Dynamic convolution-based sewage treatment aerobic section nitrogen conversion path prediction method

Abstract

The invention discloses a dynamic convolution-based sewage treatment aerobic section nitrogen conversion path prediction method, and relates to the technical field of sewage treatment, and the method comprises the following steps: calculating an instantaneous air inlet flow according to process setting parameters of a sewage treatment aerobic section, and calculating soil arch retardation invalid work based on the instantaneous air inlet flow and instantaneous pressure of an aeration pipe network of the aerobic section; calculating the structured loss ratio of the bubble form based on the invalid work of the soil arch retardation; determining an inherent structure constant based on a design water depth parameter of a sewage treatment aerobic section and an elastic modulus parameter of an aerator membrane; a nitrite accumulation path coefficient is calculated based on the intrinsic structure constant and the bubble morphological structured loss ratio. According to the method, the accuracy of predicting the concentration of nitrides such as nitrite in the effluent under the working condition of sludge deposition is improved.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to a method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution. Background Technology

[0002] In the aerobic biological stage of wastewater treatment, plug-flow aeration tanks are a widely used treatment structure. They supply oxygen to the mixed liquor through an aeration system, supporting nitrifying bacteria in converting ammonia nitrogen into nitrate, thereby achieving nitrogen removal. The tank is typically rectangular, with internal guide walls to guide the water flow into a plug flow pattern, theoretically approaching a uniform piston flow. The aeration system commonly uses microporous aerators, utilizing the micropores of rubber diaphragms to release fine bubbles, achieving high oxygen mass transfer efficiency. In actual operation, because the rheological properties of activated sludge change with its concentration and temperature, sludge tends to gradually deposit at the bottom of the tank, especially in low-velocity areas such as the corners of the guide walls, forming a sludge layer covering the aerator surface.

[0003] However, the aforementioned deposited sludge layer raises a key technical issue: the sediment forms a stable arch-like structure under the aeration airflow, altering the gas release path and bubble morphology. The appearance of large bubbles significantly reduces oxygen mass transfer efficiency, causing localized dissolved oxygen deficiency, which in turn interferes with the nitrification process and leads to nitrite accumulation. Existing nitrogen conversion pathway prediction methods are mostly based on fixed process parameters and macroscopic influent and effluent data to build models, failing to effectively identify and quantify the decrease in microscopic mass transfer efficiency caused by sludge deposition on the aerator surface. Therefore, when this situation occurs, existing models cannot accurately predict the actual reaction process, leading to inaccurate judgments of effluent nitrogen oxide concentrations, and consequently affecting the control of subsequent processes. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing models in the prior art, which cannot accurately predict the actual reaction process and thus lead to inaccurate judgment of nitrogen concentration in effluent. The invention proposes a method for predicting nitrogen conversion pathways in the aerobic stage of wastewater treatment based on dynamic convolution.

[0005] To address the problems existing in the prior art, the present invention adopts the following technical solution: A method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution includes: S1. Calculate the instantaneous air intake flow rate based on the process setting parameters of the aerobic section of the wastewater treatment, and calculate the ineffective work of soil arching based on the instantaneous air intake flow rate and the instantaneous pressure of the aeration pipe network in the aerobic section. S2. Calculate the bubble morphology structured loss ratio based on the ineffective work of soil arch resistance; S3. Determine the inherent structural constants based on the design water depth parameters of the aerobic section of the wastewater treatment and the elastic modulus parameters of the aerator membrane; S4. Calculate the nitrite accumulation path coefficient based on the inherent structural constant and the bubble morphology structuring loss ratio; S5. Dynamic feedback calibration of the real-time prediction results of nitrogen conversion pathway based on nitrite accumulation pathway coefficient.

[0006] Preferably, the instantaneous air inflow rate is calculated based on the process setting parameters of the aerobic section of wastewater treatment, including: The design air volume is adjusted based on the process parameters of the aerobic section of the wastewater treatment system. The instantaneous intake airflow is obtained by superimposing periodic sinusoidal disturbance signals on the basic design air volume. The formula for calculating the instantaneous intake airflow is as follows: In the formula, It is the instantaneous intake flow rate at time t. It is the basic design air volume. It is the amplitude of the disturbance. It is the angular frequency of the disturbance, and t is the time indicator.

[0007] Preferably, the design air volume is adjusted according to the process parameters of the aerobic section of wastewater treatment, including: The concentration of activated sludge at the bottom of the aerobic section of the wastewater treatment plant is collected in real time using an online sludge concentration detector. The thickness of the deposited sludge layer in the aerobic section of wastewater treatment is collected in real time using an ultrasonic sludge level gauge. The activated sludge concentration was nonlinearly fitted and converted based on a pre-acquired database of activated sludge rheological properties to obtain the sludge yield stress value. The critical aerodynamic thrust is obtained by multiplying the thickness of the deposited sludge layer and the sludge yield stress value. Based on the critical aerobic thrust, the historical process design air volume of the aerobic section of the wastewater treatment is corrected by aerobic power matching to obtain the corrected design air volume.

[0008] Preferably, the calculation of the soil arching ineffective work based on the instantaneous air intake flow rate and the instantaneous pressure of the aeration network in the aerobic section includes: The instantaneous pressure of the aeration pipeline network in the aerobic section is collected, and the instantaneous pressure and instantaneous air intake flow are synchronized in time. The disturbance angular frequency is periodically converted to obtain the disturbance period; The ineffective work of soil arching is calculated based on the disturbance period, instantaneous pressure, and instantaneous air intake flow rate. The formula for calculating the ineffective work of soil arching is as follows: In the formula, It is an ineffective function of soil arching obstruction. It is the disturbance period. It is the instantaneous intake flow rate at time t. It is the instantaneous pressure at time t.

[0009] Preferably, the calculation of the bubble morphology structuring loss ratio based on the ineffective work of soil arching includes: The instantaneous aerodynamic power is obtained by multiplying the instantaneous intake flow rate and instantaneous pressure. The total aerodynamic input power is obtained by integrating the instantaneous aerodynamic power based on the disturbance period. Dividing the ineffective work of soil arch obstruction by the total aerodynamic input work yields the bubble morphology structure loss ratio.

[0010] Preferably, the inherent structural constants are determined based on the design water depth parameters of the aerobic section of the wastewater treatment process and the elastic modulus parameters of the aerator membrane, including: Obtain the design water depth parameters for the aerobic section of wastewater treatment; Obtain the elastic modulus parameter of the aerator diaphragm; The hydrostatic pressure impedance component is obtained by multiplying the design water depth parameters with the preset first weighting coefficient. The elastic modulus parameter is multiplied by a preset second weighting coefficient to obtain the diaphragm tension impedance component. The inherent structural constants are obtained by weighted summation of the hydrostatic pressure impedance component and the diaphragm tension impedance component.

[0011] Preferably, the nitrite accumulation path coefficient is calculated based on the inherent structural constant and the bubble morphology structuring loss ratio, including: The total path deflection impedance is obtained by adding the square of the structured loss ratio of the bubble morphology to the square of the inherent structure constant. The nitrite accumulation path coefficient is obtained by dividing the square of the bubble morphology structured loss ratio by the total path deflection impedance.

[0012] Preferably, dynamic feedback calibration is performed on the real-time prediction results of nitrogen transformation pathways based on nitrite accumulation pathway coefficients, including: Obtain the design carbon source dosing flow rate for the denitrification process; The carbon source dosing execution flow rate was calculated and corrected based on the nitrite accumulation path coefficient and the designed carbon source dosing flow rate. Dynamic feedback calibration is performed based on the real-time prediction results of the nitrogen conversion pathway using the modified carbon source addition execution flow rate.

[0013] Preferably, the formula for calculating the carbon source dosing flow rate is as follows: In the formula, It is to adjust the carbon source addition execution flow rate. It is about designing the carbon source addition flow rate. It is the nitrite accumulation pathway coefficient.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. This method, by introducing periodic disturbance signals and real-time pressure monitoring, can accurately identify and quantify the obstructive effect of the arch-like structure formed by sludge deposition on the surface of the aerator on the gas release process. By calculating the ineffective work of the soil arch obstruction and the loss ratio of bubble morphology structuring, the microscopic physical changes that were originally difficult to observe directly are transformed into quantifiable energy loss indicators. This enables real-time assessment of the actual mass transfer efficiency decay of the aeration system, overcoming the shortcomings of existing models in failing to detect such dynamic physical changes.

[0015] 2. By combining the loss ratio of bubble morphology structure with the structural constant reflecting the inherent characteristics of the system, this method can accurately calculate the nitrite accumulation path coefficient. The nitrite accumulation path coefficient is directly related to the causal relationship between insufficient dissolved oxygen caused by local aeration failure and the obstruction of nitrification reaction. This allows the prediction model of nitrogen conversion path to dynamically reflect the changes in the biochemical state in the actual reactor, improving the accuracy of predicting the concentration of nitrite and other nitrogen compounds in the effluent under sludge deposition conditions.

[0016] 3. Based on the obtained nitrite accumulation path coefficient, this method further realizes dynamic feedback calibration of carbon source addition in subsequent denitrification process. By adaptively adjusting the carbon source addition rate to match the actual nitrogen speciation distribution, it avoids waste and secondary pollution risks caused by excessive carbon source addition, and also prevents incomplete denitrification due to insufficient carbon source. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a flowchart illustrating a method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution, provided in an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0019] Example: This example provides a method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution. See [link to example]. Figure 1 Specifically, including: S1. Calculate the instantaneous air intake flow rate based on the process setting parameters of the aerobic section of the wastewater treatment, and calculate the ineffective work of soil arching based on the instantaneous air intake flow rate and the instantaneous pressure of the aeration pipe network in the aerobic section. In an embodiment of the present invention, calculating the instantaneous airflow rate based on the process setting parameters of the aerobic section of wastewater treatment includes: The design air volume is adjusted based on the process parameters of the aerobic section of the wastewater treatment system. In an embodiment of the present invention, setting a modified design air volume based on the process setting parameters of the aerobic section of wastewater treatment includes: The concentration of activated sludge at the bottom of the aerobic section of the wastewater treatment plant is collected in real time using an online sludge concentration detector. The thickness of the deposited sludge layer in the aerobic section of wastewater treatment is collected in real time using an ultrasonic sludge level gauge. Specifically, regarding the steps for real-time acquisition of the sludge layer thickness in the aerobic section of wastewater treatment using an ultrasonic sludge level gauge, the ultrasonic sludge level gauge must first be installed above the aerobic section tank, corresponding to the area at the bottom where sludge is easily deposited. Then, the ultrasonic sludge level gauge is configured, setting its ultrasonic emission frequency to a preset value suitable for the sludge medium, and the detection cycle to a preset real-time acquisition interval. After configuration, the ultrasonic sludge level gauge is activated, emitting ultrasonic signals towards the bottom of the aerobic section. Once the ultrasonic signal contacts the upper surface of the sludge layer, it is reflected. The ultrasonic sludge level gauge receives this reflected signal and records the time difference between emission and reception. Combined with the ultrasonic propagation speed corresponding to the mixed liquor medium in the aerobic section, the distance from the installation position of the ultrasonic sludge level gauge to the upper surface of the sludge layer is calculated. This distance is then subtracted from the pre-determined fixed height from the installation position of the ultrasonic sludge level gauge to the bottom of the aerobic section tank to obtain the sludge layer thickness. The above operation is repeated according to the preset real-time acquisition interval to continuously acquire real-time data on the sludge layer thickness.

[0020] The activated sludge concentration was nonlinearly fitted and converted based on a pre-acquired database of activated sludge rheological properties to obtain the sludge yield stress value. Specifically, the online sludge concentration detector is a device used to obtain the ratio of the mass of activated sludge to the volume of the corresponding mixed liquor in the bottom mixed liquor of the aerobic stage of wastewater treatment in real time; the activated sludge concentration is the ratio of the mass of activated sludge to the volume of the mixed liquor in the bottom mixed liquor of the aerobic stage of wastewater treatment, reflecting the density of the microbial community in the mixed liquor; the ultrasonic sludge level gauge is a device that transmits and receives ultrasonic signals and calculates the distance from the upper surface of the deposited sludge layer in the aerobic stage of wastewater treatment to the installation position of the detection device based on the signal propagation time and the characteristics of the medium; the thickness of the deposited sludge layer is the vertical dimension of the layered structure formed by the sludge deposited at the bottom of the aerobic stage of wastewater treatment, reflecting the degree of sludge accumulation; the activated sludge rheological property parameter library is a collection of rheological data corresponding to different activated sludge concentrations obtained in advance through experiments, which can be used to correlate activated sludge concentration with sludge yield stress value; the sludge yield stress value is the minimum shear stress required to make activated sludge start to flow from a static state, reflecting the anti-flow characteristics of activated sludge as a fluid.

[0021] Specifically, for the step of nonlinearly fitting and converting activated sludge concentration to obtain the sludge yield stress value based on a pre-acquired activated sludge rheological characteristic parameter library, it is necessary to establish the activated sludge rheological characteristic parameter library in advance. Specifically, multiple sets of activated sludge concentration samples with different values ​​are selected. For each set of concentration samples, the yield stress of activated sludge at that concentration is measured using a rheometer, and the yield stress value corresponding to each set of concentration samples is recorded. The correlation data of all concentration samples and corresponding yield stress values ​​are compiled into the activated sludge rheological characteristic parameter library. Subsequently, the activated sludge concentration data at the bottom of the aerobic section of the wastewater treatment plant is acquired in real time by the online sludge concentration monitoring instrument. At least three sets of concentration-yield stress correlation data that are close to the real-time activated sludge concentration value are retrieved from the activated sludge rheological characteristic parameter library. A polynomial nonlinear fitting algorithm is used to establish a fitting function with concentration as the independent variable and yield stress as the dependent variable. The real-time activated sludge concentration value is substituted into the fitting function to calculate the corresponding sludge yield stress value.

[0022] The critical aerodynamic thrust is obtained by multiplying the thickness of the deposited sludge layer and the sludge yield stress value. Based on the critical aerobic thrust, the historical process design air volume of the aerobic section of the wastewater treatment is corrected by aerobic power matching to obtain the corrected design air volume.

[0023] Specifically, the critical aerodynamic thrust refers to the physical quantity obtained by multiplying the thickness of the deposited sludge layer by the sludge yield stress value. It represents the minimum aerobic force required to cause the deposited sludge layer to move out of its static state and begin to flow. The historical process design air volume refers to the aeration inlet flow rate benchmark value set by the aerobic section of wastewater treatment based on the basic process conditions during past operation. The aerobic power matching correction refers to the parameter adjustment operation of the historical process design air volume based on the energy requirement corresponding to the critical aerobic thrust. It is used to match the aerobic power output of the aeration system with the thrust required to break through the deposited sludge layer. The corrected design air volume refers to the aeration inlet flow rate value obtained after aerobic power matching correction. It serves as the flow rate benchmark parameter for subsequent aeration operation of the aerobic section of wastewater treatment.

[0024] Specifically, first, retrieve the historical process design air volume corresponding to the aerobic section of the wastewater treatment plant, as well as the aeration blower model suitable for that air volume. Simultaneously, obtain the performance curve provided by the manufacturer for that blower model. This curve must include the relationship between air volume and air pressure, and air volume and power. Next, collect system parameters such as the design water depth, aeration pipeline length, pipe diameter, inner wall roughness, aeration head type, and installation density of the aerobic section of the wastewater treatment plant. Then, calculate the additional air pressure required to overcome the static state of the deposited sludge layer based on the critical aerodynamic thrust value and fluid mechanics principles. Calculate the hydrostatic pressure using the design water depth. Based on the pipeline parameters, calculate the friction loss and local resistance, and determine the aeration head resistance based on the aeration head type. Finally, calculate the total pipeline pressure (additional air pressure, hydrostatic pressure, etc.). The total target air pressure is obtained by superimposing the resistance and the aerator head resistance. Then, the curve position corresponding to the total target air pressure is found in the fan performance curve. The horizontal correlation between the position and the power-air volume is used to determine the target aerodynamic power required to meet the critical aerodynamic thrust. The corresponding air volume value is then located on the power-air volume correlation curve based on the target aerodynamic power to obtain the preliminary corrected air volume. After that, it is checked whether the preliminary corrected air volume is within the high-efficiency operating range marked on the fan performance curve. If it deviates, the air volume is finely adjusted to the high-efficiency range within the allowable range of the total target air pressure. Finally, the aerodynamic thrust corresponding to the finely adjusted air volume is verified through simulation operation to see if it is not less than the critical aerodynamic thrust. After confirming that the requirements are met, the air volume is the corrected design air volume.

[0025] The instantaneous intake airflow is obtained by superimposing periodic sinusoidal disturbance signals on the basic design air volume. The formula for calculating the instantaneous intake airflow is as follows: In the formula, It is the instantaneous intake flow rate at time t. It is the basic design air volume. It is the amplitude of the disturbance. It is the angular frequency of the disturbance, and t is the time indicator.

[0026] Specifically, the basic design air volume refers to the pre-set baseline value of the air intake flow rate during the operation of the aerobic section aeration system in wastewater treatment, which is the basic flow parameter for subsequent perturbation treatment of the air volume; the periodic sinusoidal perturbation signal refers to a signal that changes periodically with time according to a sinusoidal function, which is used to apply fluctuation adjustments to the basic design air volume; the instantaneous air intake flow rate refers to the actual output air intake flow rate of the aerobic section aeration system in wastewater treatment at a specific time point, which is the real-time flow result obtained by superimposing the periodic sinusoidal perturbation signal on the basic design air volume; time t refers to a physical quantity that identifies a specific time point in the time process, with different t corresponding to different time points; the perturbation amplitude A refers to the maximum variation amplitude of the periodic sinusoidal perturbation signal, which determines the fluctuation range of the instantaneous air intake flow rate relative to the basic design air volume; the perturbation angular frequency ω refers to a physical quantity that describes the rate of periodic change of the periodic sinusoidal perturbation signal, and its value is related to the period of the perturbation signal, which can be obtained through period conversion.

[0027] Specifically, the basic design airflow is the benchmark airflow rate for maintaining the basic oxygen supply requirements of the aerobic section aeration system in wastewater treatment. It provides the core airflow basis for the instantaneous airflow rate, ensuring the basic oxygen supply for the aerobic section biochemical reactions. The periodic sinusoidal disturbance signal is a signal with a smooth change and stable periodicity. This signal is chosen because it will not cause drastic impact on the aeration system and can apply fluctuations to the flow rate while ensuring process stability. The disturbance amplitude is a parameter that controls the range of flow fluctuations. Its value must ensure that the flow fluctuations are sufficient to deform the soil arch structure of the deposited sludge to reflect its mechanical properties, while not exceeding the operating capacity of the aeration system to avoid affecting the stability of the aerobic section biochemical reactions. The disturbance angular frequency is a parameter that controls the speed of flow fluctuations. It needs to match the response characteristics of the deposited sludge soil arch to ensure that the disturbance signal can effectively act on the deposited sludge layer to capture its mechanical characteristics. The reason for superimposing the basic design air volume with the sinusoidal perturbation signal is that the basic design air volume can maintain the basic oxygen supply requirements of the aerobic section, while the superimposed sinusoidal perturbation signal can, without disrupting the basic oxygen supply, cause the aeration system to generate periodic thrust changes on the deposited sludge layer through periodic small fluctuations in flow rate, thereby exposing the obstruction characteristics of the sludge arch. The instantaneous air intake flow rate obtained by this combination not only meets the basic process requirements of the aerobic section, but also meets the detection requirements of the sludge arch characteristics. Therefore, this method is used to calculate the instantaneous air intake flow rate.

[0028] Specifically, in the actual operation of the aerobic section of wastewater treatment, activated sludge in the dead corners of the guide wall or in areas with low flow velocity at the bottom will deposit on the surface of the aerator, forming a micro-arch structure with yield strength. This structure causes the air path of the aeration system to be reconfigured, and the gas cannot permeate evenly in the form of microbubbles, but instead merges into large-pore channels, thus forming a high-pressure, high-volume, low-dissolved-oxygen condition. At this time, the conventional control logic based on a fixed air volume fails because it assumes a linear relationship between air supply and oxygen mass transfer. The process setting parameters are the benchmark for maintaining basic biochemical reactions in the aerobic section. Calculating the instantaneous airflow based on these parameters can ensure the basic oxygen supply needs of the aerobic section to support the activity of nitrifying bacteria, and can also expose the mechanical properties of the sludge-deposited arch structure through the periodic fluctuations of the flow rate, thereby identifying the actual state of air path reconfiguration, avoiding misjudgments of oxygen mass transfer efficiency by conventional models, and thus accurately adapting to the actual dissolved oxygen requirements of the aerobic section, while reducing energy waste and process operation failures caused by unreasonable air volume.

[0029] In embodiments of the present invention, the calculation of the soil arching ineffective work based on the instantaneous air intake flow rate and the instantaneous pressure of the aeration network in the aerobic section includes: The instantaneous pressure of the aeration pipeline network in the aerobic section is collected, and the instantaneous pressure and instantaneous air intake flow are synchronized in time. Specifically, a pressure sampling point must first be selected at a branch pipe location near the aerator in the aeration network. This location must reflect the actual changes in gas pressure within the aeration system. Then, a pressure sensor is installed at this sampling point, and its zero-point and range calibrations are performed to ensure its range matches the normal pressure range of the aeration network. Simultaneously, an instantaneous airflow acquisition device is activated, and both the pressure sensor and the acquisition device are connected to the same time synchronization module. Both are set to the same sampling frequency, which must meet real-time requirements and not be lower than a preset process acquisition frequency threshold. After completing the above configuration, the pressure sensor and the instantaneous airflow acquisition device are activated, triggering data acquisition at the same time point. Each time instantaneous airflow data is acquired, the corresponding aeration network pressure data is simultaneously recorded. This operation is continuously executed to obtain multiple sets of time-corresponding instantaneous pressure and instantaneous airflow data.

[0030] The disturbance angular frequency is periodically converted to obtain the disturbance period; Specifically, the pre-set disturbance angular frequency value must first be retrieved. This value is determined based on the response characteristics of the deposited sludge arch. Then, using the conversion relationship between period and angular frequency, the disturbance angular frequency is calculated by dividing twice the value of pi by the disturbance angular frequency to obtain the corresponding time length value. After obtaining this value, it is checked whether it falls within the preset process disturbance period range. If it does, the time length value is the disturbance period; if it does not, the pre-set disturbance angular frequency value is adjusted, and the above conversion and checking operations are repeated until the obtained time length value meets the process disturbance period requirements.

[0031] Specifically, the concentration of activated sludge and the thickness of the deposited sludge layer at the bottom of the aerobic section of the wastewater treatment plant are first obtained by using an online sludge concentration detector and an ultrasonic sludge level meter. The sludge yield stress is determined by rheological testing. At the same time, system physical parameters such as the elastic modulus of the aerator membrane, the length and diameter of the aeration pipeline, the inner wall roughness, and the design water depth are collected. Based on the dynamic response characteristics of the soil arching effect, the initial frequency range is determined. This range should avoid the high-frequency range that may cause sludge flocs to break or nitrifying bacteria biofilm to detach, and should not be lower than the low-frequency threshold that cannot cause elastic deformation of the soil arch. Subsequently, a simulation test device consistent with the actual aerobic section operating conditions was built. Multiple gradient angular frequency candidate values ​​were selected within the initial frequency range. The periodic disturbance signals corresponding to each candidate value were superimposed onto the basic design air volume. The pressure fluctuation curve of the aeration pipe network, the displacement change of the deposited sludge layer, and the dissolved oxygen transfer efficiency were monitored simultaneously under each candidate value. The angular frequency range that could cause stable elastic deformation of the soil arch structure and have significant pressure-flow loop area characteristics was screened out. Then, combined with the adjustment response capability of the aeration blower, candidate values ​​that exceeded the frequency conversion range of the blower were eliminated. The repeatability and stability of the remaining candidate values ​​were verified through multiple sets of parallel tests. Finally, the value that could effectively expose the soil arch's hindrance characteristics without affecting the stability of the aerobic section's biochemical reaction was determined as the pre-set disturbance angular frequency.

[0032] The ineffective work of soil arching is calculated based on the disturbance period, instantaneous pressure, and instantaneous air intake flow rate. The formula for calculating the ineffective work of soil arching is as follows: In the formula, It is an ineffective function of soil arching obstruction. It is the disturbance period. It is the instantaneous intake flow rate at time t. It is the instantaneous pressure at time t.

[0033] Specifically, the instantaneous pressure of the aerobic section aeration network refers to the pressure of the gas inside the aerobic section aeration pipeline system of wastewater treatment at a specific moment. It reflects the pressure state of the gas inside the pipeline at that moment and must be consistent with the instantaneous airflow rate in the time dimension to ensure the validity of the corresponding data. The disturbance angular frequency refers to the physical quantity used to describe the rate of change of the periodic disturbance signal. Its value determines the speed of the periodic change of the disturbance signal. The disturbance period refers to the time length required for the periodic disturbance signal to complete one complete periodic change. It is a time parameter obtained by performing a periodic conversion operation on the disturbance angular frequency, reflecting the periodic characteristics of the disturbance signal. The ineffective work of the soil arching refers to the energy consumed by the aeration system within a disturbance period, which is specifically used to overcome the obstruction effect of the soil arching structure formed by the deposited sludge and does not increase the oxygen mass transfer efficiency. It can intuitively reflect the degree of energy loss of the aeration system by the soil arching structure.

[0034] Specifically, the disturbance period is the time interval within which a periodic disturbance signal completes one full change. Its function is to ensure that the calculation covers the effect of a complete flow fluctuation on the soil arch structure. Instantaneous pressure is the pressure of the gas in the aeration network at a corresponding moment, reflecting the strength of the force required to propel the gas flow within the pipeline and aeration system. The rate of change of instantaneous inlet flow rate is the speed at which the instantaneous inlet flow rate changes over time, corresponding to the rate of change of gas volume over time. The calculation of work follows the product relationship between force and corresponding displacement. For a gas system, the quantification of work is the product of pressure and volume change. Here, multiplying the instantaneous pressure by the rate of change of instantaneous inlet flow rate yields the power used by the gas to propel the flow per unit time. Integrating over the disturbance period gives the work done by the gas within a complete disturbance period. This work is specifically consumed in overcoming the obstruction effect of the soil arch structure formed by deposited sludge and does not effectively increase the oxygen mass transfer efficiency. Therefore, the result obtained through this combined calculation is the ineffective work of soil arch obstruction.

[0035] S2. Calculate the bubble morphology structured loss ratio based on the ineffective work of soil arch resistance; In an embodiment of the present invention, the calculation of the bubble morphology structuring loss ratio based on the ineffective work of soil arching includes: The instantaneous aerodynamic power is obtained by multiplying the instantaneous intake flow rate and instantaneous pressure. The total aerodynamic input power is obtained by integrating the instantaneous aerodynamic power based on the disturbance period. Dividing the ineffective work of soil arch obstruction by the total aerodynamic input work yields the bubble morphology structure loss ratio.

[0036] Specifically, instantaneous aerodynamic power refers to the physical quantity obtained by multiplying the instantaneous airflow rate at a certain moment by the instantaneous pressure at the corresponding moment. It reflects the power level output by the aeration system to the aeration network and aerators at that moment, directly reflecting the energy output state of the aeration system at that time node. Total aerodynamic input work refers to the physical quantity obtained by integrating the instantaneous aerodynamic power at each moment within the disturbance period. It represents the total energy input by the aeration system to the entire aeration system within a complete disturbance period and is an overall quantitative indicator of energy input in the aeration process. Bubble morphology structuring loss ratio refers to the dimensionless parameter obtained by dividing the ineffective work of soil arching by the total aerodynamic input work. It reflects the proportion of the total energy input to the aeration system that is specifically consumed to overcome the soil arching effect of deposited sludge. The higher the value of this proportion, the more obvious the degree of air path reconstruction on the surface of the aerator, and the greater the transformation of bubble morphology from micropores to macropores.

[0037] Specifically, the physical definition of power is the product of the action and the corresponding rate of change. Instantaneous airflow corresponds to the rate of change of gas volume, and instantaneous pressure corresponds to the intensity of the action driving the gas flow. The instantaneous aerodynamic power obtained by multiplying the two is the energy rate output by the aeration system at a certain moment. Total aerodynamic input work is the integral of the instantaneous aerodynamic power within the disturbance period. Its physical essence is the total energy input to the aeration system within a complete disturbance period, representing the total energy input of the aeration process. The ineffective work due to soil arching is the energy used by the aeration system to overcome the obstruction of the soil arching effect of deposited sludge, which belongs to the energy loss that does not have an effective effect on oxygen mass transfer. The structural change of bubble morphology originates from the airway reconstruction caused by soil arching. The energy consumption of this process corresponds to the ineffective work due to soil arching, while the total aerodynamic input work is the total energy input of the aeration system. Dividing the two, the ratio can quantify the proportion of the total energy lost in inducing the structural change of bubble morphology. Therefore, this ratio is the bubble morphology structural loss ratio.

[0038] S3. Determine the inherent structural constants based on the design water depth parameters of the aerobic section of the wastewater treatment and the elastic modulus parameters of the aerator membrane; In embodiments of the present invention, the inherent structural constants are determined based on the design water depth parameters of the aerobic section of wastewater treatment and the elastic modulus parameters of the aerator membrane, including: Obtain the design water depth parameters for the aerobic section of wastewater treatment; Obtain the elastic modulus parameter of the aerator diaphragm; Specifically, the design water depth parameter refers to the vertical depth value of the water body in the aerobic section of the wastewater treatment tank determined during the design stage, which reflects the pressure base formed by the water body in the tank on the aeration system; the elastic modulus parameter of the aerator membrane refers to the ability of the membrane material used in the aerator to resist elastic deformation under stress, which reflects the mechanical properties of the membrane itself.

[0039] Specifically, when obtaining the design water depth parameters for the aerobic section of wastewater treatment, first consult authoritative technical documents such as the engineering construction drawings, process design specifications, or completion acceptance reports corresponding to the aerobic section of wastewater treatment. Extract the vertical depth values ​​of the tank body clearly defined in the design phase from these documents. If the technical documents are missing or the data is unclear, conduct on-site measurements using measurement methods conforming to metallurgical engineering measurement specifications. Select at least five measurement points evenly distributed along the length and width of the tank body. Measure the depth using a calibrated digital echo sounder or telescopic probe under full water conditions. When using the probe, ensure the probe is perpendicular to the tank bottom and the bottom contacts the tank's reference surface. When using the echo sounder, install the transducer in a stable position on the measuring vessel and calibrate the sound velocity. Record the water depth data at each measurement point, remove outliers, and calculate the arithmetic mean of the remaining data as the design water depth parameter. When obtaining the elastic modulus parameters of the aerator diaphragm, first consult the aerator supplier... Obtain the material inspection report or certificate of conformity for the corresponding product manual of the diaphragm, and extract the standard value of elastic modulus provided by the manufacturer. If valid data cannot be obtained from the supplier, select an undamaged and representative diaphragm from the aerator in the aerobic section of the wastewater treatment plant as a sample. Prepare a standard tensile test specimen according to the standard for determining the elastic modulus of metallic materials, ensuring that the surface of the specimen is smooth and free of defects and that the dimensions meet the specifications. Install the specimen on a preheated and calibrated electronic universal testing machine, use a wedge tensile clamp to center and clamp it and eliminate the initial prestress, install a high-precision axial extensometer and zero it, and conduct a tensile test at a preset strain control rate. Record the load and strain data in real time, select at least ten sets of data from the linear segment of the stress-strain curve, and calculate the elastic modulus value by the ratio of stress to strain. After verifying repeatability through three parallel tests, take the average value as the elastic modulus parameter of the aerator diaphragm.

[0040] The hydrostatic pressure impedance component is obtained by multiplying the design water depth parameters with the preset first weighting coefficient. The elastic modulus parameter is multiplied by a preset second weighting coefficient to obtain the diaphragm tension impedance component. Specifically, the design water depth parameter range and aerator diaphragm elastic modulus parameter range for the aerobic section of wastewater treatment were first collected. The design water depth parameters covered the mainstream application range of 5 to 8 meters, and the elastic modulus parameters covered the common material property range of 800 MPa to 1400 MPa. Then, a simulation test device consistent with the actual aerobic section operating conditions was constructed, controlling environmental parameters such as water temperature and water quality to be identical to actual operating conditions. Subsequently, within the aforementioned parameter ranges, 10 different sets of design water depth parameters and 10 different sets of aerator diaphragm elastic modulus parameters were selected and cross-combined to form 100 complete test conditions. For each test condition, the corresponding total impedance of the aeration system was measured using pressure sensors and flow acquisition equipment. This total impedance was calculated as the ratio of pressure loss in the aeration network to the gas flow rate. Finally, the design water depth parameters for all test conditions were... Using the design water depth parameter as the first independent variable, the elastic modulus parameter as the second independent variable, and the measured total impedance as the dependent variable, a multiple linear regression model was constructed. The regression coefficients in the model were solved by minimizing the mean square error, yielding the first regression coefficient corresponding to the design water depth parameter and the second regression coefficient corresponding to the elastic modulus parameter. The two regression coefficients were then normalized so that their sum was 1. The normalized first regression coefficient is the preset first weight coefficient, and the normalized second regression coefficient is the preset second weight coefficient. Finally, 20 test conditions that did not participate in the regression fitting were selected for verification. The design water depth parameter and elastic modulus parameter were substituted into the weight coefficients to calculate the inherent structural constant, which was compared with the measured total impedance to ensure that the calculation error was controlled within 5%. If the error exceeded the range, supplementary test data were added and refitted until the accuracy requirements were met.

[0041] The inherent structural constants are obtained by weighted summation of the hydrostatic pressure impedance component and the diaphragm tension impedance component.

[0042] Specifically, the first weighting coefficient refers to a pre-set value used to quantify the influence of the design water depth parameter on the impedance of the aeration system, matching the correlation between water depth and aeration system impedance; the hydrostatic pressure impedance component refers to the result obtained by multiplying the design water depth parameter with the first weighting coefficient, representing the impedance part formed by the aerobic water depth on the aeration system, reflecting the pressure resistance effect brought by water depth; the second weighting coefficient refers to a pre-set value used to quantify the influence of the membrane elastic modulus parameter on the impedance of the aeration system, matching the correlation between membrane characteristics and aeration system impedance; the membrane tension impedance component refers to the result obtained by multiplying the elastic modulus parameter with the second weighting coefficient, representing the impedance part formed by the tension of the aerator membrane itself on the aeration system, reflecting the resistance effect brought by the mechanical characteristics of the membrane; the inherent structural constant refers to the result obtained by weighted summation of the hydrostatic pressure impedance component and the membrane tension impedance component, representing the inherent impedance level of the aerobic section of wastewater treatment, a parameter reflecting the mechanical characteristics of the system itself.

[0043] Specifically, first, retrieve the specific values ​​of the hydrostatic pressure impedance component obtained by multiplying the designed water depth parameters by a preset first weighting coefficient. Simultaneously, retrieve the specific values ​​of the diaphragm tension impedance component obtained by multiplying the elastic modulus parameter of the aerator diaphragm by a preset second weighting coefficient. Then, verify that the calculation process for both components conforms to the preset procedure, confirming that the designed water depth parameters, aerator diaphragm elastic modulus parameters, and corresponding weighting coefficients are all verified valid data. Next, unify the units of measurement for both components, ensuring that ohms are used as the impedance measurement unit. If there are unit differences, use engineering measurement conversion standards. The components are converted to a consistent unit, and then arithmetic addition is used to sum the two impedance components. Six decimal places are retained during the calculation to ensure accuracy. After the summation is completed, the result is compared with the preset reasonable range of the inherent structural constant. If the result is within the range, the summation result is determined as the final inherent structural constant. If the result exceeds the reasonable range, the calculation process of the hydrostatic pressure impedance component and the diaphragm tension impedance component is checked back, and the application of the parameter value weighting coefficient and unit conversion are verified to check for errors. After correcting the errors, the weighted summation operation is re-executed until the result meets the reasonable range requirements of the inherent structural constant.

[0044] It's important to note that the inherent structure constant here isn't solely for describing water depth or membrane material, but rather to address a core concern of the problem: whether nitrite accumulation pathway indicators are comparable and stable under different aerobic section structural conditions. The design water depth determines the hydrostatic pressure that aeration must overcome, directly affecting the initial conditions for bubble formation and oxygen mass transfer intensity; the membrane elastic modulus determines the aeration orifice opening pressure and airflow uniformity, influencing bubble size and response to sludge deposition disturbances. Combining these two into an inherent structure constant essentially introduces a baseline impedance term, independent of operational status and reflecting only the inherent characteristics of the tank and aerator. This term is used to normalize or constrain the bubble morphology structure loss ratio in subsequent calculations, preventing structural differences from being misjudged as operational anomalies.

[0045] S4. Calculate the nitrite accumulation path coefficient based on the inherent structural constant and the bubble morphology structuring loss ratio; In embodiments of the present invention, the calculation of the nitrite accumulation path coefficient based on the inherent structural constant and the bubble morphology structuring loss ratio includes: The total path deflection impedance is obtained by adding the square of the structured loss ratio of the bubble morphology to the square of the inherent structure constant. The nitrite accumulation path coefficient is obtained by dividing the square of the bubble morphology structured loss ratio by the total path deflection impedance.

[0046] Specifically, the square of the bubble morphology structure loss ratio refers to the value obtained by squaring the bubble morphology structure loss ratio. This value, through exponentiation, strengthens the quantitative impact of the proportion of bubble morphology structure loss on the energy loss of the aeration system, making the extent of this loss more easily reflected in subsequent calculations. The total path deflection impedance is a physical quantity obtained by adding the square of the bubble morphology structure loss ratio to the square of the inherent structural constant. It integrates the impedance caused by changes in bubble morphology structure in the aeration system, as well as the impedance inherent in the system's physical structure. It is a comprehensive quantitative indicator of the combined effect of various impedance factors during aeration. The nitrite accumulation path coefficient is a dimensionless parameter obtained by dividing the square of the bubble morphology structure loss ratio by the total path deflection impedance. It corresponds to the relationship between dissolved oxygen transfer efficiency and aeration impedance in the aerobic stage of wastewater treatment, directly reflecting the trend of nitrite accumulation due to changes in dissolved oxygen conditions. The higher the value of this coefficient, the more significant the tendency for nitrite accumulation in the aerobic stage.

[0047] Specifically, when performing the step of adding the square of the bubble morphology structured loss ratio and the square of the inherent structure constant to obtain the total path deflection impedance, the previously calculated bubble morphology structured loss ratio and inherent structure constant are retrieved first, and the two values ​​are squared respectively. The square of the bubble morphology structured loss ratio is used to strengthen the influence weight of the energy loss caused by gas path reconstruction on the aeration impedance, and the square of the inherent structure constant is used to strengthen the influence weight of the system's own physical structure impedance. Then, the two squared results are arithmetically added to obtain a comprehensive quantitative index that integrates the gas path reconstruction loss impedance and the system's inherent impedance, namely the total path deflection impedance. When performing the step of dividing the square of the bubble morphology structured loss ratio by the total path deflection impedance to obtain the nitrite accumulation path coefficient, the previously obtained square of the bubble morphology structured loss ratio and the total path deflection impedance value are retrieved, and the division operation is performed to obtain the corresponding dimensionless parameter, namely the nitrite accumulation path coefficient. The logic behind these two steps is that the total impedance of the path deflection is an overall impedance index affecting gas flow and dissolved oxygen transfer in the aeration system. It is determined by both the gas path reconstruction loss and the inherent impedance of the system. The square of the bubble morphology structuring loss ratio corresponds to the proportion of the impedance brought about by gas path reconstruction in the total impedance. This proportion is directly related to the degree of decrease in dissolved oxygen transfer efficiency. Insufficient dissolved oxygen will inhibit the activity of nitrifying bacteria and thus promote nitrite accumulation. Therefore, by using the ratio of the square of the bubble morphology structuring loss ratio to the total impedance, the trend of nitrite accumulation can be quantified, thereby realizing the transformation from the aeration impedance index to the nitrite accumulation trend parameter.

[0048] Specifically, in the actual operation of the aerobic section of wastewater treatment, activated sludge in the dead corners of the guide wall or in areas with low flow velocity at the bottom will deposit on the surface of the aerator, forming a micro-arch structure. This structure leads to the reconstruction of the air path, causing a sharp increase in bubble diameter and an exponential decrease in the gas-liquid contact surface area, resulting in a high-pressure, high-volume, low-dissolved-oxygen operating condition. Conventional prediction models based on flow rate or pressure fail because they assume a linear relationship between air supply and oxygen mass transfer. The inherent structural constant is an inherent impedance index of the aerobic section itself, and the bubble morphology structuring loss ratio is the proportion of the total energy of the aeration system used to overcome the obstruction of the arch. Together, they reflect the correlation between the actual impedance state of the aeration system and the dissolved oxygen transfer efficiency. Nitrite accumulation is directly related to the dissolved oxygen level in the aerobic stage. Insufficient dissolved oxygen inhibits the activity of nitrifying bacteria, leading to incomplete nitrification and nitrite accumulation. Therefore, calculating the nitrite accumulation path coefficient based on the inherent structural constant and the bubble morphology structure loss ratio can quantify the impact of aeration system impedance changes on dissolved oxygen transfer, thereby accurately reflecting the trend of nitrite accumulation and providing effective parameter basis for process control in the aerobic stage.

[0049] Specifically, the micro-arch structure refers to the micro-arch-shaped structure formed by the accumulation of deposited activated sludge on the surface of the aerator due to the interlocking friction between particles and its own adhesion characteristics in the dead corner of the guide wall or the area with low flow velocity at the bottom of the aerobic section of the wastewater treatment. This structure relies on the shear strength of the sludge itself to maintain its shape stability and has a certain yield strength. It can resist the initial thrust of the aeration airflow, block the normal permeation of gas, and force the gas to find a path with less resistance on the surface of the aerator to converge and flow. This leads to the reconstruction of the gas path from a uniform micropore state to a concentrated macropore state, ultimately affecting the dissolved oxygen transfer efficiency of the aeration system.

[0050] It's important to note that whether nitrite in the aerobic stage continues to be oxidized to nitrate is essentially limited by local dissolved oxygen and oxygen transfer rate, which in turn is highly dependent on the bubble size / specific surface area and system impedance generated by aeration. The arch-like structure formed by sludge deposition alters the gas escape channels, causing microbubbles to merge into larger bubbles, reducing oxygen mass transfer efficiency. The second step of nitrification (NO2⁻→NO3⁻) becomes more sensitive to dissolved oxygen, thus making nitrite accumulation more likely. The bubble morphology restructuring loss ratio quantifies the energy loss caused by this gas path reconstruction. As for the inherent structural constant, it combines the hydrostatic pressure from water depth with the opening pressure / pore gas emission characteristics from the membrane's elastic modulus to form the system's inherent impedance. This is used to differentiate the impact of the same deposition loss on mass transfer at different pool depths and with different aerator materials; therefore, they are not chemically directly causally related to nitrite accumulation.

[0051] S5. Dynamic feedback calibration of the real-time prediction results of nitrogen conversion pathway based on nitrite accumulation pathway coefficient.

[0052] In embodiments of the present invention, dynamic feedback calibration of the real-time prediction results of nitrogen transformation pathways based on nitrite accumulation pathway coefficients includes: Obtain the design carbon source dosing flow rate for the denitrification process; The corrected carbon source dosing execution flow rate is calculated based on the nitrite accumulation path coefficient and the designed carbon source dosing flow rate. The calculation formula for the corrected carbon source dosing execution flow rate is as follows: In the formula, It is to adjust the carbon source addition execution flow rate. It is about designing the carbon source addition flow rate. It is the nitrite accumulation pathway coefficient.

[0053] Specifically, the design carbon source addition acceleration rate for denitrification refers to the baseline rate at which carbon sources are added to the reaction system, determined during the design phase based on the nitrogen treatment load. This provides an initial rate basis for carbon source addition, ensuring a basic supply of carbon sources needed for denitrifying bacteria to decompose nitrogen. The corrected carbon source addition execution flow rate refers to the actual carbon source addition acceleration rate obtained after adjusting the design carbon source addition acceleration rate based on the nitrite accumulation path coefficient. This rate adapts to the carbon source requirements of the denitrification process under nitrite accumulation conditions, ensuring that the amount of carbon source added matches the nitrogen conversion process.

[0054] Specifically, the design carbon source addition acceleration rate, pre-set based on the conventional nitrogen treatment load for the denitrification process, is first retrieved. Simultaneously, the nitrite accumulation path coefficient, calculated earlier, is obtained; this coefficient is a quantitative parameter reflecting the nitrite accumulation trend in the aerobic stage. Then, the calculation step for the corrected carbon source addition execution flow rate is executed. First, the nitrite accumulation path coefficient is multiplied by 0.4 to obtain the carbon source adjustment range parameter matching the nitrite accumulation level. Then, this range parameter is subtracted from 1 to obtain the correction ratio corresponding to the design carbon source addition acceleration rate. Finally, the design carbon source addition acceleration rate is multiplied by this correction ratio to obtain the corrected carbon source addition execution flow rate. The logic behind this step is that the design of the carbon source addition acceleration rate is the basic addition benchmark for the denitrification process. However, nitrite accumulation will change the form composition of nitrogen, and the amount of carbon source required for nitrite denitrification is lower than that for nitrate. Therefore, the higher the nitrite accumulation path coefficient, the lower the actual amount of carbon source added should be. By combining the nitrite accumulation path coefficient with the fixed coefficient of 0.4, the reasonable reduction range of carbon source can be quantified. Then, by combining it with the design of the carbon source addition acceleration rate, the amount of carbon source added can be adapted to the actual nitrogen form distribution, avoiding excessive waste or insufficient carbon source leading to incomplete denitrification, and ensuring the stable and efficient operation of the denitrification process.

[0055] Specifically, in the denitrification process, nitrate denitrification requires a higher amount of carbon source than nitrite denitrification because nitrite has a higher nitrogen valence state, resulting in less electron transfer during denitrification and consequently lower carbon source consumption. The designed carbon source addition acceleration rate is based on the requirements of conventional all-nitrate denitrification, while the nitrite accumulation path coefficient quantifies the degree of nitrite accumulation in the aerobic stage. The more significant the accumulation, the lower the actual carbon source requirement for denitrification. The formula uses 0.4 multiplied by the nitrite accumulation path coefficient, a fitting coefficient verified through multiple process experiments. Its corresponding magnitude can accurately match the reduction relationship between nitrite accumulation and carbon source requirement, avoiding both waste or secondary water pollution caused by excessive carbon source and incomplete denitrification due to insufficient carbon source. Subtracting the product from 1 yields the correction ratio for the design flow rate. Multiplying this by the design carbon source acceleration rate allows the carbon source acceleration rate to be adjusted to a reasonable level that matches the current nitrite accumulation state, thus achieving precise carbon source addition. This ensures the denitrification efficiency of the denitrification process while effectively controlling carbon source consumption costs.

[0056] Dynamic feedback calibration is performed based on the real-time prediction results of the nitrogen conversion pathway using the modified carbon source addition execution flow rate.

[0057] Specifically, the real-time prediction results of the nitrogen conversion pathway refer to the data obtained by real-time prediction of the process and direction of nitrogen conversion from nitrite and nitrate to nitrogen gas in the denitrification process, which reflects the actual dynamic state of nitrogen conversion; dynamic feedback calibration refers to the real-time adjustment operation of the carbon source addition flow rate based on the real-time prediction results of the nitrogen conversion pathway, which is used to ensure that the carbon source addition rate continuously adapts to the actual needs of nitrogen conversion and ensures the stable and efficient operation of the denitrification process.

[0058] Specifically, historical operational data of the wastewater treatment system over the past year was first collected, including key parameters such as the corrected carbon source addition flow rate, nitrite concentration, nitrate concentration, dissolved oxygen value, pH value, sludge concentration, carbon source type, and addition location under different influent loads. Simultaneously, actual state data of the nitrogen transformation pathway during the corresponding time periods were recorded, covering indicators such as the nitrite-to-nitrate conversion rate, nitrate denitrification rate, and nitrogen generation rate. This dataset was divided into training and validation sets in a 7:3 ratio. After standardizing the data to eliminate dimensional differences, a nitrogen transformation pathway prediction model based on dynamic convolution technology was constructed. The model input layer was set to the aforementioned key parameters. The parameters are presented in a time-series format. The hidden layer uses a dynamic convolution module composed of multiple parallel convolution kernels. An attention subnetwork is introduced to extract global information from the input features, generating dynamic weight coefficients for each convolution kernel. This enables adaptive adjustment of the convolution kernel parameters according to the input data features. The output layer contains multiple key rate indicators for the nitrogen conversion path. Subsequently, an online monitoring system is activated. Multi-dimensional sensors installed at the inlet, reaction zone, and outlet of the denitrification tank collect real-time data on the carbon source addition execution flow rate and corresponding real-time water quality parameters at a sampling period of 1 minute. After data preprocessing to remove outliers, the data is input into the trained dynamic convolution prediction model. The model extracts the temporal features and implicit correlations of parameters through a dynamic convolution module, outputting real-time predictions of nitrogen conversion pathways, including the predicted conversion rates of each nitrogen form and the final denitrification efficiency. Simultaneously, it acquires actual nitrogen form concentration data at the denitrification tank effluent using online monitoring equipment, calculates the root mean square error between the actual nitrogen conversion rate and the predicted results, and sets an error threshold of 5%. If the error does not exceed the threshold, the current corrected carbon source addition flow rate is maintained; if the error exceeds the threshold, a dynamic feedback calibration process is initiated, using a backpropagation algorithm to transmit the error signal back to the dynamic convolution model, synchronously updating the parameters of the attention subnetwork and the weight coefficients of the dynamic convolution kernel. Based on the updated model, the corrected carbon source dosing flow rate adjustment value adapted to the current nitrogen conversion state is recalculated. The operating frequency of the carbon source dosing pump is gradually corrected according to the step adjustment principle to avoid the impact of sudden flow rate changes on process stability. Then, the adjusted data is continuously collected for model input and prediction, and the error calculation and calibration process is repeated. The dynamic convolution model is incrementally trained once per hour, and the newly collected operating data is integrated to optimize the model parameters, ensuring the model's adaptability to water quality load fluctuations. Finally, the corrected carbon source dosing flow rate and nitrogen conversion path are matched in real time, ensuring the denitrification efficiency and carbon source utilization rate of the denitrification process.

[0059] Specifically, the nitrite accumulation pathway describes the formation mechanism and trend in the aerobic stage where, due to obstructed aeration and insufficient dissolved oxygen, the nitrification process stops at the ammonia nitrogen to nitrite stage and fails to completely convert to nitrate. Denitrification, on the other hand, occurs in the anoxic / anaerobic stage and focuses on the fate and removal process of the already generated nitrite or nitrate after its reduction to nitrogen gas. Since they are not in the same reaction stage and have different research objects, they are not directly causally related. However, the amount and form of nitrite accumulated in the aerobic stage will determine the nitrogen composition entering the denitrification stage, thus indirectly affecting the carbon source requirements and control strategies for denitrification.

[0060] Specifically, the nitrite accumulation pathway predicted in this invention is essentially a characterizing parameter for whether nitrification is hindered in the aerobic stage, rather than simply referring to the nitrite concentration in the anoxic stage. Its function is to characterize the degree of shift in nitrogen composition when entering the anoxic stage and to be used to correct subsequent denitrification control. Therefore, the core of this technology still focuses on the identification and prediction of nitrogen conversion pathways in the aerobic stage, with the anoxic stage only participating in feedback regulation as a controlled object.

[0061] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution, characterized in that, Includes the following steps: S1. Calculate the instantaneous air intake flow rate based on the process setting parameters of the aerobic section of the wastewater treatment, and calculate the ineffective work of soil arching based on the instantaneous air intake flow rate and the instantaneous pressure of the aeration pipe network in the aerobic section. S2. Calculate the bubble morphology structured loss ratio based on the ineffective work of soil arch resistance; S3. Determine the inherent structural constants based on the design water depth parameters of the aerobic section of the wastewater treatment and the elastic modulus parameters of the aerator membrane; S4. Calculate the nitrite accumulation path coefficient based on the inherent structural constant and the bubble morphology structuring loss ratio; S5. Dynamic feedback calibration of the real-time prediction results of nitrogen conversion pathway based on nitrite accumulation pathway coefficient.

2. The method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution as described in claim 1, characterized in that, Calculate the instantaneous airflow rate based on the process settings parameters of the aerobic section of wastewater treatment, including: The design air volume is adjusted based on the process parameters of the aerobic section of the wastewater treatment system. The instantaneous intake airflow is obtained by superimposing periodic sinusoidal disturbance signals on the basic design air volume. The formula for calculating the instantaneous intake airflow is as follows: In the formula, It is the instantaneous intake flow rate at time t. It is the basic design air volume. It is the amplitude of the disturbance. It is the angular frequency of the disturbance, and t is the time indicator.

3. The method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution as described in claim 2, characterized in that, The design air volume is adjusted based on the process parameters of the aerobic section of wastewater treatment, including: The concentration of activated sludge at the bottom of the aerobic section of the wastewater treatment plant is collected in real time using an online sludge concentration detector. The thickness of the deposited sludge layer in the aerobic section of wastewater treatment is collected in real time using an ultrasonic sludge level gauge. The activated sludge concentration was nonlinearly fitted and converted based on a pre-acquired database of activated sludge rheological properties to obtain the sludge yield stress value. The critical aerodynamic thrust is obtained by multiplying the thickness of the deposited sludge layer and the sludge yield stress value. Based on the critical aerobic thrust, the historical process design air volume of the aerobic section of the wastewater treatment is corrected by aerobic power matching to obtain the corrected design air volume.

4. The method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution according to claim 2, characterized in that, The ineffective work of soil arching is calculated based on the instantaneous air intake flow rate and the instantaneous pressure of the aeration network in the aerobic section, including: The instantaneous pressure of the aeration pipeline network in the aerobic section is collected, and the instantaneous pressure and instantaneous air intake flow are synchronized in time. The disturbance angular frequency is periodically converted to obtain the disturbance period; The ineffective work of soil arching is calculated based on the disturbance period, instantaneous pressure, and instantaneous air intake flow rate. The formula for calculating the ineffective work of soil arching is as follows: In the formula, It is an ineffective function of soil arching obstruction. It is the disturbance period. It is the instantaneous intake flow rate at time t. It is the instantaneous pressure at time t.

5. The method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution according to claim 1, characterized in that, The calculation of the bubble morphology structured loss ratio based on the ineffective work of soil arching includes: The instantaneous aerodynamic power is obtained by multiplying the instantaneous intake flow rate and instantaneous pressure. The total aerodynamic input power is obtained by integrating the instantaneous aerodynamic power based on the disturbance period. Dividing the ineffective work of soil arch obstruction by the total aerodynamic input work yields the bubble morphology structure loss ratio.

6. The method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution according to claim 1, characterized in that, The inherent structural constants are determined based on the design water depth parameters of the aerobic section of wastewater treatment and the elastic modulus parameters of the aerator membrane, including: Obtain the design water depth parameters for the aerobic section of wastewater treatment; Obtain the elastic modulus parameter of the aerator diaphragm; The hydrostatic pressure impedance component is obtained by multiplying the design water depth parameters with the preset first weighting coefficient. The elastic modulus parameter is multiplied by a preset second weighting coefficient to obtain the diaphragm tension impedance component. The inherent structural constants are obtained by weighted summation of the hydrostatic pressure impedance component and the diaphragm tension impedance component.

7. The method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution according to claim 1, characterized in that, The nitrite accumulation path coefficient is calculated based on the inherent structural constant and the bubble morphology structuring loss ratio, including: The total path deflection impedance is obtained by adding the square of the structured loss ratio of the bubble morphology to the square of the inherent structure constant. The nitrite accumulation path coefficient is obtained by dividing the square of the bubble morphology structured loss ratio by the total path deflection impedance.

8. The method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution according to claim 1, characterized in that, Dynamic feedback calibration of real-time prediction results of nitrogen transformation pathways based on nitrite accumulation pathway coefficients includes: Obtain the design carbon source dosing flow rate for the denitrification process; The carbon source dosing execution flow rate was calculated and corrected based on the nitrite accumulation path coefficient and the designed carbon source dosing flow rate. Dynamic feedback calibration is performed based on the real-time prediction results of the nitrogen conversion pathway using the modified carbon source addition execution flow rate.

9. The method for predicting nitrogen transformation pathways in the aerobic stage of wastewater treatment based on dynamic convolution as described in claim 8, characterized in that, The revised formula for calculating the carbon source dosing flow rate is as follows: In the formula, It is to adjust the carbon source addition execution flow rate. It is about designing the carbon source addition flow rate. It is the nitrite accumulation pathway coefficient.

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