An automatic adjustment method and system for phosphorus removal dosing in integrated wastewater treatment equipment

Abstract

This invention belongs to the field of wastewater treatment technology, specifically relating to an integrated wastewater treatment equipment automatic phosphorus removal dosing adjustment method and system. The method includes: collecting redox potential in the anoxic tank, dissolved oxygen concentration in the aerobic tank, influent flow rate, and transmembrane pressure difference signals of the membrane module; obtaining the anaerobic phosphorus release suitability based on the redox potential, and the aerobic phosphorus uptake saturation based on the dissolved oxygen concentration, thereby determining the biological phosphorus removal activity index; obtaining the chemical demand coefficient by combining the feedforward load of the influent flow rate and the biological phosphorus removal activity index; calculating the membrane fouling safety damping factor based on the transmembrane pressure difference signal, and using the membrane fouling safety damping factor to correct the chemical demand coefficient to obtain the phosphorus removal compensation coefficient; and adjusting the operating frequency of the phosphorus removal dosing pump in response to changes in the phosphorus removal compensation coefficient. This invention dynamically adjusts the dosing amount based on the biological phosphorus removal activity and the membrane module status, reducing chemical consumption and protecting the membrane module while ensuring effluent quality.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology. More specifically, this invention relates to an automatic adjustment method and system for phosphorus removal dosing in an integrated wastewater treatment system. Background Technology

[0002] Integrated wastewater treatment equipment plays a vital role in decentralized wastewater treatment scenarios such as rural areas and remote industrial and mining areas. Among these processes, phosphorus removal is a key step in preventing eutrophication and ensuring that the effluent meets quality standards. Since integrated equipment typically employs a combination of biological and chemical phosphorus removal processes, and is significantly affected by fluctuations in influent load and environmental conditions, the effectiveness of biological phosphorus removal is often unstable. Therefore, adding chemical agents for auxiliary phosphorus removal becomes a necessary means to ensure stable total phosphorus levels in the effluent.

[0003] In related technologies, an open-loop control method based on flow ratio is commonly used for chemical phosphorus removal dosing. This method mainly involves installing a flow meter in the inlet pipeline. The controller directly adjusts the frequency of the dosing pump according to the collected instantaneous flow signal and the preset dosing ratio coefficient, thereby achieving linear control of the dosage of the chemical as the inlet water volume increases or decreases.

[0004] However, the linear dosing method based solely on flow rate in related technologies ignores the dynamic changes in the phosphorus removal capacity of the microorganisms within the biochemical system. When the biological phosphorus removal activity is high, adding the agent at a fixed ratio will lead to waste of reagents and increased production of chemical sludge, thus increasing operating costs. Secondly, this method lacks awareness and protection of the membrane module's operating status. The inorganic flocs generated by the chemical phosphorus removal agent can easily exacerbate membrane fouling. If high-intensity dosing continues when the transmembrane pressure difference of the membrane module is high, it will lead to irreversible blockage of the membrane pores, severely shortening the cleaning cycle and service life of the membrane module. Summary of the Invention

[0005] To address the technical problems of mismatch between reagent dosage and biological phosphorus removal activity, delayed response to influent hydraulic load shocks, and easy clogging of membrane modules due to lack of membrane protection mechanisms when linearly adding reagents based solely on flow rate, the present invention provides solutions in the following aspects.

[0006] In a first aspect, the present invention provides an integrated wastewater treatment equipment phosphorus removal dosing automatic adjustment method, comprising: collecting oxidation-reduction potential signals from an anoxic tank, dissolved oxygen concentration signals from an aerobic tank, instantaneous influent flow signals from the equipment, and transmembrane pressure difference signals from the membrane module, and using the difference between the current flow rate and the previous flow rate as the flow rate change characteristic; using the oxidation-reduction potential signal, dissolved oxygen concentration signal, instantaneous influent flow rate signal, transmembrane pressure difference signal, and flow rate change characteristic as target state characteristics; obtaining the anaerobic phosphorus release suitability of the target state characteristics based on the oxidation-reduction potential signal from the anoxic tank; and based on the dissolved oxygen concentration signal... The concentration signal is used to obtain the aerobic phosphorus uptake saturation of the target state characteristics; based on the anaerobic phosphorus release suitability and aerobic phosphorus uptake saturation, the biological phosphorus removal activity index of the target state characteristics is obtained; the hydraulic shock load intensity at the current moment is determined based on the instantaneous influent flow rate signal and flow rate change characteristics of the equipment, and the chemical demand coefficient is obtained based on the biological phosphorus removal activity index and hydraulic shock load intensity; the membrane fouling safety damping factor is calculated based on the transmembrane pressure difference signal of the membrane module, and the chemical demand coefficient is corrected using the membrane fouling safety damping factor to obtain the phosphorus removal compensation coefficient; the operating frequency of the phosphorus removal dosing pump is adjusted in response to the change of the phosphorus removal compensation coefficient.

[0007] This invention incorporates biological phosphorus removal activity into the control process, automatically reducing the use of chemical agents when biological treatment is effective, thus lowering operating costs and reducing the generation of chemical sludge. Furthermore, this invention combines flow rate change rate assessment of influent shock levels, proactively increasing chemical dosage when influent flow surges to compensate for deficiencies in biological treatment and resolving emission exceedances caused by response lag. Finally, this invention corrects the chemical demand coefficient using transmembrane pressure difference signals, forcibly reducing chemical dosage when membrane module pressure is too high, preventing solid particles from clogging membrane pores due to excessive chemical dosage and effectively extending membrane module lifespan. Finally, this invention achieves automatic adjustment of chemical phosphorus removal dosage by collecting redox potential in the anoxic tank, dissolved oxygen concentration in the aerobic tank, influent flow rate, and transmembrane pressure difference signals, and comprehensively assessing the biological phosphorus removal status, influent shock level, and membrane module operating status.

[0008] Preferably, the anaerobic phosphorus release suitability satisfies the following relationship: In the formula, The anaerobic phosphorus release suitability is defined by the target state characteristics. The redox potential signal in the anoxic pool is a characteristic of the target state. This is the preset critical threshold for phosphorus release potential. The preset potential response sensitivity coefficient, It is an exponential function with the natural constant as the base.

[0009] This invention compares the redox potential signal of the anoxic tank with the preset critical threshold for phosphorus release potential to determine whether the current environment is suitable for polyphosphate-accumulating bacteria to release phosphorus. It can accurately identify whether there is excessive nitrate or oxygen interference in the environment, so that the control system can promptly increase the compensation ratio of chemical agents when the environmental conditions are not conducive to phosphorus release, thus avoiding poor subsequent phosphorus removal effect due to the obstruction of biological phosphorus release.

[0010] Preferably, the aerobic phosphorus uptake saturation satisfies the following relationship: In the formula, The aerobic phosphorus uptake saturation is a characteristic of the target state. The dissolved oxygen concentration signal in the aerobic tank is part of the target state characteristics. The preset dissolved oxygen saturation rate constant, It is an exponential function with the natural constant as the base.

[0011] This invention examines the impact of dissolved oxygen concentration signals in an aerobic tank on phosphorus uptake behavior, assessing the driving force of current oxygen content on microbial phosphorus uptake metabolism. It reflects the phenomenon that microorganisms can efficiently uptake phosphorus only when oxygen is sufficient, preventing the control system from overestimating the biological phosphorus removal capacity under hypoxic conditions. This ensures that the assessment of chemical agent requirements matches the actual metabolic status of microorganisms, providing a basis for accurate chemical compensation.

[0012] Preferably, the biological phosphorus removal activity index satisfies the following relationship: In the formula, Biological phosphorus removal activity index representing the characteristics of the target state. The anaerobic phosphorus release suitability is defined by the target state characteristics. The aerobic phosphorus uptake saturation is a characteristic of the target state.

[0013] Preferably, the drug requirement coefficient satisfies the following relationship: In the formula, The drug requirement coefficient is a characteristic of the target state. The instantaneous influent flow rate signal of the equipment in the target state characteristics. The flow rate change feature is a characteristic within the target state features. Biological phosphorus removal activity index representing the characteristics of the target state. The preset flow reference gain, The preset shock response gain, The preset biological substitution intensity factor, It is an exponential function with the natural constant as the base.

[0014] This invention determines the chemical requirement coefficient by comprehensively considering the influent flow rate, flow rate change rate, and biological phosphorus removal activity index. It achieves the ability to capture the instantaneous acceleration characteristics of water flow using the flow rate change rate, and increase the dosage in advance before the flow peak arrives. By utilizing the biological phosphorus removal activity index, the calculated value of chemical chemical requirement can be significantly reduced when the biological activity is high, so as to better utilize the biological phosphorus removal capacity and achieve energy saving and consumption reduction.

[0015] Preferably, the step of obtaining the chemical demand coefficient based on the biological phosphorus removal activity index and the hydraulic shock load intensity further includes: when the hydraulic shock load intensity is less than zero, making the chemical demand coefficient zero.

[0016] Preferably, the phosphorus removal compensation coefficient satisfies the following relationship: In the formula, The phosphorus removal compensation coefficient is the characteristic of the target state. The drug requirement coefficient is a characteristic of the target state. The transmembrane pressure difference signal of the membrane module in the target state characteristics. The preset membrane module cleaning differential pressure threshold, This is the preset membrane protection cutoff index.

[0017] This invention corrects the chemical demand coefficient by using a membrane fouling safety damping factor based on the transmembrane pressure difference signal of the membrane module, and establishes a correlation protection between chemical phosphorus removal and membrane module status. As the transmembrane pressure difference approaches the cleaning threshold, the safety damping factor causes the calculated dosage to decrease rapidly, thereby prioritizing the reduction of chemical reagent dosage when the risk of membrane fouling is high, preventing chemical sludge from depositing on the membrane surface, and avoiding physical fouling of the membrane module in pursuit of phosphorus removal effect.

[0018] Preferably, the step of correcting the chemical demand coefficient using the membrane fouling safety damping factor to obtain the phosphorus removal compensation coefficient includes: in response to the transmembrane pressure difference signal of the membrane module being greater than the membrane module cleaning pressure difference threshold, setting the phosphorus removal compensation coefficient to zero.

[0019] Preferably, adjusting the operating frequency of the dephosphorization dosing pump in response to changes in the dephosphorization compensation coefficient includes: multiplying the dephosphorization compensation coefficient by a preset reference frequency conversion coefficient to obtain the theoretical target driving frequency; controlling the dephosphorization dosing pump to remain in standby mode in response to the theoretical target driving frequency being less than a preset minimum start-up threshold; driving the dephosphorization dosing pump to operate at the theoretical target driving frequency in response to the theoretical target driving frequency being greater than or equal to the minimum start-up threshold and less than or equal to a preset rated maximum operating frequency; and driving the dephosphorization dosing pump to operate at the rated maximum operating frequency in response to the theoretical target driving frequency being greater than the rated maximum operating frequency.

[0020] Secondly, the present invention provides an integrated wastewater treatment equipment phosphorus removal dosing automatic adjustment system, including a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the above-mentioned integrated wastewater treatment equipment phosphorus removal dosing automatic adjustment method is implemented.

[0021] By adopting the above technical solution, a computer program is generated for the above-mentioned automatic adjustment method for phosphorus removal and chemical dosing in an integrated sewage treatment plant, and stored in a memory for loading and execution by a processor. Terminal equipment is then manufactured based on the memory and processor for convenient use.

[0022] The beneficial effects of this invention are as follows: By integrating the oxidation-reduction potential and dissolved oxygen concentration signals of the biological treatment tank, this invention achieves real-time sensing and evaluation of the phosphorus removal capacity of microorganisms. It can automatically reduce the amount of chemical reagents used when microbial activity is high and the environment is suitable, prioritizing the removal of phosphates through microbial metabolism. This reduces reagent consumption costs and the amount of chemical sludge generated while ensuring effluent quality. This invention utilizes the characteristics of influent flow rate and its rate of change to identify the fluctuation trend of hydraulic load and establishes compensation measures for influent shocks. When the influent flow rate increases sharply, the system can increase the reagent dosage in advance before the water flow shock has a substantial impact on the biological treatment system, quickly filling the gap in biological treatment capacity. This effectively solves the problem of instantaneous discharge exceeding standards caused by the lag in response of traditional feedback control, maintaining a stable phosphorus removal effect even under severe influent fluctuations. When the membrane module filtration resistance increases and faces the risk of clogging, this invention will proactively limit the upper limit of chemical reagent dosage or stop dosing, preventing inorganic particles generated by excessive dosage from further aggravating membrane pore clogging, extending the cleaning cycle and service life of the membrane module, and reducing the maintenance frequency of the equipment. Attached Figure Description

[0023] Figure 1 This is a schematic flowchart illustrating an automatic adjustment method for phosphorus removal dosing in an integrated wastewater treatment system according to the present invention;

[0024] Figure 2 This is a schematic diagram illustrating the phosphorus removal dosing adjustment process in this invention. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0027] This invention discloses an automatic adjustment method for phosphorus removal dosing in an integrated wastewater treatment system, referring to... Figure 1 This includes steps S1-S7:

[0028] S1. The state characteristics of the integrated equipment's biochemical environment and hydraulic load are obtained through multi-sensor fusion.

[0029] Specifically, an oxidation-reduction potential sensor is installed in the anoxic tank of the integrated equipment, a dissolved oxygen concentration sensor is installed in the aerobic tank, an electromagnetic flow meter is installed in the influent pipeline or product water pump pipeline, and a pressure transmitter is installed in the negative pressure pipeline at the outlet of the membrane module. The oxidation-reduction potential signal from the anoxic tank, the dissolved oxygen concentration signal from the aerobic tank, the instantaneous influent flow rate signal of the equipment, and the transmembrane pressure difference signal of the membrane module are collected synchronously. The difference between the current flow rate and the previous flow rate is used as the flow rate change characteristic. The oxidation-reduction potential signal from the anoxic tank, the dissolved oxygen concentration signal from the aerobic tank, the instantaneous influent flow rate signal of the equipment, the flow rate change characteristic, and the transmembrane pressure difference signal of the membrane module at each moment are combined to form the state characteristic at that moment. The state characteristics at each moment constitute a state characteristic set.

[0030] S2. The permissibility of the environment for phosphorus release by polyphosphate-accumulating bacteria is measured by the redox potential of the anoxic tank, and the suitability for anaerobic phosphorus release is obtained.

[0031] It should be noted that in the biological phosphorus removal mechanism of the anaerobic-aerobic process, polyphosphate-accumulating bacteria must first be in a strictly anaerobic or anoxic environment to synthesize intracellular energy storage substances and release phosphates using easily degradable organic matter. Excessively high environmental potential will enhance the competitive inhibition of polyphosphate-accumulating bacteria by nitrates or oxygen, leading to the obstruction of the phosphorus release reaction. Therefore, this invention uses the redox potential of the anoxic tank to measure the permissibility of the environment for polyphosphate-accumulating bacteria's phosphorus release behavior, thus obtaining the suitability for anaerobic phosphorus release.

[0032] Specifically, any state feature from the set of state features is taken as the target state feature. The redox potential signal of the anoxic tank is extracted from the target state feature. The anaerobic phosphorus release suitability is obtained based on the difference between the extracted redox potential signal of the anoxic tank and the ideal phosphorus release potential threshold.

[0033] Specifically, the suitability for anaerobic phosphorus release satisfies the following relationship:

[0034] ;

[0035] In the formula, The anaerobic phosphorus release suitability is defined by the target state characteristics. The redox potential signal in the anoxic pool is a characteristic of the target state. This is the preset critical threshold for phosphorus release potential. The preset potential response sensitivity coefficient, In this embodiment, it is an exponential function with the natural constant as the base. for The implementers can determine the implementation based on the actual situation. The value of .

[0036] in, This represents the degree of disadvantage of the current potential environment in the target state characteristics relative to the preset ideal phosphorus release conditions. The smaller the value, the stronger the reducing power of the environment, which is more conducive to phosphorus release metabolism by polyphosphate-accumulating bacteria, thus increasing the anaerobic phosphorus release suitability of the target state characteristics and characterizing an excellent phosphorus release environment; The larger the value, the stronger the environmental oxidation, which leads to a rapid decline in the anaerobic phosphorus release suitability of the target state characteristics, approaching 0, indicating that phosphorus release behavior is strongly inhibited.

[0037] S3. Calculate the driving force of the environment on the phosphorus uptake behavior of polyphosphate-accumulating bacteria based on the dissolved oxygen concentration signal of the aerobic pool in the target state characteristics, and obtain the aerobic phosphorus uptake saturation.

[0038] It should be noted that phosphorus uptake by polyphosphate-accumulating bacteria is an energy-intensive process, relying on energy generated by aerobic respiration. Only under sufficient dissolved oxygen conditions can polyphosphate-accumulating bacteria oxidize intracellular energy storage substances to achieve excessive phosphorus uptake. Insufficient dissolved oxygen concentration limits the efficiency of the electron transport chain, leading to a decrease in the phosphorus uptake rate. Therefore, this invention calculates the driving force of the environment on the phosphorus uptake behavior of polyphosphate-accumulating bacteria based on the dissolved oxygen concentration signal of the aerobic pool in the target state characteristics, obtains the aerobic phosphorus uptake saturation, and measures the driving ability of the current dissolved oxygen concentration on the phosphorus uptake metabolic rate.

[0039] Specifically, the dissolved oxygen concentration signal of the aerobic tank is extracted from the target state characteristics. The aerobic phosphorus uptake saturation is then obtained based on the dissolved oxygen concentration signal.

[0040] Specifically, the aerobic phosphorus uptake saturation satisfies the following relationship:

[0041] ;

[0042] In the formula, The aerobic phosphorus uptake saturation is a characteristic of the target state. The dissolved oxygen concentration signal in the aerobic tank is part of the target state characteristics. The preset dissolved oxygen saturation rate constant, In this embodiment, it is an exponential function with the natural constant as the base. The value is 0.8, which can be determined by the implementers based on the actual situation. .

[0043] in, This represents the degree to which dissolved oxygen concentration in the target state characteristics restricts the metabolic rate. The smaller this value, the stronger the dissolved oxygen concentration signal in the aerobic pool within the target state characteristics, indicating a more abundant electron acceptor in the aerobic pool and less restricted phosphorus uptake metabolism by polyphosphate-accumulating bacteria. The smaller the value, the greater the aerobic phosphorus uptake saturation of the target state characteristic, indicating that phosphorus uptake efficiency has reached saturation; the larger the value, the smaller the dissolved oxygen concentration signal in the aerobic pool of the target state characteristic, indicating that dissolved oxygen has become a limiting factor. The larger the value, the more significant the decrease in the aerobic phosphorus uptake saturation characteristic of the target state, indicating insufficient phosphorus uptake capacity.

[0044] S4. Determine the biological phosphorus removal activity index based on the anaerobic phosphorus release suitability and aerobic phosphorus uptake saturation.

[0045] It should be noted that the overall efficiency of biological phosphorus removal follows the weakest link effect, meaning that the final phosphorus removal effect depends on the weaker link between the phosphorus release stage and the phosphorus uptake stage. If phosphorus release is insufficient, even if the dissolved oxygen in the aerobic stage is sufficient, efficient phosphorus uptake cannot be achieved. Therefore, this invention determines the biological phosphorus removal activity index based on the suitability of anaerobic phosphorus release and the saturation of aerobic phosphorus uptake, and evaluates the potential of biological systems to replace chemical phosphorus removal.

[0046] Specifically, the biological phosphorus removal activity index is determined based on the anaerobic phosphorus release suitability and the aerobic phosphorus uptake saturation of the target state characteristics.

[0047] Specifically, the biological phosphorus removal activity index satisfies the following relationship:

[0048] ;

[0049] In the formula, Biological phosphorus removal activity index representing the characteristics of the target state. The anaerobic phosphorus release suitability is defined by the target state characteristics. The aerobic phosphorus uptake saturation is a characteristic of the target state.

[0050] Among them, the biological phosphorus removal activity index of the target state characteristics represents the comprehensive efficiency of the entire biological phosphorus removal process. The larger the value, the more likely the environmental conditions in both the phosphorus release and phosphorus uptake stages are in the optimal range, the higher the contribution of the biological system to phosphorus removal, and the stronger the endogenous phosphorus removal capacity of the system. The smaller the value, the more likely there is a deficiency in the environmental conditions at any stage, leading to a decrease in the overall biological phosphorus removal capacity, which means that external chemical agents are needed for compensation.

[0051] S5. By combining the feedforward load of the instantaneous influent flow signal in the comprehensive target state characteristics with the substitution effect of biological phosphorus removal, the chemical demand coefficient is obtained.

[0052] It should be noted that rural sewage discharge is characterized by significant and drastic flow fluctuations. Rapid increases in influent flow can cause a lag in the biological system's treatment capacity, necessitating a rapid increase in chemical dosage to compensate for the shortfall in biological treatment. Simultaneously, chemical phosphorus removal serves as a supplementary method to biological phosphorus removal. When the biological system's activity is high, the dosage of chemical agents should be reduced to save costs and decrease sludge production. Therefore, this invention integrates the feedforward load of the instantaneous influent flow signal in the target state characteristics with the substitution effect of biological phosphorus removal to obtain the chemical demand coefficient.

[0053] Specifically, the instantaneous influent flow rate signal and flow rate change characteristics of the equipment are extracted from the target state characteristics, and the biological phosphorus removal activity index of the target state characteristics calculated in step S4 is obtained. The hydraulic shock load intensity at the current moment is determined based on the instantaneous influent flow rate signal and flow rate change characteristics of the equipment; the chemical demand coefficient is obtained based on the biological phosphorus removal activity index and the hydraulic shock load intensity.

[0054] Specifically, the drug requirement coefficient satisfies the following relationship:

[0055] ;

[0056] In the formula, The drug requirement coefficient is a characteristic of the target state. The instantaneous influent flow rate signal of the equipment in the target state characteristics. The flow rate change feature is a characteristic within the target state features. Biological phosphorus removal activity index representing the characteristics of the target state. The preset flow reference gain, The preset shock response gain, The preset biological substitution intensity factor, In this embodiment, the function is an exponential function with the natural constant as its base. =1, It is 0.5. The value is 1.2, and the implementers can determine it based on the actual situation. , and .

[0057] in, The hydraulic shock load intensity represents the feedforward chemical dosing demand under hydraulic shock load in the target state characteristics. A larger value indicates a larger instantaneous influent flow signal and a faster increase in flow rate, indicating that the system is under shock load and the basic dosing demand is higher; a smaller value indicates a more stable hydraulic load and a lower basic dosing demand. The biological phosphorus removal activity index, representing the target state characteristics, offsets the demand for chemical agents. A smaller value indicates a higher biological phosphorus removal activity index for the target state characteristics, a larger proportion of biological phosphorus removal, and a lower theoretical demand for chemical agents; a larger value indicates inhibited biological activity, requiring a higher dosage of chemical agents.

[0058] It should be added that, in order to avoid a sharp drop in influent flow rate that would cause the hydraulic impact load intensity to be less than zero, thus making the chemical demand coefficient negative, the chemical demand coefficient should be 0 when it is less than zero.

[0059] S6. Calculate the membrane fouling safety damping factor based on the transmembrane pressure difference signal of the membrane module in the target state characteristics, correct the reagent demand coefficient, and obtain the phosphorus removal compensation coefficient.

[0060] It should be noted that the inorganic flocs formed by chemical phosphorus removal agents are a significant cause of pore blockage in flat-plate membranes of membrane bioreactors. When the membrane module is already under high pressure differential, continuing to add chemicals at the theoretically required intensity will lead to an irreversible decrease in membrane flux, and may even trigger a shutdown for cleaning. Therefore, this invention calculates the membrane fouling safety damping factor based on the transmembrane pressure differential signal of the membrane module in the target state characteristics, corrects the chemical demand coefficient, and obtains the phosphorus removal compensation coefficient.

[0061] Specifically, the transmembrane pressure difference signal of the membrane module is extracted from the target state characteristics. Based on the ratio of the current transmembrane pressure difference signal of the membrane module to the cleaning pressure difference threshold, the chemical demand coefficient is corrected to determine the phosphorus removal compensation coefficient.

[0062] Specifically, the phosphorus removal compensation coefficient satisfies the following relationship:

[0063] ;

[0064] In the formula, The phosphorus removal compensation coefficient is the characteristic of the target state. The drug requirement coefficient is a characteristic of the target state. The transmembrane pressure difference signal of the membrane module in the target state characteristics. The preset membrane module cleaning differential pressure threshold, In this embodiment, the preset membrane protection cutoff index is used. The pressure is 25 kPa. The value is 4, and the implementers can determine the number based on the actual situation. and .

[0065] in, For safety damping factor, The smaller the value, the closer the transmembrane pressure difference signal of the membrane module in the target state characteristics is to the preset cleaning pressure difference threshold. The higher the risk of membrane fouling, the more the chemical demand coefficient should be corrected downward to reduce the final dosage and prevent complete membrane clogging. A larger value indicates that the membrane is more likely to be in a safe operating range. The phosphorus removal compensation coefficient should be larger to allow the system to be added in full according to theoretical requirements.

[0066] It should be added that when the membrane module is severely clogged... At this point, the phosphorus removal compensation coefficient is adjusted. If the value is 0, the dosing should be forcibly stopped to protect the membrane assembly.

[0067] S7. Adjust the operating frequency of the phosphorus removal dosing pump in response to changes in the phosphorus removal compensation coefficient.

[0068] Specifically, the rated maximum operating frequency and minimum start-up threshold of the phosphorus removal dosing pump are preset. The theoretical target driving frequency is obtained by multiplying the phosphorus removal compensation coefficient of the target state characteristics by a preset reference frequency conversion coefficient. In response to the theoretical target driving frequency being less than the minimum start-up threshold, a shutdown control signal is generated to instruct the phosphorus removal dosing pump to remain in standby mode; in response to the theoretical target driving frequency being greater than or equal to the minimum start-up threshold and less than or equal to the rated maximum operating frequency, the phosphorus removal dosing pump is driven to continuously add phosphorus removal agents to the inlet of the anoxic or aerobic tank at the theoretical target driving frequency; in response to the theoretical target driving frequency exceeding the rated maximum operating frequency, the phosphorus removal dosing pump is driven to operate at the rated maximum operating frequency, thereby achieving adaptive dynamic adjustment of the phosphorus removal agent dosage according to biological activity, hydraulic load, and membrane fouling status. The rated maximum operating frequency is 50Hz, the minimum start-up threshold is 5Hz, and the reference frequency conversion coefficient is 5.

[0069] For example, Figure 2 This diagram illustrates the phosphorus removal dosing adjustment process in this invention. As can be seen from the diagram, compared to the traditional method of dosing based on flow rate ratio, this invention can sense and fully utilize the biological phosphorus removal activity to reduce chemical reagent consumption and lower operating costs. Secondly, the instantaneous peak in the diagram indicates that this invention can capture sudden changes in influent flow rate and rapidly increase the dosage to compensate for the load gap, thus solving the risk of exceeding standards caused by the lag in response of existing methods. The forced drop in the curve at the end of operation indicates that the membrane fouling safety damping factor has been successfully triggered, and the dosing is automatically stopped when the transmembrane pressure difference approaches the threshold, effectively preventing irreversible blockage of the membrane module.

[0070] This invention also discloses an integrated wastewater treatment equipment phosphorus removal dosing automatic adjustment system, including a processor and a memory. The memory stores computer program instructions, and when the computer program instructions are executed by the processor, an integrated wastewater treatment equipment phosphorus removal dosing automatic adjustment method according to the present invention is implemented.

[0071] The system also includes other components well known to those skilled in the art, such as communication buses and communication interfaces, the settings and functions of which are known in the art and will not be described in detail here.

Claims

1. An automatic adjustment method for phosphorus removal dosing in an integrated wastewater treatment system, characterized in that, include: The redox potential (RPP) signal of the anoxic tank, the dissolved oxygen concentration (DOC) signal of the aerobic tank, the instantaneous influent flow rate of the equipment, and the transmembrane pressure difference signal of the membrane module were collected. The difference between the current flow rate and the previous flow rate was used as the flow rate change characteristic. The RRP signal, DOC signal, DOC signal, DOC signal, transmembrane pressure difference signal, and flow rate change characteristic were used as the target state characteristics. The anaerobic phosphorus release suitability of the target state characteristics was obtained based on the RRP signal of the anoxic tank. The aerobic phosphorus uptake saturation of the target state characteristics was obtained based on the DOC signal. The biological phosphorus removal activity index of the target state characteristics was obtained based on the anaerobic phosphorus release suitability and the aerobic phosphorus uptake saturation. The hydraulic shock load intensity at the current moment is determined based on the instantaneous influent flow signal and flow change characteristics of the equipment, and the chemical demand coefficient is obtained based on the biological phosphorus removal activity index and the hydraulic shock load intensity; the membrane fouling safety damping factor is calculated based on the transmembrane pressure difference signal of the membrane module, and the chemical demand coefficient is corrected using the membrane fouling safety damping factor to obtain the phosphorus removal compensation coefficient. The operating frequency of the phosphorus removal dosing pump is adjusted in response to changes in the phosphorus removal compensation coefficient; The suitability of anaerobic phosphorus release satisfies the following relationship: ; The anaerobic phosphorus release suitability is defined by the target state characteristics. The redox potential signal in the anoxic pool is a characteristic of the target state. This is the preset critical threshold for phosphorus release potential. The preset potential response sensitivity coefficient, It is an exponential function with the natural constant as its base; The aerobic phosphorus uptake saturation satisfies the following relationship: ; The aerobic phosphorus uptake saturation is a characteristic of the target state. The dissolved oxygen concentration signal in the aerobic tank is part of the target state characteristics. This is the preset dissolved oxygen saturation rate constant; The biological phosphorus removal activity index satisfies the following relationship: ; The biological phosphorus removal activity index is a characteristic of the target state. The drug requirement coefficient satisfies the following relationship: ; The drug requirement coefficient is a characteristic of the target state. The instantaneous influent flow rate signal of the equipment in the target state characteristics. The flow rate change feature is a characteristic within the target state characteristics. The preset flow reference gain, The preset shock response gain, The preset biological substitution intensity factor; The phosphorus removal compensation coefficient satisfies the following relationship: ; The phosphorus removal compensation coefficient is the characteristic of the target state. The transmembrane pressure difference signal of the membrane module in the target state characteristics. The preset membrane module cleaning differential pressure threshold, The preset membrane protection cutoff index, It is a membrane fouling safety damping factor.

2. The automatic adjustment method for phosphorus removal dosing in an integrated wastewater treatment system according to claim 1, characterized in that, The method of obtaining the chemical demand coefficient based on the biological phosphorus removal activity index and the hydraulic impact load intensity also includes: when the hydraulic impact load intensity is less than zero, making the chemical demand coefficient zero.

3. The automatic adjustment method for phosphorus removal dosing in an integrated wastewater treatment system according to claim 1, characterized in that, The step of using a membrane fouling safety damping factor to correct the chemical demand coefficient and obtain a phosphorus removal compensation coefficient includes: in response to the transmembrane pressure difference signal of the membrane module being greater than the membrane module cleaning pressure difference threshold, setting the phosphorus removal compensation coefficient to zero.

4. The automatic adjustment method for phosphorus removal dosing in an integrated wastewater treatment system according to claim 1, characterized in that, The method of adjusting the operating frequency of the dephosphorization dosing pump in response to changes in the dephosphorization compensation coefficient includes: multiplying the dephosphorization compensation coefficient by a preset reference frequency conversion coefficient to obtain the theoretical target driving frequency; controlling the dephosphorization dosing pump to remain in standby mode in response to the theoretical target driving frequency being less than a preset minimum start-up threshold; driving the dephosphorization dosing pump to operate at the theoretical target driving frequency in response to the theoretical target driving frequency being greater than or equal to the minimum start-up threshold and less than or equal to the preset rated maximum operating frequency; and driving the dephosphorization dosing pump to operate at the rated maximum operating frequency in response to the theoretical target driving frequency being greater than the rated maximum operating frequency.

5. An integrated wastewater treatment equipment phosphorus removal dosing automatic adjustment system, characterized in that, include: A processor and a memory, wherein the memory stores computer program instructions that, when executed by the processor, implement an automatic adjustment method for phosphorus dosing in an integrated wastewater treatment plant according to any one of claims 1-4.

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