CN-122010301-A - Carbon source adaptive regulation and control method and system for denitrification process of high-nitrogen wastewater

CN122010301ACN 122010301 ACN122010301 ACN 122010301ACN-122010301-A

Abstract

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

Inventors

ZHANG MING
Zhou Diefang
ZHENG YONG
NIU SHIFANG
SONG QING

Assignees

上海明诺环境科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260414

Claims (10)

1. A method for adaptively controlling carbon sources in a denitrification process of high-nitrogen wastewater, which is applied to a multi-stage biochemical denitrification system comprising a first aerobic zone and a second anoxic zone positioned downstream of the first aerobic zone, and is characterized by comprising the following steps: Acquiring a real-time state signal of the second anoxic zone and a related state signal of the first aerobic zone; Extracting the change trend of the real-time state signal as a characteristic parameter, and predicting the electron acceptor load entering the second anoxic zone based on the associated state signal to generate a feedforward load prediction parameter; outputting a trace carbon source pulse sequence adding instruction to the second anoxic zone under the calibration triggering condition; Extracting a system response attenuation rule during continuous pulses based on the characteristic parameters, and inverting the actual carbon source consumption rate in the current environment; If the actual carbon source consumption rate is in a preset safety interval, generating a time attenuation weight coefficient based on a time variable from the calibration completion time, and generating a feedback adjustment parameter based on the current real-time value of the characteristic parameter and a reference value in the calibration; And dynamically calculating and outputting a continuous carbon source adding control signal by integrating the actual carbon source consumption rate, the time attenuation weight coefficient, the feedforward load prediction parameter and the feedback regulation parameter.
2. The method for adaptively controlling carbon sources in a denitrification process of high nitrogen wastewater according to claim 1, wherein the real-time status signal comprises an oxidation-reduction potential and a ph of the second anoxic zone; the associated state signal comprises oxidation-reduction potential, pH value and nitrate concentration of effluent in the first aerobic zone.
3. The method for adaptively adjusting and controlling carbon sources in a denitrification process of high-nitrogen wastewater according to claim 2, wherein the step of extracting the change trend of the real-time status signal as a characteristic parameter further comprises: setting a sliding time window; continuously collecting real-time measurement values of the oxidation-reduction potential and the pH value of the second anoxic zone according to a preset sampling frequency in the sliding time window; and respectively obtaining the instantaneous falling slope of the oxidation-reduction potential and the instantaneous rising slope of the PH value as the characteristic parameters by calculating the difference between the measured value at the current moment and the measured value at the starting moment of the sliding time window and dividing the difference by the length of the sliding time window.
4. The method for adaptively controlling carbon sources in a denitrification process of high nitrogen wastewater according to claim 1, wherein the step of generating the feedforward load prediction parameter further comprises: calculating the real-time nitrate nitrogen load of the first aerobic zone at the current moment; An exponential smoothing algorithm is adopted to predict an electron acceptor load predicted value which enters the second anoxic zone after the hydraulic delay time; And generating the feedforward load prediction parameter based on the ratio of the electron acceptor load predicted value to a standard electron acceptor load reference value under the system design working condition.
5. The method for adaptively controlling carbon sources in a denitrification process of high nitrogen wastewater according to claim 1, wherein the step of inverting the actual carbon source consumption rate in the current environment further comprises: extracting a potential total amplitude reduction data set corresponding to continuous multiple pulses, and fitting to obtain an attenuation coefficient; and reversely pushing out the actual carbon source consumption rate by combining the attenuation coefficient, the total mass of the carbon source added by 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 whole pulse sequence.
6. The method for adaptively controlling carbon sources in a denitrification process of high nitrogen wastewater according to claim 1, wherein the step of generating the time-decay weight coefficient further comprises: Recording the time point at which the addition of the trace carbon source pulse sequence is finished and the actual carbon source consumption rate is calculated and output as the self-calibration finishing moment; Calculating an absolute time difference value between the current time and the self-calibration completion time to obtain a continuously increasing time variable; introducing an exponential decay function which monotonically decreases along with time, and generating the time decay weight coefficient by combining a preset decay aging constant.
7. The method for adaptively controlling carbon sources in a denitrification process of high nitrogen wastewater according to claim 1, wherein the step of generating the feedback adjustment parameter further comprises: At the self-calibration completion time, recording the absolute value of the instantaneous oxidation-reduction potential falling slope at the time as a calibration reference value, and recording the instantaneous rising slope of the PH value as a PH value reference value; Continuously extracting the absolute value of the instantaneous falling slope of the oxidation-reduction potential at the current moment as a current ORP real-time value, and extracting the instantaneous rising slope of the pH value at the current moment as a current pH real-time value in continuous operation; And calculating the relative deviation between the current ORP real-time value and the calibration reference value, and dynamically adjusting a proportional gain coefficient based on the consistency judgment of the current pH real-time value and the pH value reference value, wherein the conventional proportional gain coefficient is given when the current pH real-time value accords with the current ORP real-time value change trend, and the proportional gain coefficient is reduced when the current pH real-time value and the current ORP real-time value change trend deviate from each other, so as to generate the final feedback adjustment parameter.
8. The method for adaptively controlling carbon sources in a denitrification process of high nitrogen wastewater according to claim 1, wherein the step of dynamically calculating and outputting a continuous carbon source addition control signal further comprises: Calculating continuous carbon source adding mass flow 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 attenuation weight coefficient and the feedback regulation parameter; Converting the continuous carbon source adding mass flow into a control instruction of a dosing pump, and further generating a continuous carbon source adding control signal; And when the time attenuation weight coefficient is attenuated to a preset lower limit threshold value, the next trace carbon source pulse calibration is forcedly triggered.
9. A high nitrogen wastewater denitrification process carbon source adaptive regulation system for implementing the method of any one of claims 1-8, comprising: the signal acquisition module is used for acquiring a real-time state signal of the second anoxic zone and an associated state signal of the first aerobic zone; the feedforward prediction module is used for extracting the change trend of the real-time state signal as a characteristic parameter, predicting the electron acceptor load entering the second anoxic zone based on the associated state signal, and generating a feedforward load prediction parameter; The pulse calibration module is used for outputting a trace carbon source pulse sequence adding instruction under a calibration triggering condition; The rate inversion module is used for extracting a biochemical response attenuation rule during continuous pulses based on the characteristic parameters and inverting the actual carbon source consumption rate in the current environment; The dynamic feedback module is used for generating a time attenuation weight coefficient based on a time variable from the calibration completion moment if the actual carbon source consumption rate is in a preset safety interval, and generating a feedback adjustment parameter based on the current real-time value of the characteristic parameter and a reference value in the calibration; And the comprehensive control module is used for integrating the actual carbon source consumption rate, the time attenuation weight coefficient, the feedforward load prediction parameter and the feedback regulation parameter, and dynamically calculating and outputting a continuous carbon source addition control signal.
10. The system of claim 9, wherein the integrated control module is further configured to calculate a continuous carbon source dosing mass flow rate at a current time based on the actual carbon source consumption rate, the effective physical volume of the second anoxic zone, the feedforward load prediction parameter, the time attenuation weight coefficient, and the feedback adjustment parameter, convert the continuous carbon source dosing mass flow rate into a control command of a dosing pump, and further generate the continuous carbon source dosing control signal, and when the time attenuation weight coefficient is attenuated to a preset lower threshold, forcibly trigger the pulse calibration module to perform next micro-dose carbon source pulse calibration.

Description

Carbon source adaptive regulation and control method and system for denitrification process of high-nitrogen wastewater Technical Field The invention relates to the technical field of wastewater treatment, in particular to a carbon source adaptive regulation and control method and system in a denitrification process of high-nitrogen wastewater. Background Denitrification is a key element of biological denitrification of wastewater, and refers to a biochemical process that specific microorganisms gradually reduce nitrate to gaseous nitrogen and release the gaseous nitrogen to the atmosphere under anoxic conditions by taking the nitrate as a final electron acceptor. The process is not only a key path for removing nitrogen in the water body, but also an important mechanism for realizing nitrogen fixation and reversion in the global nitrogen circulation. In modern sewage treatment engineering, the two-stage A/O process is an enhanced upgrade of the traditional anoxic-aerobic biological denitrification technology, and a gradient progressive denitrification structure is constructed by connecting two groups of anoxic-aerobic units in series. The process can construct multiple denitrification guarantees by matching with a reflux mechanism of nitrifying liquid and sludge, and is commonly used in sewage treatment scenes with severe emission standards or large fluctuation of influent ammonia nitrogen. However, due to the sectional synergistic characteristics of the head-tail buckling of the two-stage A/O process, the carbon source adding strategy of the A2 section has the defect of disjointing with the dynamic biochemical requirement of the system, and the method is specifically characterized by comprising the following two aspects: first, most projects use a fixed flow pump based on the design average nitrogen concentration for carbon source dosing. When the nitrogen load of the inflow water is increased, the fixed carbon source addition amount cannot meet the denitrification requirement of the sudden increase of the A2 section, so that nitrate is accumulated and the denitrification efficiency is greatly reduced, otherwise, if manual excessive addition is adopted for preventing the exceeding of the standard, the redundant unutilized carbon source can penetrate through an anoxic zone to enter the O2 section, and the exceeding of the COD of the outflow water and the increase of the medicament cost are directly caused. Second, the denitrification operation of the A2 section is highly dependent on the stable output of the preceding O1 section nitration reaction. During the treatment of high nitrogen wastewater, O1 Duan Yi is subject to nitrification stagnation due to Free Ammonia (FA), free Nitrous Acid (FNA) toxicity inhibition or alkalinity starvation. Once the front reaction is blocked, the A2 segment falls into a nitrate nitrogen-free reducible matrix fault state. At this time, the conventional constant volume dosing or a feedforward control model only depending on the water inflow load cannot dynamically sense the biochemical blockage in the process, and the medicine can be continuously injected according to the theoretical load. The carbon source is directly arranged under the condition of lacking an electron acceptor, so that not only is the ineffective waste of the medicament caused, but also the deep systematic defect caused by the series coupling structure of the two-stage A/O process is caused. Therefore, it is necessary to provide a method and a system for adaptively controlling the carbon source in the denitrification process of high-nitrogen wastewater to solve the above problems. Disclosure of Invention The invention overcomes the defects of the prior art and provides a method and a system for adaptively regulating and controlling carbon sources in the denitrification process of high-nitrogen wastewater. In order to achieve the aim, the technical scheme adopted by the invention is that the carbon source adaptive regulation and control method in the denitrification process of the high-nitrogen wastewater is applied to a multi-stage biochemical denitrification system comprising a first aerobic zone and a second anoxic zone positioned at the downstream of the first aerobic zone, and the method comprises the following steps: Acquiring a real-time state signal of the second anoxic zone and a related state signal of the first aerobic zone; Extracting the change trend of the real-time state signal as a characteristic parameter, and predicting the electron acceptor load entering the second anoxic zone based on the associated state signal to generate a feedforward load prediction parameter; outputting a trace carbon source pulse sequence adding instruction to the second anoxic zone under the calibration triggering condition; Extracting a system response attenuation rule during continuous pulses based on the characteristic parameters, and inverting the actual carbon source consumption rate in the current environment