A device and method for treating aquaculture wastewater

Abstract

This invention relates to the field of wastewater purification technology, specifically to a device and method for treating aquaculture wastewater. The device includes: a wastewater parameter extraction module, a flow direction control and determination module, a pollutant data decoupling module, a nitrogen resonance identification module, and a risk warning output module. In this invention, by dynamically adjusting the oxidation-reduction potential and instantaneous influent flow rate, the real-time rate of change of the wastewater's oxidation-reduction state and the relative increase in influent flow rate are extracted. This efficiently captures minute fluctuations in the wastewater's water quality state, promptly identifying whether the water body is in the critical transition zone between oxidation and reduction states, avoiding lag or misjudgment in water quality control responses. Furthermore, by utilizing pollutant concentration perturbation stripping technology, the interference of flow fluctuations on pollutant concentration changes is effectively isolated, ensuring the purity and reliability of pollutant change trends and significantly improving the accuracy of identifying the synergistic change trends of nitrogen pollutants.

Description

Technical Field

[0001] This invention relates to the field of wastewater purification technology, and in particular to a device and method for treating wastewater from aquaculture. Background Technology

[0002] The field of wastewater purification technology encompasses the collection and treatment of wastewater discharged during aquaculture, aiming to reduce water pollution and improve the efficiency of water resource recycling. The core aspects of this technology include the removal of pollutants such as suspended solids, organic pollutants, nitrogen and phosphorus nutrients, and pathogenic microorganisms from the water.

[0003] Among them, the treatment system for aquaculture wastewater refers to a multi-stage combined water treatment device constructed during the aquaculture production process to target pollutants such as ammonia nitrogen, nitrite, total phosphorus and suspended solids in the wastewater. This is achieved by setting up a primary sedimentation structure to remove large particulate impurities, setting up a microbial reaction unit for the biological transformation of nitrogen and phosphorus pollutants, and configuring an artificial wetland structure to further absorb residual nutrients.

[0004] Current technologies for treating aquaculture wastewater primarily rely on fixed physical sedimentation and biological reaction units, lacking real-time sensing and response mechanisms to dynamic changes in wastewater quality. This makes it difficult to detect sudden changes or anomalies in water quality during treatment. Changes in redox states cannot be effectively identified, and fluctuations in influent flow rate are not adequately considered. Consequently, in transitional zones where water quality changes rapidly, wastewater path allocation lacks scientific basis, easily leading to control delays or treatment failures. For example, in cases of sudden surges in influent flow rate, the sedimentation structure may react too slowly, resulting in excessive emissions of suspended solids. Regarding pollutant monitoring, the synergistic changes in ammonia nitrogen and nitrate nitrogen are not systematically analyzed, often leading to distorted concentration measurements due to flow disturbances, affecting the assessment and control of pollutant removal efficiency. Due to the lack of in-depth identification of the synergistic fluctuation characteristics of nitrogen pollutants, existing systems cannot accurately predict potential pollution linkage risks when treating wastewater with high nitrogen loads, increasing the probability of water quality anomalies and environmental pollution, and limiting the efficiency of aquaculture wastewater treatment. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and to propose a device and method for treating aquaculture wastewater.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a treatment device for aquaculture wastewater, the device comprising the following modules:

[0007] The tailwater parameter extraction module uses an instantaneous flow sensor to detect the oxidation-reduction potential in the tailwater and the instantaneous influent flow rate. Based on the rate of change of the oxidation-reduction potential in the tailwater over a specified time and the relative growth rate of the instantaneous influent flow rate, a set of tailwater flow direction control response parameters is constructed.

[0008] The flow direction control determination module performs path allocation control based on the normalized ratio of the change rate of oxidation-reduction potential in the tailwater to the relative growth rate of the instantaneous influent flow rate in the tailwater flow direction control response parameter set, and outputs the tailwater path allocation control result.

[0009] The pollutant data decoupling module obtains continuous data on the synchronous concentrations of ammonia nitrogen and nitrate nitrogen in the effluent, as well as the fluctuation amplitude data of the entire influent flow rate, based on the tailwater path allocation control results, and performs perturbation decoupling to construct a basic pollutant response sequence.

[0010] The nitrogen resonance identification module identifies the change trend sequences of ammonia nitrogen and nitrate nitrogen in the basic response sequence of the pollutants, extracts the point set of overlapping intervals of the change trends of ammonia nitrogen and nitrate nitrogen in the sequence, and obtains the nitrogen resonance response identification result.

[0011] The risk warning output module identifies pollutant-related fluctuation behavior and outputs abnormal fluctuation warning commands based on the nitrogen resonance response identification results, thereby obtaining the tailwater treatment risk warning results.

[0012] As a further aspect of the present invention, the tailwater flow direction control response parameter set includes the gradient of redox potential change per unit time, the amplitude of instantaneous influent flow rate change, and abrupt change points in the ratio sequence; the tailwater path allocation control result includes path switching trigger signal, influent direction selection identifier, and control command timestamp; the pollutant response basic sequence includes ammonia nitrogen change curve nodes, nitrate nitrogen concentration gradient trajectory, and concentration value sequence after disturbance stripping; the nitrogen resonance response identification result includes consistency judgment of change trend direction, trend superposition window, and time axis intersection set; and the tailwater treatment risk warning result specifically includes pollutant linkage risk identifier, water quality abnormality status label, and warning response level.

[0013] As a further aspect of the present invention, the tailwater parameter extraction module includes:

[0014] The redox change extraction submodule acquires the time series data of oxidation-reduction potential (ORP) of tailwater collected by the water quality testing equipment, extracts the rate of increase and rate of decrease of data points in the sequence within a set monitoring period, and generates a redox change rate sequence.

[0015] The flow rate change calculation submodule obtains the instantaneous influent flow data within the time period corresponding to the redox change rate sequence, calculates the relative growth rate of influent flow at continuous time points, and generates an instantaneous flow rate growth rate sequence.

[0016] The parameter set construction submodule filters synchronously changing time period data based on the time correspondence between the redox change rate sequence and the instantaneous flow rate growth rate sequence to obtain the tailwater flow direction regulation response parameter set.

[0017] As a further aspect of the present invention, the flow direction control determination module includes:

[0018] The normalized ratio generation submodule obtains two sets of parameters at the same time node based on the oxidation-reduction potential change rate and the relative growth rate of instantaneous influent flow rate in the tailwater flow direction control response parameter set. After normalizing the two parameters to the 0 to 1 range using the range normalization method, the ratio is calculated to generate a normalized ratio sequence.

[0019] The transition segment identification submodule selects data from the continuous time period in the normalized ratio sequence, and determines whether the selected segment ratio is in the characteristic interval of the redox boundary by comparing the fluctuation direction of the selected segment ratio with the redox partition threshold change characteristics, thereby obtaining the transition state determination interval.

[0020] The path control instruction output submodule calls the time point within the transition state determination interval to check whether the time point meets the path switching logic condition. If it does, it is marked as a trigger event segment and the tailrace path allocation control result is generated.

[0021] As a further aspect of the present invention, the pollutant data decoupling module includes:

[0022] Based on the tailwater path allocation control results, the concentration data acquisition submodule acquires the continuous concentrations of ammonia nitrogen and nitrate nitrogen in the tailwater obtained by the water quality testing equipment, extracts the numerical changes of each indicator within a fixed period, and establishes ammonia nitrogen concentration sequence and nitrate nitrogen concentration sequence in chronological order to generate a pollutant concentration sequence set.

[0023] The disturbance impact identification submodule extracts the continuous change data of the influent flow rate within the same time period based on the pollutant concentration sequence set, calculates the amplitude and fluctuation range within each cycle, judges the degree of interference of the flow fluctuation within each time period, and obtains the level of flow disturbance impact.

[0024] The disturbance signal stripping submodule splits the pollutant concentration sequence set into fluctuation components according to the influence level of the flow disturbance, distinguishes frequency components using ensemble empirical mode decomposition, and extracts the stripped ammonia nitrogen change trend and nitrate nitrogen change trend to obtain the basic pollutant response sequence.

[0025] As a further aspect of the present invention, the nitrogen-based resonance identification module includes:

[0026] The trend feature extraction submodule extracts the ammonia nitrogen response sequence and nitrate nitrogen response sequence from the pollutant response base sequence, respectively, extracts the change data of ammonia nitrogen concentration in a continuous time period, calculates the corresponding second-order steering value, identifies the slope change trend of nitrate nitrogen concentration under the same period, and generates trend change feature groups.

[0027] The change point pairing and identification submodule uses the longest common subsequence algorithm to sequentially compare the trend change direction marker sequences of ammonia nitrogen and nitrate nitrogen based on the trend change feature group, and obtains the time-series key pairing point group;

[0028] The resonance interval construction submodule calls the time-series key pairing point group, sequentially determines the time span and overlap density between consecutive pairing points, filters the overlap windows that satisfy the direction consistency and sequence continuity, and establishes the nitrogen-type resonance response identification results.

[0029] As a further aspect of the present invention, the risk warning output module includes:

[0030] The synchronous window extraction submodule extracts the timestamp data of ammonia nitrogen trend change points and nitrate nitrogen change points based on the nitrogen resonance response identification results, compares the time positions of the two types of change points, filters point groups within the overlapping time range, and generates a synchronous change window set.

[0031] The trend judgment submodule calls the response direction of each point group in the synchronous change window set, compares the change direction of ammonia nitrogen with the change direction of nitrate nitrogen one by one, judges whether the directions are consistent, calculates the proportion of consistent directions among all effective change pairs, and obtains the trend consistency rate.

[0032] The instruction information generation submodule determines whether the response threshold is exceeded based on the consistency rate of the change trend. If it is, it is marked as a warning state segment, the corresponding time and type are recorded, a pollutant fluctuation warning instruction is generated, and the tailwater treatment risk warning result is obtained.

[0033] A method for treating aquaculture wastewater, wherein the method is performed based on the aforementioned aquaculture wastewater treatment device, and includes the following steps:

[0034] S1: By detecting the oxidation-reduction potential and instantaneous influent flow rate in the effluent, and based on the rate of change of the oxidation-reduction potential in the effluent over a specified time and the relative growth rate of the instantaneous influent flow rate, a set of effluent flow direction control response parameters is constructed.

[0035] S2: Based on the normalized ratio of the rate of change of oxidation-reduction potential in the tailwater to the relative growth rate of the instantaneous influent flow rate in the tailwater flow direction control response parameter set, determine whether the current influent is in the transition zone between oxidation-reduction states, and output the tailwater path allocation control result based on the judgment result.

[0036] S3: Perform perturbation decoupling on the continuous data of synchronous concentrations of ammonia nitrogen and nitrate nitrogen in the effluent, as well as the data of fluctuation amplitude of the entire influent flow rate, to construct a basic sequence of pollutant response;

[0037] S4: By identifying the change trend sequences of ammonia nitrogen and nitrate nitrogen in the basic response sequence of the pollutants, the point set of overlapping intervals of the change trends of ammonia nitrogen and nitrate nitrogen in the sequence is extracted to obtain the nitrogen resonance response identification result;

[0038] S5: Based on the nitrogen resonance response identification results, identify the pollutant-related fluctuation behavior and output abnormal fluctuation warning instructions to obtain the tailwater treatment risk warning results.

[0039] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0040] This invention extracts the real-time rate of change of the redox state in the effluent and the relative increase in the influent flow rate based on the dynamic changes of redox potential and instantaneous influent flow rate. This efficiently captures minute fluctuations in the effluent water quality and promptly identifies whether the water body is in the critical transition zone between redox states, avoiding lag or misjudgment in water quality control responses. Furthermore, by utilizing pollutant concentration perturbation stripping technology, the interference of flow fluctuations on pollutant concentration changes is effectively isolated, ensuring the purity and reliability of pollutant change trends and significantly improving the accuracy of identifying the synergistic change trends of nitrogen pollutants. Further, by extracting the trend sequences of ammonia nitrogen and nitrate nitrogen concentration changes, the overlapping characteristics of their change ranges are identified, establishing a nitrogen resonance response zone. This accurately identifies risk signals of synergistic fluctuations of nitrogen pollutants in the water body, enhancing the predictive ability for abnormal pollutant fluctuation behavior. Moreover, based on trend consistency analysis, the risk level and type of water quality anomalies can be dynamically output, providing more forward-looking risk warning support for effluent treatment. This avoids the passive response and treatment lag present in traditional treatment methods, effectively improving the intelligence and safety level of aquaculture effluent treatment. Attached Figure Description

[0041] Figure 1 This is a flowchart of the apparatus of the present invention;

[0042] Figure 2 This is a flowchart of the tailwater parameter extraction module of the present invention;

[0043] Figure 3 This is a flowchart of the flow direction control and determination module of the present invention;

[0044] Figure 4 This is a flowchart of the pollutant data decoupling module of the present invention;

[0045] Figure 5 This is a flowchart of the nitrogen-based resonance recognition module of the present invention;

[0046] Figure 6 This is a flowchart of the risk warning output module of the present invention. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0048] In the description of this invention, it should be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, in the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0049] Please see Figure 1 The present invention provides a technical solution: a device for treating aquaculture wastewater, the device comprising the following modules:

[0050] The tailwater parameter extraction module uses an instantaneous flow sensor to detect the oxidation-reduction potential in the tailwater and the instantaneous influent flow rate. Based on the rate of change of the oxidation-reduction potential in the tailwater over a specified time and the relative growth rate of the instantaneous influent flow rate, a set of tailwater flow direction control response parameters is constructed.

[0051] The flow direction control determination module performs path allocation control based on the normalized ratio of the change rate of oxidation-reduction potential in the tailwater to the relative growth rate of the instantaneous influent flow rate in the tailwater flow direction control response parameter set, and outputs the tailwater path allocation control results.

[0052] The pollutant data decoupling module obtains continuous data on the synchronous concentrations of ammonia nitrogen and nitrate nitrogen in the effluent, as well as the fluctuation amplitude data of the entire influent flow rate, based on the effluent path allocation control results, and performs perturbation decoupling to construct a basic sequence of pollutant response.

[0053] The nitrogen resonance identification module identifies the changing trend sequences of ammonia nitrogen and nitrate nitrogen in the basic pollutant response sequence, extracts the point set of overlapping intervals of the changing trends of ammonia nitrogen and nitrate nitrogen in the sequence, and obtains the nitrogen resonance response identification result.

[0054] The risk warning output module identifies pollutant-related fluctuation behavior and outputs abnormal fluctuation warning commands based on the nitrogen resonance response identification results, thus obtaining the effluent treatment risk warning results.

[0055] The tailwater flow direction control response parameter set includes the gradient of redox potential changes per unit time, the magnitude of instantaneous influent flow rate changes, and abrupt change points in the ratio sequence. The tailwater path allocation control results include path switching trigger signals, influent direction selection identifiers, and control command timestamps. The pollutant response basic sequence includes ammonia nitrogen change curve nodes, nitrate nitrogen concentration gradient trajectory, and concentration value sequence after disturbance stripping. The nitrogen resonance response identification results include consistency judgment of change trend direction, trend superposition window, and time axis intersection set. The tailwater treatment risk warning results specifically include pollutant linkage risk identifiers, water quality abnormality status labels, and warning response levels.

[0056] Please see Figure 2 The tailwater parameter extraction module includes:

[0057] The redox change extraction submodule acquires the time series data of oxidation-reduction potential (ORP) of tailwater collected by the water quality testing equipment, extracts the rate of increase and rate of decrease of data points in the sequence within a set monitoring period, and generates a redox change rate sequence.

[0058] Time-series data of oxidation-reduction potential (ORP) in effluent were acquired using water quality testing equipment. Sampling intervals were every 10 minutes, and the monitoring period was set to 120 minutes; therefore, a total of 12 sets of data were collected, denoted as follows: , of which letters This represents the redox potential value, with the unit being millivolts (mV). Represents the first in a time series One sampling point, Indicates the first Data points at the next time step, for example , The ORP values ​​for the first and second sampling points are 215mV and 220mV, respectively. The rate of change per unit time is calculated using a difference method for all adjacent points, and the formula is: ,in Indicates the first and The rate of change of ORP between sampling points, in millivolts per minute (mV / min), where t is the time interval, taken as 10 minutes. Substituting the example data yields... Millivolts per minute (mV / min) indicates that the ORP increases by an average of 0.5 mV per minute during that time period. (All) The value is assigned to the increasing sequence. The value is categorized as a decreasing sequence. The system sets the judgment threshold to be an absolute value of the rate of change greater than or equal to 0.2 mV / min. This value is based on the maximum fluctuation under normal stable operating conditions during system operation, and the fluctuation range is taken from the 95% confidence interval of the sample standard deviation. If the rate of change exceeds the threshold for three consecutive time periods, it is considered an abnormal change process. For example, if the three consecutive values ​​are... , , If all conditions are met, the time periods corresponding to sampling points 1 to 4 are extracted to generate a redox rate sequence. This sequence is used for subsequent time consistency comparison with changes in influent flow rate to identify the linkage between sudden changes in water quality and fluctuations in water volume.

[0059] The flow rate change calculation submodule obtains the instantaneous influent flow data within the time period corresponding to the redox change rate sequence, calculates the relative growth rate of influent flow at continuous time points, and generates an instantaneous flow rate growth rate sequence.

[0060] Based on the determined effective time period of change to Collect the corresponding instantaneous inflow rate data. , of which letters This indicates the inflow rate, expressed in cubic meters per hour (m³ / h). Indicates the first Each sampling time point This represents the sampled value at the next moment. The sampling frequency is consistent with ORP, which is once every 10 minutes. Let the sampled data be... , , , The calculation is performed using the relative growth rate, and the formula is as follows: ,in Indicates the first The growth rate of influent flow rate over a given period is a dimensionless proportion. , For example, the calculation is as follows This means the influent flow rate increased by approximately 2.63% during that period. After performing the same calculation on all data, only data with an absolute relative growth rate greater than or equal to 0.01 (i.e., 1%) were retained. This was based on the flow rate fluctuation standard under normal system load conditions. Fluctuations below 1% are often caused by sensor noise, and invalid data segments were discarded. , , All three segments show positive growth and exceed the threshold; therefore, the corresponding segments are retained. to The time range is used to form an instantaneous flow rate growth rate sequence. This sequence is used to determine whether inflow disturbances are associated with abnormal ORP changes.

[0061] The parameter set construction submodule filters synchronously changing time period data based on the time correspondence between the redox change rate sequence and the instantaneous flow rate growth rate sequence to obtain the tailwater flow direction regulation response parameter set;

[0062] The redox change rate sequence and the instantaneous flow rate growth rate sequence were time-stamped and aligned according to the sampling point index. Match the data segments and analyze whether ORP and traffic change synchronously within the same time window. Let the joint decision condition be: millivolts per minute and This joint threshold is determined based on historical linkage data statistics, using the 90th percentile of both the ORP change rate and the traffic growth rate as the screening criteria. For example... to In the section, if , , millivolts per minute , , If the flow rate growth rate of group 3 does not reach the set value, only the data from segments 1 and 2 meet the joint condition. The screening results are used to determine the core time period for tailwater regulation response, and the time period is divided into... , Mark the effective linkage segment, summarize the results and establish a time index table, and finally construct the tailwater flow direction control response parameter set.

[0063] Please see Figure 3 The flow direction control and determination module includes:

[0064] The normalized ratio generation submodule obtains two sets of parameters at the same time point based on the rate of change of oxidation-reduction potential and the relative growth rate of instantaneous influent flow rate in the tailwater flow direction control response parameter set. After normalizing the two parameters to the 0 to 1 range using the range normalization method, the ratio is calculated to generate a normalized ratio sequence.

[0065] Based on the data of redox potential change rate and instantaneous influent flow rate relative growth rate extracted from the tailrace flow direction control response parameter set, the parameter index range is first set to... ,in Indicates the first Each synchronous monitoring time point Indicates the first The redox potential change rate at each time point is expressed in millivolts per minute (mV / min). This represents the relative growth rate of the instantaneous inflow rate at a given time point, and is a unitless percentage value. [Get all] and Then, the maximum and minimum values ​​of the two sets of data are calculated respectively, and the range normalization method is used to standardize them to the interval. The normalization formula is:

[0066] ;

[0067] in Indicates the first The original parameter values ​​at each time point This represents the minimum value in the set of parameters. This represents the maximum value among the parameters in this set. This represents the normalized result. Taking the redox rate of change sequence as an example, if its value is {0.2, 0.5, 0.8, 0.4} millivolts per minute, then the maximum value is... minimum value Calculated , After normalizing all time points, sort by time index. For normalization results and Establish a one-to-one correspondence and calculate the ratio for each group:

[0068] ;

[0069] in Indicates the first The ratio of the two parameters after normalization at each time point. For example, when , ,but The ratios calculated at all time points are organized into a sequence in this way, and finally the normalized ratio sequence is obtained.

[0070] The transition zone identification submodule selects data from the continuous time period in the normalized ratio sequence. By comparing the fluctuation direction of the selected segment ratio with the redox partition threshold change characteristics, it determines whether the selected segment ratio is in the characteristic interval of the redox state boundary, and obtains the transition state determination interval.

[0071] In the normalized ratio sequence, select a continuous time period. Let the ratio of this segment be denoted as . Each of them Indicates the first The ratio of normalized parameters at each time point is used. The trend of this ratio is extracted to identify whether there is a consistent fluctuation sequence. If it shows monotonically increasing, monotonically decreasing, or alternating high-frequency oscillations, it is classified as a structural fluctuation segment. The system references the redox state zoning characteristics: the common ORP value in the aerobic zone is 300 to 500 mV, and the common ORP value in the denitrification zone is 0 to 200 mV. Considering that the ratio is the ratio of ORP to the normalized flow rate, the system defines time points with ratios between 1.5 and 2.5 as the redox boundary indicator segment. Each item in the ratio sequence is compared to see if there are three consecutive items falling within this interval, for example... , , If it is, it is identified as a boundary segment, and the corresponding time period is... to The event interval is categorized into all time periods that meet the conditions, and a transitional state determination interval is constructed.

[0072] The path control instruction output submodule calls the time point within the transition state determination interval to check whether the time point meets the path switching logic condition. If it does, it is marked as a trigger event segment and the tailrace path allocation control result is generated.

[0073] Call all time point indices within the identified transition state determination interval For each time point, the path switching logic is executed, and the judgment conditions are divided into two items: First, the normalization ratio of the current time point and the two points after it is determined. , , First, determine if all values ​​fall within the range of 1.5 to 2.5. If so, a stable boundary phenomenon is considered to exist. Second, determine if the time interval between the current triggering event and the previous triggering event exceeds 30 minutes. If the time isolation condition is met, then the current time interval is considered stable. The point is identified as a valid trigger point and forms a three-point trigger segment with the following two points. The segment data that meets the conditions is written as a path switching event to the path scheduling cache, recording the corresponding time point, ratio, path branch number, and an output structure is constructed for scheduling interface calls.

[0074] Please see Figure 4 The pollutant data decoupling module includes:

[0075] The concentration data acquisition submodule, based on the tailwater path allocation control results, collects the continuous concentrations of ammonia nitrogen and nitrate nitrogen in the tailwater obtained by the water quality testing equipment, extracts the numerical changes of each indicator within a fixed period, and establishes ammonia nitrogen concentration sequence and nitrate nitrogen concentration sequence in chronological order to generate a pollutant concentration sequence set.

[0076] The concentrations of ammonia nitrogen and nitrate nitrogen in the effluent were collected from the water quality testing equipment. The sampling period was set at once every 10 minutes, with a total sampling time of 2 hours, resulting in 12 sets of data. The data index is [data index missing]. ,in Indicates the first Ammonia nitrogen concentration values ​​at each time point (unit: milligrams per liter, mg / L). This represents the nitrate nitrogen concentration at the corresponding time point. For example, the sampled data is as follows:

[0077] ;

[0078] ;

[0079] The concentration values ​​of two indicators were extracted for each period, and two independent sequences were constructed in chronological order, named the ammonia nitrogen concentration sequence and the nitrate nitrogen concentration sequence, respectively, to form a bivariate dataset. This dataset serves as the basic input for the temporal changes of pollutants in subsequent analyses, ultimately yielding a set of pollutant concentration sequences.

[0080] The disturbance impact identification submodule is based on the pollutant concentration sequence set. It extracts the continuous change data of the influent flow rate within the same time period, calculates the amplitude and fluctuation range within each cycle, judges the degree of interference of the flow fluctuation within each time period, and obtains the level of flow disturbance impact.

[0081] Based on the pollutant concentration sequence set, the influent flow rate value corresponding to each time point is extracted. The unit is cubic meters per hour (m³ / h), and the flow rate data is set as follows:

[0082] ;

[0083] First, calculate the fluctuation amplitude for each monitoring period, and then use the difference method to process adjacent points. For example, the fluctuation amplitude of the first period is... The largest fluctuation occurred The average fluctuation range is For cubic meters per hour, an interference threshold of 0.6 is set, derived from the average normal fluctuation during the system's historical operation plus a standard deviation (i.e., average approximately 0.4, plus standard deviation approximately 0.2). If the fluctuation amplitude in a certain period is ≥0.6, that period is marked as an interference interval. The fluctuation intensity within each period is recorded sequentially to form a disturbance intensity label sequence, where, for example, periods 3, 4, and 12 are marked as high interference, and others as low interference. The final output is the flow disturbance impact level, used for pollutant stripping treatment.

[0084] The disturbance signal stripping submodule splits the pollutant concentration sequence set into fluctuation components according to the level of flow disturbance, distinguishes frequency components using ensemble empirical mode decomposition, and extracts the stripped ammonia nitrogen change trend and nitrate nitrogen change trend to obtain the basic pollutant response sequence.

[0085] Based on the level of impact of flow disturbance, the pollutant concentration sequence set Interference removal was performed. The removal strategy was as follows: for periods with high interference (such as periods 3, 4, and 12), the trend was reconstructed to remove short-term rapid oscillations, retaining only the trend-based, gradual changes; for periods with low interference, the original main trend of the data was retained, and the curve was smoothed using an average sliding window method. For example, the ammonia nitrogen concentrations in periods 5, 6, and 7 were 4.0, 3.8, and 3.7, respectively, and a window width of 3 was used, with the reconstructed values ​​being... The data were measured in milligrams per liter. After reconstruction, the ammonia nitrogen and nitrate nitrogen data sets were processed independently, and the results were sequences after removing perturbations, representing the main trend changes in pollutant concentrations. The final processed results were named the ammonia nitrogen trend sequence and the nitrate nitrogen trend sequence, respectively, and merged into a single linked structure, namely the pollutant response basic sequence, for subsequent identification of nitrogen resonance change characteristics.

[0086] Please see Figure 5 The nitrogen-based resonance identification module includes:

[0087] The trend feature extraction submodule extracts ammonia nitrogen response sequence and nitrate nitrogen response sequence from the pollutant response base sequence, extracts ammonia nitrogen concentration change data over a continuous time period, calculates the corresponding second-order steering value, identifies the slope change trend of nitrate nitrogen concentration under the same period, and generates trend change feature group.

[0088] Ammonia nitrogen response sequence based on pollutant response basic sequences Response sequence with nitrate nitrogen , of which letters Indicates concentration. Indicates ammonia nitrogen. Indicates nitrate nitrogen, Indicates the first Sampled values ​​at each time point, with time point numbers starting from... arrive For example, take The specific concentration data is as follows mg per liter and mg / L, firstly extract the first difference of the change in ammonia nitrogen concentration. ,in, Indicates the current time point The next consecutive sampling point, for example: mg per liter, mg per liter, mg per liter, The concentration is calculated in milligrams per liter, and then the second-order guided value of ammonia nitrogen concentration is calculated from the difference between every two consecutive first-order differences. ,in This represents an operation on adjacent first-order differences, for example: mg per liter, mg per liter, mg / L, and simultaneously for the nitrate nitrogen response sequence, the slope change of two consecutive points is extracted sequentially, defined as ,in Minutes are a fixed sampling time interval, for example: mg per liter per minute mg per liter per minute mg per liter per minute Milligrams per liter per minute, ultimately leading to a second-order guided value sequence of ammonia nitrogen. Trend sequence of nitrate nitrogen slope The data are merged to form a trend change feature group, which serves as the basis for subsequent trend direction labeling and matching comparison.

[0089] The change point pairing and identification submodule uses the longest common subsequence algorithm to sequentially compare the trend change direction marker sequences of ammonia nitrogen and nitrate nitrogen based on the trend change feature group, and obtains the time-series key pairing point group;

[0090] Based on the trend change feature set, the direction marker sequence of the second-order steering value change of ammonia nitrogen was first extracted. , of which letters Indicates direction marker, Indicates ammonia nitrogen. For the first Each monitoring time point is marked according to the sign of the second-order guidance value of ammonia nitrogen, and it is stipulated that if... but ,like but ,like but ,For example: , , Forming ammonia nitrogen orientation marker sequences Similarly, the nitrate slope change direction marker sequence was processed. ,in Represents nitrate nitrogen, if but ,like but ,For example: , , , This forms a nitrate nitrogen orientation marker sequence:

[0091] ;

[0092] Then, the two direction marker sequences are matched bitwise using the direct numerical calculation formula for the longest common subsequence: ;

[0093] in The time index of the comparison, the matching function If the two directions are the same, otherwise the value is 0. For example: The matching process is as follows: , , Therefore, the cumulative LCS match sum in this example is 0. If the ammonia nitrogen direction marker is adjusted to... The matching functions are as follows: , , The cumulative sum of LCS is 3. The final LCS value is used to determine the synchronicity of the trend changes of ammonia nitrogen and nitrate nitrogen. This matching result directly determines the extraction of subsequent key pairing point groups in the time series.

[0094] The resonance interval construction submodule calls the time-series key pairing point group, sequentially determines the time span and overlap density between consecutive pairing points, filters the overlap windows that satisfy the direction consistency and sequence continuity, and establishes the nitrogen-type resonance response identification results;

[0095] Call the timing critical pairing point group, set the pairing point group. ,in The first one representing the ammonia nitrogen direction matching A pairing point index, This represents the index of the corresponding nitrate nitrogen orientation matching point, and the time span between consecutive pairing points is determined sequentially. For example, the pairing point group is The time span of the first pairing point is The second group is a time interval. There are two time intervals, each corresponding to 10 minutes. Therefore, the first group has a time span of 10 minutes, the second group has a time span of 20 minutes, and the time span threshold is set to 20 minutes. If the span... If the temporal continuity is satisfied, the overlap density of the paired point groups can be further determined. The number of matching points is 3, and the total number of samples is 5. An overlap density threshold of 0.3 was set. If the density was greater than the threshold, the overlap window was retained; otherwise, it was filtered out. Finally, for all paired segments that met the time span and overlap density threshold, the direction of ammonia nitrogen and nitrate nitrogen was further verified to see if they were consistent. If there were two or more consecutive paired points with the same direction, the paired segment was marked as a valid overlap window. All valid overlap windows were integrated to establish a complete nitrogen resonance response identification result.

[0096] Please see Figure 6 The risk warning output module includes:

[0097] The synchronous window extraction submodule extracts the timestamp data of ammonia nitrogen trend change points and nitrate nitrogen change points based on the nitrogen resonance response identification results, compares the time positions of the two types of change points, filters point groups within the overlapping time range, and generates a set of synchronous change windows.

[0098] Based on the nitrogen resonance response identification results, the timestamp data of ammonia nitrogen trend change points and nitrate nitrogen change points are first extracted. The set of timestamps for ammonia nitrogen change points is denoted as […]. ,in Indicates the first The sampling time of each ammonia nitrogen change point, and the set of timestamps for each nitrate nitrogen change point are denoted as […]. ,in Indicates the first The sampling time for each nitrate nitrogen change point is used to iterate through all ammonia nitrogen change points, for each... Compare the differences with the time of nitrate nitrogen change point one by one, and calculate ,like If both are within the synchronous change window, then it is determined that they are within the window of synchronous change. The set synchronization time tolerance threshold is set to 10 minutes, determined based on the typical hysteresis cycle of biological reactions to nitrogen pollutants. For example, if... minute, Minutes, matching results are If a set of points that changes synchronously exists is determined, all such sets are extracted and denoted as a set. This ultimately generates a set of synchronously changing windows.

[0099] The trend judgment submodule calls the response direction of each point group in the synchronous change window set, compares the change direction of ammonia nitrogen with the change direction of nitrate nitrogen one by one, determines whether the directions are consistent, calculates the proportion of consistent directions among all effective change pairs, and obtains the trend consistency rate.

[0100] Call the synchronous change window collection For each data point group, extract the ammonia nitrogen change direction markers for each data point group sequentially. Marking the direction of nitrate nitrogen change , of which letters Indicates the direction of change. Indicates ammonia nitrogen. Indicates nitrate nitrogen, and They represent the first The ammonia nitrogen change point and the first The value of each nitrate nitrogen change point follows the rule: if the change trend is positive... If negative If there is no change For each group of synchronous change points Determine if the ammonia nitrogen direction is consistent with the nitrate nitrogen direction, and then perform the following operation: If If the directions are consistent, then the point group is considered a consistent point; otherwise, it is considered an inconsistent point. This process is repeated for all synchronized change point groups. Let the total number of synchronized point groups be 1. The number of points with the same direction is Define the matching function If the directions are the same, otherwise Based on this, the consistency rate of change trends The complete calculation formula is:

[0101] ;

[0102] The summation symbol Represents the set of windows that change synchronously. Matching function for all point groups The results are summed, with the numerator representing the number of all groups of points with consistent directions and the denominator representing the total number of groups of points with synchronous changes. An example calculation is shown below: Assume a set of synchronous change windows. It contains 5 point groups, whose corresponding directions for ammonia nitrogen and nitrate nitrogen are respectively... By comparing them one by one, the first group is consistent, the second group is inconsistent, the third group is consistent, the fourth group is considered inconsistent because the ammonia nitrogen direction is 0, and the fifth group is consistent. Therefore, the number of groups with consistent points is... Total number of points Substitute into the formula to calculate: The consistency rate of the change trend is 60%. This consistency rate is the key basis for whether to generate a pollutant fluctuation warning instruction. It is directly compared with the response threshold to determine whether to trigger the warning state.

[0103] The instruction information generation submodule determines whether the response threshold is exceeded based on the consistency rate of the change trend. If it is, it marks the warning state segment, records the corresponding time and type, generates a pollutant fluctuation warning instruction, and obtains the tailwater treatment risk warning result.

[0104] Consistency rate based on changing trends Determine whether the set response threshold has been exceeded. ,in The threshold for the consistency rate of change trends is set at 0.7, based on the median value from historical data statistics of the system. When a warning state segment is defined, the time range of this segment is recorded as the interval between the earliest and latest times of all point groups within the synchronous change window, denoted as... For example, in this case If the time points are 10, 20, 30, 40, and 50 minutes respectively, then the warning zone is... The warning type is defined as "nitrogen resonance anomaly" and a pollutant fluctuation warning instruction is generated. The instruction includes four parts: trigger time period. The warning type, the triggering reason "consistency rate of change trend exceeds the threshold", and the consistency rate of change trend. For example, the generated instruction is: trigger time period "10-50 minutes", warning type "nitrogen resonance anomaly", trigger reason "consistency rate of change trend exceeds threshold", and consistency rate of change trend "60%". Finally, the warning instruction is pushed to the pollutant monitoring and warning system in the form of structured data to complete the pollutant risk monitoring task.

[0105] A method for treating aquaculture wastewater, the method being performed based on the aforementioned aquaculture wastewater treatment device, includes the following steps:

[0106] S1: By detecting the oxidation-reduction potential and instantaneous influent flow rate in the effluent, and based on the rate of change of the oxidation-reduction potential in the effluent over a specified time and the relative growth rate of the instantaneous influent flow rate, a set of effluent flow direction control response parameters is constructed.

[0107] S2: Based on the normalized ratio of the rate of change of redox potential in the tailwater to the relative growth rate of the instantaneous influent flow rate in the tailwater flow direction control response parameter set, determine whether the current influent is in the transition zone between redox states, and output the tailwater path allocation control result based on the judgment result.

[0108] S3: Perform perturbation decoupling on the continuous data of synchronous concentrations of ammonia nitrogen and nitrate nitrogen in the effluent, as well as the data of fluctuation amplitude of the entire influent flow rate, to construct a basic sequence of pollutant response;

[0109] S4: By identifying the changing trend sequences of ammonia nitrogen and nitrate nitrogen in the basic pollutant response sequence, the point set of overlapping intervals formed by the changing trends of ammonia nitrogen and nitrate nitrogen in the sequence is extracted to obtain the nitrogen resonance response identification results;

[0110] S5: Based on the nitrogen resonance response identification results, identify the associated fluctuation behavior of pollutants and output abnormal fluctuation early warning instructions to obtain the risk early warning results of effluent treatment.

[0111] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A device for treating wastewater from aquaculture, characterized in that, The device includes the following modules: The tailwater parameter extraction module uses an instantaneous flow sensor to detect the oxidation-reduction potential in the tailwater and the instantaneous influent flow rate. Based on the rate of change of the oxidation-reduction potential in the tailwater over a specified time and the relative growth rate of the instantaneous influent flow rate, a set of tailwater flow direction control response parameters is constructed. The flow direction control determination module performs path allocation control based on the normalized ratio of the change rate of oxidation-reduction potential in the tailwater to the relative growth rate of the instantaneous influent flow rate in the tailwater flow direction control response parameter set, and outputs the tailwater path allocation control result. The pollutant data decoupling module obtains continuous data on the synchronous concentrations of ammonia nitrogen and nitrate nitrogen in the effluent, as well as the fluctuation amplitude data of the entire influent flow rate, based on the tailwater path allocation control results, and performs perturbation decoupling to construct a basic pollutant response sequence. The nitrogen resonance identification module identifies the change trend sequences of ammonia nitrogen and nitrate nitrogen in the basic response sequence of the pollutants, extracts the point set of overlapping intervals of the change trends of ammonia nitrogen and nitrate nitrogen in the sequence, and obtains the nitrogen resonance response identification result. The risk warning output module identifies pollutant-related fluctuation behavior and outputs abnormal fluctuation warning commands based on the nitrogen resonance response identification results, thereby obtaining the tailwater treatment risk warning results.

2. The treatment device for aquaculture wastewater according to claim 1, characterized in that, The tailwater flow direction control response parameter set includes the gradient of oxidation-reduction potential changes per unit time, the amplitude of instantaneous influent flow rate changes, and abrupt change points in the sequence of ORP values ​​and time interval ratios of adjacent sampling points. The tailwater path allocation control results include path switching trigger signals, influent direction selection identifiers, and control command timestamps. The pollutant response basic sequence includes ammonia nitrogen change curve nodes, nitrate nitrogen concentration gradient trajectory, and concentration value sequence after disturbance stripping. The nitrogen resonance response identification results include consistency judgment of change trend direction, trend superposition window, and time axis intersection set. The tailwater treatment risk warning results specifically include pollutant linkage risk identifiers, water quality abnormality status labels, and warning response levels.

3. The device for treating aquaculture wastewater according to claim 1, characterized in that, The tailwater parameter extraction module includes: The redox change extraction submodule acquires the time series data of oxidation-reduction potential (ORP) of tailwater collected by the water quality testing equipment, extracts the rate of increase and rate of decrease of data points in the sequence within a set monitoring period, and generates a redox change rate sequence. The flow rate change calculation submodule obtains the instantaneous influent flow data within the time period corresponding to the redox change rate sequence, calculates the relative growth rate of influent flow at continuous time points, and generates an instantaneous flow rate growth rate sequence. The parameter set construction submodule filters synchronously changing time period data based on the time correspondence between the redox change rate sequence and the instantaneous flow rate growth rate sequence to obtain the tailwater flow direction regulation response parameter set.

4. The device for treating aquaculture wastewater according to claim 3, characterized in that, The flow direction control determination module includes: The normalized ratio generation submodule obtains two sets of parameters at the same time node based on the oxidation-reduction potential change rate and the relative growth rate of instantaneous influent flow rate in the tailwater flow direction control response parameter set. After normalizing the two parameters to the 0 to 1 range using the range normalization method, the ratio is calculated to generate a normalized ratio sequence. The transition segment identification submodule selects data from the continuous time period in the normalized ratio sequence, and determines whether the selected segment ratio is in the characteristic interval of the redox boundary by comparing the fluctuation direction of the selected segment ratio with the redox partition threshold change characteristics, thereby obtaining the transition state determination interval. The path control instruction output submodule calls the time point within the transition state determination interval to check whether the time point meets the path switching logic condition. If it does, it is marked as a trigger event segment and the tailrace path allocation control result is generated.

5. The device for treating aquaculture wastewater according to claim 4, characterized in that, The pollutant data decoupling module includes: Based on the tailwater path allocation control results, the concentration data acquisition submodule acquires the continuous concentrations of ammonia nitrogen and nitrate nitrogen in the tailwater obtained by the water quality testing equipment, extracts the numerical changes of each indicator within a fixed period, and establishes ammonia nitrogen concentration sequence and nitrate nitrogen concentration sequence in chronological order to generate a pollutant concentration sequence set. The disturbance impact identification submodule extracts the continuous change data of the influent flow rate within the same time period based on the pollutant concentration sequence set, calculates the amplitude and fluctuation range within each cycle, judges the degree of interference of the flow fluctuation within each time period, and obtains the level of flow disturbance impact. The disturbance signal stripping submodule splits the pollutant concentration sequence set into fluctuation components according to the influence level of the flow disturbance, distinguishes frequency components using ensemble empirical mode decomposition, and extracts the stripped ammonia nitrogen change trend and nitrate nitrogen change trend to obtain the basic pollutant response sequence.

6. The device for treating aquaculture wastewater according to claim 5, characterized in that, The nitrogen-based resonance identification module includes: The trend feature extraction submodule extracts the ammonia nitrogen response sequence and nitrate nitrogen response sequence from the pollutant response base sequence, respectively, extracts the change data of ammonia nitrogen concentration in a continuous time period, calculates the corresponding second-order steering value, identifies the slope change trend of nitrate nitrogen concentration under the same period, and generates trend change feature groups. The change point pairing and identification submodule uses the longest common subsequence algorithm to sequentially compare the trend change direction marker sequences of ammonia nitrogen and nitrate nitrogen based on the trend change feature group, and obtains the time-series key pairing point group; The resonance interval construction submodule calls the time-series key pairing point group, sequentially determines the time span and overlap density between consecutive pairing points, filters the overlap windows that satisfy the direction consistency and sequence continuity, and establishes the nitrogen-type resonance response identification results.

7. The device for treating aquaculture wastewater according to claim 6, characterized in that, The risk warning output module includes: The synchronous window extraction submodule extracts the timestamp data of ammonia nitrogen trend change points and nitrate nitrogen change points based on the nitrogen resonance response identification results, compares the time positions of the two types of change points, filters point groups within the overlapping time range, and generates a synchronous change window set. The trend judgment submodule calls the response direction of each point group in the synchronous change window set, compares the change direction of ammonia nitrogen with the change direction of nitrate nitrogen one by one, judges whether the directions are consistent, calculates the proportion of consistent directions among all effective change pairs, and obtains the trend consistency rate. The instruction information generation submodule determines whether the response threshold is exceeded based on the consistency rate of the change trend. If it is, it is marked as a warning state segment, the corresponding time and type are recorded, a pollutant fluctuation warning instruction is generated, and the tailwater treatment risk warning result is obtained.

8. A method for treating wastewater from aquaculture, characterized in that, The apparatus for treating aquaculture wastewater according to any one of claims 1-7 comprises the following steps: S1: By detecting the oxidation-reduction potential and instantaneous influent flow rate in the effluent, and based on the rate of change of the oxidation-reduction potential in the effluent over a specified time and the relative growth rate of the instantaneous influent flow rate, a set of effluent flow direction control response parameters is constructed. S2: Based on the normalized ratio of the rate of change of oxidation-reduction potential in the tailwater to the relative growth rate of the instantaneous influent flow rate in the tailwater flow direction control response parameter set, determine whether the current influent is in the transition zone between oxidation-reduction states, and output the tailwater path allocation control result based on the judgment result. S3: Perform perturbation decoupling on the continuous data of synchronous concentrations of ammonia nitrogen and nitrate nitrogen in the effluent, as well as the data of fluctuation amplitude of the entire influent flow rate, to construct a basic sequence of pollutant response; S4: By identifying the change trend sequences of ammonia nitrogen and nitrate nitrogen in the basic response sequence of the pollutants, the point set of overlapping intervals of the change trends of ammonia nitrogen and nitrate nitrogen in the sequence is extracted to obtain the nitrogen resonance response identification result; S5: Based on the nitrogen resonance response identification results, identify the pollutant-related fluctuation behavior and output abnormal fluctuation warning instructions to obtain the tailwater treatment risk warning results.

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