Carbon source adaptive regulation and control method and system in high-nitrogen wastewater denitrification process

Abstract

The invention discloses a method and a system for adaptively regulating and controlling a carbon source in a denitrification process of high-nitrogen wastewater, and belongs to the technical field of wastewater treatment. According to the method, state signals of a second anoxic zone and a first aerobic zone are obtained, a change trend is extracted as a characteristic parameter, and a feedforward electron acceptor load is predicted. When calibration is triggered, the system outputs trace carbon source pulses, and the actual carbon source consumption rate is inverted. And if the rate is safe, generating a time attenuation weight and a feedback adjustment parameter. And finally, integrating the consumption rate, the time weight and the feedforward and feedback parameters, and dynamically outputting a carbon source feeding control signal. Through multi-variable cooperative regulation and control, the defect of weak impact resistance in the traditional process is effectively overcome, and the risks of blind addition and secondary pollution when the system is abnormal are avoided.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to an adaptive control method and system for carbon source in the denitrification process of high-nitrogen wastewater. Background Technology

[0002] Denitrification is the core step in biological nitrogen removal from wastewater. It refers to the biochemical process under anoxic conditions in which specific microorganisms use nitrate as the final electron acceptor to gradually reduce it to gaseous nitrogen and release it into the atmosphere. This process is not only a key pathway for nitrogen removal from water bodies, but also an important mechanism for achieving nitrogen fixation and return in the global nitrogen cycle.

[0003] In modern wastewater treatment engineering, the two-stage A / O process is an enhanced upgrade of the traditional anoxic-aerobic biological nitrogen removal technology. By connecting two sets of anoxic-aerobic units in series, a gradient-progressive nitrogen removal structure is constructed. Combined with the return mechanism of nitrification liquor and sludge, this process can create multiple nitrogen removal safeguards and is often used in wastewater treatment scenarios with stringent discharge standards or large fluctuations in influent ammonia nitrogen. However, the interlocking, synergistic characteristics of the two-stage A / O process lead to a disconnect between the carbon source addition strategy in the A2 stage and the dynamic biochemical requirements of the system, specifically manifested in the following two aspects: First, most projects use fixed-flow pumps based on the design average nitrogen concentration for carbon source addition. When the influent nitrogen load increases, the fixed amount of carbon source added cannot meet the rapidly increasing denitrification demand in the A2 stage, leading to nitrate accumulation and a significant decrease in denitrification efficiency. Conversely, if excessive addition is done manually to prevent exceeding the standard, the redundant unused carbon source will penetrate the anoxic zone and enter the O2 stage, directly causing excessive COD in the effluent and increased reagent costs.

[0004] Secondly, the denitrification operation of the A2 stage is highly dependent on the stable output of the preceding O1 stage nitrification reaction. When treating high-nitrogen wastewater, the O1 stage is susceptible to nitrification stagnation due to the toxicity of free ammonia (FA) and free nitrite (FNA) or alkalinity deficiency. Once the upstream reaction is blocked, the A2 stage will fall into a matrix discontinuity state where no nitrate nitrogen can be reduced. At this time, conventional constant-volume dosing or feedforward control models that rely solely on influent load cannot dynamically detect the biochemical blockage within the process and will continue to inject chemicals according to the theoretical load. This direct discharge of carbon sources in the absence of electron acceptors not only results in ineffective waste of chemicals but also represents a deep-seated systemic defect caused by the series coupling structure of the two-stage A / O process.

[0005] Therefore, it is necessary to provide an adaptive control method and system for carbon source in the denitrification process of high-nitrogen wastewater to solve the above problems. Summary of the Invention

[0006] This invention overcomes the shortcomings of the prior art and provides an adaptive control method and system for carbon source in the denitrification process of high-nitrogen wastewater.

[0007] To achieve the above objectives, the technical solution adopted by this invention is: an adaptive carbon source control method for the denitrification process of high-nitrogen wastewater, wherein the method is applied to a multi-stage biochemical denitrification system including a first aerobic zone and a second anoxic zone located downstream of the first aerobic zone, and the method includes the following steps: Acquire the real-time status signal of the second hypoxic zone and the associated status signal of the first aerobic zone; The changing trend of the real-time state signal is extracted as a feature parameter, and the electron acceptor load entering the second hypoxic zone is predicted based on the associated state signal to generate a feedforward load prediction parameter. Under calibrated triggering conditions, a micro-carbon source pulse sequence delivery command is output to the second anoxic zone; Based on the aforementioned feature parameters, the system response decay law during continuous pulses is extracted, and the actual carbon source consumption rate under the current environment is inverted. If the actual carbon source consumption rate is within a preset safe range, a time decay weight coefficient is generated based on the time variable from the time of calibration completion, and a feedback adjustment parameter is generated based on the current real-time value of the feature parameter and the reference value during calibration. By combining the actual carbon source consumption rate, the time decay weighting coefficient, the feedforward load prediction parameter, and the feedback adjustment parameter, a continuous carbon source addition control signal is dynamically calculated and output.

[0008] In a preferred embodiment of the present invention, the real-time status signal includes the redox potential and pH of the second anoxic zone; The associated state signals include the oxidation-reduction potential, pH, and nitrate concentration in the effluent of the first aerobic zone.

[0009] In a preferred embodiment of the present invention, the step of extracting the changing trend of the real-time state signal as a feature parameter further includes: Set a sliding time window; Within the sliding time window, real-time measurements of the redox potential and pH of the second hypoxic zone are continuously collected at a preset sampling frequency. By calculating the difference between the measured value at the current moment and the measured value at the beginning of the sliding time window, and dividing the difference by the length of the sliding time window, the instantaneous decrease slope of the redox potential and the instantaneous increase slope of the acidity / alkalinity are obtained, respectively, and used as the characteristic parameters.

[0010] In a preferred embodiment of the present invention, the step of generating the feedforward load prediction parameters further includes: Calculate the real-time nitrate nitrogen load in the first aerobic zone at the current moment; The exponential smoothing algorithm was used to predict the electron acceptor load entering the second anoxic zone after a hydraulic delay time. The feedforward load prediction parameter is generated based on the ratio of the predicted electron acceptor load value to the standard electron acceptor load baseline value under the system design conditions.

[0011] In a preferred embodiment of the present invention, the step of reversing the actual carbon source consumption rate under the current environment further includes: Extract the set of total potential drop data corresponding to multiple consecutive pulses, and fit the data to obtain the attenuation coefficient; By combining the attenuation coefficient, the total mass of carbon source added in the pulse sequence, the apparent mass transfer correction coefficient, the effective physical volume of the second anoxic zone, and the total span of all response time windows during the entire pulse sequence, the actual carbon source consumption rate can be deduced.

[0012] In a preferred embodiment of the present invention, the step of generating the time decay weighting coefficient further includes: Record the time point when the micro carbon source pulse sequence is completed and the actual carbon source consumption rate is calculated and output, as the self-calibration completion time; Calculate the absolute time difference between the current time and the self-calibration completion time to obtain a continuously increasing time variable; An exponential decay function that monotonically decreases with time is introduced, and combined with a preset decay time constant, the time decay weighting coefficient is generated.

[0013] In a preferred embodiment of the present invention, the step of generating the feedback adjustment parameter further includes: At the moment of completion of self-calibration, record the absolute value of the instantaneous decrease slope of the redox potential as the calibration reference value, and record the instantaneous increase slope of the acidity as the acidity reference value. During continuous operation, the absolute value of the instantaneous decrease slope of the redox potential at the current moment is continuously extracted as the current real-time ORP value, and the instantaneous increase slope of the acidity / alkalinity at the current moment is extracted as the current real-time pH value. The relative deviation between the current real-time ORP value and the calibration reference value is calculated, and the proportional gain coefficient is dynamically adjusted based on the consistency determination between the current real-time pH value and the acidity / alkalinity reference value: when the current real-time pH value and the current real-time ORP value change trends are consistent, a normal proportional gain coefficient is assigned; when the trends of the two deviate, the proportional gain coefficient is reduced to generate the final feedback adjustment parameter.

[0014] In a preferred embodiment of the present invention, the step of dynamically calculating and outputting a continuous carbon source addition control signal further includes: Based on the actual carbon source consumption rate, the effective physical volume of the second anoxic zone, the feedforward load prediction parameter, the time decay weighting coefficient, and the feedback adjustment parameter, calculate the continuous carbon source addition mass flow rate at the current moment. The continuous carbon source dosing mass flow rate is converted into a control command for the dosing pump, thereby generating the continuous carbon source dosing control signal; Furthermore, when the time decay weighting coefficient decays to a preset lower threshold, the next trace carbon source pulse calibration is forcibly triggered.

[0015] An adaptive carbon source control system for denitrification processes of high-nitrogen wastewater includes: The signal acquisition module is used to acquire the real-time status signal of the second hypoxic zone and the associated status signal of the first aerobic zone; The feedforward prediction module is used to extract the changing trend of the real-time state signal as a feature parameter, and predict the electron acceptor load entering the second hypoxic zone based on the associated state signal to generate feedforward load prediction parameters. The pulse calibration module is used to output a micro-carbon source pulse sequence dosing command under calibration trigger conditions; The rate inversion module is used to extract the biochemical response decay law during continuous pulses based on the feature parameters, and invert the actual carbon source consumption rate under the current environment. The dynamic feedback module is used to generate a time decay weight coefficient based on the time variable calculated from the time of calibration completion if the actual carbon source consumption rate is within a preset safety range, and to generate a feedback adjustment parameter based on the current real-time value of the feature parameter and the reference value during calibration. The integrated control module is used to integrate the actual carbon source consumption rate, the time decay weighting coefficient, the feedforward load prediction parameter, and the feedback adjustment parameter to dynamically calculate and output a continuous carbon source addition control signal.

[0016] In a preferred embodiment of the present invention, the integrated control module is further configured to calculate the current continuous carbon source dosing mass flow rate based on the actual carbon source consumption rate, the effective physical volume of the second anoxic zone, the feedforward load prediction parameter, the time decay weight coefficient, and the feedback adjustment parameter, and convert the continuous carbon source dosing mass flow rate into a control command for the dosing pump, thereby generating the continuous carbon source dosing control signal; and when the time decay weight coefficient decays to a preset lower threshold, the pulse calibration module is forcibly triggered to perform the next micro-dose carbon source pulse calibration.

[0017] This invention addresses the shortcomings of the prior art and has the following beneficial effects: This invention provides a method and system for adaptive carbon source control in the denitrification process of high-nitrogen wastewater. It extracts the changing trends of oxidation-reduction potential and pH as characteristic parameters using a high-frequency differential algorithm, and constructs a multivariate collaborative control architecture that integrates feedforward load prediction and micro-pulse calibration. This establishes a mapping relationship between the generation kinetics of electron acceptors in the upstream aerobic zone and the actual carbon consumption of microorganisms in the downstream anoxic zone, transforming the hydraulically lag- and nonlinear microbial metabolic process into a self-correcting mathematical model. Based on this, the invention can accurately match the electron supply and demand flux across different stages, achieving synergy between carbon source addition and actual biochemical carbon demand. Compared to the traditional static chemical injection mode that treats the biochemical reactor as an isolated physical unit and overly relies on the absolute total nitrogen index of the influent, this invention breaks down the physical isolation between stages. In extreme conditions such as upstream toxicity inhibition leading to nitrification collapse, it can detect and avoid blind addition, preventing the direct discharge of large amounts of unreacted carbon sources due to a lack of free electron acceptors, and eliminating the secondary pollution risk of a sudden increase in effluent chemical oxygen demand.

[0018] This invention continuously acquires measurement values ​​through a sliding time window, calculates the difference between measured values ​​to obtain the instantaneous decrease slope of redox potential and the instantaneous increase slope of pH as characteristic parameters. This method captures the relative evolution rate of the microenvironment driven by substrate degradation, mathematically filtering out fixed measurement biases and eliminating dependence on absolute potential readings from sensors. Existing technologies generally employ feedback control based on absolute measurement thresholds. When faced with harsh high-concentration sludge mixtures, biofilm adhesion easily occurs on the probe surface, causing baseline drift and leading to measurement and control artifacts and dosing failures. The feature extraction method of this invention can still penetrate physical interference and accurately restore the true biochemical metabolic activity within the anoxic zone, even under non-ideal operating conditions with severe sensor contamination, providing disturbance-resistant field benchmark data for multivariate continuous dosing models.

[0019] This invention outputs a micro-carbon source pulse sequence to the reaction zone under calibrated triggering conditions. The total potential decrease is calculated by integrating the instantaneous decline slope of the redox potential during the continuous pulses, and then an exponential decay model is fitted to invert the actual carbon source consumption rate. By applying a chemical substrate perturbation to the biochemical system at a load far lower than the conventional load, a transient metabolic response is forced from the heterotrophic denitrifying bacteria. The gradient decay law of this response intensity is used to quantify the mass transfer resistance and biological background consumption limit at a specific sludge concentration. This allows for the exploration of the true biochemical reaction potential of microorganisms within an extremely low dose boundary without triggering carbon source breakthrough. Traditional exploratory dosing schemes often control the step size too large. When the instantaneous dosing load exceeds the critical point of the maximum specific denitrification rate of the microorganisms, irreversible pollution accidents caused by unreacted substrate overflow are easily induced. The pulse calibration method of this invention obtains a dynamic metabolic baseline with low trial-and-error costs, locks in a safe energy supply upper limit for steady-state dosing, and avoids the risk of microscopic material transformation imbalance.

[0020] This invention calculates real-time nitrate nitrogen load based on nitrate concentration and flow rate in the upstream aerobic zone, introduces an exponential smoothing algorithm with hydraulic delay time to predict electron acceptor load entering the downstream anoxic zone, and generates feedforward load prediction parameters. This prediction mechanism based on hydrodynamic spatiotemporal extrapolation compensates for the time difference in substrate transport between multi-stage series treatment tanks, ensuring that the digital calculation window is synchronized with the spatial trajectory of actual mixed liquor particles. This method empowers downstream actuators to anticipate changes in dissolved reactant flux, enabling pre-resetting of dosage before the arrival of water quality shock waves. Existing technologies often only establish pure time-delay feedback loops for a single anoxic zone, resulting in sluggish system response to sudden increases in influent load and a tendency for insufficient carbon supply to lead to large accumulation of nitrates. The cross-stage feedforward prediction model of this invention enhances the buffering capacity of the biological system to cope with sudden substrate disturbances, ensuring continuous physicochemical balance of electron supply and demand in the denitrification reaction during dynamic evolution. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Figure 1 This is a flowchart of an adaptive carbon source control method for the denitrification process of high-nitrogen wastewater, as described in Example 1. Figure 2 This is a block diagram of a carbon source adaptive control system for a high-nitrogen wastewater denitrification process, as described in Example 2. Figure 3 This is a schematic diagram illustrating the ORP response decay and feature extraction principle under pulsed application of a trace carbon source. Detailed Implementation

[0022] The strongly coupled dynamic evolution characteristics of multi-stage bioreactors in high-nitrogen wastewater treatment systems present a significant contradiction with current isolated, static, or single-feedforward carbon source dosing control logic. Specifically, traditional carbon source dosing systems treat the second anoxic zone as an isolated treatment unit, overly relying on the total nitrogen load of the influent for open-loop control, while neglecting the impact of abrupt changes in the nitrification state of the upstream first aerobic zone (such as nitrification anomalies caused by toxic inhibition) on the downstream electron acceptor (nitrate nitrogen) supply. This lack of cross-stage state awareness leads to the system blindly injecting carbon sources into the second anoxic zone, which is in a reactant (nitrate nitrogen) supply interruption state, even in the event of a cascading failure between upstream and downstream, resulting in severe blind and ineffective dosing and secondary pollution. Furthermore, due to the harsh biochemical environment of high-concentration sludge mixed liquor, sensors are prone to baseline drift, causing absolute value-based feedback control to fail, further reducing the anti-interference capability of the control system. A typical problem that has not yet been solved in the existing technology is how to accurately sense the biochemical synergy status across work sections under harsh working conditions where sensors are susceptible to contamination, and to achieve dynamic tracking of the actual carbon source consumption rate of microorganisms without causing carbon source penetration.

[0023] To address the aforementioned issues, this invention integrates the relative trend extraction of multi-dimensional state signals across different processes with the active detection of trace carbon source pulse sequences. This addresses the problems of precise carbon source dosing in the second anoxic zone and protection against upstream and downstream cascading failures in a two-stage A / O process for high-nitrogen wastewater. This invention abandons reliance on absolute sensor values, introducing a high-frequency differential algorithm to extract the changing trends of oxidation-reduction potential and pH as characteristic parameters, avoiding interference from sensor baseline drift. Furthermore, it constructs a collaborative control architecture combining feedforward load prediction and on-site trace pulse calibration. Through the tentative dosing of trace carbon source pulse sequences, combined with the system response decay law to invert the actual carbon source consumption rate under real biochemical reaction conditions, accurate baseline data is obtained while preventing carbon source penetration. Finally, a comprehensive calculation model including time decay weight coefficients and feedback adjustment parameters is introduced to achieve multi-variable collaborative control of feedforward prediction, real-time feedback, and time decay weights, effectively overcoming the shortcomings of traditional processes such as weak shock resistance, high operating costs, and the risk of secondary pollution.

[0024] 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 embodiments of the present invention, and not all embodiments. 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.

[0025] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein. Therefore, the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0026] Example 1: Figure 1 A flowchart illustrating an adaptive carbon source control method for denitrification of high-nitrogen wastewater according to Embodiment 1 of the present invention is shown. This method is used in a two-stage A / O process for treating high-nitrogen wastewater, specifically for the addition of an external carbon source to the second anoxic zone. Figure 1 As shown, the method includes: S10. Obtain the real-time status signal of the second hypoxic zone and the associated status signal of the first aerobic zone; S20. Extract the changing trend of the real-time state signal as a feature parameter, and predict the electron acceptor load entering the second hypoxic zone based on the associated state signal to generate feedforward load prediction parameters. S30. Under the calibrated triggering conditions, output a micro-carbon source pulse sequence dosing command; S40. Extract the system response decay law during continuous pulses based on feature parameters, and invert the actual carbon source consumption rate under the current environment; S50. If the actual carbon source consumption rate is within the preset safe range, then a time decay weight coefficient is generated based on the time variable from the time of calibration completion, and a feedback adjustment parameter is generated based on the current real-time value of the characteristic parameter and the benchmark value during calibration. S60, taking into account the actual carbon source consumption rate, time decay weighting coefficient, feedforward load prediction parameters, and feedback adjustment parameters, dynamically calculates and outputs a continuous carbon source addition control signal.

[0027] It should be noted that the two-stage A / O process is an enhanced upgrade of the traditional anoxic-aerobic biological nitrogen removal technology. By connecting two sets of "anoxic-aerobic" units in series, a multi-stage series nitrogen removal structure is constructed. In this system, each section has a clear function and works in concert: the first anoxic zone (A1) uses the raw water carbon source for primary denitrification; the first aerobic zone (O1) is responsible for the oxidation and decomposition of major organic matter and ammonia nitrogen nitrification; the second anoxic zone (A2) focuses on the deep denitrification of residual nitrate nitrogen from the previous stage; and the second aerobic zone (O2) is responsible for removing redundant organic matter and further nitrogen removal treatment to ensure the quality of the effluent.

[0028] In this embodiment, the second anoxic zone serves as the core unit of deep denitrification. Its electron acceptor mainly originates from the nitrification process in the first aerobic zone. However, the raw water carbon source often becomes insufficient after primary denitrification in the first anoxic zone, necessitating external carbon source supplementation in the second anoxic zone to achieve efficient conversion of residual nitrate nitrogen. The method in Example 1 adaptively regulates the carbon source addition in the second anoxic zone: S10 acquires the status signal of the second anoxic zone and the correlation signal of the first aerobic zone in real time; S20 predicts the electron acceptor load of the second anoxic zone based on the nitrification load of the first aerobic zone; and S30-S60 dynamically generate carbon source addition commands and optimize them in real time. Combined with the nitrification liquid reflux mechanism, this method effectively solves the problem of carbon source supply and demand imbalance in the second anoxic zone, avoids the excessive waste or incomplete denitrification risks of traditional addition methods, and ensures the efficient and coordinated operation of the multi-stage series denitrification structure, thereby improving carbon source utilization efficiency while ensuring effluent quality.

[0029] In applying the aforementioned method, this embodiment addresses two key challenges: distortion of biochemical signals and lag in microbial response. Given that sensors are susceptible to contamination and baseline drift, relying directly on absolute thresholds can lead to misjudgments in control. Therefore, it is necessary to extract characteristic parameters that do not depend on absolute values ​​to reconstruct the true biochemical reaction environment. Simultaneously, due to the influence of hydraulic retention time and the non-instantaneous nature of metabolism, conventional dosing can easily cause carbon source penetration and excessive effluent chemical oxygen demand (COD). Therefore, it is crucial to accurately invert the actual carbon source consumption rate of microorganisms at extremely low doses without causing contamination. Furthermore, to address the risk of reactant (nitrate nitrogen) supply interruption in the second anoxic zone due to abnormal nitrification in the first aerobic zone, this invention employs upstream and downstream linkage monitoring and safety interlocking mechanisms to proactively activate upstream and downstream interlocking fault protection mechanisms, avoiding blind and ineffective dosing and ensuring stable system operation under complex conditions.

[0030] The implementation of the above method relies on a hardware architecture consisting of a high-precision field sensor array, a programmable logic controller (PLC), and a host computer system with embedded multi-dimensional data processing algorithms. The sensor array is responsible for high-frequency data acquisition across work sections, the PLC executes the underlying pulse timing control and safety interlocking actions, and the host computer system runs the core feature extraction, trend prediction, and dynamic tracking algorithms.

[0031] The steps of the above method will be explained in detail below.

[0032] Step S10: Obtain the real-time status signal of the second hypoxic zone and the associated status signal of the first aerobic zone.

[0033] The second anoxic zone refers to the deep denitrification spatial physical unit located after the first aerobic zone in the two-stage A / O process, which is specifically used to treat residual nitrate nitrogen at the front end; the first aerobic zone refers to the spatial physical unit located upstream of the second anoxic zone, which mainly undertakes the functions of organic matter oxidation and decomposition and ammonia nitrogen nitrification.

[0034] In other words, real-time status signals and related status signals are monitored and extracted in real time by sensor arrays respectively set in the second anoxic zone and the first aerobic zone. Specifically, real-time status signals refer to measured values ​​that can instantaneously reflect the physicochemical environmental characteristics of the current second anoxic zone, specifically oxidation-reduction potential and pH; related status signals refer to measured values ​​in the upstream reaction zone that have a causal coupling relationship with the downstream denitrification process, including oxidation-reduction potential, pH, and effluent nitrate concentration.

[0035] Furthermore, oxidation-reduction potential (ORP) is the numerical value of the macroscopic oxidation-reduction state in the reaction water body. During denitrification, it exhibits a specific decreasing trend as nitrate is consumed. pH is an indicator characterizing the acidity or alkalinity of the water body. Since denitrification produces alkalinity, this indicator tends to increase during the reaction. Effluent nitrate concentration refers to the content of nitrate ions in the mixed liquor after treatment in the first aerobic zone, representing the total amount of electron acceptors that will enter the downstream environment.

[0036] Step S20: Extract the changing trend of the real-time state signal as a feature parameter, and predict the electron acceptor load entering the second hypoxic zone based on the associated state signal to generate feedforward load prediction parameters.

[0037] It should be noted that the trend of change refers to the rate and direction of change of a physical quantity over time, specifically the instantaneous slope obtained by high-frequency differential calculation, which does not depend on the absolute measurement baseline of the sensor; the characteristic parameter refers to the standardized value used for subsequent algorithm model calculation after quantifying the trend of change of the real-time state signal; the electron acceptor load refers to the total mass flux of nitrate and nitrite entering the second anoxic zone with the water flow per unit time.

[0038] Specifically, the method for extracting the changing trend of real-time state signals includes: S211. Set a sliding time window. Preferably, the length of the sliding time window is set to 1 to 5 minutes.

[0039] S212. Within this sliding time window, continuously collect real-time measurements of the oxidation-reduction potential and pH of the second anoxic zone at a preset sampling frequency (e.g., 0.5–2 Hz).

[0040] S213. By calculating the difference between the measured value at the current moment and the measured value at the beginning of the sliding time window, and dividing the difference by the length of the time window, the instantaneous decreasing slope of the redox potential and the instantaneous increasing slope of the acidity / alkalinity are obtained as characteristic parameters.

[0041] The above differential calculation method eliminates the interference of fixed deviation and avoids errors caused by sensor baseline drift.

[0042] Furthermore, the method for generating feedforward load forecasting parameters specifically includes: S221. Calculate the real-time nitrate nitrogen load in the first aerobic zone at the current moment. : ,in, This represents the current wastewater flow rate entering the first aerobic zone. The real-time nitrate concentration was measured in the effluent from the first aerobic zone.

[0043] S222. Considering the time lag effect caused by hydraulic flow, the exponential smoothing algorithm is used to predict the hydraulic delay time. Predicted electron acceptor load after entering the second hypoxic zone : , where α is the smoothing coefficient, with a value range of 0 < α < 1; This is the predicted value of the electron acceptor load from the previous calculation period.

[0044] S223, Generate feedforward load prediction parameters : ;in, This is the standard electron acceptor load reference value under the system design operating conditions. When... A value greater than 1 indicates a risk of shock to the upstream nitration load; when When the value is less than 1, it indicates that the upstream nitrification efficiency has decreased or the influent load has decreased.

[0045] It should be noted that the value of the smoothing coefficient α determines the sensitivity of the prediction model to recent data fluctuations and its ability to resist interference from historical data. In this embodiment, the specific value of α is tuned based on the fluctuation frequency of the effluent water quality in the first aerobic zone and the sensor noise level: when the influent water quality fluctuates drastically and the sensor signal-to-noise ratio is high, α is preferably set to 0.4–0.6 to improve the system's tracking response speed to sudden loads; when the influent water quality is relatively stable or the sensor has high-frequency spike noise, α is preferably set to 0.1–0.3 to enhance the filtering smoothing and anti-interference effects of the algorithm.

[0046] Step S30: Under the calibrated triggering conditions, output a micro-carbon source pulse sequence dosing command.

[0047] It should be noted that the calibration trigger condition refers to the specific logical judgment node that requires reassessment of the system's biochemical reaction capability when the system is in the initial startup phase or has just been released from the abnormal safety interlock state; the trace carbon source pulse sequence dosing instruction refers to the specific control program that controls the dosing pump to intermittently inject carbon source into the second anoxic zone at a very small fixed dose, according to the preset number of times and time intervals.

[0048] In other words, during the initial startup of the system or when the safety interlock is engaged, in order to prevent the carbon source from directly penetrating into the second aerobic zone due to routine trial addition, a preset number of extremely small doses of micropulse carbon source are continuously emitted into the second anoxic zone, with a brief pause period set between adjacent pulses.

[0049] Furthermore, the dosing pump employs a stepper motor-driven diaphragm metering pump with high-frequency response characteristics as the actuating device. It receives digital pulse-width modulation signals from the host computer via industrial Ethernet, enabling the pump to inject a predetermined volume of reagent instantaneously within a very short opening window at its rated maximum stroke, followed by a rapid forced shutdown to zero. The carbon source injected in a single pulse is dynamically calculated based on the effective physical volume of the second anoxic zone and the current total nitrogen load of the influent; this dosage is 1% to 5% of the theoretical hourly requirement for conventional continuous dosing.

[0050] Furthermore, the duration of the brief stagnation period is between 3 and 10 minutes. The lower limit of this stagnation period depends on the complete mixing hydraulic time of the submersible mixer in the second anoxic zone and the minimum response delay of the redox potential sensor, while the upper limit is limited by the endogenous respiration decay cycle of heterotrophic denitrifying bacteria without carbon source supplementation.

[0051] Step S40: Extract the system response decay law during continuous pulses based on feature parameters, and invert the actual carbon source consumption rate under the current environment.

[0052] It should be noted that the continuous pulse period refers to the complete time window from the first micro-dose carbon source pulse to the completion of the last pulse and the complete disappearance of the system's biochemical response.

[0053] Specifically, during the continuous micro-pulse sequence application, multiple consecutive pulse applications are performed. For example... Figure 3 As shown, for each individual pulse application process, the system captures the fluctuation curve of the redox potential (ORP) in real time within its corresponding independent response time window. By integrating the absolute value of the instantaneous decrease slope of the acquired redox potential over time, the total potential decrease induced by a single micropulse can be obtained. ).from Figure 3 It can be intuitively observed that as the number of pulses increases, the biochemical response intensity exhibits a clear exponential gradient decay law, which provides a physical benchmark for the subsequent fitting of the decay coefficient and the accurate inversion of the actual carbon source consumption rate.

[0054] It should be noted that in high-concentration sludge mixed liquor, microorganisms are usually encapsulated by thick extracellular polymeric substances (EPS), resulting in significant mass transfer resistance within the system. This makes it difficult for conventional single-stage carbon source additions to effectively distinguish between the physical mass transfer consumption and the actual biochemical metabolic consumption of the substrate. Therefore, this embodiment employs a continuous micro-pulse sequence addition method. The first micro-pulse is mainly used to overcome the apparent mass transfer resistance of the sludge flocs and fill the dead zones in the flow regime; the resulting potential drop includes a non-metabolic physical hysteresis response. Subsequent micro-pulses directly act on the microenvironment of the microorganisms that have been initially activated.

[0055] Based on this, this method uses exponential curve fitting to the total potential drop set of multiple pulses to obtain the attenuation coefficient, which can filter out the interference of fixed physical mass transfer impedance on biochemical signals at the data processing level. This attenuation coefficient objectively reflects the true substrate affinity boundary of a specific concentration of sludge under the current biochemical environment in a physical sense. The above-mentioned method of combining continuous pulses with attenuation fitting compensates for the measurement and control errors caused by the deviation of high sludge concentration systems from the ideal completely mixed flow state, improving the reliability and accuracy of carbon source consumption rate inversion under harsh operating conditions.

[0056] Furthermore, the decay law of the system response during continuous pulses is extracted, specifically including: S411. Extract the data set of total potential drop corresponding to multiple consecutive pulses, and use the least squares method to perform curve fitting on this data set to obtain a dimensionless attenuation coefficient. Specifically, an exponential decay model is constructed where the total potential decreases with the number of pulses, and its functional relationship is as follows: ,in Let J be the total potential drop of the j-th pulse. This represents the initial total decrease in baseline potential. This is the attenuation coefficient.

[0057] The attenuation coefficient This reflects the exponential decay of subsequent impulse responses compared to the initial baseline response. A higher value indicates a greater scarcity of carbon sources in the second anoxic zone and a higher sensitivity of microorganisms to carbon sources.

[0058] S412, deduce the actual carbon source consumption rate under the current actual reaction conditions in the second anoxic zone. : ;in, The total mass of carbon source added to the pulse sequence; The effective physical volume of the second hypoxic zone; For all response time windows during the entire pulse sequence The total span, i.e. This characterizes the effective cumulative time of microbial participation in the metabolism of these trace carbon sources. The apparent mass transfer correction coefficient is used to compensate for the mass transfer resistance caused by high-concentration sludge mixed liquor, and its value ranges from 0.85 to 0.95. Used to dynamically compensate and correct the base consumption rate based on the transient activity of microorganisms.

[0059] It should be noted that in actual engineering calculations, to ensure dimensional consistency and calculation accuracy, , , It is necessary to substitute engineering units of the same dimension; preferably, when The unit is kilogram (kg). The unit is cubic meters (m³) 3 ), When the unit is hours (h), the actual carbon source consumption rate is calculated. The unit is kilograms per cubic meter per hour (kg / (m²)). 3 ·h)), which directly characterizes the current denitrification capacity per unit volume in the second anoxic zone.

[0060] This invention continuously acquires the total potential drop of each micro-pulse and combines it with the total dosage to invert the actual carbon source consumption rate. This avoids the measurement and control artifacts caused by sensor baseline drift under harsh conditions such as high-concentration sludge, and obtains actual on-site measurement benchmark data that reflects the true biochemical reaction state. Compared with the existing static method of blindly opening the loop for control, this method, with its extremely low trial-and-error cost of micro-pulses, completes the determination of the system potential within a safe range without causing excessive carbon source loss (i.e., penetration), effectively reducing the risk of cascading collapse of upstream and downstream systems.

[0061] In step S50, if the actual carbon source consumption rate is within a preset safe range, a time decay weight coefficient is generated based on the time variable from the time of calibration completion, and a feedback adjustment parameter is generated based on the current real-time value of the characteristic parameter and the benchmark value during calibration.

[0062] Specifically, if the actual carbon source consumption rate calculated in step S40 is within the preset safety range, it indicates that the second anoxic zone has normal denitrification capacity. In this case, the time decay weighting coefficient and feedback adjustment parameter need to be calculated in parallel. It should be noted that the preset safety range refers to the upper and lower threshold ranges of the apparent consumption rate, derived from extensive engineering practice or historical data statistics, that characterizes the normal denitrification activity of microorganisms and the low likelihood of carbon source breakthrough.

[0063] It should be noted that the preset safety range is set based on the limit of the microbial metabolic capacity under specific operating conditions. Specifically, the lower threshold of the safety range is set based on the endogenous respiration denitrification rate of the sludge, that is, the minimum background rate at which microorganisms consume their own endogenous polymers for denitrification without any external carbon source supplementation; the upper threshold of the safety range is set based on the maximum specific denitrification rate of the sludge in the system, that is, the theoretical maximum consumption rate that microorganisms can achieve under ideal, unrestricted conditions where both carbon source and nitrate are absolutely sufficient.

[0064] In practical engineering applications, the specific value of this preset safety range can be obtained in two ways: First, by extracting the actual carbon source consumption rate of the system under conditions where the effluent meets standards and no carbon source breakthrough occurs from the on-site historical operation database, and taking its 95% confidence interval as the safety range; second, by directly calibrating the upper and lower limits of the plant's sludge metabolism through laboratory intermittent respiration measurement tests of biochemical oxygen demand (BOD) and nitrate degradation (such as measuring sludge activity under different carbon-nitrogen ratios). If the calculated actual carbon source consumption rate exceeds this safety range, the system determines that the calibration was interfered with by abnormal operating conditions (such as water toxicity inhibition or serious sensor failure), and will automatically discard the calibration data, maintaining the historical valid data from the previous cycle for safe minimum addition.

[0065] Specifically, the method for generating the time decay weighting coefficient includes: S511. Record the time point when the micro-carbon source pulse sequence is added and the actual carbon source consumption rate is calculated and output in step S30. Define this as the self-calibration completion time.

[0066] S512. Calculate the absolute time difference between the current time and the self-calibration completion time to obtain the continuously increasing time variable. .

[0067] S513. Introduce an exponential decay function that monotonically decreases with time to generate time decay weighting coefficients. : Where k is a preset decay time constant, used to quantify the rate at which the state of a biochemical reaction system undergoes substantial evolution over time. When the unit of measurement is hours (h), the preferred range for the aging decay constant k is 0.1 to 0.5 h. -1 .

[0068] The value of the time decay weight coefficient gradually decreases from its maximum value of 1 at the beginning of calibration to objectively quantify and gradually reduce the system's dependence on historical calibration data.

[0069] Furthermore, the method for generating feedback adjustment parameters includes: S521. At the moment of completion of self-calibration, record the absolute value of the instantaneous decrease slope of the redox potential at that moment, as the ORP reference value during calibration. Simultaneously, record the instantaneous rise rate of pH at that moment as the pH reference value during calibration. .

[0070] S522. During continuous operation, continuously extract the absolute value of the instantaneous decrease slope of the redox potential at the current moment, and use it as the current real-time ORP value. Simultaneously, the instantaneous rise rate of pH at the current moment is continuously extracted as the current real-time pH value. .

[0071] S523. Calculate the relative deviation between the current real-time ORP value and the ORP baseline value, and construct cross-validation weighting coefficients based on the current real-time pH value and the pH baseline value. Combined with the preset proportional gain coefficient, generate a dimensionless feedback regulation parameter that fluctuates around the baseline value of 1. : Constructing dimensionless pH cross-validation weighting coefficients : The weighting coefficient is defined as follows: when the current rate of alkali production (i.e., the slope of pH rise) is higher than or equal to the calibration baseline, the upper limit value of 1 is taken; when the alkali production reaction completely stops or even acidification occurs, i.e. When the value is zero, the lower limit is 0; when the value is between the two, the relative proportion is used. Calculate feedback adjustment parameters ; in, The preset proportional gain coefficient (preferably ranging from 0.1 to 1.0).

[0072] This feedback adjustment parameter is used to dynamically fine-tune the carbon source dosage. In complex biochemical reaction environments, a single change in ORP potential is easily affected by non-denitrifying oxygen-consuming substances in the influent, such as reducing substances like sulfides, resulting in a spurious decrease. Since the reduction of 1g of nitrate nitrogen during denitrification produces approximately 3.57g of alkalinity, it is inevitably accompanied by an increase in pH. This invention introduces the instantaneous pH rise slope for multidimensional cross-validation. When the ORP shows a sharp decrease in slope but the pH slope does not rise synchronously, the algorithm model will determine it as non-denitrification interference, thereby actively reducing the gain weight of the feedback adjustment parameter and avoiding incorrect carbon source dosage due to interference from non-target substrates by a single sensor. This multidimensional data fusion processing enhances the model's resistance to interference from complex high-nitrogen wastewater quality fluctuations.

[0073] Step S60: Based on the actual carbon source consumption rate, time decay weighting coefficient, feedforward load prediction parameters, and feedback adjustment parameters, dynamically calculate and output the continuous carbon source addition control signal.

[0074] Specifically, this step calculates the continuous carbon source addition mass flow rate at the current moment by constructing a multivariate product control model. : ; in, This represents the effective physical volume of the second hypoxic zone.

[0075] To avoid time decay weighting coefficient A control fault occurs when the total dosage approaches zero due to the decreasing time. A lower limit protection method is set: when... When the carbon source decays to a preset lower threshold (preferably 0.6 to 0.8), a new trace carbon source pulse calibration is forcibly triggered (i.e., step S30 is re-executed), thereby updating the actual carbon source consumption rate. And Reset to 1.

[0076] Furthermore, after calculating the mass flow rate... Then, combining the mass concentration and density of the external carbon source reagent used, it is converted into control commands for the dosing pump (such as volumetric flow rate or frequency opening target value), thereby generating a continuous carbon source dosing control signal.

[0077] This step combines kinetic parameters reflecting the metabolic activity of microorganisms (actual carbon source consumption rate and time decay weighting coefficient) with environmental variables reflecting the disturbance state of the macroscopic system (feedforward load prediction parameters and feedback regulation parameters) to calculate the continuous carbon source addition mass flow rate that dynamically matches the actual biochemical carbon demand. This achieves the synergy between the supply of electron acceptors (nitrate nitrogen) across processes and the electron donors (carbon sources) in this process in the spatiotemporal dimension, effectively maintaining the dynamic balance of denitrification electron supply and demand when the complex biochemical system experiences load shocks or upstream anomalies. Compared with existing technologies, this invention abandons the static open-loop control that treats the reaction tank as an isolated black box and relies excessively on the absolute value of the influent. Based on the principles of biochemical reaction kinetics and multivariate control, it transforms the time-lag and nonlinear microbial metabolic process into a mathematical model that can be predicted in advance and self-corrected in a closed loop. This achieves adaptive control of multi-stage series wastewater treatment processes, effectively overcoming the problems of blind and ineffective addition and secondary pollution caused by the unsteady evolution of the system in the treatment of high-nitrogen wastewater.

[0078] Example 2: Figure 2 This is a framework diagram of an adaptive carbon source control system for a high-nitrogen wastewater denitrification process provided in Embodiment 2 of the present invention. Figure 2 As shown, the system includes: The signal acquisition module 210 is used to acquire the real-time status signal of the second hypoxic zone and the associated status signal of the first aerobic zone; The feedforward prediction module 220 is used to extract the changing trend of the real-time state signal as a feature parameter, and predict the electron acceptor load entering the second hypoxic zone based on the associated state signal to generate feedforward load prediction parameters. The pulse calibration module 230 outputs a micro-carbon source pulse sequence dosing command under calibration trigger conditions; The rate inversion module 240 is used to extract the system response decay law during continuous pulses based on feature parameters, and to invert the actual carbon source consumption rate under the current environment. The dynamic feedback module 250 is used to generate a time decay weight coefficient based on the time variable since the calibration completion time if the actual carbon source consumption rate is within the preset safety range, and to generate feedback adjustment parameters based on the current real-time value of the characteristic parameter and the reference value during calibration. The integrated control module 260 is used to dynamically calculate and output a continuous carbon source addition control signal by integrating the actual carbon source consumption rate, time decay weight coefficient, feedforward load prediction parameters, and feedback adjustment parameters.

[0079] Optional, the feedforward prediction module 220 is specifically used for: Set a sliding time window; Within this sliding time window, real-time measurements of the redox potential and pH of the second anoxic zone are continuously collected at a preset sampling frequency. By calculating the difference between the measured value at the current moment and the measured value at the beginning of the sliding time window, and dividing the difference by the length of the time window, the instantaneous decreasing slope of the redox potential and the instantaneous increasing slope of the acidity / alkalinity are obtained as characteristic parameters.

[0080] Optionally, the feedforward prediction module 220 is also used for: Calculate the real-time nitrate nitrogen load in the first aerobic zone at the current moment; Considering the time lag effect caused by hydraulic flow, the exponential smoothing algorithm is used to predict the electron acceptor load after the hydraulic delay time when entering the second anoxic zone. Based on the ratio of the predicted electron acceptor load to the standard electron acceptor load baseline value under the system design conditions, a feedforward load prediction parameter is generated.

[0081] Optional, the rate inversion module 240 is specifically used for: Extract the data set of total potential drop corresponding to multiple consecutive pulses, and use the least squares method to perform curve fitting on the data set to obtain a dimensionless attenuation coefficient. By combining the attenuation coefficient, the total mass of carbon source added in the pulse sequence, the apparent mass transfer correction coefficient, the effective physical volume of the second anoxic zone, and the total span of all response time windows during the entire pulse sequence, the actual carbon source consumption rate under the actual reaction conditions of the current second anoxic zone can be deduced.

[0082] Optional, dynamic feedback module 250, specifically used for: The time point at which the addition of the trace carbon source pulse sequence in the pulse calibration module is completed and the actual carbon source consumption rate is calculated and output is defined as the self-calibration completion time. Calculate the absolute time difference between the current time and the self-calibration completion time to obtain a continuously increasing time variable; An exponential decay function that monotonically decreases with time is introduced, and a time decay weighting coefficient is generated by combining it with a preset decay time constant.

[0083] Optionally, the dynamic feedback module 250 is also used for: At the moment of self-calibration completion, the absolute value of the instantaneous decrease slope of the redox potential at that moment is recorded as the reference value during calibration, and the current real-time value is continuously extracted during continuous operation. Calculate the relative deviation between the current real-time value and the reference value, and combine it with the preset proportional gain coefficient to generate a dimensionless feedback adjustment parameter that fluctuates around the base value 1.

[0084] Optional, the integrated control module 260 is specifically used for: A multivariate product control model is constructed, which is based on the actual carbon source consumption rate, the effective physical volume of the second anoxic zone, the feedforward load prediction parameter, the time decay weight coefficient, and the feedback adjustment parameter, and calculates the continuous carbon source addition mass flow rate at the current moment. By combining the mass concentration and density of the external carbon source reagent used, the continuous carbon source dosing mass flow rate is converted into a control command for the dosing pump, thereby generating a continuous carbon source dosing control signal.

[0085] When the time decay weighting coefficient decays to a preset lower threshold, a new micro-carbon source pulse calibration is forcibly triggered.

[0086] The carbon source adaptive control system for the denitrification process of high-nitrogen wastewater provided in this embodiment of the invention can execute the carbon source adaptive control method for the denitrification process of high-nitrogen wastewater provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method.

[0087] Example 3: This example 3 provides a specific application scenario, as follows: A two-stage A / O process was used to treat high-nitrogen wastewater in the experimental wastewater treatment area, with a designed treatment capacity of [missing information]. =100m3 / h. Effective volume of the second hypoxic zone (Section A2) =500m 3 The external carbon source is a 20% sodium acetate solution.

[0088] Due to long-term operation, the high concentration of sludge in section A2 caused severe membrane fouling of the ORP sensor probe, resulting in a baseline drift of approximately -50mV in the absolute value of the sensor (conventional threshold control has failed under this condition).

[0089] Phase 1: During system startup calibration, three micro-pulses of sodium acetate were continuously injected into section A2 by a stepper diaphragm metering pump. The total dosage was calculated as the pure mass. =2.5kg.

[0090] The system extracts and integrates the instantaneous drop slope of the ORP, and measures the total potential drop of the three pulses as follows: =15.00mV, =10.10mV, =6.80mV.

[0091] The attenuation coefficient was obtained by fitting. ≈0.4. Combining the system's effective volume and impulse response time, the system can infer the current actual carbon source consumption rate. =0.04kg / (m 3 (h). If this value is within the preset safety range, the calibration is successful, and the baseline value of the characteristic parameter is recorded at this time.

[0092] Phase Two: During the stable operation period with normal water intake, feedforward load prediction parameters Maintained at 1.0. Time decay weight. With feedback adjustment parameters In this initial stage, all values ​​are considered to be 1.00.

[0093] The system is based on the formula The calculated basic dosage is approximately 20.0 kg / h. The total nitrogen in the effluent consistently meets the standards, and the COD in the effluent remains at around 25 mg / L (no carbon source breakthrough occurred).

[0094] Phase Three: At a certain point, inhibitory substances were introduced into the raw water, which suppressed the activity of nitrifying bacteria in the first aerobic zone (O1 section). The nitrate concentration in the effluent from the O1 section dropped sharply from 30 mg / L to 5 mg / L within 1 hour.

[0095] The O1 segment sensor keenly detected the sudden drop in nitrate levels, and the feature extraction and feedforward prediction module quickly processed the feedforward load prediction parameters. The value was reduced from 1.0 to 0.167. Simultaneously, due to the interruption of nitrate nitrogen supply to the A2 stage, the A2 stage reaction stalled, and the instantaneous decrease in ORP slope approached 0, triggering feedback regulation of the parameter. Drop down to 0.90. After comprehensive calculation, the system of this invention will add carbon source dosage... The flow rate was instantly reduced from 20 kg / h to 3.01 kg / h (maintaining only basic endogenous metabolism), successfully activating the upstream and downstream cascading failure prevention mechanism.

[0096] If existing technology (relying solely on feedforward open-loop control of influent total nitrogen load) is used, the control system will be completely unable to detect the collapse of the O1 stage since the total influent nitrogen remains unchanged (only the O1 stage fails to nitrify). The dosing pump continues to blindly inject sodium acetate into the A2 stage at a fixed rate of 20 kg / h. Because the A2 stage lacks electron acceptors (nitrate nitrogen), the large amount of added carbon source cannot be consumed and directly penetrates the A2 stage into the final effluent, causing the effluent COD to soar from 25 mg / L to 157.50 mg / L (severely exceeding the standard). This not only results in the ineffective waste of nearly 407.76 kg of sodium acetate per day but also triggers a serious secondary pollution incident.

[0097] Compared to existing open-loop dosing technologies that rely on isolated absolute values ​​and static feedforward loads, this invention offers significantly enhanced protection against misjudgments and shocks. Firstly, its unique micro-dose pulse calibration and trend extraction techniques completely avoid the "monitoring and control artifacts" caused by sensor baseline drift under harsh conditions of high-concentration sludge. This allows for precise acquisition of the most accurate carbon consumption rate baseline of microorganisms without triggering carbon source penetration. More importantly, its multivariate product control system overcomes the physical isolation between processes, achieving second-level coordinated defense across processes by introducing dynamic prediction of feedforward electron acceptors (nitrate nitrogen). In the event of extreme failures such as upstream toxic shocks or nitrification collapse, this invention can instantly cut off blind dosing, eliminating the ineffective waste of hundreds of kilograms of expensive carbon sources daily and fundamentally preventing secondary pollution accidents such as severe COD exceedances caused by the direct discharge of large amounts of unreacted carbon sources into the effluent. This provides a highly robust system-level safety barrier for the deep denitrification process of high-nitrogen wastewater.

[0098] Based on the preferred embodiments of the present invention described above, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A method for adaptive carbon source control in the denitrification process of high-nitrogen wastewater, the method being applied to a multi-stage biological denitrification system comprising a first aerobic zone and a second anoxic zone located downstream of the first aerobic zone, characterized in that, The method includes the following steps: Acquire the real-time status signal of the second hypoxic zone and the associated status signal of the first aerobic zone; The changing trend of the real-time state signal is extracted as a feature parameter, and the electron acceptor load entering the second hypoxic zone is predicted based on the associated state signal to generate a feedforward load prediction parameter. Under the calibrated triggering conditions, a micro-carbon source pulse sequence addition command is output to the second anoxic zone; Based on the aforementioned feature parameters, the system response decay law during continuous pulses is extracted, and the actual carbon source consumption rate under the current environment is inverted. If the actual carbon source consumption rate is within a preset safe range, a time decay weight coefficient is generated based on the time variable from the time of calibration completion, and a feedback adjustment parameter is generated based on the current real-time value of the feature parameter and the reference value during calibration. By combining the actual carbon source consumption rate, the time decay weighting coefficient, the feedforward load prediction parameter, and the feedback adjustment parameter, a continuous carbon source addition control signal is dynamically calculated and output.

2. The adaptive control method for carbon source in the denitrification process of high-nitrogen wastewater according to claim 1, characterized in that, The real-time status signal includes the redox potential and pH of the second hypoxic zone; The associated state signals include the oxidation-reduction potential, pH, and nitrate concentration in the effluent of the first aerobic zone.

3. The adaptive control method for carbon source in the denitrification process of high-nitrogen wastewater according to claim 2, characterized in that, The step of extracting the changing trend of the real-time state signal as a feature parameter further includes: Set a sliding time window; Within the sliding time window, real-time measurements of the redox potential and pH of the second hypoxic zone are continuously collected at a preset sampling frequency. By calculating the difference between the measured value at the current moment and the measured value at the beginning of the sliding time window, and dividing the difference by the length of the sliding time window, the instantaneous decrease slope of the redox potential and the instantaneous increase slope of the acidity / alkalinity are obtained, respectively, and used as the characteristic parameters.

4. The adaptive control method for carbon source in the denitrification process of high-nitrogen wastewater according to claim 1, characterized in that, The step of generating the feedforward load prediction parameters further includes: Calculate the real-time nitrate nitrogen load in the first aerobic zone at the current moment; An exponential smoothing algorithm was used to predict the electron acceptor load entering the second anoxic zone after a hydraulic delay time. The feedforward load prediction parameter is generated based on the ratio of the predicted electron acceptor load value to the standard electron acceptor load baseline value under the system design conditions.

5. The method for adaptive control of carbon source in the denitrification process of high-nitrogen wastewater according to claim 1, characterized in that, The steps for inverting the actual carbon source consumption rate under the current environment further include: Extract the set of total potential drop data corresponding to multiple consecutive pulses, and fit the data to obtain the attenuation coefficient; By combining the attenuation coefficient, the total mass of carbon source added in the pulse sequence, the apparent mass transfer correction coefficient, the effective physical volume of the second anoxic zone, and the total span of all response time windows during the entire pulse sequence, the actual carbon source consumption rate can be deduced.

6. The method for adaptive control of carbon source in the denitrification process of high-nitrogen wastewater according to claim 1, characterized in that, The step of generating the time decay weighting coefficients further includes: Record the time point when the micro carbon source pulse sequence is completed and the actual carbon source consumption rate is calculated and output, as the self-calibration completion time; Calculate the absolute time difference between the current time and the self-calibration completion time to obtain a continuously increasing time variable; An exponential decay function that monotonically decreases with time is introduced, and combined with a preset decay time constant, the time decay weighting coefficient is generated.

7. The adaptive control method for carbon source in the denitrification process of high-nitrogen wastewater according to claim 1, characterized in that, The step of generating the feedback adjustment parameters further includes: At the moment of completion of self-calibration, record the absolute value of the instantaneous decrease slope of the redox potential as the calibration reference value, and record the instantaneous increase slope of the acidity as the acidity reference value. During continuous operation, the absolute value of the instantaneous decrease slope of the redox potential at the current moment is continuously extracted as the current real-time ORP value, and the instantaneous increase slope of the acidity / alkalinity at the current moment is extracted as the current real-time pH value. The relative deviation between the current real-time ORP value and the calibration reference value is calculated, and the proportional gain coefficient is dynamically adjusted based on the consistency determination between the current real-time pH value and the acidity / alkalinity reference value: when the current real-time pH value and the current real-time ORP value change trends are consistent, a normal proportional gain coefficient is assigned; when the trends of the two deviate, the proportional gain coefficient is reduced to generate the final feedback adjustment parameter.

8. The method for adaptive control of carbon source in the denitrification process of high-nitrogen wastewater according to claim 1, characterized in that, The steps of dynamically calculating and outputting the continuous carbon source dosing control signal further include: Based on the actual carbon source consumption rate, the effective physical volume of the second anoxic zone, the feedforward load prediction parameter, the time decay weighting coefficient, and the feedback adjustment parameter, calculate the continuous carbon source addition mass flow rate at the current moment. The continuous carbon source dosing mass flow rate is converted into a control command for the dosing pump, thereby generating the continuous carbon source dosing control signal; Furthermore, when the time decay weight coefficient decays to a preset lower threshold, the next trace carbon source pulse calibration is forcibly triggered.

9. A carbon source adaptive control system for a high-nitrogen wastewater denitrification process, used to implement the method as described in any one of claims 1-8, characterized in that, include: The signal acquisition module is used to acquire the real-time status signal of the second hypoxic zone and the associated status signal of the first aerobic zone; The feedforward prediction module is used to extract the changing trend of the real-time state signal as a feature parameter, and predict the electron acceptor load entering the second hypoxic zone based on the associated state signal to generate feedforward load prediction parameters. The pulse calibration module is used to output a micro-carbon source pulse sequence dosing command under calibration trigger conditions; The rate inversion module is used to extract the biochemical response decay law during continuous pulses based on the feature parameters, and invert the actual carbon source consumption rate under the current environment. The dynamic feedback module is used to generate a time decay weight coefficient based on the time variable calculated from the time of calibration completion if the actual carbon source consumption rate is within a preset safety range, and to generate a feedback adjustment parameter based on the current real-time value of the feature parameter and the reference value during calibration. The integrated control module is used to integrate the actual carbon source consumption rate, the time decay weighting coefficient, the feedforward load prediction parameter, and the feedback adjustment parameter to dynamically calculate and output a continuous carbon source addition control signal.

10. The adaptive carbon source control system for denitrification of high-nitrogen wastewater according to claim 9, characterized in that, The integrated control module is also used to calculate the continuous carbon source addition mass flow rate at the current moment based on the actual carbon source consumption rate, the effective physical volume of the second anoxic zone, the feedforward load prediction parameter, the time decay weight coefficient, and the feedback adjustment parameter, and convert the continuous carbon source addition mass flow rate into a control command for the dosing pump, thereby generating the continuous carbon source addition control signal. Furthermore, when the time decay weighting coefficient decays to a preset lower threshold, the pulse calibration module is forcibly triggered to perform the next micro-dose carbon source pulse calibration.

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