A deep treatment device and method for dyeing and printing wastewater

Abstract

This invention specifically relates to a deep treatment device and method for dyeing and printing wastewater. The device includes a pretreatment unit, an electrolysis unit, a pH adjustment unit, a post-treatment unit, and a comprehensive monitoring unit. The pretreatment unit includes a physical filtration device and an advanced oxidation pretreatment device for removing suspended solids and macromolecular organic matter. The electrolysis unit is equipped with a current control module and a salinity adjustment module for degrading organic pollutants and disinfecting. The pH adjustment unit is equipped with a pH sensor and a pH correction pump for precisely controlling pH changes during the treatment process. The post-treatment unit includes an ultrafiltration membrane and activated carbon for removing residual small molecule organic matter and trace heavy metal ions. The comprehensive monitoring unit integrates a PLC controller, a data acquisition module, and a communication interface for automated management and remote monitoring of the system.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment, specifically relating to a deep treatment device and method for dyeing and printing wastewater. Background Technology

[0002] The dyeing and printing industry is one of the sectors with the largest water consumption and wastewater discharge. The wastewater generated during its production process contains a large amount of pollutants such as organic matter, dyes, auxiliaries, and heavy metal ions that are difficult to biodegrade. This type of wastewater typically has the following characteristics:

[0003] High chromaticity: Due to the presence of various dyes, wastewater often exhibits a dark color, causing visual pollution to the aquatic environment.

[0004] Complex composition: In addition to dyes, it also contains a variety of chemical additives, such as surfactants and fixing agents, which increases the difficulty of processing.

[0005] High COD / BOD ratio: High chemical oxygen demand (COD) and biochemical oxygen demand (BOD) indicate that the wastewater is rich in organic matter and requires effective removal methods.

[0006] High salt content: Some dyeing and printing processes use a large amount of salt, which increases the conductivity of wastewater and affects subsequent treatment processes.

[0007] Traditional methods for treating dyeing and printing wastewater mainly include physical methods (such as sedimentation and filtration), chemical methods (such as coagulation and oxidation-reduction), and biological methods (such as activated sludge processes). However, these methods have limitations when applied individually, such as low treatment efficiency, high operating costs, and the risk of secondary pollution. With increasingly stringent environmental regulations and growing public awareness of environmental protection, developing a highly efficient, economical, and environmentally friendly advanced treatment technology for dyeing and printing wastewater is of paramount importance.

[0008] Currently, although various dyeing and printing wastewater treatment technologies are widely used, some challenges still exist:

[0009] Unstable treatment results: Traditional treatment processes have limited adaptability to the complex and ever-changing composition of dyeing and printing wastewater, especially when faced with sudden changes in water quality, making it difficult to guarantee stable treatment results.

[0010] High energy and chemical consumption: In order to achieve higher purification standards, many treatment systems have to increase the amount of chemicals used or increase electricity consumption, which not only increases operating costs but also brings new environmental pollution problems.

[0011] Low level of automation: Some existing processing equipment lacks intelligent management functions and relies heavily on manual intervention in operation and maintenance, which can easily lead to misoperation or delayed response, thus affecting the overall processing efficiency.

[0012] Low resource recycling rate: Some treatment processes fail to fully consider the recycling of resources, such as the recovery and reuse of useful substances in wastewater, resulting in resource waste.

[0013] In response to the above problems, there is an urgent need in the market for a new generation of advanced treatment equipment and methods for dyeing and printing wastewater that can overcome the shortcomings of existing technologies. Summary of the Invention

[0014] The purpose of this invention is to provide a deep treatment device for dyeing and printing wastewater, and another purpose of this invention is to provide a deep treatment method for dyeing and printing wastewater, so as to solve the problems mentioned in the background art.

[0015] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0016] A deep treatment device for dyeing and printing wastewater includes a pretreatment unit, an electrolysis unit, a pH adjustment unit, a post-treatment unit, and a comprehensive monitoring unit. The pretreatment unit includes a physical filtration device and an advanced oxidation pretreatment device for removing suspended solids and macromolecular organic matter. The electrolysis unit is equipped with a current control module and a salinity adjustment module for degrading organic pollutants and disinfecting. The pH adjustment unit is equipped with a pH sensor and a pH correction pump for precisely controlling pH changes during the treatment process. The post-treatment unit includes an ultrafiltration membrane and activated carbon for removing residual small molecule organic matter and trace heavy metal ions. The comprehensive monitoring unit integrates a PLC controller, a data acquisition module, and a communication interface for automated management and remote monitoring of the system.

[0017] Furthermore, the pretreatment unit includes a pretreatment tower, which comprises a grid, a sand filter, and a microfiltration mesh arranged from top to bottom. The upper part of the grid is provided with a dyeing and printing wastewater inlet. The upper part of the sand filter is provided with several flexible high-pressure flushing spray heads. The bottom of the sand filter is provided with a pressure sensor. The lower part of the microfiltration mesh is provided with a conical filter bucket. The conical filter bucket has a spiral outlet at its conical opening. The spiral outlet has a spiral baffle. The filtrate enters the oxidation tank at the bottom along the spiral baffle. The oxidation tank includes an ozone tube at the bottom. The ozone tube has several microporous aeration heads. The oxidation tank also has a turbine mixer above the ozone tube. The upper part of the oxidation tank also has a catalyst addition pump, a waste gas collection port, and an ORP sensor. The oxidation tank also integrates an ultraviolet lamp.

[0018] The control valve and pressure sensor of the flexible high-pressure flushing spray head are electrically connected to the PLC controller. When the pressure value detected by the pressure sensor under the sand filter exceeds the preset threshold, the PLC controller triggers the flexible high-pressure flushing spray head to flush the sand filter. The ORP sensor and the flow control valve of the ozone tube are electrically connected to the PLC controller. The PLC controller has a preset ORP range. When the ORP sensor detects that the ORP value deviates from the set range, the PLC controller adjusts the flow control valve of the ozone tube.

[0019] Furthermore, the electrolysis unit includes an electrolytic cell. The oxidation tank of the pretreatment tower is connected to the electrolytic cell via a pipeline. A water pump and a control valve are installed on the pipeline connecting the pretreatment tower and the electrolytic cell. The upper part of the electrolytic cell is provided with an inlet for wastewater to be electrolyzed. A pipeline is connected to the inlet of the wastewater to be electrolyzed in the electrolytic cell. The electrolytic cell includes an anode electrode and a cathode electrode. A salinity correction pump is connected to one side of the electrolytic cell and is equipped with a corresponding solenoid valve. Several COD sensors and salinity sensors are also installed inside the electrolytic cell.

[0020] Furthermore, the COD sensor is electrically connected to the PLC controller. The PLC controller uses its built-in data processing module to analyze the received COD signal and predict the required current density adjustment range based on the water quality change trend. Specifically, the prediction of the required current density adjustment range based on the water quality change trend utilizes a long short-term memory network algorithm for adaptive control. The specific steps include:

[0021] Collect and organize historical data, including COD concentration, temperature, and pH value, and normalize the data.

[0022] The data is divided into training and test sets. 70% of the data is used as the training set and 30% of the data is used as the test set to construct time series samples. For each time point t, the data of the past n time points are used as input and the optimal current intensity at time t is used as the label.

[0023] The LSTM model is trained using the training set, and the loss function is minimized through the backpropagation algorithm to adjust the hyperparameters.

[0024] Evaluate the model's performance on the test set, calculate the error between the predicted and actual values, and adjust the model structure or parameters based on the evaluation results.

[0025] The trained LSTM model is deployed to the PLC controller to receive data from the sensors in real time, predict and output the optimal current intensity;

[0026] To achieve closed-loop control, the current output is dynamically adjusted based on the prediction results, while new data is continuously collected for online learning and model updates.

[0027] The PLC controller dynamically adjusts the current output based on the received real-time COD data and the preset optimal current range. When the COD concentration is below the set threshold, the PLC will trigger the energy-saving mode to reduce the current intensity; otherwise, it will increase the current density.

[0028] Furthermore, the solenoid valves corresponding to the salinity sensor and the salinity correction pump are electrically connected to the PLC controller. The PLC controller reads the data from the salinity sensor at regular intervals. If the salinity is found to be lower or higher than the ideal range, the PLC controller immediately starts the correction program and adds an appropriate amount of sodium chloride solution through the salinity correction pump to bring the salinity back to the set range.

[0029] Furthermore, the pH adjustment unit includes a pH correction pump installed on one side of the electrolytic cell. The pH correction pump is equipped with a corresponding solenoid valve. The electrolytic cell is also equipped with several pH sensors and several first ultrasonic cleaners. The solenoid valve and pH sensor corresponding to the pH correction pump are electrically connected to the PLC controller. The PLC controller calculates the amount of acid or alkali solution to be added based on the data fed back by the pH sensor and outputs control commands to the pH correction pump.

[0030] Furthermore, the post-treatment unit includes a post-treatment tank. The bottom of the electrolytic cell is connected to the post-treatment tank via a pipe and a post-treatment water pump. The post-treatment tank is equipped with a vertical UF membrane and an activated carbon filter layer. A second ultrasonic cleaner is provided at the front end of the UF membrane. A water quality detection port and a drain port are provided on the side of the post-treatment tank corresponding to the activated carbon filter layer.

[0031] A method for deep treatment of dyeing and printing wastewater includes the following steps:

[0032] S1. Pretreatment stage: The dyeing and printing wastewater passes through the pretreatment tower and is filtered by a bar screen, sand filter and micro-filter to remove suspended particulate matter. After multi-stage filtration, the wastewater enters the oxidation tank for oxidation reaction. The oxidation-reduction potential is monitored in real time using an ORP sensor to automatically adjust the ozone supply.

[0033] S2 Electrolysis Treatment Stage: The pretreated wastewater is pumped into the electrolysis cell, and an electric current is applied between the anode and cathode. An online COD sensor monitors water quality changes in real time, and the current output parameters are dynamically adjusted by combining a long short-term memory network algorithm. The sodium chloride content in the wastewater is adjusted by a salinity correction pump to ensure suitable electrolysis conditions.

[0034] S3. pH adjustment stage: The pH value of the wastewater is monitored in real time using an online pH sensor. The pH correction pump accurately adds an appropriate amount of acid or alkali solution based on the feedback data to keep the pH value within the target range.

[0035] S4. Post-treatment stage: Wastewater is purified through a UF membrane and activated carbon filter layer. The water quality testing port is equipped with an online water quality analyzer to monitor the effluent water quality indicators in real time, ensuring that the water meets the discharge standards or is reused.

[0036] Beneficial Effects: This application provides a highly efficient, intelligent, and environmentally friendly advanced treatment device and method for dyeing and printing wastewater, achieving effective removal and purification of various pollutants in the wastewater. Its main technical effects are as follows:

[0037] 1. Highly efficient multi-stage preprocessing

[0038] Removal of suspended solids and macromolecular organic matter: The multi-stage filtration system, consisting of a screen, sand filter, and microfiltration mesh, effectively removes suspended particles of different sizes, providing a stable water quality input for subsequent treatment.

[0039] Automatic backwashing mechanism: High-precision pressure sensors monitor differential pressure in real time, and the PLC controller automatically starts the backwashing program according to the set threshold to prevent filter media from clogging, ensure continuous and stable filtration effect, and reduce the need for manual maintenance.

[0040] 2. Enhanced advanced oxidation pretreatment

[0041] Ozone oxidation tower: It adopts countercurrent contact, turbulent contact and other methods to make ozone gas fully dissolve in wastewater and enhance the oxidation reaction rate; combined with UV light and specific catalysts (such as titanium dioxide TiO2), it further enhances the oxidation reaction rate and significantly reduces the concentration of organic pollutants.

[0042] Dynamic air intake adjustment: The ORP sensor monitors the oxidation-reduction potential in real time and automatically adjusts the ozone supply to maintain optimal oxidation conditions. At the same time, the exhaust gas collection port ensures the safety and environmental friendliness of the operating environment.

[0043] 3. Intelligent electrolysis treatment

[0044] Degrading organic pollutants and disinfecting: Modified graphene-based composite materials are used as anodes to enhance electrochemical reaction efficiency; combined with a long short-term memory network algorithm (LSTM) to implement an adaptive current control strategy, dynamically responding to water quality fluctuations and automatically optimizing current output parameters to ensure optimal treatment results under different load conditions.

[0045] Salinity control module: Built-in salinity sensor accurately measures sodium chloride content to ensure suitable electrolysis conditions and avoid the risk of byproduct formation.

[0046] 4. Precise pH adjustment

[0047] Online pH monitoring and correction: A highly sensitive online pH sensor is used to monitor the pH changes in wastewater in real time. The pH correction pump accurately adds the appropriate amount of acid or alkali solution based on the feedback data to maintain the pH value within the target range (e.g., 6.0 to 8.5), ensuring the stability and effectiveness of the treatment process.

[0048] 5. Optimization of the post-processing unit

[0049] Removal of residual pollutants: The UF membrane and activated carbon filter layer effectively remove residual small molecule organic matter and trace heavy metal ions, ensuring that the final effluent quality meets the standards for discharge or reuse; the ultrasonic cleaner works regularly to prevent membrane surface fouling and clogging, extending the service life of the equipment.

[0050] Intelligent Management System: The PLC controller manages the post-processing unit in a unified manner, receives data from various sensors, automatically starts cleaning or regeneration programs, and issues regeneration or replacement prompts in advance to ensure the reliability and stability of the system.

[0051] 6. Integrated monitoring and remote management

[0052] Automated management and remote monitoring: The PLC controller, as the core control unit, is responsible for receiving data from various sensors and issuing control commands to the actuators according to preset algorithms; it supports remote access and management, allowing managers to monitor the system's operating status anytime, anywhere, receive alarm information, and respond promptly.

[0053] Data security and compliance: SSL / TLS encryption technology is used during communication to ensure the security and integrity of data transmission; the system automatically records all operation logs, alarm events and handling actions to form a complete activity track, which facilitates fault diagnosis and accountability, ensures compliance with regulatory requirements, and improves the company's compliance management level.

[0054] In summary, the advanced treatment equipment and method for dyeing and printing wastewater provided in this application demonstrate superior technical performance, rapidly responding to different water quality conditions and maintaining stable treatment results, while also meeting the requirements of energy conservation and environmental protection. This advanced treatment method not only enhances the intelligent management level of the system but also improves the reliability and environmental performance of the entire dyeing and printing wastewater treatment equipment, significantly reducing operating costs and maintenance difficulties, achieving a win-win situation for both economic and environmental benefits. Attached Figure Description

[0055] Figure 1 This is a schematic diagram of the system connection of the present invention.

[0056] In the diagram, 100. Pretreatment tower, 101. Grille, 102. Sand filter, 103. Microfiber filter, 104. Conical filter, 105. Dyeing and printing wastewater inlet, 106. Flexible high-pressure flushing spray head, 107. Pressure sensor, 108. Spiral outlet, 109. ORP sensor, 110. Catalyst addition pump, 111. Exhaust gas collection port, 112. Turbine mixer, 113. Ozone tube, 114. Microporous aerator;

[0057] 200. Electrolytic cell; 201. Anode electrode; 202. Cathode electrode; 203. Salinity correction pump; 204. COD sensor; 205. Water pump; 206. Control valve; 207. Wastewater inlet to be electrolyzed; 208. pH correction pump; 209. pH sensor; 210. First ultrasonic cleaner; 211. Salinity sensor.

[0058] Post-treatment tank, 301. Post-treatment water pump, 302. UF membrane, 303. Activated carbon filter layer, 304. Second ultrasonic cleaner, 305. Water quality test port, 306. Drain outlet. Detailed Implementation

[0059] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0060] A deep treatment device for dyeing and printing wastewater includes a pretreatment unit, an electrolysis unit, a pH adjustment unit, a post-treatment unit, and a comprehensive monitoring unit. The pretreatment unit includes a physical filtration device and an advanced oxidation pretreatment device for removing suspended solids and macromolecular organic matter. The electrolysis unit is equipped with a current control module and a salinity adjustment module for degrading organic pollutants and disinfecting. The pH adjustment unit is equipped with a pH sensor and a pH correction pump for precisely controlling pH changes during the treatment process. The post-treatment unit includes an ultrafiltration membrane and activated carbon for removing residual small molecule organic matter and trace heavy metal ions. The comprehensive monitoring unit integrates a PLC controller, a data acquisition module, and a communication interface for automated management and remote monitoring of the system.

[0061] like Figure 1As shown, the pretreatment unit includes a pretreatment tower 100, which includes a grid 101, a sand filter 102, and a microfiltration membrane 103 arranged from top to bottom. The upper part of the grid 101 is provided with a dyeing and printing wastewater inlet 105. The upper part of the sand filter 102 is provided with several flexible high-pressure flushing spray heads 106, and the bottom of the sand filter 102 is provided with a pressure sensor 107. The lower part of the microfiltration membrane 103 is provided with a conical filter bucket 104, and the conical opening of the conical filter bucket 104 is equipped with a screw... The spiral outlet 108 has a spiral baffle inside, and the filtrate enters the bottom oxidation tank along the spiral baffle. The oxidation tank includes an ozone tube 113 at the bottom, and the ozone tube 113 is provided with several microporous aeration heads 114. The oxidation tank is also provided with a turbine mixer 112 above the ozone tube 113. The upper part of the oxidation tank is also provided with a catalyst addition pump 110, a waste gas collection port 111, and an ORP sensor 109. The oxidation tank is also integrated with an ultraviolet lamp.

[0062] The main task of the pretreatment unit is to remove suspended solids and large molecular organic pollutants from wastewater, providing a stable water quality input for subsequent treatment. The configuration includes:

[0063] Multi-stage filtration system: including coarse filter screen 101, fine sand filter 102, and microfiltration mesh 103. Each stage of filtration targets suspended particulate matter of different sizes, purifying it progressively from large to small.

[0064] Swirl-flow inlet: This includes a conical filter 104 with a spiral outlet 108 at its conical opening. The spiral outlet 108 contains a spiral baffle. The spiral baffle creates a swirling flow as the filtrate enters the oxidation tank, distributing the liquid more evenly in the inlet area. This helps ensure sufficient contact between ozone and pollutants in the wastewater, improving reaction efficiency. The swirling flow allows for initial gas-liquid mixing as the wastewater enters the oxidation tank (especially if ozone gas from the ozone tube 113 is already present), initiating the oxidation process earlier and increasing treatment effectiveness. The conical filter design, combined with the spiral outlet, allows pre-treated wastewater to enter the oxidation tank more gently, avoiding direct impact on bottom structures or equipment, such as the microporous aerator heads 114 on the ozone tube, extending equipment lifespan. The conical structure facilitates the collection of any large particles or sediments that fail to filter out at the bottom of the filter, making subsequent cleaning or removal from the system easier and preventing these substances from entering the oxidation tank and affecting treatment efficiency. The spiral baffle alters the water flow path, increasing the path length of water before entering the oxidation tank. This provides additional time for some light suspended solids to settle or adhere to the baffle, thus acting as an auxiliary filter. This design better prepares the wastewater for the next stage of advanced oxidation treatment, ensuring the effectiveness and stability of the treatment process.

[0065] Automatic backwashing mechanism: The system features an automatic backwashing function triggered by timed intervals or differential pressure to prevent filter media clogging, ensure consistent and stable filtration performance, and reduce manual maintenance requirements. A high-precision pressure sensor 107 is installed at the bottom or outlet of the sand filter 102 to monitor the filtered water pressure in real time. This sensor boasts high sensitivity and stability, accurately detecting minute pressure changes. Data from the pressure sensor 107 is transmitted to the PLC controller via dedicated signal cables. These cables are typically waterproof and corrosion-resistant, ensuring long-term stable operation. The PLC controller, as the core of the system, receives data from the pressure sensor 107 and makes judgments based on preset thresholds. If the detected differential pressure exceeds a set value, such as 0.5 bar, the PLC immediately initiates the backwashing program. A reasonable differential pressure threshold is preset in the PLC; this value can be adjusted according to actual operating conditions and water quality characteristics to ensure optimal backwashing effect and frequency. Sufficient water pressure is provided by a dedicated high-pressure water pump or accumulator to ensure that the flexible high-pressure flushing spray head 106 can generate a sufficiently strong water flow to remove impurities adhering to the filter media. The flexible high-pressure flushing spray head 106 begins operation, spraying high-pressure water into the sand filter 102. The flexible design of the spray head allows for flexible adjustment of the spray angle and coverage area, ensuring comprehensive cleaning. In practice, even if the differential pressure threshold is not reached, the PLC can periodically initiate backwashing according to a preset schedule to prevent potential clogging.

[0066] Advanced oxidation pretreatment: The ozone oxidation tower employs highly efficient gas-water contact methods, including countercurrent and turbulent contact, to ensure ozone gas is fully dissolved in the wastewater and enhance the oxidation reaction rate. The tower is equipped with multiple layers of packing or a dedicated gas-liquid distributor. Wastewater flows downwards from the top of the tower, while ozone gas is sprayed upwards from the bottom, forming a countercurrent contact mode. This countercurrent approach increases the contact time and area between the gas and liquid phases, improving ozone transfer efficiency. A specially designed turbulence generator, such as a turbine mixer 112, is installed to induce intense turbulence in the water flow, increasing the mixing degree. Microporous aerators 114 decompose ozone gas into fine bubbles, increasing the total surface area of ​​the bubbles and promoting the exchange of substances between the gas and water.

[0067] Dynamic air intake adjustment: Equipped with an online monitoring instrument, the ORP sensor 109, monitors ozone concentration and oxidation-reduction potential in real time, automatically adjusting the ozone supply to maintain optimal oxidation conditions. The ORP sensor 109 is installed at the top of the oxidation tank to monitor the oxidation-reduction potential (ORP) in the wastewater in real time. This sensor features high sensitivity and rapid response, accurately reflecting ozone dissolution and oxidation capacity. Data from the ORP sensor is transmitted to the PLC controller via dedicated signal cables, which are typically waterproof and corrosion-resistant to ensure long-term stable operation. The PLC controller, as the core of the entire system, receives data from the ORP sensor 109 and makes judgments based on the preset optimal ORP range. If the detected ORP value deviates from the set range, the PLC immediately initiates the adjustment program. Based on instructions from the PLC controller, the operating parameters of the ozone generator, such as frequency and power, are automatically adjusted to change the ozone production rate to meet real-time requirements. A precision flow control valve is installed at the inlet of the ozone gas pipe 113 to ensure precise and controllable ozone gas flow into the oxidation tank, while also featuring a leak-proof design for safety. Using microporous aerators 114 or other advanced aeration equipment, ozone gas is decomposed into tiny bubbles, increasing the total surface area of ​​the bubbles and further promoting the exchange of substances between air and water.

[0068] Assisted catalysis: In conjunction with UV irradiation, UV lamps are integrated inside the tower to excite ozone molecules and accelerate the generation of free radicals; specific catalysts such as titanium dioxide (TiO2) are added through catalyst addition pump 110 to enhance the oxidation reaction rate.

[0069] Waste gas treatment facilities: Add dedicated waste gas collection and treatment devices to ensure the safety and environmental friendliness of the operating environment.

[0070] The electrolysis unit includes an electrolytic cell 200. The oxidation tank of the pretreatment tower 100 is connected to the electrolytic cell 200 via a pipeline. A water pump 205 and a control valve 206 are installed on the pipeline connecting the pretreatment tower 100 and the electrolytic cell 200. The upper part of the electrolytic cell 200 is provided with a wastewater inlet 207 to be electrolyzed. A pipeline is connected to the wastewater inlet 207 of the electrolytic cell 200. The electrolytic cell 200 includes an anode electrode 201 and a cathode electrode 202. A salinity correction pump 203 is connected to one side of the electrolytic cell 200 and is equipped with a corresponding solenoid valve. Several COD sensors 204 are also installed inside the electrolytic cell 200.

[0071] The electrolysis unit is equipped with a current control module and a salinity adjustment module for degrading organic pollutants and disinfecting.

[0072] The electrolysis unit uses a modified graphene-based composite material with high conductivity and large specific surface area as the anode 201. This material significantly improves electrochemical reaction efficiency while possessing good corrosion resistance and stability, extending the electrode's service life. Surface modification of graphene by introducing nanoscale metal oxides or noble metal particles such as iridium dioxide (IrO2) and platinum (Pt) enhances its catalytic activity, further promoting the degradation of organic pollutants. Stainless steel is used as the cathode 202, which is not only cost-effective but also possesses good mechanical strength and corrosion resistance, making it suitable for long-term operating environments. To prevent passivation or corrosion of the stainless steel during long-term use, a protective coating, such as a titanium-based coating, is applied to its surface to improve its corrosion resistance and maintain efficient electron conduction. The anode 201 and cathode 202 are vertically mounted on both sides of the electrolytic cell and fixed inside the cell by corrosion-resistant supports. Sufficient space is left at the bottom to allow for smooth water flow, ensuring uniform current distribution and maximizing the reaction area.

[0073] The electrolysis unit is equipped with an adaptive current control module. A high-precision online chemical oxygen demand (COD) sensor 204 is installed near the inlet to monitor the wastewater quality before it enters the electrolyzer in real time, continuously monitoring changes in the concentration of organic matter in the wastewater. The COD sensor 204 is electrically connected to a PLC controller. The PLC controller uses its built-in data processing module to quickly analyze the received COD signal and predict the required current density adjustment range based on the water quality change trend.

[0074] The electrolysis unit is equipped with an adaptive control strategy based on a long short-term memory network algorithm. This strategy can dynamically respond to water quality fluctuations and automatically optimize current output parameters to ensure optimal treatment results under different load conditions. Specifically, the technical goal is to automatically switch to energy-saving mode when the influent chemical oxygen demand (COD) concentration is low, reducing current intensity and unnecessary energy consumption; conversely, when COD increases, the current density is rapidly increased to ensure treatment efficiency. The technical implementation includes:

[0075] Online COD Sensor 204: High-precision online chemical oxygen demand (COD) sensors are installed to monitor the wastewater quality in real time before it enters the electrolyzer. These sensors feature high sensitivity and fast response, ensuring data accuracy. Data from the COD sensors is transmitted to the PLC controller via dedicated signal cables. These cables are typically waterproof and corrosion-resistant, ensuring long-term stable operation.

[0076] Built-in data processing module: The PLC controller integrates a data processing module for rapid analysis of received COD signals. This module can predict the required current density adjustment range based on water quality change trends and provide a basis for subsequent intelligent regulation decisions.

[0077] Historical data analysis: The built-in storage module stores long-term historical data, and big data analysis technology is used to predict future water quality changes, adjust operating parameters in advance, and avoid lag effects.

[0078] Adaptive Control Algorithm: Based on a Long Short-Term Memory (LSTM) network algorithm, this adaptive control strategy dynamically responds to water quality fluctuations and automatically optimizes current output parameters. This algorithm can continuously self-optimize based on historical data, improving prediction accuracy and response speed. The model structure includes an input layer, hidden layers, and an output layer. The input layer's input features include historical COD concentration values, current COD concentration, temperature, and pH values—factors that may affect the electrolysis process. For example, the input could be the hourly COD concentration over the past 24 hours, forming a 24-hour time series. The hidden layer contains multiple LSTM units, each responsible for processing one time step in the time series. Each LSTM unit contains forget gates, input gates, and output gates; these gating mechanisms allow the network to selectively remember or forget information, effectively handling long-term dependencies. Multiple LSTM layers are used to increase the model's complexity and expressive power. The output layer predicts the optimal current intensity over a future period. If the goal is immediate adjustment, the output can directly correspond to the optimal current value for the next time step; if the goal is advance planning, it can output the current plan for several future time steps. The specific steps of adaptive control using the LSTM network algorithm include:

[0079] Collect and organize historical data, including COD concentration, temperature, and pH value, and normalize the data to ensure that all feature values ​​are within the same order of magnitude, which facilitates training.

[0080] The data is divided into training and testing sets. 70% of the data is used as the training set and 30% as the testing set to construct time series samples. For each time point t, the data from the past n time points are used as input, and the optimal current intensity at time t is used as the label.

[0081] The LSTM model is trained using the training set, the loss function is minimized using the backpropagation algorithm, and the hyperparameters are adjusted to improve model performance.

[0082] Evaluate the model's performance on the test set, calculate the error between the predicted and actual values, and further adjust the model structure or parameters based on the evaluation results.

[0083] The trained LSTM model is deployed into the PLC controller to receive data from sensors in real time, predict and output the optimal current intensity. This achieves closed-loop control, dynamically adjusting the current output based on the prediction results while continuously collecting new data for online learning and model updates.

[0084] The PLC controller dynamically adjusts the current output based on the received real-time COD data and a preset optimal current range. For example, when the COD concentration is below a set threshold, the PLC will trigger an energy-saving mode to reduce the current intensity; conversely, it will increase the current density to ensure processing efficiency.

[0085] The above model enables adaptive switching between energy-saving mode and high-efficiency processing mode:

[0086] In energy-saving mode, when the PLC controller detects that the influent COD concentration remains at a consistently low level, it automatically switches to energy-saving mode. In this mode, the current intensity is reduced to the minimum level required to maintain basic functions, thereby significantly reducing energy consumption.

[0087] In high-efficiency treatment mode, once an increase in COD concentration is detected, especially exceeding the set threshold, the PLC immediately switches back to high-efficiency treatment mode, rapidly increasing the current density to ensure that organic pollutants are fully degraded. This process is seamless and rapid, addressing the challenges posed by changes in water quality.

[0088] In practical applications, this adaptive current control strategy has demonstrated its superior performance:

[0089] Highly adaptable: Whether it is seasonal changes or water quality fluctuations caused by sudden events, the system can respond quickly and maintain stable treatment results.

[0090] Energy saving and emission reduction: By precisely controlling the current output, not only is the processing efficiency improved, but power consumption is also significantly reduced, achieving a win-win situation for both economic and environmental benefits.

[0091] Easy to maintain: The intelligent management system reduces the need for manual intervention, simplifies daily maintenance, and lowers operating costs.

[0092] In summary, the adaptive control strategy developed based on machine learning algorithms provides strong technical support for the electrolysis unit, ensuring optimal treatment results under different water quality conditions while also meeting the requirements of energy conservation and environmental protection. This advanced control method not only enhances the system's intelligent management level but also improves the reliability and environmental performance of the entire advanced dyeing and printing wastewater treatment equipment.

[0093] The electrolysis unit is also equipped with a precise salinity control module, including a built-in salinity sensor 211 (a high-resolution sensor for accurately measuring sodium chloride content), a salinity correction pump 203 for adding an appropriate amount of sodium chloride solution, and a safety protection module including an over-limit warning mechanism and an emergency response plan. Equipped with the high-resolution salinity sensor 211, it can accurately measure the sodium chloride content in wastewater, ensuring it is maintained within the ideal range of 0.005 mol / L to 0.05 mol / L. If the salinity deviates from the set range, the system will immediately initiate a correction procedure, adding an appropriate amount of sodium chloride solution to restore the correct salinity level, thereby avoiding the risk of byproduct formation. A salinity upper limit alarm threshold is set; if this limit is exceeded, the system will issue an alarm to remind operators to take appropriate measures to prevent equipment damage or other safety hazards caused by excessive salinity. The salinity correction pump 203 is connected to the inside of the electrolysis cell via corrosion-resistant piping. A feedback loop is established between the salinity sensor 211 and the correction pump 203 to achieve automatic adjustment. Specifically, the setup steps are as follows:

[0094] When the system starts up, the PLC controller reads the current salinity value and checks whether it is within the preset ideal range of 0.005mol / L to 0.05mol / L.

[0095] The PLC controller reads the data from the salinity sensor 211 at regular intervals, such as every minute, to ensure real-time monitoring of salinity changes.

[0096] If the salinity is found to be below or above the ideal range, the PLC controller immediately starts the correction program, adding an appropriate amount of sodium chloride solution through the salinity correction pump 203 to bring the salinity back to the set range.

[0097] If the salinity exceeds the set upper alarm threshold, such as 0.06 mol / L, the PLC controller will trigger an alarm to notify the operator and execute predefined safety measures, such as suspending water intake or activating emergency drainage.

[0098] The system records all salinity measurements and correction actions, generating log files for subsequent analysis and auditing. It also regularly generates reports for administrators to help them understand the system's operational status.

[0099] The pH adjustment unit is equipped with an online pH sensor 209 and a pH calibration pump 208, used to detect and add appropriate amounts of acid or alkali solutions to ensure the pH remains within the target range throughout the treatment process, reducing chemical usage and precisely controlling pH changes during treatment. The highly sensitive, fast-response online pH sensor 209 monitors pH changes in wastewater in real time, ensuring data accuracy and timeliness. The online pH sensor 209 is typically installed near the inlet or outlet of the electrolysis unit to promptly capture pH trends. It is installed using either an insertion or flow-through method, ensuring the sensor probe is completely submerged in the wastewater with stable, undisturbed water flow. The pH calibration pump 208 is installed in an easily accessible location for convenient daily inspection and maintenance, generally located inside or near the pH adjustment unit. It is directly connected to the wastewater channel via corrosion-resistant piping, ensuring that added chemicals are quickly and evenly mixed into the wastewater. The sensor is equipped with an ultrasonic self-cleaning device to prevent dirt buildup from affecting measurement accuracy and reducing maintenance frequency. An integrated intelligent control system automatically calculates and precisely adds appropriate amounts of acid or alkali solution based on data from the pH sensor 209 to maintain a target pH range, such as 6.0–8.5. The PLC controller receives data from the pH sensor 209 and outputs control commands to the pH correction pump 208 using a preset algorithm. The specific operation process is as follows:

[0100] When the system starts up, the PLC controller reads the current pH value and checks whether it is within the preset target range, such as 6.0 to 8.5.

[0101] The PLC controller reads data from the pH sensor 209 at regular intervals, such as every minute, to ensure real-time monitoring of pH changes.

[0102] If the pH value is found to deviate from the target range, the PLC controller immediately starts the calibration program, adding an appropriate amount of acid or alkali solution through the pH calibration pump 208 to restore the pH value to the set range.

[0103] The operating parameters of the pH correction pump 208, such as flow rate and frequency, are dynamically adjusted by the PLC according to the PID control algorithm to ensure accurate addition.

[0104] Set upper and lower pH alarm thresholds, such as 5.5 and 8.8. Once these limits are exceeded, the PLC will trigger an alarm to notify the operator and execute predefined safety measures, such as suspending water intake or activating emergency drainage.

[0105] The system records all pH measurements and calibration actions, generating log files for subsequent analysis and auditing. It also regularly generates reports for administrators to help them understand the system's operational status.

[0106] Post-processing unit

[0107] To ensure that the post-treatment unit of the advanced treatment equipment for dyeing and printing wastewater can effectively remove residual small-molecule organic matter and trace heavy metal ions, while also guaranteeing the system's automated management and remote monitoring capabilities, the following are the specific implementation details:

[0108] The post-treatment unit includes a post-treatment tank 300. The bottom of the electrolysis tank 200 is connected to the post-treatment tank 300 via a pipe and a post-treatment water pump 301. The post-treatment tank 300 contains a vertical UF membrane 302 and an activated carbon filter layer 303. A second ultrasonic cleaner 304 is installed at the front end of the UF membrane 302 to prevent membrane surface fouling and clogging. The ultrasonic cleaner operates periodically, using high-frequency vibration to break down contaminants adhering to the membrane surface, maintaining good permeability. A water quality testing port 305 and a drain outlet 306 are located on the side of the post-treatment tank 300 corresponding to the activated carbon filter layer 303. The water quality testing port 305 is equipped with an online water quality analyzer, such as a conductivity meter and turbidity meter, to monitor the effluent water quality indicators in real time, ensuring that the water meets discharge or reuse standards. The drain outlet 306 is located at the bottom of the post-treatment tank and is controlled by a valve to ensure that only fully treated and qualified water is discharged from the system. If the water quality does not meet the standards, a circulation treatment process is initiated until the discharge standards are met. The post-treatment unit is centrally managed by a PLC controller, receiving data from various sensors, including UF membrane differential pressure, pressure difference before and after the activated carbon layer, and various parameters at the water quality monitoring port. When the UF membrane differential pressure exceeds a set threshold, the PLC controller automatically starts the ultrasonic cleaner 304 and checks whether the pressure difference has returned to normal after cleaning. Based on the trend of pressure difference changes before and after the activated carbon filter layer, the PLC predicts the activated carbon saturation level and issues a regeneration or replacement prompt in advance. Once the data at the water quality monitoring port exceeds the preset range, the PLC immediately triggers an alarm to notify the operator and takes corresponding emergency measures, such as suspending drainage or adding treatment steps. The specific operating procedure is as follows:

[0109] When the system starts up, the PLC controller reads the pressure difference between the current UF membrane 302 and the activated carbon filter layer 303, as well as various parameters of the water quality detection port 305, to confirm whether it is in a normal state.

[0110] The PLC reads data from each sensor at regular intervals, such as every minute, to monitor the operation of the post-processing unit in real time.

[0111] If the pressure difference of the UF membrane 302 is found to be too high or the pressure difference before and after the activated carbon filter layer 303 is found to be abnormally large, the PLC will immediately start the corresponding cleaning or regeneration program.

[0112] If the water quality monitoring port 305 shows that the water quality exceeds the standard, the PLC will automatically adjust the treatment strategy, such as increasing the treatment time or intensity, to ensure the quality of the effluent.

[0113] Set upper and lower limit alarm thresholds for water quality. Once these limits are exceeded, the PLC will trigger an alarm to notify the operator and execute predefined safety measures, such as suspending drainage or activating emergency response procedures.

[0114] The system records all water quality measurements and treatment actions, generating log files for subsequent analysis and auditing. It also regularly generates reports for administrators to help them understand the system's operational status.

[0115] Through the aforementioned mechanism, the post-treatment unit effectively removes residual small-molecule organic matter and trace heavy metal ions from dyeing and printing wastewater, ensuring the quality of the final effluent. This intelligent management system not only enhances the reliability and stability of the system but also improves the environmental performance and economic benefits of the entire advanced dyeing and printing wastewater treatment equipment. This post-treatment system demonstrates its superior performance, reacting rapidly under different water quality conditions, maintaining stable treatment results, preventing the risk of excessive chemical addition, and ensuring the safe operation of the equipment.

[0116] The integrated monitoring unit can efficiently realize the automated management and remote monitoring of the system, including:

[0117] PLC Controller: As the core control unit of the entire system, it is responsible for receiving data from various sensors and issuing control commands to actuators such as pumps and valves according to preset algorithms. The PLC possesses powerful data processing capabilities and real-time response characteristics, ensuring stable system operation. The PLC integrates multiple functional modules, including but not limited to:

[0118] Data acquisition module: Used to collect data from various sensors.

[0119] Data processing module: Analyzes and processes the collected data to provide a basis for decision-making.

[0120] Control output module: Generates control signals based on the analysis results to drive the corresponding actuators.

[0121] Storage module: Stores long-term historical data to support subsequent big data analysis and prediction.

[0122] The data acquisition module connects to sensors at all key locations, such as pH sensor 209, COD sensor 204, salinity sensor 211, pressure sensor 107, and ORP sensor 109. High-precision analog or digital input interfaces ensure the accuracy and stability of data transmission. Timestamp technology guarantees precise synchronization of data from different sources, facilitating subsequent data integration and analysis.

[0123] The communication interface is equipped with an Ethernet port or other high-speed network interface, supporting the TCP / IP protocol, allowing the system to access the enterprise intranet or the Internet for convenient remote access and management. Wireless communication options include optional Wi-Fi and 4G / 5G modules to ensure communication continuity in the absence of a wired network, making it particularly suitable for mobile monitoring or temporary deployment scenarios. Standard protocol support is provided, including industry-standard communication protocols such as Modbus RTU / TCP, Profibus, and Profinet, facilitating integration with other third-party systems. SSL / TLS encryption technology is used during communication to ensure the security and integrity of data transmission and prevent unauthorized access.

[0124] The local control panel features a touchscreen human-machine interface (HMI) in an easily accessible location, allowing field operators to view real-time data, adjust parameters, and intervene manually. It is configured with a web-based or mobile application, enabling administrators to monitor system status anytime, anywhere via computer or smartphone, receive alarm information, and respond promptly. An intuitive graphical interface displays key performance indicators (KPIs), trend charts, historical records, etc., helping users quickly understand the system's health status. Multiple alarm mechanisms, such as SMS, email, and app push notifications, are set up to immediately notify relevant personnel when anomalies are detected.

[0125] The PLC automatically adjusts the operating parameters of each treatment unit based on sensor feedback data, such as initiating backwashing procedures, regulating ozone supply, adjusting current intensity, and correcting pH values ​​to ensure optimal treatment results. Machine learning algorithms, such as LSTM, predict water quality trends and intelligently switch between energy-saving and high-efficiency treatment modes, ensuring both treatment efficiency and energy conservation. Historical data analysis provides early warnings of potential problems, such as recommending replacement of UF membranes or activated carbon filter layers, reducing unplanned downtime. Detailed contingency plans are developed for potential emergencies and implemented immediately upon triggering to ensure safe and reliable system operation.

[0126] The system automatically records all operation logs, alarm events, and handling actions, forming a complete activity trajectory to facilitate troubleshooting and accountability. It automatically generates detailed operational reports at set intervals, covering trends in key indicators, processing efficiency assessments, and other content to assist management in making informed decisions. It also supports auditing all changes within a specific time period to ensure compliance with regulatory requirements and improve the company's compliance management level.

[0127] Through the aforementioned mechanism, the integrated monitoring unit not only achieves fully automated management of the advanced treatment equipment for dyeing and printing wastewater, but also provides convenient and efficient remote monitoring methods. This intelligent management system enhances the system's reliability and stability, while significantly improving environmental performance and economic benefits. It demonstrates excellent adaptability and flexibility, capable of responding rapidly under different conditions, maintaining stable treatment results, and effectively reducing operating costs and maintenance complexity.

[0128] This application also provides a method for deep treatment of dyeing and printing wastewater, including the following steps:

[0129] S1. Pretreatment Stage: Wastewater passes through a pretreatment tower 100 and a multi-stage filtration system consisting of a screen 101, a sand filter 102, and a microfiltration membrane 103 to remove suspended particulate matter of different sizes. A pressure sensor 107 at the bottom of the sand filter 102 monitors the differential pressure in real time. When the pressure exceeds a set threshold (e.g., 0.5 bar), the PLC controller initiates a backwashing procedure to ensure continuous and stable filtration. After multi-stage filtration, the wastewater enters the oxidation tank. Ozone is decomposed into fine bubbles through a microporous aeration head 114, ensuring full contact with the wastewater and enhancing the oxidation reaction rate. An ORP sensor 109 monitors the oxidation-reduction potential in real time and automatically adjusts the ozone supply to maintain optimal oxidation conditions. Combined with UV light irradiation and the addition of a specific catalyst by a catalyst addition pump 110, the oxidation reaction rate is further increased. Exhaust gas undergoes specialized treatment through an exhaust gas collection port 111 to ensure a safe and environmentally friendly operating environment.

[0130] S2. Electrolysis Treatment Stage: The pretreated wastewater is pumped into the electrolysis cell 200 by pump 205. Current is applied between the anode 201 and cathode 202. A modified graphene-based composite material is used as the anode to enhance the efficiency of the electrochemical reaction. An online COD sensor 204 monitors water quality changes in real time and dynamically adjusts the current output parameters using a long short-term memory network algorithm to ensure optimal treatment results under different load conditions. According to actual needs, the sodium chloride content in the wastewater is adjusted by the salinity correction pump 203 to ensure suitable electrolysis conditions.

[0131] S3. pH adjustment stage: The pH value of the wastewater is monitored in real time using an online pH sensor 209. The pH correction pump 208 accurately adds an appropriate amount of acid or alkali solution according to the feedback data to maintain the pH value within the target range (e.g., 6.0 to 8.5).

[0132] S4. Post-treatment stage: Wastewater passes through UF membrane 302 and activated carbon filter layer 303 for further purification. Ultrasonic cleaner 304 operates periodically to prevent membrane surface fouling and clogging. Water quality testing port 305 is equipped with an online water quality analyzer to monitor effluent water quality indicators in real time, ensuring that the water meets discharge or reuse standards.

[0133] This application provides a highly efficient, intelligent, and environmentally friendly advanced treatment device and method for dyeing and printing wastewater, achieving effective removal and purification of various pollutants in the wastewater. Its main technical effects are as follows:

[0134] 1. Highly efficient multi-stage preprocessing

[0135] Removal of suspended solids and macromolecular organic matter: The multi-stage filtration system, consisting of a screen, sand filter, and microfiltration mesh, effectively removes suspended particles of different sizes, providing a stable water quality input for subsequent treatment.

[0136] Automatic backwashing mechanism: High-precision pressure sensors monitor differential pressure in real time, and the PLC controller automatically starts the backwashing program according to the set threshold to prevent filter media from clogging, ensure continuous and stable filtration effect, and reduce the need for manual maintenance.

[0137] 2. Enhanced advanced oxidation pretreatment

[0138] Ozone oxidation tower: It adopts countercurrent contact, turbulent contact and other methods to make ozone gas fully dissolve in wastewater and enhance the oxidation reaction rate; combined with UV light and specific catalysts (such as titanium dioxide TiO2), it further enhances the oxidation reaction rate and significantly reduces the concentration of organic pollutants.

[0139] Dynamic air intake adjustment: The ORP sensor monitors the oxidation-reduction potential in real time and automatically adjusts the ozone supply to maintain optimal oxidation conditions. At the same time, the exhaust gas collection port ensures the safety and environmental friendliness of the operating environment.

[0140] 3. Intelligent electrolysis treatment

[0141] Degrading organic pollutants and disinfecting: Modified graphene-based composite materials are used as anodes to enhance electrochemical reaction efficiency; combined with a long short-term memory network algorithm (LSTM) to implement an adaptive current control strategy, dynamically responding to water quality fluctuations and automatically optimizing current output parameters to ensure optimal treatment results under different load conditions.

[0142] Salinity control module: Built-in salinity sensor accurately measures sodium chloride content to ensure suitable electrolysis conditions and avoid the risk of byproduct formation; Safety protection module is set up, including over-excess warning mechanism and emergency response plan to ensure safe operation of equipment.

[0143] 4. Precise pH adjustment

[0144] Online pH monitoring and correction: A highly sensitive online pH sensor is used to monitor the pH changes in wastewater in real time. The pH correction pump accurately adds the appropriate amount of acid or alkali solution based on the feedback data to maintain the pH value within the target range (e.g., 6.0 to 8.5), ensuring the stability and effectiveness of the treatment process.

[0145] 5. Optimization of the post-processing unit

[0146] Removal of residual pollutants: The UF membrane and activated carbon filter layer effectively remove residual small molecule organic matter and trace heavy metal ions, ensuring that the final effluent quality meets the standards for discharge or reuse; the ultrasonic cleaner works regularly to prevent membrane surface fouling and clogging, extending the service life of the equipment.

[0147] Intelligent Management System: The PLC controller manages the post-processing unit in a unified manner, receives data from various sensors, automatically starts cleaning or regeneration programs, and issues regeneration or replacement prompts in advance to ensure the reliability and stability of the system.

[0148] 6. Integrated monitoring and remote management

[0149] Automated management and remote monitoring: The PLC controller, as the core control unit, is responsible for receiving data from various sensors and issuing control commands to the actuators according to preset algorithms; it supports remote access and management, allowing managers to monitor the system's operating status anytime, anywhere, receive alarm information, and respond promptly.

[0150] Data security and compliance: SSL / TLS encryption technology is used during communication to ensure the security and integrity of data transmission; the system automatically records all operation logs, alarm events and handling actions to form a complete activity track, which facilitates fault diagnosis and accountability, ensures compliance with regulatory requirements, and improves the company's compliance management level.

[0151] In summary, the advanced treatment equipment and method for dyeing and printing wastewater provided in this application demonstrate superior technical performance, rapidly responding to different water quality conditions and maintaining stable treatment results, while also meeting the requirements of energy conservation and environmental protection. This advanced treatment method not only enhances the intelligent management level of the system but also improves the reliability and environmental performance of the entire dyeing and printing wastewater treatment equipment, significantly reducing operating costs and maintenance difficulties, achieving a win-win situation for both economic and environmental benefits.

Claims

1. A deep treatment device for dyeing and printing wastewater, characterized in that, The system includes a pretreatment unit, an electrolysis unit, a pH adjustment unit, a post-treatment unit, and a comprehensive monitoring unit. The pretreatment unit comprises a physical filtration device and an advanced oxidation pretreatment device for removing suspended solids and large organic molecules. The electrolysis unit is equipped with a current control module and a salinity adjustment module for degrading organic pollutants and disinfecting. The pH adjustment unit is equipped with a pH sensor and a pH calibration pump for precisely controlling pH changes during the treatment process. The post-treatment unit includes an ultrafiltration membrane and activated carbon for removing residual small organic molecules and trace heavy metal ions. The integrated monitoring unit integrates a PLC controller, a data acquisition module, and a communication interface to realize automated management and remote monitoring of the system. The pretreatment unit includes a pretreatment tower (100), which includes a grid (101), a sand filter (102), and a microfiltration membrane (103) arranged from top to bottom. The upper part of the grid (101) is provided with a dyeing and printing wastewater inlet (105). The upper part of the sand filter (102) is provided with several flexible high-pressure flushing spray heads (106). The bottom of the sand filter (102) is provided with a pressure sensor (107). The lower part of the microfiltration membrane (103) is provided with a conical filter bucket (104). The conical opening of the conical filter bucket (104) is provided with... It has a spiral outlet (108), and a spiral baffle is provided inside the spiral outlet (108). The filtrate enters the bottom oxidation tank along the spiral baffle. The oxidation tank includes an ozone tube (113) at the bottom. Several microporous aeration heads (114) are provided on the ozone tube (113). A turbine mixer (112) is also provided in the upper part of the ozone tube (113) in the oxidation tank. A catalyst addition pump (110), an exhaust gas collection port (111), and an ORP sensor (109) are also provided in the upper part of the oxidation tank. An ultraviolet lamp is also integrated in the oxidation tank. The electrolysis unit includes an electrolysis cell (200), and the oxidation pool of the pretreatment tower (100) is connected to the electrolysis cell (200) via a pipeline. The electrolysis cell (200) is also equipped with several COD sensors (204) and salinity sensors (211). The COD sensor (204) is electrically connected to the PLC controller. The PLC controller uses its built-in data processing module to analyze the received COD signal and predict the required current density adjustment range based on the water quality change trend. Specifically, the prediction of the required current density adjustment range based on the water quality change trend is achieved through adaptive control using a long short-term memory network algorithm. The specific steps include: Collect and organize historical data, including COD concentration, temperature, and pH value, and normalize the data. The data is divided into training and test sets. 70% of the data is used as the training set and 30% of the data is used as the test set to construct time series samples. For each time point t, the data of the past n time points are used as input and the optimal current intensity at time t is used as the label. The LSTM model is trained using the training set, and the loss function is minimized through the backpropagation algorithm to adjust the hyperparameters. Evaluate the model's performance on the test set, calculate the error between the predicted and actual values, and adjust the model structure or parameters based on the evaluation results. The trained LSTM model is deployed to the PLC controller to receive data from the sensors in real time, predict and output the optimal current intensity; To achieve closed-loop control, the current output is dynamically adjusted based on the prediction results, while new data is continuously collected for online learning and model updates. The PLC controller dynamically adjusts the current output based on the received real-time COD data and the preset optimal current range. When the COD concentration is lower than the set threshold, the PLC will trigger the energy-saving mode to reduce the current intensity; otherwise, it will increase the current density. The post-processing unit includes a post-processing tank (300), and the bottom of the electrolysis tank (200) is connected to the post-processing tank (300) through a pipe and a post-processing water pump (301).

2. The advanced treatment equipment for dyeing and printing wastewater according to claim 1, characterized in that, The control valve and pressure sensor (107) of the flexible high-pressure flushing spray head (106) are electrically connected to the PLC controller. When the pressure value detected by the pressure sensor (107) under the sand filter (102) exceeds the preset threshold, the flexible high-pressure flushing spray head (106) is triggered by the PLC controller to flush the sand filter (102). The flow control valve of the ORP sensor (109) and the ozone tube (113) are electrically connected to the PLC controller. The PLC controller has a preset ORP range. When the ORP sensor (109) detects that the ORP value deviates from the set range, the flow control valve of the ozone tube (113) is adjusted by the PLC controller.

3. The advanced treatment equipment for dyeing and printing wastewater according to claim 1, characterized in that, A water pump (205) and a control valve (206) are installed on the pipe connecting the pretreatment tower (100) and the electrolytic cell (200). The upper part of the electrolytic cell (200) is provided with a wastewater inlet (207) to be electrolyzed. The pipe is connected to the wastewater inlet (207) of the electrolytic cell (200). The electrolytic cell (200) includes an anode electrode (201) and a cathode electrode (202). A salinity correction pump (203) is connected to one side of the electrolytic cell (200) and is equipped with a corresponding solenoid valve.

4. The advanced treatment equipment for dyeing and printing wastewater according to claim 3, characterized in that, The solenoid valves corresponding to the salinity sensor (211) and the salinity correction pump (203) are electrically connected to the PLC controller. The PLC controller reads the data of the salinity sensor (211) at regular intervals. If the salinity is found to be lower or higher than the ideal range, the PLC controller immediately starts the correction program and adds an appropriate amount of sodium chloride solution through the salinity correction pump (203) to bring the salinity back to the set range.

5. The advanced treatment equipment for dyeing and printing wastewater according to claim 2, characterized in that, The pH adjustment unit includes a pH correction pump (208) installed on one side of the electrolytic cell (200). The pH correction pump (208) is equipped with a corresponding solenoid valve. The electrolytic cell (200) is also equipped with several pH sensors (209) and several first ultrasonic cleaners (210). The solenoid valve and pH sensor (209) corresponding to the pH correction pump (208) are electrically connected to the PLC controller. The PLC controller calculates the amount of acid or alkali to be added based on the data fed back by the pH sensor (209) and outputs control commands to the pH correction pump (208).

6. The advanced treatment equipment for dyeing and printing wastewater according to claim 2, characterized in that, The post-treatment tank (300) is equipped with a vertical UF membrane (302) and an activated carbon filter layer (303). A second ultrasonic cleaner (304) is provided at the front end of the UF membrane (302). The post-treatment tank (300) is provided with a water quality detection port (305) and a drain outlet (306) on the side corresponding to the activated carbon filter layer (303).

7. A method for treating dyeing and printing wastewater using the advanced treatment equipment for dyeing and printing wastewater as described in any one of claims 1-6, characterized in that, Including the following steps: S1. Pretreatment stage: The dyeing and printing wastewater passes through the pretreatment tower (100), and is filtered by the screen (101), sand filter (102), and micro-filter cotton (103) to remove suspended particulate matter; After being filtered through multiple stages, the wastewater enters the oxidation tank for oxidation reaction. The oxidation-reduction potential is monitored in real time using an ORP sensor (109), and the ozone supply is automatically adjusted. S2. Electrolysis treatment stage: The pretreated wastewater is pumped into the electrolysis cell (200) by a water pump (205). Current is applied between the anode electrode (201) and the cathode electrode (202). The COD sensor (204) monitors the water quality changes in real time. The current output parameters are dynamically adjusted by combining the long short-term memory network algorithm. The sodium chloride content in the wastewater is adjusted by the salinity correction pump (203) to ensure suitable electrolysis conditions. S3. pH adjustment stage: The pH value change in the wastewater is monitored in real time using an online pH sensor (209), and the pH correction pump (208) accurately adds an appropriate amount of acid or alkali solution according to the feedback data to keep the pH value within the target range; S4. Post-treatment stage: Wastewater is purified by passing through a UF membrane (302) and an activated carbon filter layer (303). The water quality detection port (305) is equipped with an online water quality analyzer to monitor the water quality indicators in real time and ensure that the water meets the standards for discharge or reuse.

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