Semiconductor industry sewage treatment and regeneration system and method thereof

Abstract

The invention discloses a semiconductor industry sewage treatment and regeneration system and a method thereof. The system comprises a quality-divided pretreatment device, a three-dimensional electric flocculation reactor, an intelligent membrane separation unit and an EDI deep purification device, the method comprises the following steps of dynamic quality separation, electrochemical strengthening and intelligent maintenance. According to the invention, the water purification efficiency is improved, the fluorine ion removal rate is greatly improved compared with the traditional removal rate, the total nitrogen removal rate is improved by 40%, the water production resistivity of ultrapure water is greater than or equal to 18M omega.cm and reaches the SEMIF63 standard, and the system is stable in operation; according to the method, the operation cost is reduced, the chemical consumption is greatly reduced through AI dynamic regulation and control, the water resource recycling effect is greatly improved, and the heavy metal recovery rate is greatly increased; the method accords with green production indexes, the sludge yield is reduced, and the risk of secondary pollution is reduced through the ozone catalysis technology.

Description

Technical Field

[0001] The present invention relates to the technical field of industrial wastewater treatment, and specifically to a system and method for the coordinated treatment and regeneration of multiple types of wastewater such as fluorine-containing wastewater, organic wastewater, and grinding wastewater generated in the semiconductor manufacturing process, which can achieve a water reuse rate of more than 90%. Background Art

[0002] Semiconductor manufacturing includes highly precise and complex silicon wafer cleaning, photolithography, etching and chemical mechanical polishing (CMP) and other multi-stage processes. A large amount of fluorine, phosphorus, ammonia, organic, acid, alkali and heavy metal wastewater is generated by rinsing and cleaning the semiconductor surface. The more advanced the semiconductor process, the higher the requirement for surface cleanliness, and the greater the water consumption and wastewater discharge.

[0003] There are still some shortcomings in the existing semiconductor wastewater treatment systems and methods:

[0004] 1. Insufficient quality-based treatment: Traditional processes mostly adopt a unified treatment mode, which does not effectively distinguish the characteristics of fluorine-containing, organic, and grinding wastewater, resulting in low treatment efficiency. For example, a wastewater treatment system based on a semiconductor membrane and its control method disclosed in a Chinese invention patent (Announcement No.: CN109626620A), the semiconductor membrane treatment system is only for emulsion wastewater; 2. Short electrode life: Conventional electrocoagulation devices have the problem of cathode scaling, and electrodes need to be replaced frequently. For example, a wastewater treatment method and device based on hydraulic cavitation disclosed in a Chinese invention patent (Announcement No.: CN105439322B), the hydraulic cavitation device runs for 3 hours. The efficiency drops by 40% after one month; 3. Severe membrane pollution: The flux attenuation of MBR membrane bioreactor is greater than 50% under the condition of SS>3000mg / L, such as the RO membrane separation process parameters in a semiconductor wastewater treatment method and system disclosed in a Chinese invention patent (Announcement No.: CN116282699B); 4. Lack of intelligence: It is difficult for existing control systems to dynamically adjust the coupling parameters of current density and ozone dosage, such as a semiconductor membrane-based wastewater treatment system and its control method disclosed in a Chinese invention patent (Announcement No.: CN109626620A), which only adjusts the centrifuge speed through a fixed formula. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art and to propose a semiconductor industry wastewater treatment and regeneration system and method.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A semiconductor industry wastewater treatment and regeneration system, comprising the following connected in sequence: a quality pretreatment device, equipped with a pH / ORP online monitoring and sorting module and an automatic dosing unit; a three-dimensional electro-flocculation reactor, comprising a honeycomb titanium-based nano-coated electrode plate and an ultrasonic descaling module; an intelligent membrane separation unit, composed of an acid- and alkali-resistant ceramic membrane component and an anti-pollution RO membrane component connected in series, and an automatic cleaning system with integrated multi-parameter feedback; an EDI deep purification device, whose outlet is connected to an ultrapure water storage tank; wherein the system also includes an AI control module based on an LSTM neural network, which regulates the operating parameters of each unit in real time.

[0008] Preferably, the active coating of the titanium-based nano-coated electrode plate is composited with RuO2 and IrO2 in a molar ratio of 3:1. The effective surface area of ​​the electrode plate is increased by 220% compared with that of the traditional flat electrode, and a 40kHz ultrasonic descaling module is built in to extend the electrode life to more than 12 months.

[0009] Preferably, the quality separation pretreatment device includes: a fluorine-containing wastewater diversion channel equipped with a Ca(OH)2 automatic dosing mechanism; an organic wastewater diversion channel, an ozone pre-oxidation contact tank; a grinding wastewater diversion channel, a micro-nano bubble flotation separator, which is equipped with a multi-spectral sensor array for detecting pH / ORP / turbidity, to achieve automatic classification of fluorine-containing wastewater, organic wastewater, and grinding wastewater.

[0010] Contains three-channel shunt structure:

[0011] Fluoride channel: Ca(OH)2 automatic dosing and vortex mixing reaction chamber.

[0012] Organic channel: ozone pre-oxidation contact tank.

[0013] Grinding channel: micro-nano bubble flotation separator.

[0014] Preferably, the automatic cleaning system of the intelligent membrane separation unit includes: a transmembrane pressure difference sensor with a detection accuracy of ±0.01MPa; a backwash module with a working pressure of 0.2-0.5MPa; a chemical cleaning liquid circulation unit equipped with a pH adaptive adjustment device, wherein the acid- and alkali-resistant ceramic membrane on the transmembrane pressure difference sensor has a pore size of 50nm and is connected in series with an anti-pollution RO membrane, and the transmembrane pressure difference control threshold is 0.8-1.2MPa.

[0015] Preferably, the ion exchange membrane stack of the EDI deep purification device adopts a bipolar membrane structure, the resistivity of the produced water is ≥18MΩ·cm, the polar water circulation flow rate is 10% to 15% of the produced water volume, the resistivity of the produced water is ≥18MΩ·cm, and the SEMIF63 ultrapure water standard is met.

[0016] A semiconductor industry wastewater treatment and regeneration method using the semiconductor industry wastewater treatment and regeneration system comprises the following steps: S1. Classifying wastewater into fluoride-containing wastewater, organic wastewater and grinding wastewater through an online monitoring and sorting module; S2. Adding Ca(OH)2 to the fluoride-containing wastewater until the pH is 6.5-7.0 to form CaF2 precipitation; S3. Controlling the current density in the three-dimensional electrocoagulation treatment stage to 15-50A / m 2 , and inject ozone 10-200 mg / L at the same time; S4. The intelligent membrane system switches the cleaning mode according to the feedback from the turbidity sensor; S5. The EDI device produces ultrapure water that is reused in the wafer cleaning process.

[0017] Preferably, the operating temperature of the ozone catalytic oxidation reactor in step S3 is 35-45° C., and the hydraulic retention time is 20-40 min.

[0018] Preferably, the transmembrane pressure difference control threshold of the intelligent membrane separation unit is 0.8-1.2 MPa, and the backwashing frequency is once every 30-60 minutes.

[0019] Preferably, the polar water circulation flow rate of the EDI deep purification device is 10% to 15% of the produced water flow rate, and the polar chamber pressure difference is maintained at 0.05 to 0.1 MPa.

[0020] Preferably, the AI ​​control module collects fluoride ion concentration, COD value and transmembrane pressure difference data in real time, dynamically optimizes the coupling parameters of current density and ozone dosage, and reduces the agent consumption by 20% to 30%.

[0021] AI dynamic control includes the following steps:

[0022] 1. Dynamic quality classification

[0023] Based on the LSTM neural network prediction model, the diversion ratio is adjusted in real time:

[0024] Among them, Qi is the flow rate of each channel, Ci is the characteristic concentration of pollutants, Q total is the sum of the flow rates of each channel.

[0025] 2. Electrochemical strengthening

[0026] At current density of 15 to 50 A / m 2 Within the range, the ozone dosage is dynamically adjusted to 10-200 mg / L according to the COD removal rate, and the following correlation is established:

[0027] O3=0.8×e 0.05I ×ΔCOD, where I is the current density and ΔCOD is the real-time COD change.

[0028] 3. Intelligent maintenance

[0029] When the transmembrane pressure difference is greater than 1.2 MPa, the gradient cleaning program is started:

[0030] Backwash stage: 0.35MPa pressure maintained for 3 minutes.

[0031] Chemical cleaning stage: NaOH solution with pH = 11.5 circulates for 30 minutes.

[0032] The present invention has the following beneficial effects:

[0033] 1. The water purification efficiency of the present invention is improved, the fluoride ion removal rate is greatly improved compared with the traditional removal rate, the total nitrogen removal rate is increased by 40%, the resistivity of ultrapure water production is ≥18MΩ·cm, reaching the SEMIF63 standard, and the system operation is stable.

[0034] 2. The present invention reduces operating costs, AI dynamic regulation greatly reduces the consumption of chemicals, greatly improves the recycling effect of water resources, and greatly improves the recovery rate of heavy metals.

[0035] 3. The present invention complies with green production indicators, reduces sludge production, and uses ozone catalysis technology to reduce the risk of secondary pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Flow chart of wastewater treatment and regeneration system for the semiconductor industry;

[0037] Figure 2 Block diagram of in-stream control system for wastewater treatment and regeneration system in semiconductor industry;

[0038] Figure 3 This is the block diagram of the sludge treatment system;

[0039] Figure 4 This is a schematic diagram of the structure of a titanium-based nano-coated electrode plate;

[0040] Figure 5 The flowchart of semiconductor wastewater treatment and regeneration method is as follows;

[0041] Marked in the figure: 1. Honeycomb titanium-based nano-coated electrode plate. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0043] A semiconductor industry wastewater treatment and regeneration system, characterized in that it includes the following connected in sequence: a quality pretreatment device, equipped with a pH / ORP online monitoring and sorting module and an automatic dosing unit; a three-dimensional electro-flocculation reactor, comprising a honeycomb titanium-based nano-coated electrode plate 1 and an ultrasonic descaling module; an intelligent membrane separation unit, composed of an acid- and alkali-resistant ceramic membrane component and an anti-pollution RO membrane component connected in series, and an automatic cleaning system with integrated multi-parameter feedback; an EDI deep purification device, whose outlet is connected to an ultrapure water storage tank; wherein the system also includes an AI control module based on an LSTM neural network to adjust the operating parameters of each unit in real time.

[0044] In this embodiment, the pH / ORP online monitoring and sorting module is used to monitor the pH value and oxidation-reduction potential (ORP) of the wastewater in real time, and classify the wastewater into different types according to these parameters, such as fluorine-containing wastewater, organic wastewater and grinding wastewater. Through online monitoring, it is ensured that the wastewater enters the appropriate treatment channel, which improves the pertinence and efficiency of the treatment and avoids interference between different types of pollutants; the automatic dosing unit is used to automatically add an appropriate amount of chemical agents, such as Ca(OH)2, according to the pH / ORP monitoring results, and automatically adjust the chemical properties of the wastewater to achieve the optimal treatment conditions, reduce manual operations, and improve the accuracy and consistency of the treatment; the honeycomb titanium-based nano-coated electrode plate 1 of the three-dimensional electroflocculation reactor is used to provide an efficient electrochemical reaction surface. The active coating of the electrode plate is composed of RuO2 and IrO2 in a molar ratio of 3:1, which increases the effective surface area. By increasing the electrode surface area, it is increased by 220 compared with the traditional flat electrode. %, which improves the efficiency of the electrocoagulation reaction and promotes the removal or conversion of heavy metal ions and organic matter; the ultrasonic descaling module is used to prevent scaling on the electrode plate surface. Through ultrasonic vibration, the deposits on the electrode surface are removed to maintain the high efficiency of the electrode and extend the service life of the equipment; the acid-alkali resistant ceramic membrane assembly of the intelligent membrane separation unit is used as a preliminary filtration layer to remove larger particles and some organic matter in the wastewater. The acid-alkali resistant ceramic membrane can work under extreme pH conditions, providing a highly durable filtration solution and reducing the frequency of membrane replacement; the anti-fouling RO membrane assembly is used to further remove dissolved salts and tiny particles. The anti-fouling RO membrane is designed to reduce membrane fouling, improve treatment efficiency and membrane life, so that the system can operate continuously and efficiently; the transmembrane pressure difference sensor in the automatic cleaning system is used to monitor the operating status of the membrane system with an accuracy of ±0.01MPa to ensure timely detection and treatment of membrane blockage; the working pressure of the backwash module is 0.2~0.5MPa, and the membrane surface is cleaned by reverse water flow to reduce the accumulation of pollutants; the chemical cleaning liquid circulation unit is equipped with a pH adaptive adjustment device to perform chemical cleaning as needed to restore the performance of the membrane, and automatically start the cleaning process through multi-parameter feedback, such as turbidity and transmembrane pressure difference, to keep the membrane clean, extend its service life, and ensure the continuous and efficient operation of the system; the ion exchange membrane stack of the EDI deep purification device adopts a bipolar membrane structure for electrodeionization (EDI) treatment, and removes ions in the water by electrochemical means. The resistivity of the produced water reaches ≥18MΩ·cm, which meets the demand for high-purity water in semiconductor production; the AI ​​control module is based on the LSTM neural network and is used to adjust the operating parameters of each processing unit in real time, such as current density, ozone dosage, etc. By collecting and analyzing data such as fluoride ion concentration, COD value, and transmembrane pressure difference, and using the deep learning ability of the LSTM neural network, the processing parameters are dynamically optimized to achieve a 20% to 30% reduction in reagent consumption, thereby improving the economy and environmental friendliness of the system operation; the overall system functions efficiently, and through quality pretreatment, electrocoagulation, membrane separation, and EDI deep purification, the system can efficiently treat complex sewage in the semiconductor industry; in terms of intelligent operation, the combination of AI control modules and automation systems makes the entire treatment process more intelligent, reduces manual intervention, and improves the reliability and operating efficiency of the system; in terms of resource reuse, the treated ultrapure water is directly used in semiconductor production, achieving efficient reuse of water resources and reducing fresh water consumption and wastewater discharge. .

[0045] The active coating of the titanium-based nano-coated electrode plate is composited with RuO2 and IrO2 in a molar ratio of 3:1.

[0046] In this embodiment, the effective surface area of ​​the electrode plate is increased by 220% compared with the traditional flat plate electrode.

[0047] The quality separation pretreatment device includes: a fluorine-containing wastewater diversion channel equipped with a Ca(OH)2 automatic dosing mechanism; an organic wastewater diversion channel with an ozone pre-oxidation contact tank; and a grinding wastewater diversion channel equipped with a micro-nano bubble flotation separator.

[0048] In this embodiment, the purpose of the design of the quality pretreatment device is to perform preliminary classification and pretreatment according to the properties of the wastewater before it enters the next treatment stage, so as to improve the treatment efficiency and effect of the entire system; the fluorine-containing wastewater diversion channel is used to specifically treat fluorine-containing semiconductor wastewater. Fluoride is common in semiconductor production and requires special treatment. It is equipped with a Ca(OH)2 automatic dosing mechanism. By automatically adding calcium hydroxide, the pH value of the wastewater is adjusted to 6.5-7.0, so that fluoride ions react with calcium ions to form calcium fluoride (CaF2) precipitation, thereby effectively removing fluoride ions in the water. This method not only has high removal efficiency, but also can reduce manual operation errors and reagent waste through automation; the organic wastewater diversion channel is used to treat semiconductor wastewater containing organic matter. These wastewaters usually need to be degraded by oxidation. An ozone pre-oxidation contact tank is provided. Ozone, as a strong oxidant, can effectively oxidize and degrade organic matter. Through ozone pretreatment, the structure of organic matter can be destroyed, and its removal efficiency in the subsequent treatment stage can be improved, while reducing the burden on the subsequent treatment units; the grinding wastewater diversion channel is used for grinding wastewater generated in the semiconductor production process. These wastewaters usually contain a large number of tiny solid particles. They are equipped with micro-nano bubble flotation separators. By generating micro-nano bubbles, these bubbles can effectively attach to solid particles, increase the buoyancy of the particles, and make them float to the water surface, thereby achieving solid-liquid separation. Micro-nano bubble flotation technology is more efficient than traditional flotation technology, can remove finer particles, improve the clarity of wastewater, and reduce the burden on subsequent treatment steps; through this quality-separation pretreatment device, the system can perform specific treatment for different types of pollutants at the beginning of the treatment, improving the pertinence and efficiency of the overall treatment. The diversion treatment of fluorine-containing wastewater, organic wastewater and grinding wastewater not only improves the accuracy of pollutant removal, but also optimizes the workload of subsequent treatment units, prolongs the service life of the equipment, and reduces the comprehensive treatment cost. This design reflects the intelligence and efficiency of modern sewage treatment systems and meets the needs of the semiconductor industry for high-standard environmental treatment.

[0049] The automatic cleaning system of the intelligent membrane separation unit includes: a transmembrane pressure difference sensor with a detection accuracy of ±0.01MPa; a backwash module with a working pressure of 0.2 to 0.5MPa; a chemical cleaning liquid circulation unit equipped with a pH adaptive adjustment device.

[0050] In this embodiment, the automatic cleaning system is an important part of the intelligent membrane separation unit, which is designed to maintain the clean state of the membrane assembly, prevent membrane clogging, extend the service life of the membrane, and maintain the efficient operation of the system; the transmembrane pressure difference sensor is used to monitor the changes in the transmembrane pressure difference during membrane separation, with a high-precision detection capability of ±0.01MPa, and can monitor the slight changes in the pressure difference during membrane filtration in real time. By monitoring the transmembrane pressure difference, it can be determined whether the membrane is blocked or contaminated, and a trigger signal for cleaning can be provided. When the transmembrane pressure difference exceeds the set threshold, such as 0.8-1.2MPa, the system will automatically start the cleaning program to prevent further clogging of the membrane and ensure the membrane separation efficiency; the backwash module flushes the membrane surface through reverse water flow to achieve the purpose of removing pollutants on the membrane surface. The working pressure is set between 0.2 and 0.5MPa, which can flush away pollutants attached to the membrane surface through the force of reverse water flow without damaging the membrane. The backwashing frequency is usually set to once every 30 to 60 minutes. This regular backwashing can effectively prevent the accumulation of pollutants, maintain the permeability of the membrane, and reduce the risk of membrane clogging; the chemical cleaning liquid circulation unit is used to use chemical cleaning liquid for deep cleaning when backwashing cannot completely remove pollutants. It is equipped with a pH adaptive adjustment device, which can automatically adjust the pH value of the cleaning liquid according to the nature of the pollutants to achieve the best cleaning effect. Chemical cleaning liquid can effectively remove stubborn pollutants that are difficult to remove by physical methods, such as biofilms and sediments. Through the circulation system, the chemical cleaning liquid can be used repeatedly, which improves the cleaning efficiency, reduces the use of chemical agents, and reduces operating costs. The pH adaptive adjustment device ensures the safety and effectiveness of the cleaning process and prevents membrane damage caused by improper pH value; through the synergistic effect of these three parts, the automatic cleaning system of the intelligent membrane separation unit can achieve continuous and efficient operation of the membrane assembly. The transmembrane pressure difference sensor provides real-time monitoring, the backwash module performs daily maintenance, and the chemical cleaning liquid circulation unit performs deep cleaning when necessary. This design not only improves the efficiency of membrane separation, but also extends the service life of the membrane and reduces maintenance costs, reflecting the intelligence and automation level of modern sewage treatment systems.

[0051] The ion exchange membrane stack of the EDI deep purification device adopts a bipolar membrane structure, and the resistivity of produced water is ≥18MΩ·cm.

[0052] In this embodiment, the EDI (electrodeionization) deep purification device is a key device for final purification in the wastewater treatment and regeneration system of the semiconductor industry. It removes ions in water through the electrodeionization technology to produce high-purity ultrapure water; the ion exchange membrane stack adopts a bipolar membrane structure in which the bipolar membrane structure is used to decompose water molecules under the action of an electric field and promote ion migration, thereby achieving deep deionization. Its function is to decompose water molecules: the bipolar membrane is composed of a cation exchange layer and an anion exchange layer. Under the action of the electric field, water molecules are decomposed into H at the interface of the bipolar membrane.+ (hydrogen ion) and OH - (hydroxide ions). This decomposition process provides continuous ion exchange capacity without the need for regeneration of traditional ion exchange resins; Ion migration: Driven by the electric field, cations in the solution (such as Na + ,Ca 2+ etc.) move toward the cathode through the cation exchange layer, while anions (such as Cl - ,SO4 2- Etc.) move to the anode through the anion exchange layer. This migration process effectively removes ions from the water and improves the purity of the water; Continuous operation: Unlike the traditional ion exchange resin regeneration process, the EDI system can achieve continuous operation using a bipolar membrane structure, which greatly simplifies the operating process and reduces downtime and manual maintenance; High-efficiency deionization: Through the structural design of the bipolar membrane, the EDI device can remove almost all dissolved ions and achieve extremely high water quality standards. The resistivity of the produced water is ≥18MΩ·cm, which meets the high requirements of semiconductor production for ultrapure water. This high-resistivity water contains almost no conductive ions, ensuring the cleanliness and product quality of the production process; By adopting a bipolar membrane structure, the EDI deep purification device not only improves the deionization efficiency, but also provides a stable and continuous ultrapure water production capacity, which is suitable for the high standards of water quality in the semiconductor industry. The application of this technology significantly reduces the use of chemical agents, saves regeneration costs, and reduces waste liquid discharge, playing a positive role in environmental protection.

[0053] A semiconductor wastewater treatment and regeneration method based on a semiconductor industry wastewater treatment and regeneration system, the method comprising the following steps: S1. Classifying wastewater into fluorine-containing wastewater, organic wastewater and grinding wastewater through an online monitoring sorting module; S2. Adding Ca(OH)2 to the fluorine-containing wastewater to a pH of 6.5-7.0 to form CaF2 precipitation; S3. Controlling the current density in the three-dimensional electrocoagulation treatment stage to 15-50A / m 2 , and inject ozone 10-200 mg / L at the same time; S4. The intelligent membrane system switches the cleaning mode according to the feedback from the turbidity sensor; S5. The EDI device produces ultrapure water that is reused in the wafer cleaning process.

[0054] In this embodiment, S1. The wastewater is classified into fluorine-containing wastewater, organic wastewater and grinding wastewater by an online monitoring and sorting module to ensure that the wastewater is classified and treated according to its pollution characteristics, thereby improving the pertinence and efficiency of the treatment. The pH / ORP online monitoring and sorting module is used to monitor the properties of the wastewater in real time and guide it to different treatment channels, including a fluorine-containing wastewater diversion channel, an organic wastewater diversion channel and a grinding wastewater diversion channel, so as to prepare for subsequent specific treatment; S2. Ca(OH)2 is added to the fluorine-containing wastewater to pH=6.5-7.0 to form a CaF2 precipitate, which is used to remove fluoride ions from the fluorine-containing wastewater. By automatically adding Ca(OH)2, the pH value of the wastewater is adjusted to 6.5-7.0, so that fluoride ions react with calcium ions to form calcium fluoride (CaF2) precipitate, thereby effectively reducing the fluoride content in the water. This method not only removes fluoride ions efficiently, but also reduces operating errors and reagent waste through automated control; S3. The current density is controlled at 15-50A / m in the three-dimensional electrocoagulation treatment stage. 2 , while injecting 10-200 mg / L of ozone for electrochemical treatment and ozone oxidation to further remove pollutants; electrocoagulation treatment: by controlling the current density at 15-50 A / m 2 , using honeycomb titanium-based nano-coated electrode plates for electrochemical reactions to remove metal ions, organic matter and other pollutants in water; the high surface area of ​​the electrode plates increases the treatment efficiency; ozone injection: 10-200 mg / L of ozone is injected at the same time, and the strong oxidizing property of ozone is used for catalytic oxidation to degrade difficult-to-degrade organic matter, thereby improving the overall treatment effect; S4. The intelligent membrane system switches the cleaning mode according to the feedback from the turbidity sensor to maintain the efficient operation of the membrane system and prevent membrane clogging. The intelligent membrane separation unit automatically switches to the appropriate cleaning mode, such as backwashing or chemical cleaning, according to the real-time feedback data from the turbidity sensor to ensure the cleanliness and permeability of the membrane components; such automated operations reduce manual intervention and improve the operating efficiency of the system ; S5. The ultrapure water produced by the EDI device is reused in the wafer cleaning process to produce ultrapure water for high-demand semiconductor production processes. Through the EDI deep purification device, almost all ions in the water are removed to produce ultrapure water with a resistivity of ≥18MΩ·cm; this ultrapure water is directly reused in the wafer cleaning process, which meets the demand for clean water in semiconductor production, realizes the recycling of wastewater, reduces the use of fresh water, and reduces production costs and environmental impacts; through the above steps, this method realizes the efficient treatment and regeneration of wastewater in the semiconductor industry, combines multiple technologies such as physics, chemistry, electrochemistry and membrane separation, ensures the thoroughness of treatment and the high standards of recycled water quality, and meets the dual requirements of semiconductor production for environmental protection and high-purity water.

[0055] The operating temperature of the ozone catalytic oxidation reactor in step S3 is 35-45° C., and the hydraulic retention time is 20-40 min.

[0056] In this embodiment, the working temperature is 35-45°C to optimize the efficiency of the ozone catalytic oxidation reaction. Within the temperature range of 35-45°C, the oxidizing ability of ozone is enhanced, the reaction rate is accelerated, and it is beneficial to the decomposition and oxidation process of organic matter; the appropriate temperature condition can improve the reaction efficiency between ozone and organic matter, making the reaction more thorough, while avoiding the excessively fast ozone decomposition rate that may be caused by excessively high temperature, thereby wasting ozone resources; by controlling within this temperature range, it can be ensured that the reaction is carried out under efficient and economical conditions; the hydraulic retention time of 20-40 minutes is used to ensure that the wastewater is fully in contact with the ozone in the reactor to achieve the best treatment effect. The hydraulic retention time (HRT) is the time that the wastewater stays in the reactor, which directly affects the time that the ozone contacts and reacts with the pollutants in the water; 20 The residence time of 20 to 40 minutes provides enough time for ozone to fully oxidize and degrade organic pollutants and other difficult-to-degrade substances in the water; the selection of this time range is based on the reaction kinetics of ozone, ensuring sufficient reaction time in the reactor while avoiding energy waste or decreased reaction efficiency caused by excessive residence time; through this design, the system can achieve efficient pollutant removal within a reasonable time, ensuring the quality and efficiency of the treatment; by setting the operating temperature at 35 to 45°C and the hydraulic retention time at 20 to 40 minutes, the ozone catalytic oxidation reactor plays a key role in step S3 and achieves effective treatment of difficult-to-degrade organic matter; this precise parameter control not only improves the treatment efficiency, but also optimizes resource utilization, reflecting the scientific and economic nature of the treatment process.

[0057] The transmembrane pressure difference control threshold of the intelligent membrane separation unit is 0.8~1.2MPa, and the backwash frequency is every 30~60 minutes.

[0058] In this embodiment, the transmembrane pressure difference control threshold is 0.8~1.2MPa, which is used to monitor and control the pressure in the membrane filtration process to prevent membrane clogging and performance degradation. To prevent clogging: When the transmembrane pressure difference (TMP) reaches or exceeds the threshold of 0.8~1.2MPa, it indicates that the membrane may begin to be clogged or contaminated, affecting the filtration efficiency; at this time, the system will trigger the automatic cleaning program to ensure the cleanliness and long-term performance of the membrane; Efficiency maintenance: By keeping the transmembrane pressure difference within this range, the system can maintain high flux and high efficiency of the membrane while effectively removing pollutants, avoiding membrane damage caused by excessive pressure or poor treatment effect caused by too low pressure; Automatic control: This threshold setting enables the system to automatically manage the operating status of the membrane, reduce manual intervention, and improve the ease of operation and reliability of the system; The backwashing frequency is every 30 to 60 minutes / time for regular cleaning of the membrane surface to prevent the accumulation of pollutants and maintain the permeability of the membrane. Regular cleaning: By setting it to be performed every 30 to 60 minutes After one backwash, the system can regularly remove pollutants attached to the membrane surface to prevent membrane blockage caused by long-term accumulation of pollutants; improve life: regular backwashing not only maintains the permeability of the membrane, but also extends the service life of the membrane, reducing the frequency and cost of replacing membrane components; efficiency optimization: backwashing can effectively restore the filtration performance of the membrane, ensuring that after each backwash, the membrane can filter at an efficiency close to the initial state and maintain the stability of the treatment process; save resources: this frequency backwashing design not only ensures the cleanliness of the membrane, but also takes into account the conservation of water resources and energy, avoiding the waste of resources that may be caused by frequent backwashing; by setting the transmembrane pressure difference control threshold to 0.8~1.2MPa and the backwashing frequency to every 30~60 minutes / time, the intelligent membrane separation unit can efficiently and intelligently manage the operating status of the membrane, ensure the effect of sewage treatment, while extending the service life of the membrane and reducing maintenance costs; this automated control strategy reflects the high degree of integration and optimization of modern sewage treatment technology.

[0059] The polar water circulation flow rate of the EDI deep purification device is 10% to 15% of the produced water flow rate, and the polar chamber pressure difference is maintained at 0.05 to 0.1 MPa.

[0060] In this embodiment, the electrode water circulation flow rate is 10% to 15% of the produced water flow rate, which is used to maintain the normal working environment of the ion exchange membrane stack in the EDI system and ensure the efficient deionization. Ion migration: The electrode water (also called electrode water) circulates in the system, providing a continuous ion transmission path; by controlling the electrode water circulation flow rate between 10% and 15% of the produced water flow rate, sufficient flow is ensured to carry away the H generated in the electrode reaction. + and OH -ions, preventing these ions from accumulating in the membrane stack, maintaining the efficiency of the ion exchange process; system stability: appropriate polar water circulation flow helps to maintain the stable operation of the system, avoids ion accumulation caused by too low polar water flow or unnecessary energy consumption caused by too high polar water flow, and optimizes the operating efficiency of the system; water quality control: through this flow setting, the continuity and stability of the deionization process are ensured, and high-quality ultrapure water is produced; the polar chamber pressure difference is maintained at 0.05~0.1MPa to control the polar chamber pressure difference in the EDI system to ensure the structural integrity and normal function of the ion exchange membrane stack and prevent membrane damage: the polar chamber pressure difference is controlled between 0.05~0.1MPa, which can prevent damage to the membrane structure due to excessive pressure or reduced efficiency due to too low pressure; this The setting of pressure difference ensures the smooth migration of ions in the membrane stack while protecting the physical structure of the membrane; optimizes performance: by maintaining an appropriate pressure difference, the system can operate under optimal conditions, ensuring the performance of the ion exchange membrane and improving the deionization efficiency; safe operation: this pressure difference control also ensures the safe operation of the EDI device, reduces the risk of system failure due to abnormal pressure, and improves the reliability of the system; by setting the polar water circulation flow rate to 10% to 15% of the produced water flow rate and maintaining the polar chamber pressure difference at 0.05 to 0.1 MPa, the EDI deep purification device can operate under efficient and safe conditions to produce ultrapure water that meets the high standards of the semiconductor industry; this precise parameter control reflects the advancement and practicality of EDI technology in water treatment.

[0061] The AI ​​control module collects fluoride ion concentration, COD value and transmembrane pressure difference data in real time, dynamically optimizes the coupling parameters of current density and ozone dosage, and reduces the agent consumption by 20% to 30%.

[0062] In this embodiment, the key parameters of the system operation are obtained by real-time collection of fluoride ion concentration, COD value and transmembrane pressure difference data, and the changes in the wastewater treatment process are monitored in real time. Fluoride ion concentration: real-time monitoring of the fluoride ion content in the wastewater helps the system to determine the effect of fluoride-containing wastewater treatment, and adjusts the dosage of Ca(OH)2 according to actual conditions to optimize the fluoride ion removal efficiency; COD value (chemical oxygen demand): by monitoring the COD value, the removal of organic matter can be evaluated; the COD value directly reflects the concentration of organic pollutants in the wastewater, and the system can dynamically adjust the dosage of ozone according to the change of COD value to ensure that there is Thoroughness of organic matter degradation; Transmembrane pressure difference: monitor the changes in transmembrane pressure difference and provide feedback for the operating status of the membrane system; when the transmembrane pressure difference increases, it may indicate that the membrane is blocked or contaminated, and the cleaning frequency or method needs to be adjusted; when the transmembrane pressure difference is too low, it may indicate that the membrane system is inefficient and the operating parameters need to be optimized; Dynamic optimization of the coupling parameters of current density and ozone dosage is used to adjust the treatment parameters according to real-time data to improve treatment efficiency, reduce energy consumption and reagent consumption, and current density optimization: In the three-dimensional electrocoagulation treatment stage, the AI ​​control module dynamically adjusts the current density by 15 to 50 A / m according to the real-time data of fluoride ion concentration and COD value. 2 , to ensure the efficiency of the electrochemical reaction while avoiding energy waste; ozone dosage optimization: combined with the real-time changes in COD values, the AI ​​module adjusts the ozone dosage by 10-200 mg / L to just meet the needs of organic matter degradation and avoid waste of resources caused by excessive use of ozone; coupling optimization: by coupling the adjustment of current density and ozone dosage, the AI ​​control module can find the best treatment conditions, so that electrochemical treatment and ozone catalytic oxidation work together to improve the overall treatment efficiency; reduce the consumption of reagents by 20% to 30% to reduce the use of reagents through intelligent control and reduce treatment costs. Through the above dynamic optimization In the process, the AI ​​control module can accurately control the amount of reagents used, reduce unnecessary reagent addition, and achieve a 20% to 30% reagent saving; this not only reduces treatment costs, but also reduces the potential impact of chemical reagents on the environment, while maintaining or improving treatment effects; by real-time collection of key data and dynamic optimization of treatment parameters, the AI ​​control module significantly improves the intelligence level of wastewater treatment and regeneration systems in the semiconductor industry; it reduces operating costs by reducing the amount of reagents used, while enhancing the system's treatment efficiency and environmental friendliness; the application of this technology demonstrates the great potential of artificial intelligence in environmental protection and industrial wastewater treatment.

[0063] In this embodiment, the inlet water parameters are: fluoride ion 800 mg / L, pH=2.5, COD=1500 mg / L.

[0064] Treatment process: Ca(OH)2 is added to the separation module until pH=6.8 to generate CaF2 precipitation; the current density in the electrocoagulation stage is 25A / m 2 , ozone dosage 80mg / L; ceramic membrane flux maintained at 35L / (m·h), backwash cycle 45 minutes / time; treatment results: fluoride ion ≤0.8mg / L, COD ≤50mg / L.

[0065] In other embodiments, water inlet parameters: SS = 5200 mg / L, SiO2 particle size 80-120 nm; micro-nano bubble flotation removes 90% of suspended solids; the intelligent membrane system triggers chemical cleaning when it detects a transmembrane pressure difference of 1.05 MPa; the EDI device chamber pressure difference is controlled at 0.08 MPa; regenerated water quality: resistivity 18.2 MΩ·cm, TOC <5 ppb; regenerated water quality: resistivity 18.2 MΩ·cm, TOC <5 ppb.

[0066] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A semiconductor industry wastewater treatment and regeneration system, characterized in that: Including the following connected in sequence: The quality pretreatment device is equipped with a pH / ORP online monitoring and sorting module and an automatic dosing unit; A three-dimensional electro-flocculation reactor, comprising a honeycomb titanium-based nano-coated electrode plate and an ultrasonic descaling module; Intelligent membrane separation unit, composed of acid-alkali resistant ceramic membrane components and anti-pollution RO membrane components in series, and integrated with multi-parameter feedback automatic cleaning system; The EDI deep purification device has its water outlet connected to the ultrapure water storage tank; Among them, the system also includes an AI control module based on LSTM neural network to adjust the operating parameters of each unit in real time.

2. A semiconductor industry wastewater treatment and regeneration system according to claim 1, characterized in that: The active coating of the titanium-based nano-coated electrode plate is composited with RuO2 and IrO2 in a molar ratio of 3:

1.

3. A semiconductor industry wastewater treatment and regeneration system according to claim 1, characterized in that: The quality separation pretreatment device comprises: Fluoride-containing wastewater diversion channel is equipped with Ca(OH)2 automatic dosing mechanism; The organic wastewater diversion channel is equipped with an ozone pre-oxidation contact tank; The grinding wastewater diversion channel is equipped with a micro-nano bubble flotation separator.

4. A semiconductor industry wastewater treatment and regeneration system according to claim 1, characterized in that: The automatic cleaning system of the intelligent membrane separation unit comprises: Transmembrane pressure difference sensor, detection accuracy ±0.01MPa; Backwash module, working pressure 0.2~0.5MPa; Chemical cleaning liquid circulation unit, equipped with pH self-adapting adjustment device.

5. A semiconductor industry wastewater treatment and regeneration system according to claim 1, characterized in that: The ion exchange membrane stack of the EDI deep purification device adopts a bipolar membrane structure, and the resistivity of produced water is ≥18MΩ·cm.

6. A semiconductor wastewater treatment and regeneration method, using a semiconductor industry wastewater treatment and regeneration system as described in any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Classify the wastewater into fluoride-containing wastewater, organic wastewater and grinding wastewater through an online monitoring and sorting module; S2. Add Ca(OH)2 to the fluoride-containing wastewater until the pH is 6.5-7.0 to form CaF2 precipitation; S3. The current density of the three-dimensional electrocoagulation treatment stage is controlled at 15 to 50 A / m 2 , while injecting ozone 10-200mg / L; S4. The smart membrane system switches the cleaning mode according to the feedback from the turbidity sensor; S5. The ultrapure water produced by the EDI device is reused in the wafer cleaning process.

7. A semiconductor wastewater treatment and regeneration method according to claim 6, characterized in that: The operating temperature of the ozone catalytic oxidation reactor in step S3 is 35-45° C., and the hydraulic retention time is 20-40 min.

8. A semiconductor wastewater treatment and regeneration method according to claim 6, characterized in that: The transmembrane pressure difference control threshold of the intelligent membrane separation unit is 0.8-1.2 MPa, and the backwashing frequency is once every 30-60 minutes.

9. A semiconductor wastewater treatment and regeneration method according to claim 6, characterized in that: The polar water circulation flow rate of the EDI deep purification device is 10% to 15% of the produced water flow rate, and the polar chamber pressure difference is maintained at 0.05 to 0.1 MPa.

10. A semiconductor wastewater treatment and regeneration method according to claim 6, characterized in that: The AI ​​control module dynamically optimizes the coupling parameters of current density and ozone dosage by collecting fluoride ion concentration, COD value and transmembrane pressure difference data in real time, thereby reducing the agent consumption by 20% to 30%.

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