High-salinity wastewater multi-stage oxidation treatment system and optimized operation method

Abstract

The invention discloses a multi-stage oxidation treatment system for high-salinity wastewater and an optimized operation method, and relates to the technical field of high-salinity wastewater, the method comprises the following steps: collecting oxidation parameters of each stage of reaction tank through an integrated sensor and a processor; setting a target degradation efficiency, a maximum oxidant adding threshold value and a byproduct concentration threshold value based on the initial water quality; adjusting the adding amount of each stage of oxidizing agent through a sliding mode-PID composite controller; setting a dynamic oxidant parameter regulation strategy, and dynamically adjusting the oxidant mixing speed and reaction time according to the real-time temperature and pH value; if the by-product concentration of any stage is greater than 1.2 times of the by-product concentration threshold value, or the accumulated medicament cost exceeds the set medicament cost threshold value, updating the target degradation efficiency, the maximum oxidant adding threshold value and the by-product concentration threshold value, and triggering an alarm. The problems that in the multi-stage oxidation process, the adding amount of each stage of oxidizing agent is difficult to accurately control, the optimal degradation effect is achieved, and meanwhile the agent cost is reduced are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of high-salt wastewater, and specifically to a multi-stage oxidation treatment system and an optimized operation method for high-salt wastewater. Background Art

[0002] As an advanced chemical treatment method, the multi-stage oxidation treatment technology can achieve the complete oxidation and mineralization of high-concentration organic pollutants by allowing the wastewater to enter multiple oxidation reaction stages in sequence and making full use of the decomposition effects of each stage of oxidation reaction on different types of organic matter. However, the complexity of the reaction system in a high-salt environment, such as the influence of salts on the oxidation reaction kinetics and the generation of by-products, requires precise control and dynamic optimization of the multi-stage oxidation system to achieve safe, economical, and efficient operation.

[0003] In recent years, with the gradual application of the Internet of Things (IoT), automation control technology, and machine learning methods in environmental protection engineering, in the multi-stage oxidation process, how to precisely control the dosage of oxidants at each stage to achieve the best degradation effect while reducing the chemical cost has become an urgent problem to be solved. Moreover, excessive dosing may lead to the accumulation of by-products and increase the burden of secondary treatment, while insufficient dosing may not achieve the degradation target.

[0004] Therefore, the present invention provides a multi-stage oxidation treatment system and an optimized operation method for high-salt wastewater. Summary of the Invention

[0005] The purpose of the present invention is to provide a multi-stage oxidation treatment system and an optimized operation method for high-salt wastewater to solve the existing problems mentioned in the above background art.

[0006] To achieve the above purpose, the present invention provides the following technical solutions: A multi-stage oxidation treatment system and an optimized operation method for high-salt wastewater, including the following steps:

[0007] S1. Collect the oxidation parameters of each reaction tank through an integrated sensor and a processor;

[0008] S2. Set the target degradation efficiency, the maximum oxidant dosing threshold, and the by-product concentration threshold based on the initial water quality;

[0009] S3. Adjust the oxidant dosing amount at each stage through a sliding mode-PID composite controller;

[0010] S4. Set a dynamic oxidant parameter regulation strategy, and dynamically adjust the oxidant mixing speed and reaction time according to the real-time temperature and pH value;

[0011] S5. If the concentration of by-products at any level is greater than 1.2 times the threshold value of by-product concentration, or the cumulative chemical cost exceeds the set chemical cost threshold, return to S2, update the target degradation efficiency, the maximum oxidant dosage threshold, and the by-product concentration threshold, and trigger an alarm.

[0012] A further improvement of the present invention lies in that the sliding mode-PID composite controller specifically includes:

[0013] S31. Taking the by-product concentration as a constraint, the difference between the by-product concentration and the preset by-product concentration threshold is used as the sliding mode surface;

[0014] S32. The equivalent control rate is used to maintain the system state on the sliding mode surface. The equivalent control rate of oxidant dosage and the switching control rate of oxidant dosage are calculated by multiplying the sliding mode surface by the equivalent controller gain. The total control rate is obtained by adding the equivalent control rate and the oxygen switching control rate.

[0015] S33. When the increase value of the by-product concentration within the rated time T exceeds the set by-product increase threshold, directly cut off the current oxidant dosage and activate the standby process. Otherwise, proceed to S34;

[0016] S34. Adjust the oxidant dosage of each level through the switching control law until the sliding mode surface is less than 0.

[0017] A further improvement of the present invention lies in that the sliding mode-PID composite controller further includes: comparing the actual degradation efficiency with the target efficiency to generate an error signal; directly adjusting the oxidant dosage according to the error magnitude; accumulating historical errors to predict the future error trend to obtain the PID output. Obtain the comprehensive oxidant dosage regulation signal. Where is the reference dosage, and α and β represent weights.

[0018] A further improvement of the present invention lies in that the dynamic oxidant parameter regulation strategy inputs the temperature, pH value, and oxidant concentration data into the central controller, which is updated every 5 seconds to form a dynamic parameter matrix; through the temperature dynamic speed regulation strategy, calculate the first mixing speed v tem = v base ×(1 - k tem ·(T - T opt ))), calculate the second mixing speed v pH = v base ×(1 + k pH ·(pH - pH opt ))), k tem and k pHRepresents the sliding mode controller gain, and combines the coupling temperature dynamic speed regulation strategy and the pH value dynamic speed regulation strategy to obtain a mixed speed adjustment value:

[0019] v mix =v base ×(δ1(1 + k pH ·(pH - pH opt )) + δ2(1 + k tem ·(T - T opt )));

[0020] Wherein, T opt represents the standard temperature, pH opt represents the standard pH value, δ1 and δ2 represent weights, v base represents the set reference reaction speed. The controller calculates the mixed speed adjustment value according to the real-time data and outputs an instruction to the variable frequency stirrer.

[0021] A further improvement of the present invention lies in that the reaction time is dynamically regulated according to the real-time temperature and pH value. After constructing a temperature-reaction rate model according to the Arrhenius equation and then correcting the pH oxidation efficiency, the corrected reaction time is obtained:

[0022]

[0023] Wherein, t base represents the set reference reaction time, R represents the gas constant, and Ea represents the reaction activation energy.

[0024] A further improvement of the present invention lies in that the oxidation parameters of each stage of the reaction tank include organic matter concentration, oxidant concentration, by-product concentration, temperature and pH value; based on the historical operation data, a mathematical model between the wastewater quality and the oxidation reaction efficiency is constructed based on the SVM model, and the oxidation dose required to achieve the target degradation effect under specific initial conditions is obtained, and a safe maximum dosing threshold is set. At the same time, the maximum value of the by-product concentration generated during the reaction process is extracted as the by-product concentration threshold; through experiments, the reaction conditions and oxidation dose required to achieve a 90% COD removal rate under the current water quality are determined to obtain the target degradation efficiency.

[0025] A further improvement of the present invention lies in that the update rules for the target degradation efficiency, the maximum oxidant dosing threshold and the by-product concentration threshold include modifying the target conditions of the target degradation efficiency to the reaction conditions and oxidation dose required to achieve a 92% COD removal rate.

[0026] On the other hand, the present invention provides a multi-stage oxidation treatment system and an optimized operation system for high-salt wastewater, including:

[0027] A data acquisition module, which collects the oxidation parameters of each stage of the reaction tank by integrating sensors and processors;

[0028] A data setting module that sets a target degradation efficiency, a maximum oxidant dosage threshold, and a by-product concentration threshold based on the initial water quality;

[0029] A sliding mode-PID composite controller construction module that adjusts the oxidant dosage at each level through a sliding mode-PID composite controller;

[0030] A dynamic oxidant parameter regulation strategy module that dynamically adjusts the oxidant mixing speed and reaction time according to the real-time temperature and pH value;

[0031] A data update module that, if the concentration of by-products at any level is greater than 1.2 times the by-product concentration threshold, or the cumulative chemical agent cost exceeds the set chemical agent cost threshold, returns to S2, updates the target degradation efficiency, the maximum oxidant dosage threshold, and the by-product concentration threshold, and triggers an alarm.

[0032] Compared with the prior art, the beneficial effects of the present invention are:

[0033] 1. First, through the sliding mode and PID composite control algorithm, the present invention can dynamically adjust the oxidant dosage according to real-time feedback data, which not only prevents the generation of by-products due to excessive dosage but also ensures efficient degradation under water quality fluctuations;

[0034] 2. By using the control algorithm, unnecessary oxidant dosage is reduced, the usage amount of chemical agents is decreased, thereby saving the cost of chemical reagents; at the same time, the optimized regulation of the mixing speed and reaction time effectively reduces energy consumption. Description of the Drawings

[0035] Figure 1 It is a flow chart of a multi-stage oxidation treatment system and an optimized operation method for high-salt wastewater of the present invention;

[0036] Figure 2 It is a flow chart of a sliding mode-PID composite controller of a multi-stage oxidation treatment system and an optimized operation method for high-salt wastewater of the present invention;

[0037] Figure 3 It is a system framework diagram of a multi-stage oxidation treatment system and an optimized operation system for high-salt wastewater of the present invention. Detailed Embodiments

[0038] The technical solution of the present invention will be described in detail below through the drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations on the technical solution of the present invention. Without conflict, the technical features in the embodiments of the present invention and the embodiments can be combined with each other.

[0039] The term "and / or" is merely a description of the relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. Additionally, the character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0040] Example 1

[0041] Figure 1 The figure shows a flowchart of a multi-stage oxidation treatment system and an optimized operation method for high-salt wastewater disclosed in this example. The steps are as follows:

[0042] S1. By integrating sensors and a processor, including an organic matter concentration sensor, an oxidant concentration sensor, a by-product sensor, a pH sensor, and a temperature sensor, collect the oxidation parameters of each reaction tank; the oxidation parameters of each reaction tank include the organic matter concentration the oxidant concentration the by-product concentration the temperature T and the pH value

[0043] S2. Set the target degradation efficiency η target 、the maximum oxidant dosage threshold Q max and the by-product concentration threshold C byprod,th ;

[0044] Based on historical operation data, construct a mathematical model between the wastewater quality and the oxidation reaction efficiency using the SVM model. Obtain the amount of oxidant required to achieve the target degradation effect under specific initial conditions, and set a safe maximum dosage threshold. At the same time, extract the maximum value of the by-product concentration generated during the reaction as the by-product concentration threshold; determine the reaction conditions and the amount of oxidant required to achieve a 90% COD removal rate under the current water quality through experiments to obtain the target degradation efficiency.

[0045] S3. Adjust the oxidant dosage of each stage through a sliding mode-PID composite controller.

[0046] Example 2

[0047] Figure 2 The figure shows a flowchart of the sliding mode-PID composite controller for a multi-stage oxidation treatment system and an optimized operation method of the present invention. Based on the inventive concept of Example 1, adjust the oxidant dosage of each stage through a sliding mode-PID composite controller. The specific steps include;

[0048] S31. Taking the by-product concentration as a constraint, use the difference between the by-product concentration and the preset by-product concentration threshold as the sliding surface;

[0049] S32. Use the equivalent control rate to maintain the system state on the sliding surface, define the sliding surface

[0050]

[0051] Calculate the equivalent control rate and the switching control rate of oxidant dosing by multiplying the sliding mode surface and the equivalent controller gain. The equivalent control rate is expressed as The switching control rate is expressed as The total control rate is obtained by adding the equivalent control rate and the switching control rate

[0052] S33. When the increase value of the by-product concentration exceeds the set by-product increase threshold within the rated time T, directly cut off the current oxidant dosing and activate the standby process; otherwise, proceed to S34;

[0053] S34. Adjust the oxidant dosing amount at each level through the switching control law Until the sliding mode surface is less than 0. The sliding mode - PID composite controller further includes: comparing the actual degradation efficiency with the target efficiency to generate an error signal; the actual degradation efficiency Directly adjust the oxidant dosing amount according to the magnitude of the error. The error amount is expressed as Accumulate the historical error to predict the future error trend to obtain the proportional term (P): directly adjust the oxidant dosing amount according to the magnitude of the error. The greater the error, the greater the increase in the dosing amount; the integral term (I): accumulate the historical error to solve the long-term deviation; the derivative term (D): predict the future error trend to prevent overshoot (such as reducing the dosing amount in advance when the degradation efficiency increases rapidly); obtain the PID output Obtain the comprehensive oxidant dosing amount regulation signal Wherein is the reference dosing amount, and α and β represent weights.

[0054] Adopt the sliding mode - PID composite control strategy to dynamically regulate the oxidant dosing. The system is based on the error between the actual degradation effect (such as COD removal rate) and the target value. Through the three operations of proportional, integral, and derivative, the system dynamically adjusts the oxidant dosing amount, which can not only quickly respond to instantaneous deviations but also gradually correct long-term deviations, ensuring a steady improvement in the degradation effect.

[0055] The combination of the two control strategies enables the oxidant dosing neither to produce by-products due to excessive dosing nor to affect the degradation effect due to insufficient dosing, ensuring the stable and efficient operation of the system. And it can adapt to water quality fluctuations, quickly respond to emergencies (such as a sudden increase in by-products or a decrease in COD removal rate), ensuring the safe and stable operation of the system. By finely regulating the dosing amount, it effectively reduces the waste of oxidants, saves operating costs, and at the same time avoids the secondary treatment costs caused by excessive by-products

[0056] S4. Set a dynamic oxidant parameter regulation strategy to dynamically adjust the oxidant mixing speed and reaction time according to the real-time temperature and pH value;

[0057] The dynamic oxidant parameter regulation strategy forms a dynamic parameter matrix by inputting temperature, pH value, and oxidant concentration data into the central controller, which is updated every 5 seconds. High-temperature scenario: An increase in temperature will accelerate the decomposition of the oxidant, and the mixing speed needs to be reduced. Low-temperature scenario: Increase the mixing speed to enhance the mass transfer efficiency and compensate for the insufficient reaction rate. Through the temperature dynamic speed regulation strategy, calculate the first mixing speed v tem = v base ×(1 - k tem ·(T - T opt ))), and calculate the second mixing speed v pH = v base ×(1 + k pH ·(pH - pH opt ))), where k tem and k pH represent the sliding mode controller gains. Coupling the temperature dynamic speed regulation strategy and the pH value dynamic speed regulation strategy to obtain the adjusted value of the mixing speed:

[0058] v mix = v base ×(δ1(1 + k pH ·(pH - pH opt )) + δ2(1 + k tem ·(T - T opt )));

[0059] Among them, T opt represents the standard temperature, pH opt represents the standard pH value, δ1 and δ2 represent weights, and v base represents the set reference reaction speed. The controller calculates the adjusted value of the mixing speed based on the real-time data and outputs an instruction to the variable frequency stirrer.

[0060] The reaction time is dynamically regulated according to the real-time temperature and pH value. According to the Arrhenius equation, an increase in temperature will accelerate the reaction rate and the reaction time can be shortened. Therefore, after constructing a temperature-reaction rate model and then correcting the pH oxidation efficiency, the corrected reaction time is obtained:

[0061]

[0062] Among them, t base represents the set reference reaction time, R represents the gas constant, and Ea represents the reaction activation energy.

[0063] S5. If the concentration of by-products at any level is greater than 1.2 times the threshold value of by-product concentration, or the cumulative chemical cost exceeds the set chemical cost threshold, return to S2, update the target degradation efficiency, the maximum oxidant dosage threshold, and the by-product concentration threshold, and trigger an alarm.

[0064] The update rules for the target degradation efficiency, the maximum oxidant dosage threshold, and the by-product concentration threshold include modifying the target conditions of the target degradation efficiency to the reaction conditions and oxidant dosage required to achieve a COD removal rate of 92%.

[0065] Example 3

[0066] Figure 3 It shows a framework diagram of a multi-stage oxidation treatment system and an optimized operation system for high-salt wastewater of the present invention. Based on the same inventive concept as Example 1, the present invention provides a multi-stage oxidation treatment system and an optimized operation system for high-salt wastewater, including:

[0067] A data acquisition module, which collects oxidation parameters of each reaction tank by integrating sensors and processors;

[0068] A data setting module, which sets the target degradation efficiency, the maximum oxidant dosage threshold, and the by-product concentration threshold based on the initial water quality;

[0069] A sliding mode-PID composite controller construction module, which adjusts the oxidant dosage of each level through a sliding mode-PID composite controller;

[0070] A dynamic oxidant parameter regulation strategy module, which dynamically adjusts the oxidant mixing speed and reaction time according to the real-time temperature and pH value;

[0071] A data update module. If the concentration of by-products at any level is greater than 1.2 times the threshold value of by-product concentration, or the cumulative chemical cost exceeds the set chemical cost threshold, return to S2, update the target degradation efficiency, the maximum oxidant dosage threshold, and the by-product concentration threshold, and trigger an alarm.

[0072] Those skilled in the art should understand that the embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0073] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing device generate a means for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or one or more of the blocks.

[0074] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including an instruction means that implements the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or one or more of the blocks.

[0075] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or one or more of the blocks.

[0076] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the spirit and scope protected by the present invention and the claims. All of these are within the protection scope of the present invention.

Claims

1. A high-salinity wastewater multi-stage oxidation treatment system and an optimized operation method, characterized in that: The following steps are involved: S1. Collect oxidation parameters of each level of reaction pool through integrated sensors and processors; S2. Setting target degradation efficiency, maximum oxidant addition threshold and byproduct concentration threshold based on initial water quality; S3, adjusting the dosage of oxidant at each level through the sliding mode-PID composite controller; S4. Setting a dynamic oxidant parameter control strategy to dynamically adjust the oxidant mixing speed and reaction time according to the real-time temperature and pH value; S5. If the byproduct concentration of any level is greater than 1.2 times the byproduct concentration threshold, or the cumulative reagent cost exceeds the set reagent cost threshold, return to S2, update the target degradation efficiency, maximum oxidant addition threshold and byproduct concentration threshold, and trigger an alarm.

2. A high-salinity wastewater multi-stage oxidation treatment system and optimized operation method according to claim 1, characterized in that: The sliding mode-PID composite controller specifically includes: S31, taking the by-product concentration as a constraint, and taking the difference between the by-product concentration and a preset by-product concentration threshold as a sliding surface; S32, using the equivalent control rate to maintain the system state on the sliding surface, calculating the oxidant addition equivalent control rate and the oxidant addition switching control rate by multiplying the sliding surface and the equivalent controller gain, and obtaining the total control rate by adding the equivalent control rate and the oxygen switching control rate S33, when the by-product concentration rises by more than the set by-product rise threshold within the rated time T, the current oxidant addition is directly cut off and the standby process is activated, otherwise, S34 is performed; S34. Adjust the dosage of oxidant at each level by switching the control law until the sliding surface is less than 0.

3. A high-salinity wastewater multi-stage oxidation treatment system and optimized operation method according to claim 2, characterized in that: The sliding mode-PID composite controller also includes: comparing the actual degradation efficiency with the target efficiency to generate an error signal; directly adjusting the oxidant dosage according to the error size; accumulating historical errors to predict future error trends to obtain a PID output Obtain comprehensive oxidant dosage control signal in is the reference dosage, α and β represent the weights.

4. A high-salinity wastewater multi-stage oxidation treatment system and optimized operation method according to claim 1, characterized in that: The dynamic oxidant parameter control strategy forms a dynamic parameter matrix by inputting temperature, pH value and oxidant concentration data into a central controller and updating it every 5 seconds; the first mixing speed v is calculated by the temperature dynamic speed control strategy. tem =v base ×(1-k tem ·(TT opt )) Calculate the second mixing speed v by pH value dynamic speed regulation strategy pH =v base ×(1+k pH ·(pH-pH opt )), k tem and k pH Represents the sliding mode controller gain, and the temperature dynamic speed regulation strategy and pH value dynamic speed regulation strategy are coupled to obtain the mixed speed adjustment value: v mix =v base ×(δ1(1+k pH ·(pH-pH opt ))+δ2(1+k tem ·(T-T opt ))); Among them, T opt Indicates standard temperature, pH opt represents the standard pH value, δ1 and δ2 represent weights, and v base Indicates the set reference reaction speed. The controller calculates the mixing speed adjustment value based on real-time data and outputs instructions to the variable frequency agitator.

5. The multi-stage oxidation treatment system and optimized operation method for high-salinity wastewater according to claim 1 is characterized in that: The reaction time is dynamically controlled according to the real-time temperature and pH value. According to the Arrhenius equation, a temperature-reaction rate model is constructed and then the pH oxidation efficiency is corrected to obtain the corrected reaction time: Among them, t base represents the set reference reaction time, R represents the gas constant, and Ea represents the reaction activation energy.

6. A high-salinity wastewater multi-stage oxidation treatment system and optimized operation method according to claim 1, characterized in that: The oxidation parameters of the reaction pools at each level include organic matter concentration, oxidant concentration, by-product concentration, temperature and pH value; a mathematical model between wastewater quality and oxidation reaction efficiency is constructed based on the SVM model according to historical operation data to obtain the oxidant dosage required to achieve the target degradation effect under specific initial conditions, and set a safe maximum addition threshold, while extracting the maximum value of the by-product concentration generated during the reaction as the by-product concentration threshold; the reaction conditions and oxidant dosage required to achieve a COD removal rate of 90% under the current water quality are determined through experiments to obtain the target degradation efficiency.

7. A high-salinity wastewater multi-stage oxidation treatment system and optimized operation method according to claim 1, characterized in that: The updating rules of the target degradation efficiency, the maximum oxidant dosage threshold and the byproduct concentration threshold include modifying the target condition of the target degradation efficiency to the reaction condition and oxidant dosage required to achieve a COD removal rate of 92%.

8. A high-salinity wastewater multi-stage oxidation treatment system and an optimized operation system, used to implement a high-salinity wastewater multi-stage oxidation treatment system and an optimized operation method as claimed in any one of claims 1 to 7, characterized in that: include: The data acquisition module collects oxidation parameters of each level of reaction tank through integrated sensors and processors; A data setting module sets the target degradation efficiency, the maximum oxidant addition threshold and the by-product concentration threshold based on the initial water quality; Sliding mode-PID composite controller building module, adjusting the oxidant dosage at each level through the sliding mode-PID composite controller; Dynamic oxidant parameter control strategy module, dynamically adjusts oxidant mixing speed and reaction time according to real-time temperature and pH value; In the data update module, if the byproduct concentration at any level is greater than 1.2 times the byproduct concentration threshold, or the cumulative reagent cost exceeds the set reagent cost threshold, it returns to S2, updates the target degradation efficiency, the maximum oxidant addition threshold and the byproduct concentration threshold, and triggers an alarm.

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