, 0.8, 1, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0115] Furthermore, when the acid-base adjustment control system operates with continuous water intake and the pH is adjusted from acidic to alkaline or neutral, Q2 is calculated based on the pH value of the second online pH monitoring device. The calculation method is as follows:

[0116]

[0117] When pH t2 ≤pH2(t)<pH m2 When that happens, the output is Q2(t) = Q. 2min ;

[0118] When pH2(t) ≥ pH m2 If the value continues for n2 minutes, the output Q2(t) = 0, 1 ≤ n2 ≤ 10. For example, it can be 1, 3, 5, 9, 10, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0119] When pH2(t) < pH m2 If the value continues for m2 minutes, the output Q2(t) is calculated according to the above strategy, where 1≤m2≤10. For example, it can be 1, 3, 5, 9, 10, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0120] Furthermore, when the acid-base adjustment control system operates with continuous water intake and the pH is adjusted from alkaline to acidic or neutral, Q2 is calculated based on the pH value of the second online pH monitoring device. The calculation method is as follows:

[0121]

[0122] When pH n2 ≤pH2(t)<pH t2 When that happens, the output is Q2(t) = Q. 2min ;

[0123] When pH2(t) ≤ pH n2If the value continues for n2 minutes, the output Q2(t) = 0, 1 ≤ n2 ≤ 10. For example, it can be 1, 3, 5, 9, 10, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0124] When pH2(t) > pH n2 If the value continues for m2 minutes, the output Q2(t) is calculated according to the above strategy, where 1≤m2≤10. For example, it can be 1, 3, 5, 9, 10, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0125] Where Q2(t) is the dosage of the second regulating tank 2 calculated at the current time, Q2 is the output dosage of the second regulating tank 2, and Q 2min To set the minimum dosage for the second dosing pump 4, pH t2 The target value for the dosage of chemicals in the second equalization tank 2 is defined as pH2(t), where pH2(t) is the pH value monitored in the second equalization tank 2 at the current moment. m2 The maximum pH value set for the second equalization tank 2, pH n2 The minimum pH value set for the second equalization tank 2;

[0126] K p2 This is the second proportionality coefficient, and its value ranges from 1000 to 300000. For example, it can be 1000, 100000, 200000, 300000, etc., but it is not limited to the listed values. Other unlisted values ​​within this range also apply; K I2 is the second integral coefficient, and its value ranges from 10,000 to 500,000. For example, it can be 10,000, 100,000, 200,000, 300,000, 400,000, 500,000, etc., but it is not limited to the listed values; other unlisted values ​​within this range also apply. K D2 This is the second differential coefficient, and its value ranges from 0.1 to 1.0. For example, it can be 0.1, 0.5, 0.8, 1, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0127] Furthermore, within a specific range of pH increase monitored by the second online pH monitoring device, the dosage in the second equalization tank 2 is adjusted as follows:

[0128] When α×pH t2 <pH2(t)<pH t2 At that time, Q2 = Q2(t) × (1 ± a);

[0129] Under conditions where the pH is adjusted from alkaline to acidic or neutral, Q2 = Q2(t) × (1 + a);

[0130] Under conditions where the pH is adjusted from acidic to alkaline or neutral, Q2 = Q2(t) × (1-a);

[0131] Wherein, α is the rising interval coefficient, and its value ranges from 0.50 to 0.99. For example, it can be 0.5, 0.8, 0.9, 0.99, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable. a is the rising interval adjustment coefficient, and its value ranges from 0.05 to 0.5. For example, it can be 0.05, 0.1, 0.3, 0.5, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0132] Furthermore, when the acid-base adjustment control system is operating with continuous water intake, within a specific range of pH value decrease monitored by the second online pH monitoring device, the dosage of chemicals in the second equalization tank 2 is adjusted in the following manner:

[0133] When pH t2 <pH2(t)<β×pH t2 At that time, Q2 = Q2(t) × (1 ± b);

[0134] Under conditions where the pH is adjusted from alkaline to acidic or neutral, Q2 = Q2(t) × (1-b);

[0135] Under conditions where the pH is adjusted from acidic to alkaline or neutral, Q2 = Q2(t) × (1 + b);

[0136] Wherein, β is the descending interval coefficient, and its value ranges from 0.01 to 0.2. For example, it can be 0.01, 0.05, 0.1, 0.2, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable. b is the descending interval adjustment coefficient, and its value ranges from 0.1 to 1. For example, it can be 0.1, 0.5, 0.8, 1, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0137] Furthermore, when the acid-base adjustment control system is operating with continuous water intake, it automatically identifies sudden spikes or drops in pH value caused by drastic fluctuations in the raw water, and adjusts the dosage of chemicals in the first equalization tank 1 and the second equalization tank 2 respectively. The adjustment method is as follows:

[0138] When dpH1(t) / dt > γ1 for n consecutive times, Q1 = Q 1min ;

[0139] Wherein, γ1 is the first jump coefficient, and its value ranges from 0.08 to 0.3. n ranges from 5 to 24, for example, it can be 5, 10, 15, 20, 24, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0140] When dpH2(t) / dt > γ2 for n consecutive times, Q2 = Q 2min ;

[0141] Wherein, γ2 is the second jump coefficient, which ranges from 0.05 to 0.2, and n ranges from 5 to 24. For example, it can be 5, 10, 15, 20, 24, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0142] Where pH1(t) is the pH value monitored in the first equalization tank 1 at the current moment, and Q 1min Q1 represents the minimum dosage of the first dosing pump 3, Q1 represents the output dosage of the first equalization tank 1, and pH2(t) represents the pH value monitored in the second equalization tank 2 at the current moment. 2min Q1 is the minimum dosage of the second dosing pump 4, and Q2 is the output dosage of the second regulating tank 2.

[0143] Furthermore, when the acid-base regulation and control system is operating in intermittent water intake mode, the start / stop status of the dosing in the first regulation tank 1 and the second regulation tank 2 is adjusted according to the monitored flow rate of the total influent flow meter. The adjustment method is as follows:

[0144] When the inflow rate Q inf =0, when the duration is t, then output Q1 = 0 after delay t1 and output Q2 = 0 after delay t2;

[0145] Where 0 ≤ t1 ≤ 30 min, for example, it can be 0 min, 10 min, 20 min, 30 min, etc., but is not limited to the listed values, and other unlisted values ​​within this range also apply; t1 ≤ t2 < 60 min, for example, it can be 59 min, 50 min, 40 min, etc., but is not limited to the listed values, and other unlisted values ​​within this range also apply; 0 < t ≤ 5 min, for example, it can be 0.5 min, 1 min, 3 min, 5 min, etc., but is not limited to the listed values, and other unlisted values ​​within this range also apply.

[0146] When the inflow rate Q inf When pH > 0 and the duration is t, the system starts and calculates Q1 and Q2 respectively according to the current pH1(t) and pH2(t) using the strategy.

[0147] Where 0 < t ≤ 5 min, for example, it can be 0.5 min, 1 min, 3 min, 5 min, etc., but it is not limited to the listed values. Other unlisted values ​​within this range also apply.

[0148] It should be noted that in this invention, "calculating Q1 and Q2 according to the strategy" refers to satisfying the influent flow rate Q. inf When the pH value is greater than 0 and the duration is t, the repeated operation is performed within the range of pH increase or decrease monitored by the second pH online monitoring device. The method of adjusting the dosage and the calculation method for the phased changes in pH value caused by changes in the production cycle / process are used to achieve reasonable adjustment of the dosage.

[0149] Example 1

[0150] This embodiment provides a control method for an acid-base adjustment control system, wherein:

[0151] A liquor wastewater treatment plant has a daily treatment capacity of 4000 m³. 3 The pH of the raw wastewater varies from 4.0 to 6.5 throughout the year. Two equalization tanks are used in the pretreatment stage to regulate the influent pH, with the target pH being [value missing]. t1 =5.0, pH t2 =7.2.

[0152] One online pH meter (1#pH) is installed at the end of the outlet channel of the first equalization tank 1, and one online pH meter (2#pH) is installed at the end of the outlet channel of the second equalization tank 2. The pH measurement interval is 5 seconds. Sodium hydroxide solution is delivered to the front end of the first equalization tank 1 by the first dosing pump 3 via pipeline, and to the front end of the second equalization tank 2 by the second dosing pump 4 via pipeline. The dosing rate of the dosing pumps is set to Q. min =50L / h, Q max =270L / h.

[0153] (1) When the acid-base adjustment control system is running with continuous water intake and the pH is adjusted from acidic to alkaline, Q1 is calculated based on the pH value of the first online pH monitoring device. The calculation method is as follows:

[0154]

[0155] When pH t1 ≤pH1(t)<pH m1 When that happens, the output Q1(t) = Q 1min ;

[0156] When pH1(t) ≥ pH m1 If the condition continues for n1 minutes, then the output Q1(t) = 0, 1 ≤ n1 ≤ 10;

[0157] When pH1(t) < pH t1 If the duration is m1 minutes, then the output Q1(t) is calculated according to the above strategy, where 1≤m1≤10;

[0158] K p1 For 5000, K I1 For 50000, K D1 The value is 0.3; n1 is 5, and m1 is 5.

[0159] (2) When the acid-base adjustment control system is operating with continuous water intake and the pH is adjusted from acidic to alkaline, Q2 is calculated based on the pH value of the second online pH monitoring device. The calculation method is as follows:

[0160]

[0161] When pH t2 ≤pH2(t)<pH m2 When that happens, the output is Q2(t) = Q. 2min ;

[0162] When pH2(t) ≥ pH m2 If the condition continues for n2 minutes, then the output Q2(t) = 0, 1 ≤ n2 ≤ 10;

[0163] When pH2(t) < pH m2 If the duration is m2 minutes, then the output Q2(t) is calculated according to the above strategy, where 1≤m2≤10;

[0164] K p2 For 150,000, K I2 For 100000, K D2 =0.2; n2 = 2, m2 = 2.

[0165] (3) Within the specific range of pH increase monitored by the second pH online monitoring device, adjust the dosage of the second equalization tank 2. The adjustment method is as follows:

[0166] When α×pH t2 <pH2(t)<pH t2 At that time, Q2 = Q2(t) × (1-a);

[0167] Where α is 0.59 and a is 0.25.

[0168] (4) Within a specific range of pH decrease monitored by the second online pH monitoring device, adjust the dosage of the second equalization tank 2. The adjustment method is as follows:

[0169] When pH t2 <pH2(t)<β×pH t2At that time, Q2 = Q2(t) × (1 + b);

[0170] Where β is 0.12 and b is 0.5.

[0171] (5) When the acid-base adjustment control system is operating with continuous water intake, it automatically identifies sudden jumps or drops in pH value caused by drastic fluctuations in the raw water and adjusts the dosage of the first equalization tank 1 and the second equalization tank 2 respectively. The adjustment method is as follows:

[0172] When dpH1(t) / dt > γ1 for n consecutive times, Q1 = Q 1min ;

[0173] Where γ1 is 0.1 and n is 10;

[0174] When dpH2(t) / dt > γ2 for n consecutive times, Q2 = Q 2min ;

[0175] Where γ2 is 0.15 and n is 8.

[0176] (6) When the acid-base regulation and control system is operating in intermittent water intake mode, the start / stop status of the dosing in the first regulation tank 1 and the second regulation tank 2 shall be adjusted according to the monitored flow rate of the total influent flow meter. The adjustment method shall be as follows:

[0177] When the inflow rate Q inf =0, when the duration is t, then output Q1 = 0 after delay t1 and output Q2 = 0 after delay t2;

[0178] Where t1 is 2 min; t2 is 10 min; t is 1 min;

[0179] When the inflow rate Q inf When pH > 0 and the duration is t, the system starts and calculates Q1 and Q2 respectively according to the current pH1(t) and pH2(t) using the strategy.

[0180] Where t is 5 minutes.

[0181] The plant used the system and method of this invention for pH control, achieving an effluent pH of 7.20 ± 0.27, with a variation range of 6.98 to 7.50, saving 28.6% of the dosage.

[0182] Example 2

[0183] This embodiment provides a control method for an acid-base regulation control system, wherein the differences from Embodiment 1 are as follows, while other parameters and experimental conditions are the same as in Embodiment 1;

[0184] The control objective of this embodiment is pH. t1=5.0, pH t2 =7.0.

[0185] (1) When the acid-base adjustment and control system is operating with continuous water intake and the pH is adjusted from acidic to neutral, Q1 is calculated based on the pH value of the first online pH monitoring device. The calculation method is as follows:

[0186]

[0187] When pH n1 ≤pH1(t)<pH t1 When that happens, the output Q1(t) = Q 1min ;

[0188] When pH1(t) ≤ pH n1 If the condition continues for n1 minutes, then the output Q1(t) = 0, 1 ≤ n1 ≤ 10;

[0189] When pH1(t) > pH t1 If the duration is m1 minutes, then the output Q1(t) is calculated according to the above strategy, where 1≤m1≤10;

[0190] K p1 For 2000, K I1 For 25000, K D1 It is 0.5.

[0191] (2) When the acid-base adjustment and control system is operating with continuous water intake and the pH is adjusted from acidic to neutral, Q2 is calculated based on the pH value of the second online pH monitoring device. The calculation method is as follows:

[0192]

[0193] When pH n2 ≤pH2(t)<pH t2 When that happens, the output is Q2(t) = Q. 2min ;

[0194] When pH2(t) ≤ pH n2 If the condition continues for n2 minutes, then the output Q2(t) = 0, 1 ≤ n2 ≤ 10;

[0195] When pH2(t) > pH n2 If the duration is m2 minutes, then the output Q2(t) is calculated according to the above strategy, where 1≤m2≤10;

[0196] K p2 For 200000, K I2 For 200000, K D2 It is 0.1.

[0197] (3) Within the specific range of pH increase monitored by the second pH online monitoring device, adjust the dosage of the second equalization tank 2. The adjustment method is as follows:

[0198] When α×pH t2 <pH2(t)<pH t2 At that time, Q2 = Q2(t) × (1-a);

[0199] Where α is 0.6 and a is 0.3.

[0200] (4) Within a specific range of pH decrease monitored by the second online pH monitoring device, adjust the dosage of the second equalization tank 2. The adjustment method is as follows:

[0201] When pH t2 <pH2(t)<β×pH t2 At that time, Q2 = Q2(t) × (1 + b);

[0202] Where β is 0.15 and b is 0.25.

[0203] (5) When the acid-base adjustment control system is operating with continuous water intake, it automatically identifies sudden jumps or drops in pH value caused by drastic fluctuations in the raw water and adjusts the dosage of the first equalization tank 1 and the second equalization tank 2 respectively. The adjustment method is as follows:

[0204] When dpH1(t) / dt > γ1 for n consecutive times, Q1 = Q 1min ;

[0205] Where γ1 is 0.2 and n is 15;

[0206] When dpH2(t) / dt > γ2 for n consecutive times, Q2 = Q 2min ;

[0207] Where γ2 is 0.1 and n is 10.

[0208] (6) When the acid-base regulation and control system is operating in intermittent water intake mode, the start / stop status of the dosing in the first regulation tank 1 and the second regulation tank 2 shall be adjusted according to the monitored flow rate of the total influent flow meter. The adjustment method shall be as follows:

[0209] When the inflow rate Q inf =0, when the duration is t, then output Q1 = 0 after delay t1 and output Q2 = 0 after delay t2;

[0210] Where t1 is 5 min; t2 is 12 min; t is 3 min;

[0211] When the inflow rate Q infWhen pH > 0 and the duration is t, the system starts and calculates Q1 and Q2 respectively according to the current pH1(t) and pH2(t) using the strategy.

[0212] Where t is 3 minutes.

[0213] The plant used the system and method of this invention for pH control, achieving an effluent pH of 7.00 ± 0.18, with a variation range of 6.85 to 7.46, saving 21.40% of the dosage.

[0214] In summary, this invention achieves stable influent pH in the biochemical treatment unit, especially the anaerobic unit, through the coordinated arrangement of various units, ensuring precise control of the effluent pH value of the acid-base adjustment unit. Furthermore, the acid-base adjustment process is controlled in two stages, ensuring that the effluent pH stabilizes within the target range while effectively saving on acid or alkali reagent consumption, reducing manual operation and maintenance costs, improving the intelligent control level of industrial wastewater treatment plants, and ensuring high safety.

[0215] The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A control method for an acid-base regulation control system, characterized in that, The control method includes: The control method employs an acid-base adjustment and control system comprising a first adjustment tank, a second adjustment tank, a first dosing pump, a second dosing pump, a first online pH monitoring device, a second online pH monitoring device, and a control unit; The first regulating tank has an inlet at one end, and the inlet pipe is connected to the raw water. The other end of the first regulating tank has an outlet, and the outlet pipe is connected to the inlet of the second regulating tank. The outlet of the second regulating tank is used for drainage by the acid-base regulating control system. A first dosing pump is provided near the inlet side, and the first dosing pump is used to add chemicals to the first equalization tank. A second dosing pump is provided near the inlet side of the second equalization tank, and the second dosing pump is used to add chemicals to the second equalization tank. The first dosing pump and the second dosing pump are independently connected to the chemical storage tank. The first pH online monitoring device is located near the outlet, and the second pH online monitoring device is located near the outlet of the second equalization tank; The control unit is used to adjust the dosage of the acid-base regulation control system; By controlling the first and second dosing pumps through the control unit, and combining the data from the first and second online pH monitoring devices, the dosing amount in the first and second equalization tanks is adjusted in real time, respectively. The pH value of the effluent from the first equalization tank, the pH value of the effluent from the second equalization tank, and the influent flow rate were detected and collected. Under continuous water intake conditions, the dosage of the first dosing pump and the dosage of the second dosing pump are calculated by controlling the pH values ​​of the first online monitoring device and the second online monitoring device within specific ranges of rise and fall. Under continuous water intake conditions, in response to sudden pH changes, the monitoring data from the online pH monitoring device is used to identify the issue based on the control strategy, and the dosage of the first and second dosing pumps is calculated and adjusted accordingly. Under continuous water intake conditions, the dosage of the first dosing pump and the dosage of the second dosing pump are calculated and adjusted according to the phased changes in pH value, and the start and stop of the first dosing pump and the second dosing pump are controlled respectively. Under intermittent water intake conditions, the start and stop of the first and second dosing pumps are controlled based on the online monitoring value of the total water intake flow meter; The target pH values ​​for the first and second equalization tanks are set as pH. t1 pH t2 ; When the influent acidity is adjusted to alkaline or neutral, the maximum pH control values ​​for the first and second equalization tanks are set to pH values ​​respectively. m1 and pH m2 When the influent alkalinity is adjusted to acidity or neutrality, the minimum pH control values ​​for the first and second equalization tanks are set to pH values ​​respectively. n1 and pH n2 ; When the acid-base adjustment and control system is operating with continuous water intake and the pH is adjusted from acidic to alkaline or neutral, Q1 is calculated based on the pH value of the first online pH monitoring device. The calculation method is as follows: ; When pH t1 ≤pH1(t)<pH m1 When the time is right, the output Q1(t) = Q 1min ; When pH1(t) ≥ pH m1 If the condition continues for n1 minutes, then the output Q1(t) = 0, 1 ≤ n1 ≤ 10; When pH1(t) < pH t1 If the duration is m1 minutes, then calculate the output Q1(t) according to the above strategy, where 1≤m1≤10; When the acid-base adjustment and control system is operating with continuous water intake and the pH is adjusted from alkaline to acidic or neutral, Q1 is calculated based on the pH value of the first online pH monitoring device. The calculation method is as follows: ； When pH n1 ≤pH1(t)<pH t1 When the time is right, the output Q1(t) = Q 1min ; When pH1(t) ≤ pH n1 If the condition continues for n1 minutes, then the output Q1(t) = 0, 1 ≤ n1 ≤ 10; When pH1(t) > pH t1 If the duration is m1 minutes, then calculate the output Q1(t) according to the above strategy, where 1≤m1≤10; Where Q1(t) is the dosage of the first regulating tank calculated at the current time, Q1 is the output dosage of the first regulating tank, and Q 1min To set the minimum dosage for the first dosing pump, pH t1 The target value for the dosage in the first equalization tank is given by pH1(t), where pH1(t) is the pH value monitored in the first equalization tank at the current moment. m1 The maximum pH value set for the first equalization tank, pH n1 The minimum pH value set for the first equalization tank; K p1 K is the first proportionality coefficient, with a value ranging from 100 to 8000. I1 K is the first integral coefficient, and its value ranges from 1000 to 80000. D1 This is the first differential coefficient, and its value ranges from 0.1 to 1.0; When the acid-base adjustment and control system is operating with continuous water intake and the pH is adjusted from acidic to alkaline or neutral, Q2 is calculated based on the pH value of the second online pH monitoring device. The calculation method is as follows: ； When pH t2 ≤pH2(t)<pH m2 When the time is right, the output Q2(t) = Q 2min ; When pH2(t) ≥ pH m2 If the condition continues for n2 minutes, then the output Q2(t) = 0, 1 ≤ n2 ≤ 10; When pH2(t) < pH m2 If the duration is m2 minutes, then the output Q2(t) is calculated according to the above strategy, where 1≤m2≤10; When the acid-base adjustment control system is operating with continuous water intake and the pH is adjusted from alkaline to acidic or neutral, Q2 is calculated based on the pH value of the second online pH monitoring device. The calculation method is as follows: ； When pH n2 ≤pH2(t)<pH t2 When the time is right, the output Q2(t) = Q 2min ; When pH2(t) ≤ pH n2 If the condition continues for n2 minutes, then the output Q2(t) = 0, 1 ≤ n2 ≤ 10; When pH2(t) > pH n2 If the duration is m2 minutes, then the output Q2(t) is calculated according to the above strategy, where 1≤m2≤10; Where Q2(t) is the dosage of the second regulating tank calculated at the current time, Q2 is the output dosage of the second regulating tank, and Q... 2min To set the minimum dosage for the second dosing pump, pH t2 The target value for the dosage in the second equalization tank is given by pH2(t), which is the pH value monitored in the second equalization tank at the current moment. m2 The maximum pH value set for the second equalization tank, pH n2 The minimum pH value set for the second equalization tank; K p2 The second proportionality coefficient, K, has a value ranging from 1000 to 300000. I2 K is the second integral coefficient, and its value ranges from 10000 to 500000. D2 This is the second differential coefficient, and its value ranges from 0.1 to 1.0; Within a specific range of pH increase monitored by the second online pH monitoring device, adjust the dosage in the second equalization tank as follows: When α×pH t2 <pH2(t)<pH t2 At that time, Q2 = Q2(t) × (1 ± a); Under conditions where the alkaline environment is adjusted to acidic or neutral, Q2 = Q2(t) × (1 + a); Under conditions where the pH is adjusted from acidic to alkaline or neutral, Q2 = Q2(t) × (1-a); Where α is the rising interval coefficient, with a value range of 0.50 to 0.99, and a is the rising interval adjustment coefficient, with a value range of 0.05 to 0.

5.

2. The control method according to claim 1, characterized in that, A total inlet flow meter is installed at the inlet of the raw water; The first electromagnetic flow meter is installed at the outlet end of the first dosing pump; A second electromagnetic flow meter is installed at the outlet end of the second dosing pump.

3. The control method according to claim 1, characterized in that, The first pH online monitoring device is a first pH online monitoring instrument; The second pH online monitoring device is a second pH online monitoring instrument; The first regulating tank is equipped with a first stirrer; A second stirrer is installed in the second regulating tank.

4. The control method according to claim 1, characterized in that, The control unit includes a data acquisition module, a calculation module, a control module, and a transmission module; The data acquisition module is used to collect data from various types of flow meters and pH online monitoring instruments, and transmit the data to the calculation module for calculation via a wired or wireless network. The sampling period of the acquisition module is 5~60s; The computing module outputs data through a wired or wireless network and feeds it back to the control module in real time; The control module is electrically connected to the first dosing pump and the second dosing pump respectively, and is used to control the dosing amount of the first dosing pump and the dosing amount of the second dosing pump; The transmission module is used to upload data to the cloud, so that operators can remotely view and control system operations.

5. The control method according to claim 1, characterized in that, When the acid-base adjustment and control system is operating with continuous water intake, within a specific range of pH value decrease monitored by the second online pH monitoring device, the dosage of the second adjustment tank is adjusted in the following manner: When pH t2 <pH2(t) <β×pH t2 At that time, Q2 = Q2(t) × (1 ± b); Under conditions where the pH is adjusted from alkaline to acidic or neutral, Q2 = Q2(t) × (1-b); Under conditions where the pH is adjusted from acidic to alkaline or neutral, Q2 = Q2(t) × (1 + b); Where β is the decreasing interval coefficient, with a value range of 0.01 to 0.2, and b is the decreasing interval adjustment coefficient, with a value range of 0.1 to 1.

6. The control method according to claim 5, characterized in that, When the acid-base adjustment and control system is operating with continuous water intake, it automatically identifies sudden jumps or drops in pH value caused by drastic fluctuations in the raw water, and adjusts the dosage of chemicals in the first and second adjustment tanks respectively. The adjustment method is as follows: When dpH1(t) / dt > γ1 for n consecutive times, Q1 = Q 1min ; Wherein, γ1 is the first jump coefficient, with a value range of 0.08 to 0.3, and n has a value range of 5 to 24; When dpH2(t) / dt > γ2 for n consecutive times, Q2 = Q 2min ; Wherein, γ2 is the second jump coefficient, with a value range of 0.05 to 0.2, and n has a value range of 5 to 24; Where pH1(t) is the pH value monitored in the first equalization tank at the current moment, and Q 1min Q1 represents the minimum dosage of the first dosing pump, Q2(t) represents the output dosage to the first equalization tank, and pH2(t) represents the pH value monitored in the second equalization tank at the current moment. 2min Q1 is the minimum dosage of the second dosing pump, and Q2 is the output dosage of the second equalization tank.

7. The control method according to claim 6, characterized in that, When the acid-base regulation and control system is operating in intermittent water intake mode, the start / stop status of the dosing in the first and second regulating tanks is adjusted according to the monitored flow rate of the total influent flow meter. The adjustment method is as follows: When the inflow rate Q inf =0, when the duration is t, then after delay t1, output Q1=0, and after delay t2, output Q2=0; Where 0 ≤ t1 ≤ 30 min, t1 ≤ t2 < 60 min, and 0 < t ≤ 5 min; When the inflow rate Q inf When pH > 0 and the duration is t, the system starts and calculates Q1 and Q2 respectively according to the current pH1(t) and pH2(t) using the strategy. Where 0 < t ≤ 5 min.

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