Efficient coagulant for esterification wastewater treatment, control system and adding method

Abstract

The invention provides an efficient coagulant for esterification wastewater treatment, a control system and an adding method, and the efficient coagulant comprises a composite coagulant solution which is prepared from an iron-based or aluminum-based inorganic polymer coagulant, a polymer flocculant and an electrochemical activation enhancer; the electrochemical activation module is used for carrying out online activation on the composite coagulant solution and comprises at least one group of cathode and anode, and the anode adopts a metal oxide coating titanium electrode with catalytic activity; and the intelligent control system is used for monitoring water quality parameters of the esterification wastewater in real time and dynamically adjusting the current density and / or voltage of the electrochemical activation module and the feeding rate of the composite coagulant solution based on the water quality parameters.

Description

Technical Field

[0001] This invention relates to the field of intelligent control systems for environmental wastewater treatment, and more specifically, to a high-efficiency coagulant, control system, and dosing method for treating esterification wastewater. Background Technology

[0002] Currently, wastewater generated from esterification reactions (such as the production of polyesters, ester solvents, fragrances, etc.) typically has the following characteristics: high organic matter content (COD): containing alcohols, acids, unreacted esters, etc., with a high COD / BOD ratio, making it difficult to degrade; high salinity: acids / alkalis are often used as catalysts or neutralizing agents during the production process, resulting in high salinity; large pH fluctuations: the properties of the wastewater are affected by production batches, with a large range of pH values; deep color and fine suspended solids: difficult to remove through simple sedimentation or filtration; existing esterification wastewater treatment methods mainly include biochemical methods, advanced oxidation methods, and physicochemical methods (such as coagulation sedimentation); among them, coagulation is often used as a pretreatment method due to its low cost and simple operation; The existing physicochemical coagulation methods mainly have the following drawbacks: 1. Low coagulation efficiency: Traditional inorganic coagulants (such as polyaluminum chloride PAC, ferrous sulfate, etc.) require large dosages when treating high organic matter and high salinity esterification wastewater, but have low removal rates for fine colloidal particles and some recalcitrant organic matter. 2. High sludge production: The large amount of coagulant added directly leads to a high production of chemical sludge, which increases the cost of subsequent sludge treatment; 3. Sensitive to pH: Traditional coagulants have a narrow optimal pH range, requiring large amounts of acid and alkali to adjust, increasing operational complexity and reagent costs; Inorganic coagulants have insufficient activity: The formation rate and activity of effective metal hydrolysis products (such as polynuclear hydroxyl complexes) in coagulants are limited, restricting their treatment effect on high-concentration wastewater; These problems remain to be solved; Therefore, it is necessary to propose a high-efficiency coagulant, control system, and dosing method for esterification wastewater treatment to at least partially solve the problems existing in the prior art. Summary of the Invention

[0003] The summary of this invention introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary of this invention does not mean that it attempts to limit the key features and essential technical features of the claimed technical solution, nor does it mean that it attempts to determine the scope of protection of the claimed technical solution.

[0004] To at least partially solve the above problems, the present invention provides a high-efficiency coagulant and control system for esterification wastewater treatment, comprising: The composite coagulant solution is formulated from iron-based or aluminum-based inorganic polymer coagulants, polymeric flocculants, and electrochemical activators and enhancers. An electrochemical activation module for online activation of the composite coagulant solution includes at least one set of cathodes and anodes, wherein the anode is a titanium electrode coated with a metal oxide that has catalytic activity. The intelligent control system is used to monitor the water quality parameters of esterification wastewater in real time, and dynamically adjust the current density and / or voltage of the electrochemical activation module, as well as the dosing rate of the composite coagulant solution based on the water quality parameters. The composite coagulant solution is formulated from iron-based or aluminum-based inorganic polymer coagulants, polymeric flocculants, and electrochemical activators and enhancers. Iron-based or aluminum-based inorganic polymeric coagulants are high-efficiency composite coagulants, including: Main agent: An iron-based or aluminum-based inorganic polymeric coagulant (such as PAC or polyferric sulfate PFS); Auxiliary agent: A polymeric flocculant (such as polyacrylamide PAM) and an electrochemical activating enhancer (such as sodium chloride (NaCl) or sodium sulfate in a specific ratio). isoelectrolytes; Device structure: The activation module adopts a parallel plate electrode or three-dimensional electrode structure, and the electrode material is selected from materials with high catalytic activity (such as doped metal oxide coated titanium plates). Control system: A microprocessor control system (MCU) is adopted to dynamically adjust the current density, voltage and activation time of the electrochemical activation module by real-time monitoring parameters such as turbidity, conductivity and / or oxidation-reduction potential (ORP) of esterification wastewater, so as to achieve real-time control of coagulant activity.

[0005] Preferably, the electrochemical activating agent is sodium chloride (NaCl) or sodium sulfate. Its function is to provide electrolytes and / or enhance the generation of active free radicals.

[0006] Preferably, the anode coating material of the electrochemical activation module is selected from iridium-tantalum oxide. or ruthenium-iridium oxide .

[0007] Preferably, the intelligent control system includes: Water quality sensor: used to collect turbidity and oxidation-reduction potential (ORP) signals of esterification wastewater; Microprocessor (MCU): Used to receive the signal and execute a control algorithm that combines feedforward and feedback.

[0008] Preferably, the feedforward control algorithm is based on an artificial neural network (ANN) or a nonlinear regression model to predict the optimal activation current density (Jopt) and the optimal coagulant dosing rate (Qopt) in real time.

[0009] Preferably, the electrochemical activation module adopts a DC constant current mode or a pulse current mode, and its current density control range is 5mA / cm2 to 30mA / cm2.

[0010] This invention discloses a high-efficiency coagulant for treating esterification wastewater and a method for controlling its addition, comprising the following steps: Step 1: Monitor key water quality parameters (turbidity, ORP) of esterification wastewater in real time. Step 2: The composite coagulant solution is delivered to the electrochemical activation module for online activation; Step 3: Based on the water quality parameters monitored in Step 1, the intelligent control system calculates and dynamically adjusts the current density of the activation module in real time. Step 4: The activated composite coagulant solution is added to the esterification wastewater at a dynamically adjusted rate for coagulation treatment. The electrochemical activation module performs online activation, including: Before or during the addition of the composite coagulant to the esterification wastewater, the coagulant solution is activated by an electrochemical activation module. Activation principle: A direct current electric field (or pulsed electric field) is applied to the solution of the activator and coagulant, causing highly active flocculants, such as active hydroxyl radicals, to be generated in situ near the cathode and anode. High-valence metal ions (such as nascent hydroxide flocs generated through electrolysis).

[0011] The process of adding the activated composite coagulant solution to the esterification wastewater at a dynamically adjusted rate for coagulation treatment includes: real-time monitoring based on the above-mentioned electrochemical activation and control using an intelligent dosing method; real-time acquisition of wastewater quality parameters (turbidity, estimated COD, pH); model prediction: establishing a nonlinear regression model of coagulant demand and electrochemical activation degree based on historical data and activation parameters; and dynamic adjustment: simultaneously adjusting the dosing rate of the electrochemically activated composite coagulant (via a metering pump) and the current / voltage of the electrochemical activation module according to the model calculation results.

[0012] Preferably, when the pH value of the wastewater exceeds the optimal coagulation range (less than 5.0 or greater than 8.0), the control system increases the activation current density to generate more active flocculants in order to maintain the coagulation effect.

[0013] Preferably, the dynamic adjustment of current density in step 3 includes minimizing the energy consumption per unit volume of treated water (kWh / m3) while ensuring coagulation removal efficiency.

[0014] Preferably, the volume ratio of iron-based or aluminum-based inorganic polymeric coagulant to polymeric flocculant in the composite coagulant is between 99:1 and 95:5, and the electrochemical activation time is controlled between 10s and 60s.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects: This invention provides a high-efficiency coagulant, control system, and dosing method for treating esterification wastewater. It involves real-time monitoring of key water quality parameters (turbidity, ORP) of the esterification wastewater; delivering a composite coagulant solution to an electrochemical activation module for online activation; calculating and dynamically adjusting the current density of the activation module in real time based on the monitored water quality parameters; and adding the activated composite coagulant solution to the esterification wastewater at a dynamically adjusted rate for coagulation treatment. The online activation of the electrochemical activation module includes: activating the coagulant solution before or simultaneously with the addition of the composite coagulant to the esterification wastewater using an electrochemical activation module; and applying a DC electric field (or pulsed electric field) to the activation enhancer and coagulant solution to generate highly active flocculants, such as active hydroxyl radicals, in situ near the cathode and anode. High-valence metal ions (such as nascent hydroxide flocs generated through electrolysis); the activated composite coagulant solution is added to esterification wastewater at a dynamically adjusted rate for coagulation treatment, including: intelligent dosing method, based on the above electrochemical activation and control, real-time monitoring: real-time collection of wastewater quality parameters (turbidity, COD estimate, pH); model prediction: based on historical data and activation parameters, a nonlinear regression model of coagulant demand and electrochemical activation degree is established; dynamic adjustment: according to the model calculation results, the dosing rate of the electrochemically activated composite coagulant (via metering pump) and the current / voltage of the electrochemical activation module are adjusted simultaneously; 1. Highly efficient removal: Increases the overall removal rate of COD, color, and suspended solids in esterification wastewater by more than 15%; 2. Chemical savings: The amount of coagulant added can be reduced by more than 20%, significantly reducing operating costs; 3. High adaptability: The activated coagulant can maintain high activity in the pH range of 4.0 to 9.0, reducing or eliminating the pH adjustment step; 4. Sludge reduction: Reducing the amount of coagulant added results in a decrease in sludge production. 5. Intelligent control: Through real-time adjustment of current and voltage parameters, the coagulant activity is accurately generated on demand, significantly improving the system's stability and response speed; this has significant meaning and remarkable effects.

[0016] The present invention provides a high-efficiency coagulant, control system, and dosing method for treating esterification wastewater. Other advantages, objectives, and features of the present invention will be partly apparent from the following description and partly understood by those skilled in the art through study and practice of the invention. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a diagram of an embodiment of the high-efficiency coagulant and control system for esterification wastewater treatment according to the present invention.

[0018] Figure 2 This is a diagram of an embodiment of the high-efficiency coagulant and controlled dosing method for treating esterification wastewater according to the present invention. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, so that those skilled in the art can implement it based on the specification; as shown in the figures, the present invention provides a high-efficiency coagulant and control system for esterification wastewater treatment, including: Composite coagulant solution 01 is formulated from iron-based or aluminum-based inorganic polymer coagulant, polymer flocculant and electrochemical activator enhancer; Electrochemical activation module 02 is used to activate the composite coagulant solution online, and includes at least one set of cathodes and anodes, wherein the anode is a titanium electrode coated with a metal oxide that has catalytic activity; The intelligent control system 03 is used to monitor the water quality parameters of esterification wastewater in real time, and dynamically adjust the current density and / or voltage of the electrochemical activation module, as well as the dosing rate of the composite coagulant solution based on the water quality parameters. The composite coagulant solution is formulated from iron-based or aluminum-based inorganic polymer coagulants, polymeric flocculants, and electrochemical activators and enhancers. Iron-based or aluminum-based inorganic polymeric coagulants are high-efficiency composite coagulants, including: Main agent: An iron-based or aluminum-based inorganic polymeric coagulant (such as PAC or polyferric sulfate PFS); Auxiliary agent: A polymeric flocculant (such as polyacrylamide PAM) and an electrochemical activating enhancer (such as sodium chloride (NaCl) or sodium sulfate in a specific ratio). isoelectrolytes; Device structure: The activation module adopts a parallel plate electrode or three-dimensional electrode structure, and the electrode material is selected from materials with high catalytic activity (such as doped metal oxide coated titanium plates). Control system: A microprocessor control system (MCU) is adopted to dynamically adjust the current density, voltage and activation time of the electrochemical activation module by real-time monitoring parameters such as turbidity, conductivity and / or oxidation-reduction potential (ORP) of esterification wastewater, so as to achieve real-time control of coagulant activity. The compound coagulant formulation includes: Main component: Polyferric sulfate (PFS), Fe3+ content ≥19.0%; Additive 1 (flocculator): Anionic polyacrylamide (APAM), degree of hydrolysis ; Additive 2 (activator / electrolyte): NaCl, mass concentration ; Composite agent ratio: PFS solution and APAM solution are mixed at a ratio of 99:1 to 95:5 (volume ratio), and then NaCl is added as an activating enhancer; Electrochemical activation module structure: adopts a tubular reactor 021, with multiple sets of plate electrodes 022 inside; electrode material: the anode is an iridium-tantalum oxide coated titanium electrode. The cathode is made of stainless steel or titanium. Electrode spacing... Operating modes: DC constant current mode or pulsed current mode; pulsed mode further improves the efficiency of free radical generation and reduces electrode passivation; Activation zone: the activation module is designed in online mode, and the coagulant solution flows through this module before addition, with activation time... ; The intelligent control system includes: Water quality sensor 031: A turbidity meter, an ORP sensor, and a pH sensor are installed at the inlet of the esterification wastewater to transmit the signals to the MCU in real time; Main Controller (MCU) 032: Employs a high-performance microcontroller (such as an ARM core) to execute control algorithms; High-frequency power supply module 033: Used in electrochemical activation modules, providing adjustable voltage and adjustable current density; Metering pump 034: Used to control the dosage of activated coagulant, and has the following functions: Flow control interface for signal input.

[0020] In one embodiment, the electrochemical activating enhancer is sodium chloride (NaCl) or sodium sulfate. Its function is to provide electrolytes and / or enhance the generation of active free radicals.

[0021] In one embodiment, the anode coating material of the electrochemical activation module is selected from iridium-tantalum oxide. or ruthenium-iridium oxide .

[0022] In one embodiment, the intelligent control system includes: Water quality sensor: used to collect turbidity and oxidation-reduction potential (ORP) signals of esterification wastewater; Microprocessor (MCU): Used to receive the signal and execute a control algorithm that combines feedforward and feedback.

[0023] In one embodiment, the feedforward control algorithm is based on an artificial neural network (ANN) or a nonlinear regression model to predict the optimal activation current density (Jopt) and the optimal coagulant dosing rate (Qopt) in real time.

[0024] In one embodiment, the electrochemical activation module employs a DC constant current mode or a pulsed current mode, with a current density control range of 5 mA / cm² to 30 mA / cm².

[0025] In one embodiment, based on energy-saving activation using pulsed current mode, the composite coagulant solution is activated using pulsed current mode. Activation mode: The intelligent control system (MCU) controls the high-frequency power module to output pulse current instead of constant DC current.

[0026] Control parameters: The intelligent control system (MCU) predicts the optimal activation intensity based on the influent ORP signal (reflecting organic load), and then adjusts the duty cycle and frequency of the pulse current instead of directly adjusting the average current density. Electrode maintenance: When not performing activation (during pulse trough), switching to polarity reversal mode (or extremely low reverse current) can remove the passivation layer on the electrode surface and extend the anode life. Service life; Activation target: Activation time of 20s to ensure maximum efficiency in oxidizing Fe3+ to highly active FeIV / FeVI or generating OH; Significant energy saving effect: Compared with DC constant current mode, pulse current mode can reduce average energy consumption by more than 10% to achieve the same flocculation activity effect, resulting in a significant reduction in power consumption per unit volume of treated water.

[0027] Increased free radical yield: Pulsed mode facilitates the instantaneous high concentration generation of active free radicals (such as OH), improving the pre-oxidation effect on organic matter aggregation.

[0028] This invention discloses a high-efficiency coagulant for treating esterification wastewater and a method for controlling its addition, comprising the following steps: Step 1: Monitor key water quality parameters (turbidity, ORP) of esterification wastewater in real time. Step 2: The composite coagulant solution is delivered to the electrochemical activation module for online activation; Step 3: Based on the water quality parameters monitored in Step 1, the intelligent control system calculates and dynamically adjusts the current density of the activation module in real time. Step 4: The activated composite coagulant solution is added to the esterification wastewater at a dynamically adjusted rate for coagulation treatment. The electrochemical activation module performs online activation, including: Before or during the addition of the composite coagulant to the esterification wastewater, the coagulant solution is activated by an electrochemical activation module. Activation principle: A direct current electric field (or pulsed electric field) is applied to the solution of the activator and coagulant, causing highly active flocculants, such as active hydroxyl radicals, to be generated in situ near the cathode and anode. High-valence metal ions (such as nascent hydroxide flocs generated through electrolysis).

[0029] The process of adding the activated composite coagulant solution to the esterification wastewater at a dynamically adjusted rate for coagulation treatment includes: real-time monitoring based on the above-mentioned electrochemical activation and control using an intelligent dosing method; real-time acquisition of wastewater quality parameters (turbidity, estimated COD, pH); model prediction: establishing a nonlinear regression model of coagulant demand and electrochemical activation degree based on historical data and activation parameters; and dynamic adjustment: simultaneously adjusting the dosing rate of the electrochemically activated composite coagulant (via a metering pump) and the current / voltage of the electrochemical activation module according to the model calculation results.

[0030] In one embodiment, when the pH of the wastewater exceeds the optimal coagulation range (less than 5.0 or greater than 8.0), the control system increases the activation current density to generate more active flocculants in order to maintain the coagulation effect.

[0031] In one embodiment, the dynamic adjustment of current density in step 3 includes minimizing the power consumption per unit volume of treated water (kWh / m3) while ensuring coagulation removal efficiency.

[0032] In one embodiment, the volume ratio of iron-based or aluminum-based inorganic polymeric coagulant to polymeric flocculant in the composite coagulant is between 99:1 and 95:5, and the electrochemical activation time is controlled between 10s and 60s. The control algorithm includes: Feedback control: PID (proportional-integral-derivative) feedback control algorithm based on influent turbidity / ORP and effluent turbidity; Feedforward control: Based on influent turbidity, ORP, and pH, the optimal current density is predicted using a pre-established nonlinear model (such as a model based on an artificial neural network (ANN)). and optimal coagulant dosing rate ; Current density Affecting activating substances The generation rate; Energy consumption

[0033] ; in Slot voltage, For current, For activation time, The volume of wastewater to be treated; the control objective is to minimize. While ensuring removal efficiency; Dynamic adjustment logic: When the turbidity or ORP (reflecting the concentration of organic matter) of the influent increases sharply, the MCU simultaneously increases the current density of the power module (to increase the activity of the coagulant) and the dosing rate of the metering pump; when the pH value of the wastewater exceeds the optimal coagulation range, the MCU enhances the activation current / voltage to compensate for the negative impact of pH on the coagulation effect with higher activation activity, thereby avoiding the addition of acid and alkali.

[0034] One embodiment involves current-compensated activation of high-pH wastewater: This addresses the treatment of high-pH wastewater (e.g., pH > 8.0) that may occur during the alkaline washing stage of esterification wastewater. When sensor 24 detects that the wastewater pH exceeds 8.0, it triggers the pH compensation logic of the MCU. The MCU adds an additional compensation current density (ΔJpH) based on the original dosing rate and Jopt. The increased current density (ΔJpH) generates a higher concentration of H+ ions and high-valence Fe flocculant in the solution, which neutralizes some of the... Ions, and maintain the effective hydrolytic form of Fe3+ / Al3+ flocculant under high pH conditions; Technical effect: Eliminates the need for pH adjustment: The activated coagulant in It maintains high activity within the specified range26. Through electrochemical activation compensation, the step of adding acid before high pH wastewater is significantly reduced or completely avoided27, reducing operational complexity and reagent costs; maintaining coagulation effect: even in non-optimal pH ranges, the generation of highly active flocculants still ensures stable COD and turbidity removal rates.

[0035] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. Other modifications can be easily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A high-efficiency coagulant and control system for treating esterification wastewater, characterized in that, include: The composite coagulant solution is formulated from iron-based or aluminum-based inorganic polymer coagulants, polymeric flocculants, and electrochemical activators and enhancers. An electrochemical activation module for online activation of the composite coagulant solution includes at least one set of cathodes and anodes, wherein the anode is a titanium electrode coated with a metal oxide that has catalytic activity. The intelligent control system is used to monitor the water quality parameters of esterification wastewater in real time, and dynamically adjust the current density and / or voltage of the electrochemical activation module, as well as the dosing rate of the composite coagulant solution based on the water quality parameters.

2. The high-efficiency coagulant and control system for esterification wastewater treatment according to claim 1, characterized in that, The electrochemical activator is sodium chloride (NaCl) or sodium sulfate. Its function is to provide electrolytes and / or enhance the generation of active free radicals.

3. The high-efficiency coagulant and control system for esterification wastewater treatment according to claim 1, characterized in that, The anode coating material of the electrochemical activation module is selected from iridium-tantalum oxide. or ruthenium-iridium oxide .

4. The high-efficiency coagulant and control system for esterification wastewater treatment according to claim 1, characterized in that, The intelligent control system includes: Water quality sensor: used to collect turbidity and oxidation-reduction potential (ORP) signals of esterification wastewater; Microprocessor (MCU): Used to receive the signal and execute a control algorithm that combines feedforward and feedback.

5. The high-efficiency coagulant and control system for esterification wastewater treatment according to claim 1, characterized in that, The feedforward control algorithm is based on an artificial neural network (ANN) or a nonlinear regression model to predict the optimal activation current density (Jopt) and the optimal coagulant dosing rate (Qopt) in real time.

6. The dosing system according to claim 1, characterized in that, The electrochemical activation module adopts a DC constant current mode or a pulse current mode, and its current density control range is 5mA / cm2 to 30mA / cm2.

7. A high-efficiency coagulant for treating esterification wastewater and a method for controlling its dosage, characterized in that, Includes the following steps: Step 1: Real-time monitoring of key water quality parameters of esterification wastewater; Step 2: The composite coagulant solution is delivered to the electrochemical activation module for online activation; Step 3: Based on the water quality parameters monitored in Step 1, the intelligent control system calculates and dynamically adjusts the current density of the activation module in real time. Step 4: The activated composite coagulant solution is added to the esterification wastewater at a dynamically adjusted rate for coagulation treatment.

8. The high-efficiency coagulant for esterification wastewater treatment and its controlled dosing method according to claim 6, characterized in that, When the pH value of the wastewater exceeds the optimal coagulation range (less than 5.0 or greater than 8.0), the control system increases the activation current density to generate more active flocculants in order to maintain the coagulation effect.

9. The high-efficiency coagulant for esterification wastewater treatment and its controlled dosing method according to claim 6, characterized in that, Step 3 involves dynamically adjusting the current density to minimize the energy consumption per unit volume of treated water (kWh / m3) while ensuring coagulation removal efficiency.

10. The high-efficiency coagulant for esterification wastewater treatment and its controlled dosing method according to claim 6, characterized in that, The volume ratio of iron-based or aluminum-based inorganic polymeric coagulant to polymeric flocculant in the composite coagulant is between 99:1 and 95:5, and the electrochemical activation time is controlled between 10s and 60s.

Images