Control method and system of short-cut nitrification and anammox reactor and reactor

Abstract

The application provides a short-range nitrification and anaerobic ammonia oxidation reactor control method and system, and relates to the technical field of wastewater treatment.The application fits nitrite concentration by using obtained load parameters and substrate concentration time series in the short-range nitrification process, calculates the reaction coefficient of the actual generation amount and the target generation amount, adjusts the gas flow of the gas pump, uses the generated nitrite as the substrate of the anaerobic ammonia oxidation reaction, fits the nitrogen concentration, obtains the actual generation amount of nitrogen, calculates the deviation amount, sets a dynamic deviation threshold on the fitting curve of the nitrogen concentration, judges whether the generation amount deviation is over the standard, finally adjusts the load operation parameters according to the feedback result by using a PID control formula, and formulates corresponding adjustment strategies for different reaction stages.The application realizes the dynamic optimization and adjustment of the load operation parameters of the short-range nitrification and anaerobic ammonia oxidation coupled reactor by real-time monitoring and PID control.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, specifically to a control method, system, and reactor for a short-cut nitrification and anaerobic ammonia oxidation reactor. Background Technology

[0002] Short-cut nitrification and anaerobic ammonia oxidation coupled reactors are widely used in the treatment of nitrogen-containing wastewater as a highly efficient nitrogen removal technology. With the continuous increase in nitrogen pollutant emissions from industrial wastewater and municipal sewage, traditional nitrification-denitrification processes suffer from high energy consumption and complex operation. Excessive nitrogen emissions can lead to eutrophication of water bodies, causing algal blooms, affecting water quality, and harming ecosystems. These factors have spurred the growing demand for anaerobic ammonia oxidation technology. However, traditional anaerobic ammonia oxidation reactors typically use fixed loads or manually adjusted operating parameters, such as influent flow rate, stirring rate, and pumping rate. In actual operation, the concentrations of ammonia nitrogen and nitrite in the reactor are prone to dynamic changes due to factors such as fluctuations in influent water quality and changes in microbial activity, resulting in unstable nitrogen removal efficiency. Furthermore, traditional wastewater treatment methods usually remove nitrogen through a coupled process of aerobic nitrification and anaerobic denitrification. However, aerobic reactions require a large supply of oxygen, increasing operating costs. Secondly, the nitrogen removal process is complex, resulting in long treatment cycles. Finally, this traditional nitrogen removal method generates a large amount of sludge, increasing the burden on subsequent treatment processes.

[0003] Existing technologies lack real-time monitoring and intelligent control of the operating status of coupled reactors. Most systems cannot automatically adjust the operating load according to real-time changes in substrate concentration, which can easily lead to fluctuations in treatment effect or increased energy consumption. In addition, traditional adjustment methods have slow response speeds and are difficult to cope with nitrogen conversion processes under complex operating conditions, affecting the continuous and stable operation of the system. Existing anaerobic ammonia oxidation technologies are relatively simple in terms of reaction condition control, making it difficult to achieve stable and efficient nitrogen removal.

[0004] Therefore, it is necessary to provide a control method, system, and reactor for short-cut nitrification and anaerobic ammonia oxidation reactors to solve the aforementioned problems.

[0005] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a control method, system, and reactor for a short-cut nitrification and anaerobic ammonia oxidation reactor, in order to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A control method for a short-cut nitrification and anaerobic ammonium oxidation reactor, comprising the following steps:

[0009] Step 1: Monitor the load operating parameters of the coupled reactor and the reaction substrate concentration at the outlet in real time. Determine the reaction stage of the reactor at the current moment based on the reaction time as the current reaction stage. Extract the time series of load operating parameters and reaction substrate concentration from the start time of the current reaction stage to the current moment. The load operating parameters of the reactor include the water pump inlet flow rate, the agitator rotation speed and the gas pump gas flow rate.

[0010] Step 2: During the short-range nitrification reaction, the nitrite concentration in the current reaction stage is fitted based on the obtained load operation parameter time series and reaction substrate concentration time series. The actual amount of nitrite generated in the current reaction stage is calculated based on the fitted curve. The first reaction coefficient is generated by combining the target amount of nitrite generated in the current reaction stage to adjust the gas flow rate of the gas pump.

[0011] Step 3: Using the nitrite generated by the short-range nitrification reaction as the substrate for the anaerobic ammonium oxidation reaction, the nitrogen concentration during the current reaction time period is fitted based on the obtained nitrite substrate concentration sequence. The actual amount of nitrogen generated during the current time period is obtained based on the nitrogen concentration fitting curve. The nitrogen deviation in each reaction stage is calculated in combination with the expected amount of nitrogen generated in each reaction stage.

[0012] Step 4: Set a dynamic deviation threshold for nitrogen concentration in the fitted curve of nitrogen concentration, and determine whether the deviation value of nitrogen generation in each reaction stage exceeds the dynamic deviation threshold under the current state.

[0013] Step 5: Adjust the load operating parameters using the PID control formula based on the comparison feedback results, and formulate different adjustment strategies for each reaction stage of anaerobic ammonia oxidation.

[0014] Furthermore, the concentration of the reactant at the reactor outlet was monitored in real time, and a time series of the reactant concentration was established. The method used was as follows:

[0015] Sensors were installed at the reactor outlet to measure nitrite concentration. A timer was set, and the total experimental reaction time was divided into three stages based on a preset total experimental duration: a start-up stage, a rapid reaction stage, and a stable operation stage. Data was recorded in timestamp format to form a time series of substrate concentrations. ,in Indicates the first Each sampling measurement time point, Indicates the first Nitrite concentration at each sampling and measurement time point;

[0016] The obtained reaction substrate concentration time series is preprocessed, which includes data cleaning and missing value imputation, using the Z-score statistical method to identify and remove outliers in the reaction substrate concentration time series, and using linear interpolation to imput the original outlier positions and missing positions in the reaction substrate concentration time series. After preprocessing, a complete reaction substrate concentration time series is obtained.

[0017] Furthermore, the nitrite concentration at the current reaction stage is fitted to calculate the first reaction coefficient, which is then used to adjust the gas flow rate of the gas pump. The method used is as follows:

[0018] The expected ammonia nitrogen removal rate was obtained, and the nitrite concentration at the current reaction stage was fitted using the time series of load operating parameters and the time series of reaction substrate concentration, respectively, to obtain the nitrite concentration fitting curve under the preset total reaction time. The formula used is as follows:

[0019] ;

[0020] in, This represents the fitted curve of nitrite concentration. , They represent in time, The concentration of nitrite at time [time]. It is the end point of the startup phase. It is the end point of the rapid response phase. It is the total duration of the experimental reaction, that is, the end point of the steady-state phase. It is a time variable. , These are the reaction rate constants for the nitrite concentrations during the start-up phase and the rapid reaction phase, respectively. The expected ammonia nitrogen removal rate;

[0021] The actual amount of nitrite generated in the current reaction stage is obtained by integrating the fitted curve of nitrite concentration using the following formula:

[0022] ;

[0023] in, These represent the actual amount of nitrite generated during the current reaction stage. Indicates the start time of the current reaction phase. Indicates the end time of the current reaction phase;

[0024] The first reaction coefficient is calculated based on the actual amount of nitrite generated at the current reaction stage, combined with the target amount of nitrite generated. The formula used is as follows:

[0025] ;

[0026] in, Indicates the first reaction coefficient. This indicates the target amount of nitrite generated during the current reaction stage;

[0027] The formula for adjusting the pump gas rate, combined with the first reaction coefficient, is used to adjust the gas flow rate of the pump. The formula is as follows:

[0028] ;

[0029] in, This indicates the adjusted gas flow rate of the air pump. This indicates the current gas flow rate of the air pump. This is an adjustment coefficient used to control the sensitivity of the adjustment. This is the ideal value for the first reaction coefficient.

[0030] Furthermore, the nitrogen concentration during the current reaction period was fitted, and the deviation of nitrogen generation in each reaction stage of the anaerobic ammonia oxidation reaction was calculated. The method used was as follows:

[0031] The nitrogen concentration during the current reaction period was fitted based on the obtained nitrite substrate concentration sequence, using the following formula:

[0032] ;

[0033] in, The fitted curve representing nitrogen concentration. , They represent in time, The concentration of nitrogen at time t. , , These are the reaction rate constants of ammonia nitrogen concentration during the start-up phase, rapid reaction phase, and stable operation phase, respectively.

[0034] The formula used to calculate the actual amount of nitrogen generated in the current time period is:

[0035] ;

[0036] in, This indicates the actual amount of nitrogen generated during the current time period;

[0037] Similarly, the actual nitrogen generation during the start-up phase, rapid response phase, and stable operation phase can be obtained using the above formula. , , The absolute value of the difference between the actual amount of nitrogen produced and the expected amount produced in each stage is the nitrogen deviation. , , .

[0038] Furthermore, a dynamic deviation threshold for nitrogen concentration was set in the fitted curve of nitrogen concentration, based on the following method:

[0039] The anaerobic ammonium oxidation reaction time includes the start-up phase. Rapid response phase and stable operation phase ,in The total experimental reaction run time is denoted as . , For the phased time nodes, the dynamic deviation threshold function is established as follows:

[0040] ;

[0041] in, Indicates the time when the reaction terminates. Falling in The threshold for dynamic deviation of nitrogen concentration within a given time period is: , It is an index for a time period, and ;

[0042] If the dynamic control objective is achieved, then at any time It should meet the following requirements: A piecewise function is used to represent the dynamic deviation threshold of nitrogen concentration:

[0043] ;

[0044] in, This indicates the maximum permissible nitrogen concentration deviation threshold during the startup phase. This indicates the nitrogen concentration deviation threshold during the rapid reaction phase. This represents the threshold for nitrogen concentration deviation during the stable phase.

[0045] Furthermore, based on the comparison feedback results, the load operating parameters are adjusted using a PID control formula. The method used is as follows:

[0046] If the nitrogen deviation in a certain experimental reaction stage exceeds the corresponding dynamic deviation threshold for nitrogen concentration in that stage, the load operating parameters are adjusted using a PID control formula. The formula is as follows:

[0047] ;

[0048] in, This indicates the control scalar values ​​during the current experimental reaction period, including the setpoints for influent flow rate and stirring rate. , , These represent the proportional coefficient, integral coefficient, and differential coefficient, respectively. It is the baseline value of the control scalar for the current experimental reaction time period. This indicates the nitrogen deviation during the current reaction phase. This indicates the time interval from the start of the experiment to the current reaction time. The deviation integral, It represents the derivative of the deviation with respect to time, that is, the instantaneous rate of change of the deviation, which indicates the speed at which the deviation increases or decreases.

[0049] Furthermore, different adjustment strategies were developed for each stage of the experimental reaction, based on the following methods:

[0050] In PID-based dynamic load control, each type of load parameter is regulated by an independent PID controller. It is the water pump inlet flow rate. This refers to the agitator speed. Each load parameter has a safe initial setting reference. The deviation adjustment of the PID output is based on this, plus or minus it. To prevent excessive parameter adjustment from causing system instability, a maximum rate of change and a maximum value range need to be set. The maximum rate of change is: The maximum range of values ​​is: ;

[0051] During different reaction stages, when the nitrogen deviation exceeds the corresponding dynamic deviation threshold, the following measures are taken: , Two load parameters are adjusted separately to achieve dynamic load control for the anaerobic ammonia oxidation process. The logic method for load control is as follows:

[0052] During the startup phase, the PID parameters for the water pump inlet flow rate are adjusted, including reducing the proportional gain. To reduce the impact caused by rapid changes in flow, the integral coefficient is gradually increased. To improve the response to long-term deviations, the differential coefficient is increased. To enhance the suppression of flow rate changes and achieve a slow increase in pump flow rate; the PID parameters of the agitator's stirring rate are adjusted, including reducing the proportional gain. To avoid system disturbances caused by rapid changes in rotational speed, the integral coefficient is gradually increased. To improve the response to uneven mixing, the differential coefficient is increased. To slow down the rate of change of rotation speed, the speed of the agitator is increased slowly;

[0053] During the rapid response phase, the PID parameters for the water pump inlet flow rate are adjusted, including increasing the proportional gain. To enhance the response speed to flow deviations and maintain the integral coefficient To maintain a stable flow rate, the differential coefficient is increased. To avoid flow overshoot and oscillation and achieve rapid response to load fluctuations, the PID parameters of the agitator's stirring rate are adjusted, including increasing the proportional gain. To prevent uneven mixing and maintain the integral coefficient To ensure the stability of stirring, the differential coefficient is increased while keeping it constant. To control the change in stirring rate;

[0054] During the stable operation phase, the PID parameters of the water pump inlet flow rate are adjusted, including reducing the proportional gain. To maintain the current traffic stability, gradually increase the integral coefficient. To eliminate residual bias and reduce differential coefficients Reduce the sensitivity of adjustments and maintain stable flow; adjust the PID parameters of the agitator's stirring rate, including reducing the proportional gain. To ensure a stable stirring rate, gradually increase the integral coefficient. To maintain a uniform reaction and reduce the differential coefficient This reduces sensitivity to changes in rotation speed and ensures stable stirring.

[0055] The present invention also provides a control system for a short-cut nitrification and anaerobic ammonium oxidation reactor, the control system being used to execute the above-described control method for a short-cut nitrification and anaerobic ammonium oxidation reactor, comprising:

[0056] The data acquisition module is used to monitor the load operation parameters of the coupled reactor and the reaction substrate concentration at the outlet in real time. Based on the reaction time, it determines the reaction stage of the reactor at the current moment as the current reaction stage, and extracts the time series of load operation parameters and reaction substrate concentration from the start time of the current reaction stage to the current moment. The load operation parameters of the reactor include the water pump inlet flow rate, the agitator rotation speed, and the gas pump gas flow rate.

[0057] The substrate concentration modeling module is used to fit the nitrite concentration of the current reaction stage in the short-range nitrification process based on the obtained load operation parameter time series and reaction substrate concentration time series. Based on the fitted curve, the actual amount of nitrite generated in the current reaction stage is calculated. Combined with the target amount of nitrite generated in the current reaction stage, the first reaction coefficient is calculated to adjust the gas flow rate of the gas pump.

[0058] The target setting and deviation calculation module uses nitrite generated by short-range nitrification reaction as the substrate for anaerobic ammonium oxidation reaction. In the anaerobic ammonium oxidation reaction, the nitrogen concentration of the current reaction time period is fitted according to the obtained nitrite substrate concentration sequence. Based on the nitrogen concentration fitting curve, the actual amount of nitrogen generated in the current time period is obtained. Combined with the expected amount of nitrogen generated in each reaction stage, the nitrogen deviation in each reaction stage is calculated.

[0059] The dynamic deviation detection module is used to set the dynamic deviation threshold of nitrogen concentration in the fitting curve of nitrogen concentration, and to determine whether the deviation value of nitrogen generation in each reaction stage exceeds the dynamic deviation threshold under the current state.

[0060] The PID control and regulation module is used to adjust the load operating parameters using PID control formulas based on the comparison feedback results, and to formulate different adjustment strategies for each reaction stage of anaerobic ammonia oxidation.

[0061] The present invention also provides a short-cut nitrification and anaerobic ammonium oxidation reactor, the reactor comprising a water pump, a stirrer, and an air pump, wherein the water pump, stirrer, and air pump are controlled by the control method of the above-described short-cut nitrification and anaerobic ammonium oxidation reactor.

[0062] Compared with the prior art, the beneficial effects of the present invention are:

[0063] This invention achieves dynamic monitoring of the reactor's operating status by collecting real-time ammonia nitrogen and nitrite concentrations at the reactor inlet and outlet, and combining this with real-time load operating parameters to form a substrate concentration time series. Furthermore, by combining short-cut nitrification with anaerobic ammonium oxidation, the nitrite generated during short-cut nitrification can be fully utilized as a substrate for ANAMMOX, significantly improving the overall nitrogen removal rate. This invention also reduces the demand for external oxygen, thereby reducing energy consumption and effectively optimizing operating costs.

[0064] This invention adopts a three-stage segmented control strategy consisting of a startup stage, a rapid response stage, and a stable operation stage, and establishes a dynamic deviation threshold to realize a real-time dynamic monitoring and adjustment mechanism. Combined with the established dynamic deviation threshold, the operating status is automatically judged according to the allowable deviation range of different stages, avoiding overreaction caused by blind adjustment. At the same time, the threshold smooth transition design ensures the continuity of the control process and the stability of the system. Attached Figure Description

[0065] Figure 1 This is a schematic diagram of the overall method flow of the present invention.

[0066] Figure 2 This is a schematic diagram of the system module flow of the present invention. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0068] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0069] Example:

[0070] Please see Figure 1 A control method for a short-cut nitrification and anaerobic ammonium oxidation reactor, comprising the following steps:

[0071] Step 1: Monitor the load operating parameters of the coupled reactor and the reaction substrate concentration at the outlet in real time. Determine the reaction stage of the reactor at the current moment based on the reaction time as the current reaction stage. Extract the time series of load operating parameters and reaction substrate concentration from the start time of the current reaction stage to the current moment. The load operating parameters of the reactor include the water pump inlet flow rate, the agitator rotation speed and the gas pump gas flow rate.

[0072] In a specific embodiment of the present invention, a gas flow sensor is installed at the front end of the coupled reactor to monitor the gas flow of the gas pump. The oxygen pumped out by the gas pump is used as dissolved oxygen in the short-range nitrification reaction to react with the ammonia nitrogen substrate to generate nitrite, an intermediate product of the coupled reaction. A nitrite concentration sensor is installed at the outlet of the nitrification device to obtain the nitrite substrate concentration time series. A water flow sensor is installed at the anaerobic ammonia oxidation device in the coupled reactor to monitor the water pump inlet flow. At the same time, a speed sensor is installed to measure the rotation speed of the stirrer. A nitrogen concentration sensor is installed at the outlet of the anaerobic ammonia oxidation device to obtain the nitrogen substrate concentration time series.

[0073] The reaction time is divided into three stages according to the experimental design: the start-up stage, the rapid response stage, and the stable operation stage. By monitoring the timestamps in real time and comparing them with the preset time period, the reaction stage at the current moment can be determined.

[0074] Furthermore, the concentration of the reactant at the reactor outlet was monitored in real time, and a time series of the reactant concentration was established. The method used was as follows:

[0075] Sensors were installed at the reactor outlet to measure nitrite concentration. A timer was set, and the total experimental reaction time was divided into three stages based on a preset total experimental duration: a start-up stage, a rapid reaction stage, and a stable operation stage. Data was recorded in timestamp format to form a time series of substrate concentrations. ,in Indicates the first Each sampling measurement time point, Indicates the first Nitrite concentration at each sampling and measurement time point;

[0076] The obtained reaction substrate concentration time series is preprocessed, which includes data cleaning and missing value imputation, using the Z-score statistical method to identify and remove outliers in the reaction substrate concentration time series, and using linear interpolation to imput the original outlier positions and missing positions in the reaction substrate concentration time series. After preprocessing, a complete reaction substrate concentration time series is obtained.

[0077] Step 2: During the short-range nitration reaction, the nitrite concentration in the current reaction stage is fitted based on the obtained load operation parameter time series and reaction substrate concentration time series. The actual amount of nitrite generated in the current reaction stage is calculated based on the fitted curve. The first reaction coefficient is generated by combining the target amount of nitrite generated in the current reaction stage to adjust the gas flow rate of the gas pump.

[0078] In a specific embodiment of the present invention, by fitting the nitrite concentration based on the acquired load operating parameters and the reaction substrate concentration time series, the dynamic changes of the reaction can be accurately depicted. This not only helps to determine the actual amount of nitrite generated in the current reaction stage, but also allows for comparison with the set target amount of nitrite generated, thereby calculating the first reaction coefficient.

[0079] Furthermore, the nitrite concentration at the current reaction stage is fitted to calculate the first reaction coefficient, which is then used to adjust the gas flow rate of the gas pump. The method used is as follows:

[0080] The expected ammonia nitrogen removal rate was obtained, and the nitrite concentration at the current reaction stage was fitted using the time series of load operating parameters and the time series of reaction substrate concentration, respectively, to obtain the nitrite concentration fitting curve under the preset total reaction time. The formula used is as follows:

[0081] ;

[0082] in, This represents the fitted curve of nitrite concentration. , They represent in time, The concentration of nitrite at time [time]. It is the end point of the startup phase. It is the end point of the rapid response phase. It is the total duration of the experimental reaction, that is, the end point of the steady-state phase. It is a time variable. , These are the reaction rate constants for the nitrite concentrations during the start-up phase and the rapid reaction phase, respectively. The expected ammonia nitrogen removal rate is given. In the formula for the above nitrite concentration fitting curve, the exponential growth model is used in the start-up phase to reflect the gradual increase of concentration, which reflects the adaptation and acceleration process in the early stage of the reaction. In the rapid reaction phase, the reaction is adjusted by exponential decay to reflect the change in reaction rate and the potential depletion effect of reactants. In the stable operation phase, the linear growth model is used to describe the persistence and stability of the reaction.

[0083] The actual amount of nitrite generated in the current reaction stage is obtained by integrating the fitted curve of nitrite concentration using the following formula:

[0084] ;

[0085] in, These represent the actual amount of nitrite generated during the current reaction stage. Indicates the start time of the current reaction phase. Indicates the end time of the current reaction phase;

[0086] The first reaction coefficient is calculated based on the actual amount of nitrite generated at the current reaction stage, combined with the target amount of nitrite generated. The formula used is as follows:

[0087] ;

[0088] in, Indicates the first reaction coefficient. This represents the target amount of nitrite generated in the current reaction stage. The formula above directly reflects the efficiency and stability of the reaction by comparing the actual amount of nitrite generated in the current reaction stage with the target amount. The smaller the value, the closer the reactor's current operating state is to the preset target. A larger value indicates that the actual amount produced in the current reaction stage differs significantly from the target amount.

[0089] The formula for adjusting the pump gas rate, combined with the first reaction coefficient, is used to adjust the gas flow rate of the pump. The formula is as follows:

[0090] ;

[0091] in, This indicates the adjusted gas flow rate of the air pump. This indicates the current gas flow rate of the air pump. This is an adjustment coefficient used to control the sensitivity of the adjustment. This represents the ideal value of the first reaction coefficient; in the above formula, the pump flow rate is adjusted using the current reaction deviation through a feedback mechanism, when... Greater than When the reaction deviates significantly from the ideal state, the pump flow rate will be increased to push the reaction toward the ideal direction; when Less than When this occurs, it indicates that the system is close to its ideal state, which will reduce traffic changes and ensure stable system operation.

[0092] It should be noted that the nitrite obtained through the short-range nitrification reaction will be used entirely as the substrate for the subsequent anaerobic ammonium oxidation reaction. The dissolved oxygen concentration in the short-range nitrification reaction is adjusted by adjusting the gas pump rate, and the gas flow rate of the gas pump is adjusted based on the first reaction coefficient.

[0093] Step 3: Using the nitrite generated by the short-range nitrification reaction as the substrate for the anaerobic ammonium oxidation reaction, the nitrogen concentration during the current reaction time period is fitted based on the obtained nitrite substrate concentration sequence. The actual amount of nitrogen generated during the current time period is obtained based on the nitrogen concentration fitting curve. The nitrogen deviation in each reaction stage is calculated by combining the expected amount of nitrogen generated in each reaction stage.

[0094] In a specific embodiment of the present invention, nitrite generated by short-range nitrification is used as the substrate for anaerobic ammonium oxidation. In the coupled reaction, the deviation in nitrogen production is directly related to the change in nitrite concentration. If the deviation is large, it indicates that the current reaction conditions or substrate utilization efficiency are insufficient, suggesting that the substrate concentration or reaction conditions, such as temperature and pH, need to be adjusted. The results of the two reactions are linked together to form a closed-loop control system, so that the state of each reaction can affect the operation of the other reaction. The overall performance of the coupled reaction is evaluated periodically, including the efficiency of nitrogen production and substrate conversion rate, to ensure that the system operates under optimal conditions.

[0095] Furthermore, the nitrogen concentration during the current reaction period was fitted, and the deviation of nitrogen generation in each reaction stage of the anaerobic ammonia oxidation reaction was calculated. The method used was as follows:

[0096] The nitrogen concentration during the current reaction period was fitted based on the obtained nitrite substrate concentration sequence, using the following formula:

[0097] ;

[0098] in, The fitted curve representing nitrogen concentration. , They represent in time, The concentration of nitrogen at time t. , , These represent the reaction rate constants of ammonia nitrogen concentration during the start-up, rapid reaction, and stable operation phases, respectively. In the formula for the nitrogen concentration fitting curve above, the magnitude of the reaction rate constant is set to... In the initial stage, nitrogen production is slow, so an exponential decay model is used. This stage is characterized by low substrate concentration at the start of the reaction, limiting the reaction rate, and a slow initial increase in nitrogen concentration. After entering the rapid reaction stage, reaction conditions become more favorable, and the nitrogen production rate increases rapidly; therefore, a growth exponential model is used to describe this. This is the maximum reaction rate constant, indicating a rapid increase in nitrogen concentration during this stage. This stage is characterized by a moderate substrate concentration, leading to a significant increase in the reaction rate and a rapid rise in nitrogen concentration. In the steady-state phase, although nitrogen concentration has reached a high level, the reaction gradually stabilizes, and a decrease in nitrogen concentration may occur. This is due to… Due to changes in reaction conditions, such as substrate depletion or the rate of decrease in nitrogen concentration caused by reaction equilibrium, this stage is characterized by the reaction stabilizing, the slowing of nitrogen concentration increase, and even a slight decrease.

[0099] The formula used to calculate the actual amount of nitrogen generated in the current time period is:

[0100] ;

[0101] in, This indicates the actual amount of nitrogen generated during the current time period;

[0102] Similarly, the actual nitrogen generation during the start-up phase, rapid response phase, and stable operation phase can be obtained using the above formula. , , The absolute value of the difference between the actual amount of nitrogen produced and the expected amount produced in each stage is the nitrogen deviation. , , .

[0103] Step 4: Set a dynamic deviation threshold for nitrogen concentration in the fitted curve of nitrogen concentration, and determine whether the deviation value of nitrogen generation in each reaction stage exceeds the dynamic deviation threshold under the current state.

[0104] In a specific embodiment of the present invention, setting a dynamic deviation threshold for nitrogen concentration can provide a standard for real-time monitoring of the reaction process. Since the nitrogen generated in different reaction stages is different, setting respective deviation thresholds can adjust the reaction conditions for different reaction characteristics.

[0105] Furthermore, a dynamic deviation threshold for nitrogen concentration was set in the fitted curve of nitrogen concentration, based on the following method:

[0106] The anaerobic ammonium oxidation reaction time includes the start-up phase. Rapid response phase and stable operation phase ,in The total experimental reaction run time is denoted as . , For the phased time nodes, the dynamic deviation threshold function is established as follows:

[0107] ;

[0108] in, Indicates the time when the reaction terminates. Falling in The threshold for dynamic deviation of nitrogen concentration within a given time period is: , It is an index for a time period, and ;

[0109] If the dynamic control objective is achieved, then at any time It should meet the following requirements: A piecewise function is used to represent the dynamic deviation threshold of nitrogen concentration:

[0110] ;

[0111] in, This indicates the maximum permissible nitrogen concentration deviation threshold during the startup phase. This indicates the nitrogen concentration deviation threshold during the rapid reaction phase. This represents the nitrogen concentration deviation threshold during the stable phase. In the formula above representing the dynamic deviation threshold of nitrogen concentration, the reaction rate is slow during the start-up phase, and the amount of nitrogen generated is limited, so a threshold is set. The maximum permissible nitrogen concentration deviation is small, reflecting the requirement for high sensitivity in the initial stage of the reaction; in the rapid reaction stage, the nitrogen generation rate increases significantly, and the set dynamic threshold is [value missing]. This reflects that during this stage, the allowable deviation of nitrogen concentration increases linearly over time, adapting to the accelerated reaction rate; in the stable operation stage, the reaction tends to stabilize, and the change in nitrogen production decreases, at which point the dynamic threshold is set to... The allowable deviation range has been further expanded, reflecting the stability of the reaction. The linear growth method refines the monitoring during the stable phase and improves the ability to manage nitrogen concentration.

[0112] Step 5: Adjust the load operating parameters using the PID control formula based on the comparison feedback results, and formulate different adjustment strategies for each reaction stage of anaerobic ammonia oxidation.

[0113] In a specific embodiment of the present invention, by formulating adjustment strategies for different reaction stages, the optimal performance of the system during startup, rapid response, and stable operation is ensured. This method not only improves the accuracy of nitrogen concentration control but also guarantees the stability and safety of the system, avoiding potential risks caused by excessive adjustment. At the same time, through independent PID control of the water pump inlet flow rate and the agitator speed, it can flexibly respond to different load changes and achieve dynamic load optimization of the anaerobic ammonia oxidation process. This control strategy provides a scientific and reliable solution for the management of complex reaction systems, greatly improving the efficiency and safety of experimental and industrial applications.

[0114] Furthermore, based on the comparison feedback results, the load operating parameters are adjusted using a PID control formula. The method used is as follows:

[0115] If the nitrogen deviation in a certain experimental reaction stage exceeds the corresponding dynamic deviation threshold for nitrogen concentration in that stage, the load operating parameters are adjusted using a PID control formula. The formula is as follows:

[0116] ;

[0117] in, This indicates the control scalar values ​​during the current experimental reaction period, including the setpoints for influent flow rate and stirring rate. , , These represent the proportional coefficient, integral coefficient, and differential coefficient, respectively. It is the baseline value of the control scalar for the current experimental reaction time period. This indicates the nitrogen deviation during the current reaction phase. This indicates the time interval from the start of the experiment to the current reaction time. The deviation integral, It represents the derivative of the deviation with respect to time, that is, the instantaneous rate of change of the deviation, which indicates the speed at which the deviation increases or decreases.

[0118] Furthermore, different adjustment strategies were developed for each stage of the experimental reaction, based on the following methods:

[0119] In PID-based dynamic load control, each type of load parameter is regulated by an independent PID controller. It is the water pump inlet flow rate. This refers to the agitator speed. Each load parameter has a safe initial setting reference. The deviation adjustment of the PID output is based on this, plus or minus it. To prevent excessive parameter adjustment from causing system instability, a maximum rate of change and a maximum value range need to be set. The maximum rate of change is: The maximum range of values ​​is: ;

[0120] During different reaction stages, when the nitrogen deviation exceeds the corresponding dynamic deviation threshold, the following measures are taken: , Two load parameters are adjusted separately to achieve dynamic load control for the anaerobic ammonia oxidation process. The logic method for load control is as follows:

[0121] During the startup phase, the PID parameters for the water pump inlet flow rate are adjusted, including reducing the proportional gain. To reduce the impact caused by rapid changes in flow, the integral coefficient is gradually increased. To improve the response to long-term deviations, the differential coefficient is increased. To enhance the suppression of flow rate changes and achieve a slow increase in pump flow rate; the PID parameters of the agitator's stirring rate are adjusted, including reducing the proportional gain. To avoid system disturbances caused by rapid changes in rotational speed, the integral coefficient is gradually increased. To improve the response to uneven mixing, the differential coefficient is increased. To slow down the rate of change of rotation speed, the speed of the agitator is increased slowly;

[0122] During the rapid response phase, the PID parameters for the water pump inlet flow rate are adjusted, including increasing the proportional gain. To enhance the response speed to flow deviations and maintain the integral coefficient To maintain a stable flow rate, the differential coefficient is increased. To avoid flow overshoot and oscillation and achieve rapid response to load fluctuations, the PID parameters of the agitator's stirring rate are adjusted, including increasing the proportional gain. To prevent uneven mixing and maintain the integral coefficient To ensure the stability of stirring, the differential coefficient is increased while keeping it constant. To control the change in stirring rate;

[0123] During the stable operation phase, the PID parameters of the water pump inlet flow rate are adjusted, including reducing the proportional gain. To maintain the current traffic stability, gradually increase the integral coefficient. To eliminate residual bias and reduce differential coefficients Reduce the sensitivity of adjustments and maintain stable flow; adjust the PID parameters of the agitator's stirring rate, including reducing the proportional gain. To ensure a stable stirring rate, gradually increase the integral coefficient. To maintain a uniform reaction and reduce the differential coefficient This reduces sensitivity to changes in rotation speed and ensures stable stirring.

[0124] Please see Figure 2 The present invention also provides a control system for a short-cut nitrification and anaerobic ammonium oxidation reactor, the control system being used to execute the above-described control method for a short-cut nitrification and anaerobic ammonium oxidation reactor, comprising:

[0125] The data acquisition module is used to monitor the load operation parameters of the coupled reactor and the reaction substrate concentration at the outlet in real time. Based on the reaction time, it determines the reaction stage of the reactor at the current moment as the current reaction stage, and extracts the time series of load operation parameters and reaction substrate concentration from the start time of the current reaction stage to the current moment. The load operation parameters of the reactor include the water pump inlet flow rate, the agitator rotation speed, and the gas pump gas flow rate.

[0126] The substrate concentration modeling module is used to fit the nitrite concentration of the current reaction stage in the short-range nitrification process based on the obtained load operation parameter time series and reaction substrate concentration time series. Based on the fitted curve, the actual amount of nitrite generated in the current reaction stage is calculated. Combined with the target amount of nitrite generated in the current reaction stage, the first reaction coefficient is calculated to adjust the gas flow rate of the gas pump.

[0127] The target setting and deviation calculation module uses nitrite generated by short-range nitrification reaction as the substrate for anaerobic ammonium oxidation reaction. In the anaerobic ammonium oxidation reaction, the nitrogen concentration of the current reaction time period is fitted according to the obtained nitrite substrate concentration sequence. Based on the nitrogen concentration fitting curve, the actual amount of nitrogen generated in the current time period is obtained. Combined with the expected amount of nitrogen generated in each reaction stage, the nitrogen deviation in each reaction stage is calculated.

[0128] The dynamic deviation detection module is used to set the dynamic deviation threshold of nitrogen concentration in the fitting curve of nitrogen concentration, and to determine whether the deviation value of nitrogen generation in each reaction stage exceeds the dynamic deviation threshold under the current state.

[0129] The PID control and regulation module is used to adjust the load operating parameters using PID control formulas based on the comparison feedback results, and to formulate different adjustment strategies for each reaction stage of anaerobic ammonia oxidation.

[0130] The present invention also provides a short-cut nitrification and anaerobic ammonium oxidation reactor, the reactor comprising a water pump, a stirrer, and an air pump, wherein the water pump, stirrer, and air pump are controlled by the control method of the above-described short-cut nitrification and anaerobic ammonium oxidation reactor.

[0131] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0132] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented in software, the above embodiments can be implemented, in whole or in part, as a computer program product. Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution.

[0133] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0134] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A control method for a short-cut nitrification and anaerobic ammonium oxidation reactor, characterized in that, The specific steps include: Step 1: Monitor the load operating parameters of the coupled reactor and the reaction substrate concentration at the outlet in real time. Determine the reaction stage of the reactor at the current moment based on the reaction time as the current reaction stage. Extract the time series of load operating parameters and reaction substrate concentration from the start time of the current reaction stage to the current moment. The load operating parameters of the reactor include the water pump inlet flow rate, the agitator rotation speed and the gas pump gas flow rate. Step 2: During the short-range nitrification reaction, the nitrite concentration in the current reaction stage is fitted based on the obtained load operation parameter time series and reaction substrate concentration time series. The actual amount of nitrite generated in the current reaction stage is calculated based on the fitted curve. The first reaction coefficient is generated by combining the target amount of nitrite generated in the current reaction stage to adjust the gas flow rate of the gas pump. Step 3: Using the nitrite generated by the short-range nitrification reaction as the substrate for the anaerobic ammonium oxidation reaction, the nitrogen concentration during the current reaction time period is fitted based on the obtained nitrite substrate concentration sequence. The actual amount of nitrogen generated during the current time period is obtained based on the nitrogen concentration fitting curve. The nitrogen deviation in each reaction stage is calculated in combination with the expected amount of nitrogen generated in each reaction stage. Step 4: Set a dynamic deviation threshold for nitrogen concentration in the fitted curve of nitrogen concentration, and determine whether the deviation value of nitrogen generation in each reaction stage exceeds the dynamic deviation threshold under the current state. Step 5: Adjust the load operating parameters using the PID control formula based on the comparison feedback results, and formulate different adjustment strategies for each reaction stage of anaerobic ammonia oxidation.

2. The control method for a short-cut nitrification and anaerobic ammonia oxidation reactor according to claim 1, characterized in that, The method used to establish a time series of reactant concentrations at the reactor outlet by real-time monitoring of the reactant concentration is as follows: Sensors were installed at the reactor outlet to measure nitrite concentration. A timer was set, and the total experimental reaction time was divided into three stages based on a preset total experimental duration: a start-up stage, a rapid reaction stage, and a stable operation stage. Data was recorded in timestamp format to form a time series of substrate concentrations. ,in Indicates the first Each sampling measurement time point, Indicates the first Nitrite concentration at each sampling and measurement time point; The obtained reaction substrate concentration time series is preprocessed, which includes data cleaning and missing value imputation, using the Z-score statistical method to identify and remove outliers in the reaction substrate concentration time series, and using linear interpolation to imput the original outlier positions and missing positions in the reaction substrate concentration time series. After preprocessing, a complete reaction substrate concentration time series is obtained.

3. The control method for a short-cut nitrification and anaerobic ammonia oxidation reactor according to claim 2, characterized in that, The method used to adjust the gas flow rate of the gas pump is as follows: The nitrite concentration at the current reaction stage is fitted to the data, and the first reaction coefficient is calculated. The expected ammonia nitrogen removal rate was obtained, and the nitrite concentration at the current reaction stage was fitted using the time series of load operating parameters and the time series of reaction substrate concentration, respectively, to obtain the nitrite concentration fitting curve under the preset total reaction time. The formula used is as follows: ； in, This represents the fitted curve of nitrite concentration. , They represent in time, The concentration of nitrite at time [time]. It is the end point of the startup phase. It is the end point of the rapid response phase. It is the total duration of the experimental reaction, that is, the end point of the steady-state phase. It is a time variable. , These are the reaction rate constants for the nitrite concentrations during the start-up phase and the rapid reaction phase, respectively. The expected ammonia nitrogen removal rate; The actual amount of nitrite generated in the current reaction stage is obtained by integrating the fitted curve of nitrite concentration using the following formula: ； in, These represent the actual amount of nitrite generated during the current reaction stage. Indicates the start time of the current reaction phase. Indicates the end time of the current reaction phase; The first reaction coefficient is calculated based on the actual amount of nitrite generated at the current reaction stage, combined with the target amount of nitrite generated. The formula used is as follows: ； in, Indicates the first reaction coefficient. This indicates the target amount of nitrite generated during the current reaction stage; The formula for adjusting the pump gas rate, combined with the first reaction coefficient, is used to adjust the gas flow rate of the pump. The formula is as follows: ； in, This indicates the adjusted gas flow rate of the air pump. This indicates the current gas flow rate of the air pump. This is an adjustment coefficient used to control the sensitivity of the adjustment. This is the ideal value for the first reaction coefficient.

4. The control method for a short-cut nitrification and anaerobic ammonia oxidation reactor according to claim 3, characterized in that, The nitrogen concentration during the current reaction period was fitted, and the deviation of nitrogen production in each reaction stage of the anaerobic ammonia oxidation reaction was calculated. The method used was as follows: The nitrogen concentration during the current reaction period was fitted based on the obtained nitrite substrate concentration sequence, using the following formula: ； in, The fitted curve representing nitrogen concentration. , They represent in time, The concentration of nitrogen at time t. , , These are the reaction rate constants of ammonia nitrogen concentration during the start-up phase, rapid reaction phase, and stable operation phase, respectively. The formula used to calculate the actual amount of nitrogen generated in the current time period is: ； in, This indicates the actual amount of nitrogen generated during the current time period; Similarly, the actual nitrogen generation during the start-up phase, rapid response phase, and stable operation phase can be obtained using the above formula. , , The absolute value of the difference between the actual amount of nitrogen produced and the expected amount produced in each stage is the nitrogen deviation. , , .

5. The control method for a short-cut nitrification and anaerobic ammonia oxidation reactor according to claim 4, characterized in that, The method used to set the dynamic deviation threshold of nitrogen concentration in the nitrogen concentration fitting curve is as follows: The anaerobic ammonium oxidation reaction time includes the start-up phase. Rapid response phase and stable operation phase ,in The total experimental reaction run time is denoted as . , For the phased time nodes, the dynamic deviation threshold function is established as follows: ； in, Indicates the time when the reaction terminates. Falling in The threshold for dynamic deviation of nitrogen concentration within a given time period is: , It is an index for a time period, and ; If the dynamic control objective is achieved, then at any time It should meet the following requirements: A piecewise function is used to represent the dynamic deviation threshold of nitrogen concentration: ； in, This indicates the maximum permissible nitrogen concentration deviation threshold during the startup phase. This indicates the nitrogen concentration deviation threshold during the rapid reaction phase. This represents the threshold for nitrogen concentration deviation during the stable phase.

6. The control method for a short-cut nitrification and anaerobic ammonia oxidation reactor according to claim 5, characterized in that, The load operating parameters are adjusted using a PID control formula based on the comparison feedback results. The method used is as follows: If the nitrogen deviation in a certain experimental reaction stage exceeds the corresponding dynamic deviation threshold for nitrogen concentration in that stage, the load operating parameters are adjusted using a PID control formula. The formula is as follows: ； in, This indicates the control scalar values ​​during the current experimental reaction period, including the setpoints for influent flow rate and stirring rate. , , These represent the proportional coefficient, integral coefficient, and differential coefficient, respectively. It is the baseline value of the control scalar for the current experimental reaction time period. This indicates the nitrogen deviation during the current reaction phase. This indicates the time interval from the start of the experiment to the current reaction time. The deviation integral, It represents the derivative of the deviation with respect to time, that is, the instantaneous rate of change of the deviation, which indicates the speed at which the deviation increases or decreases.

7. The control method for a short-cut nitrification and anaerobic ammonium oxidation reactor according to claim 6, characterized in that, Different adjustment strategies were developed for each stage of the experimental reaction, based on the following method: In PID-based dynamic load control, each type of load parameter is regulated by an independent PID controller. It is the water pump inlet flow rate. This refers to the agitator speed. Each load parameter has a safe initial setting reference. The deviation adjustment of the PID output is based on this, plus or minus it. To prevent excessive parameter adjustment from causing system instability, a maximum rate of change and a maximum value range need to be set. The maximum rate of change is: The maximum range of values ​​is: ; During different reaction stages, when the nitrogen deviation exceeds the corresponding dynamic deviation threshold, the following measures are taken: , Two load parameters are adjusted separately to achieve dynamic load control for the anaerobic ammonia oxidation process. The logic method for load control is as follows: During the startup phase, the PID parameters for the water pump inlet flow rate are adjusted, including reducing the proportional gain. To reduce the impact caused by rapid changes in flow, the integral coefficient is gradually increased. To improve the response to long-term deviations, the differential coefficient is increased. To enhance the suppression of flow rate changes and achieve a slow increase in pump flow rate; the PID parameters of the agitator's stirring rate are adjusted, including reducing the proportional gain. To avoid system disturbances caused by rapid changes in rotational speed, the integral coefficient is gradually increased. To improve the response to uneven mixing, the differential coefficient is increased. To slow down the rate of change of rotation speed, the speed of the agitator is increased slowly; During the rapid response phase, the PID parameters for the water pump inlet flow rate are adjusted, including increasing the proportional gain. To enhance the response speed to flow deviations and maintain the integral coefficient To maintain a stable flow rate, the differential coefficient is increased. To avoid flow overshoot and oscillation and achieve rapid response to load fluctuations, the PID parameters of the agitator's stirring rate are adjusted, including increasing the proportional gain. To prevent uneven mixing and maintain the integral coefficient To ensure the stability of stirring, the differential coefficient is increased while keeping it constant. To control the change in stirring rate; During the stable operation phase, the PID parameters of the water pump inlet flow rate are adjusted, including reducing the proportional gain. To maintain the current traffic stability, gradually increase the integral coefficient. To eliminate residual bias and reduce differential coefficients Reduce the sensitivity of adjustments and maintain stable flow; adjust the PID parameters of the agitator's stirring rate, including reducing the proportional gain. To ensure a stable stirring rate, gradually increase the integral coefficient. To maintain a uniform reaction and reduce the differential coefficient This reduces sensitivity to changes in rotation speed and ensures stable stirring.

8. A control system for a short-cut nitrification and anaerobic ammonia oxidation reactor, characterized in that, The control system is used to execute a control method for a short-cut nitrification and anaerobic ammonia oxidation reactor as described in any one of claims 1-7, comprising: The data acquisition module is used to monitor the load operation parameters of the coupled reactor and the reaction substrate concentration at the outlet in real time. Based on the reaction time, it determines the reaction stage of the reactor at the current moment as the current reaction stage, and extracts the time series of load operation parameters and reaction substrate concentration from the start time of the current reaction stage to the current moment. The load operation parameters of the reactor include the water pump inlet flow rate, the agitator rotation speed, and the gas pump gas flow rate. The substrate concentration modeling module is used to fit the nitrite concentration of the current reaction stage in the short-range nitrification process based on the obtained load operation parameter time series and reaction substrate concentration time series. Based on the fitted curve, the actual amount of nitrite generated in the current reaction stage is calculated. Combined with the target amount of nitrite generated in the current reaction stage, the first reaction coefficient is calculated to adjust the gas flow rate of the gas pump. The target setting and deviation calculation module uses nitrite generated by short-range nitrification reaction as the substrate for anaerobic ammonium oxidation reaction. In the anaerobic ammonium oxidation reaction, the nitrogen concentration of the current reaction time period is fitted according to the obtained nitrite substrate concentration sequence. Based on the nitrogen concentration fitting curve, the actual amount of nitrogen generated in the current time period is obtained. Combined with the expected amount of nitrogen generated in each reaction stage, the nitrogen deviation in each reaction stage is calculated. The dynamic deviation detection module is used to set the dynamic deviation threshold of nitrogen concentration in the fitting curve of nitrogen concentration, and to determine whether the deviation value of nitrogen generation in each reaction stage exceeds the dynamic deviation threshold under the current state. The PID control and regulation module is used to adjust the load operating parameters using PID control formulas based on the comparison feedback results, and to formulate different adjustment strategies for each reaction stage of anaerobic ammonia oxidation.

9. A short-cut nitrification and anaerobic ammonium oxidation reactor, the reactor comprising a water pump, a stirrer, and an air pump, characterized in that, The water pump, agitator, and air pump are controlled using the control method for a short-cut nitrification and anaerobic ammonia oxidation reactor as described in any one of claims 1-7.

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