Device for removing PFAS and micro-plastic in drinking water based on micro-nano bubble jet droplet enrichment

Abstract

The invention belongs to the technical field of drinking water purification, and particularly relates to a device for removing PFAS and micro-plastics in drinking water based on micro-nano bubble jet droplet enrichment. According to the device disclosed by the invention, the PFAS and the micro-plastics are captured by utilizing rising bubbles according to the enrichment characteristics of the PFAS and the micro-plastics on a gas-liquid interface and are brought to the liquid surface to form jet drops, so that the PFAS and the micro-plastics are removed; the system specifically comprises: an inlet water pretreatment unit used for preliminarily adsorbing PFAS in a water body; the air supply regulation and control unit is used for generating a large number of micro-bubbles to rise; the core reaction unit comprises a cylindrical reaction kettle body provided with an aeration assembly; the aerosol trapping unit is used for sucking in jet drops generated by bubble breakage and condensing and separating the jet drops; the intelligent control cabinet is used for collecting sensor data in real time and regulating and controlling the running states of the pump and the draught fan. The device is compact in structure, stable in running, low in energy consumption and capable of efficiently removing PFAS and micro-plastic in drinking water.

Description

Technical Field

[0001] The present invention belongs to the technical field of drinking water purification, and particularly relates to a device for removing PFAS and microplastics in drinking water based on micro-nano bubble droplet enrichment. Background Art

[0002] Traditional drinking water treatment plants relying on coagulation, flocculation and sedimentation processes are usually ineffective in removing short-chain PFAS (carboxylic acids < C8 or sulfonates < C6) and microplastics. Their removal rate of PFAS is often less than 50%, and the removal efficiency of 1–10 μm microplastics is usually even less than 2%.

[0003] To solve the above problems, the industrial community has currently tried to adopt a variety of advanced treatment technologies, but all face significant technical bottlenecks. Granular activated carbon (GAC) has a good adsorption effect on long-chain PFAS, but a weak adsorption effect on short-chain PFAS, resulting in rapid breakthrough of the adsorption bed layer and a significant decline in long-term operation performance. Although anion exchange resin (AER) can effectively remove short-chain PFAS, it is limited by early breakthrough, difficult resin regeneration, and high medium and operation costs. High-pressure membrane processes such as nanofiltration and reverse osmosis have extremely high removal rates, but consume a large amount of energy and produce highly concentrated wastewater that is difficult to treat, and may even release additional microplastic fragments during operation. In addition, although traditional foam separation technology performs excellently in the treatment of high-concentration waste liquid, in the drinking water treatment scenario, due to the extremely low concentration of surfactants, it is difficult to maintain a stable foam layer, and the removal efficiency of short-chain PFAS is low.

[0004] In view of the limitations of the prior art, the present invention proposes a new removal strategy based on the phenomenon of droplet generation caused by bubble rupture. Different from the processes relying on a stable foam layer, this technology utilizes the enrichment characteristics of PFAS and microplastics at the gas-liquid interface. When the bubble reaches the water surface and ruptures, the upward liquid jet induced by the collapse of the cavity will break into droplets. Due to the low surface tension and high surface activity of long-chain PFAS, it is extremely easy to concentrate at the interface and enter the jet droplets, and its enrichment factor can be as high as several thousand times; at the same time, the rising bubbles can effectively capture microplastics and bring them to the interface. Although there have been studies on aerosol-mediated treatment, most of them focus on high ionic strength or wastewater conditions, lacking a low-cost systematic solution for the synchronous removal of PFAS with different chain lengths and microplastics in the low-concentration environment of drinking water. Therefore, it is of great application value to develop an efficient, economical and scalable purification device using the principle of interfacial enrichment. Summary of the Invention

[0005] The purpose of the present invention is to provide a device for removing PFAS and microplastics in drinking water with a compact structure, stable operation, low energy consumption and high efficiency.

[0006] The device for removing PFAS and microplastics from drinking water based on micro-nano bubble jet droplet enrichment provided by the present invention utilizes the enrichment characteristics of PFAS and microplastics at the gas-liquid interface. When the bubbles reach the water surface and burst, the upward liquid jet induced by the collapse of the cavity will break into droplets. Since long-chain PFAS (carboxylic acid <C8 or sulfonate <C6) has low surface tension and high surface activity, it is extremely easy to enrich at the interface and enter the jet droplets, and its enrichment factor can be as high as thousands of times. At the same time, the rising bubbles can effectively capture microplastics and bring them to the interface, facilitating removal. Its structure includes: an inlet water pretreatment unit 1, a core reaction unit 6, a gas supply regulation unit 24, an aerosol capture unit 28, and an intelligent control cabinet 34. Among them:

[0007] The inlet water pretreatment unit 1 is used for preliminarily adsorbing short-chain PFAS in the water body and includes: a raw water tank 2, an inlet water peristaltic pump 3, a pretreatment column 4, and an inlet water ball valve 5. The raw water tank 2 is connected to the inlet water peristaltic pump 3 through a pipeline. The outlet of the peristaltic pump 3 is connected to the bottom inlet of the pretreatment column 4 through a hose. The top outlet of the pretreatment column 4 is connected to the side inlet at the bottom of the core reaction unit 6 through a pipeline equipped with an inlet water ball valve 5. The pretreatment column 4 is filled with gel-type strong basic anion exchange resin (AER).

[0008] The core reaction unit 6 is the core component of this device and includes a vertically placed transparent cylindrical reaction kettle body 7. The bottom of the reaction kettle body 7 is provided with a detachable micro-nano aeration component 8, and the core of this component is a quartz microporous filter plate clamped and fixed by upper and lower flanges. A number of sensor interfaces and a water outlet with a liquid level adjustment function are provided on the side wall of the kettle body.

[0009] Specifically, there is a lower flange base 9 at the bottom of the reaction kettle body 7. There is a depression in the center of the lower flange base 9 to form an air inlet chamber 10. A first-layer silicone sealing washer 12, a quartz microporous filter plate 11, and a second-layer silicone sealing washer 12 are sequentially placed above the air inlet chamber 10. The uppermost is an upper pressing ring flange 13. This sandwich-type clamping and sealing structure can ensure that gas can only enter the upper water body through the micropores of the quartz microporous filter plate 11, generating uniform micro-nano bubbles and preventing edge air leakage.

[0010] On the side wall of the reaction kettle body 7 at heights of 650 - 700 mm and 350 - 400 mm from the bottom, two sensor interfaces are respectively opened: an RH sensor probe 16 and a temperature sensor probe 17. The two sensor probes are respectively sealed and inserted into the kettle body through waterproof cable connectors 18, and the probe signal wires are connected to the intelligent control cabinet 34.

[0011] To precisely control the liquid level H (marked 23), the reactor body 7 employs an overflow system. A bottom outlet 20 is located at a certain distance from the bottom (e.g., 550-600mm), connected externally to a U-shaped adjustable overflow pipe 21. The overflow pipe consists of two sections of UPVC pipe connected by a union nut. By rotating and adjusting the height of the highest point of the overflow pipe, a stable liquid level within the reactor body is precisely set, ensuring that the distance between the liquid level and the lower edge of the top gas collecting hood remains consistently within the designed range of 3-5cm. The treated water flows into the collection tank through the overflow pipe.

[0012] The air supply control unit 24 is used to provide a stable flow of clean air or nitrogen to the micro-nano aeration components. The air supply control unit 24 includes an oil-free air compressor 25, a gas mass flow controller (MFC) 26, and a one-way valve. The oil-free air compressor 25 is used to provide compressed air, which enters the bottom air intake chamber 10 after being stabilized by the gas mass flow controller 26. It passes through the quartz microporous filter plate 11 and generates a large number of microbubbles that rise.

[0013] The aerosol collection unit 28 is located in the gas phase space at the top of the reactor body and is used to draw in and condense droplets generated by bubble bursting. It includes a stainless steel conical gas collection hood 29, which covers the top opening of the reactor body 7. The bottom diameter of the conical gas collection hood 29 is the same as that of the reactor body. The top outlet of the conical gas collection hood is welded with an NW25 vacuum flange interface, which is connected to the tangential inlet of a cyclone separator 31 through a negative pressure resistant connecting hose 30 with an embedded metal wire skeleton. The bottom of the cyclone separator 31 is connected to a pollutant collection bottle 32, and the top outlet is connected to a negative pressure suction pump 33.

[0014] The intelligent control cabinet 34 integrates a PLC controller, which collects sensor data in real time and regulates the operating status of the pump and fan.

[0015] The working process of the PFAS and microplastic removal device provided by the present invention is as follows:

[0016] Step 1: System initialization and parameter setting; Connect the power supply to the intelligent control cabinet 34, and the device enters standby mode; Set the operating parameters through the PLC human-machine interface, including: the flow rate setting value of the water inlet peristaltic pump 3, the initial flow rate setting value of the gas mass flow controller (MFC) 26, and the pumping rate of the negative pressure suction pump 33; At the same time, set the monitoring thresholds for temperature and relative humidity (RH) (e.g., temperature 15-25℃, RH > 80%) as a reference for environmental steady state;

[0017] Step 2: Water intake and pretreatment; Start the water intake peristaltic pump 3, and the water to be treated in the raw water tank 2 is pumped into the pretreatment column 4 through the pipeline; The water flows through the column filled with strong alkaline anion exchange resin (AER), and during this process, 80%~90% of PFAS is efficiently adsorbed and removed by the resin; The pretreated water enters the reactor body 7 from the side inlet at the bottom of the core reaction unit 6 through the top pipeline and the water intake ball valve 5; As the water intake continues, the liquid level in the reactor body gradually rises until it reaches the working liquid level (liquid level height H) set by the highest point of the external U-shaped adjustable overflow pipe 21. At this time, the liquid level is stably maintained at 3-5cm from the lower edge of the top conical gas collection hood 29;

[0018] Step 3: Micro-nano bubble generation and pollutant enrichment; After the liquid level stabilizes, the intelligent control cabinet 34 issues a command to start the gas supply regulation unit 24; The clean compressed air generated by the oil-free air compressor 25 enters the air inlet chamber 10 of the micro-nano aeration component 8 after being stabilized by the one-way valve 27 and the gas mass flow controller 26; After being buffered in the chamber, the gas is uniformly pressurized and passes through the micron-sized pores (1.2~2.0μm) of the quartz microporous filter plate 11, and is instantly sheared and dispersed above the quartz plate, generating a large number of bubbles with an average particle size of less than 50 μm; These microbubbles rise uniformly in a cloud-like manner in the reactor body 7; During the rising process, the bubbles efficiently capture microplastic particles in the water by utilizing the hydrophobic properties of the gas-liquid interface, while long-chain PFAS molecules with surfactant properties spontaneously adsorb and enrich on the bubble surface.

[0019] Step 4: Jet Droplet Generation and Aerosol Capture; When the microbubbles carrying pollutants rise to the gas-liquid interface, they rupture; At the moment of bubble rupture, the cavity at the bottom of the bubble collapses rapidly under the action of surface tension, generating an upward high-speed liquid jet; Due to the high concentration of long-chain PFAS and microplastics at the interface, the concentration of pollutants in these jet droplets is much higher than that in the bulk solution; At this time, the relative humidity (RH) sensor probe 16 monitors the humidity change in the gas phase space; At the same time, the aerosol capture unit 28 is in operation; The negative pressure suction pump 33 forms a negative pressure zone in the conical gas collection hood 29, which quickly sucks in the jet droplets that have just been generated and ejected into the gas phase space; The aerosol gas flow enters the cyclone separator 31 tangentially through the negative pressure resistant connecting hose 30; Under the action of centrifugal force, the droplets separate from the gas flow and slide down the wall to the pollutant collection bottle 32 at the bottom to form a high-concentration waste liquid, while the clean air is discharged from the top of the cyclone separator;

[0020] Step 5: Intelligent Feedback Control; Throughout the entire operation of the device, the intelligent control cabinet 34 performs precise control based on sensor feedback: the temperature sensor probe 17 monitors the system temperature in real time. Once it detects a drastic temperature fluctuation that may change the viscosity and surface tension of the water, thereby affecting bubble rupture, the PLC immediately issues an alarm or links external temperature control equipment to intervene; at the same time, the relative humidity (RH) sensor probe 16 is responsible for monitoring the stability of aerosol generation. If the RH value is too low (close to the ambient humidity), it indicates that the amount of droplets generated by bubble rupture is insufficient or the airflow is too large. The PLC will instruct to increase the opening of the gas mass flow controller 26 to increase the bubble flux; this closed-loop feedback mechanism based on environmental parameters effectively ensures that droplets are always generated and transported under optimal physical conditions;

[0021] Step 6: Water Discharge and Shutdown; After purification, the clean water enters the U-shaped adjustable overflow pipe 21 through the outlet 20 at the bottom, and overflows into the external water collection tank under gravity, achieving continuous water discharge; After the treatment task is completed, the system shuts down according to the preset logic: First, the inlet peristaltic pump 3 and the air supply control unit 24 are turned off, and after a delay of 30 seconds, the negative pressure suction pump 33 is turned off (ensuring that the residual aerosol in the pipeline is completely emptied); Finally, the drain valve 22 at the bottom of the reactor body is opened to drain the remaining water in the reactor, completing one treatment cycle.

[0022] The main technical features and functional advantages of this invention are as follows:

[0023] (1) Structured bubble generation: The quartz filter plate is fixed by the flange sealing structure to ensure that 100% of the gas escapes through the micropores, avoiding the generation of large bubbles that disturb the liquid surface due to edge leakage, and ensuring a stable flow of micro-nano bubbles and subsequent droplet generation efficiency.

[0024] (2) Precise liquid level control design: The adjustable height overflow water outlet structure is adopted to precisely control the distance between the gas-liquid interface and the top gas collection hood (optimal 3-5cm). This is the key mechanical guarantee to ensure that the droplets are effectively captured instead of falling back into the water.

[0025] (3) Modular connection: Standard quick-connect fittings, flanges or threaded connections are used between units, which facilitates disassembly, maintenance and cleaning, and improves the practicality of the device. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of the removal device for PFAS and microplastics enriched by micro-nano bubble droplets based on the present invention.

[0027] Figure 2 yes Figure 1 A partial cross-sectional magnified diagram of the micro-nano aeration component at the bottom of the core reaction unit.

[0028] Figure 3yes Figure 1 A schematic diagram of the sensor interface and outlet water level adjustment structure on the side of the reactor body. The left side shows details of the sensor installation, and the right side shows details of the overflow pipe adjustment.

[0029] Figure 4 yes Figure 1 A flowchart illustrating the equipment installation process of the central water inlet treatment unit.

[0030] Figure 5 yes Figure 1 A flowchart illustrating the equipment installation process of the aerosol capture unit.

[0031] Figure 6 yes Figure 1 A flowchart illustrating the equipment installation process of the gas supply control unit.

[0032] Figure 7 This is a flowchart illustrating the components controlled by the sensor group connected to the intelligent control cabinet.

[0033] Numbering in the diagram: 1-Inlet pretreatment unit; 2-Raw water tank; 3-Inlet peristaltic pump; 4-Pretreatment column (AER column); 5-Inlet ball valve; 6-Core reaction unit; 7-Reaction vessel body; 8-Micro-nano aeration component; 9-Lower flange base; 10-Air inlet chamber; 11-Quartz microporous filter plate; 12-Silicone sealing gasket; 13-Upper pressure ring flange; 14-Fixing bolt assembly; 15-Sensor assembly; 16-RH sensor probe; 17-Temperature sensor probe; 18-PG waterproof electrode 19-Cable connector; 20-Water outlet structure; 21-Bottom outlet; 22-Adjustable overflow pipe; 23-Drain valve; 24-Liquid level (H); 25-Gas supply control unit; 26-Oil-free air compressor; 27-Gas mass flow controller (MFC); 28-Check valve; 29-Aerosol collection unit; 30-Conical gas collection hood; 31-Negative pressure resistant connecting hose; 32-Cyclone separator; 33-Contaminant collection bottle; 34-Negative pressure suction pump; 35-Intelligent control cabinet (PLC). Detailed Implementation

[0034] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0035] Example: A miniaturized prototype device with a processing capacity of 10-20 L / h.

[0036] Device Construction: This invention constructs a laboratory-scale jet droplet enrichment (JDE) system.

[0037] The main body of this device is a vertical columnar reactor made of transparent acrylic material, with an inner diameter of 15 cm and a height of 80 cm. Micro-nano aeration components are integrated at the bottom of the reactor to release tiny bubbles with an average diameter of approximately 47 μm into the water. When the bubbles rise to the liquid surface and burst, a cyclone separator collecting unit located 3-5 cm above the liquid surface promptly captures the resulting contaminant-rich jet droplets. Furthermore, addressing the challenge of removing short-chain PFAS, the device employs an enhanced configuration (JDE+AER), which connects an anion exchange resin (AER) pretreatment unit in series at the front end of the jet enrichment system, significantly improving the overall purification efficiency through synergistic effects.

[0038] The main connection is as follows: the raw water tank 2 is connected to the inlet peristaltic pump 3 via a pipeline; the pump outlet is connected to the bottom inlet of the pretreatment column 4 via a hose; the top outlet of the pretreatment column 4 is connected to the side inlet at the bottom of the core reaction unit 6 via a pipeline equipped with an inlet ball valve 5. The air supply control unit 24 is connected to the micro-nano aeration component 8 at the bottom of the core reaction unit 6. The opening at the top of the core reaction unit 6 is connected to the aerosol collection unit 28.

[0039] 1. Detailed Structure and Connection of the Inlet Pretreatment Unit: The inlet peristaltic pump 3 is a model with precise flow rate adjustment (such as BT100-2J), and its inlet and outlet ends are connected by silicone hoses with an inner diameter of φ6mm and an outer diameter of φ9mm. The pretreatment column 4 is a transparent acrylic column with an inner diameter of φ25mm and a length of 300mm, filled with gel-type strong basic anion exchange resin (AER, such as Purolite A600) with a particle size of 0.5-1.0mm. The end caps of the pretreatment column 4 use G1 / 4-inch pipe thread interfaces, which are connected to the silicone hoses through quick-connect fittings for the initial adsorption of short-chain PFAS in the water.

[0040] 2. Mechanical Design of the Core Reaction Unit: The reactor body 7 is a custom-made transparent acrylic cylindrical tube with an inner diameter of φ150mm, a height of 800mm, and a wall thickness of 5mm, facilitating observation of the bubble state. A micro-nano aeration component 8 is installed at the bottom of the reactor body 7. This component is not a simple aeration head, but a precision flange clamping structure. It includes a stainless steel lower flange base 9, with a recessed center forming an air inlet chamber 10 with a height of 20mm. A stainless steel air inlet pipe with a φ6mm double-ferrule fitting is welded to the side opening of the air inlet chamber 10. Above the air inlet chamber 10, the first layer of silicone sealing gaskets 12 (Shore hardness A60, thickness 2mm), the core quartz microporous filter plate 11 (diameter φ160mm, thickness 5mm, average pore size specified as 1.5μm), and the second layer of silicone sealing gaskets 12 are placed sequentially. At the very top is an annular acrylic upper pressure ring flange 13. The upper pressure ring flange 13, two layers of sealing gaskets 12, quartz microporous filter plate 11, and lower flange base 9 are tightened and fixed by eight sets of M8 stainless steel fixing bolts 14 evenly distributed on the circumference. This sandwich-style clamping and sealing structure ensures that gas can only enter the water above through the micropores of the quartz microporous filter plate 11, generating uniform micro-nano bubbles and eliminating edge leakage.

[0041] To monitor the microenvironment for jet droplet generation, a monitoring interface is installed at a specific location in the reactor body 7. A relative humidity (RH) sensor probe 16, located in the gas phase space above the liquid surface, is used to monitor the ambient humidity in real time when bubbles burst and aerosols are generated. This prevents excessively low humidity from causing droplets to evaporate too quickly during transport, or from humidity saturation affecting separation efficiency. A temperature sensor probe 17 is installed on the side wall of the reactor body 7 (approximately 350-400 mm from the bottom) via a PG13.5 waterproof cable connector 18, extending into the water body to monitor the reaction temperature. Temperature directly affects the surface tension and viscosity of water, thus influencing the size and generation rate of the jet droplets. The signal lines of both probes are connected to the intelligent control cabinet 34. To accurately control the liquid level height H (i.e., mark 23), the reactor body 7 employs an overflow system. A bottom outlet 20 is located 600 mm from the bottom, and a U-shaped adjustable overflow pipe 21 is connected externally to this outlet. The overflow pipe consists of two UPVC pipe sections connected by a union nut. By rotating and adjusting the height of the highest point of the overflow pipe, a stable liquid level in the reactor can be precisely set, ensuring that the distance between the liquid level and the lower edge of the top gas collecting hood remains within the design requirement of 3-5 cm. The treated water flows into the water collection tank through the overflow pipe.

[0042] 3. Connection of the aerosol collection unit: The top of the reactor body 7 is open, and a stainless steel conical gas collection hood 29 is fitted on top. Its bottom diameter is the same as the reactor body, φ150mm, and the cone angle is 60 degrees. An NW25 vacuum flange interface is welded to the top outlet of the gas collection hood, which is quickly connected to the tangential inlet of the cyclone separator 31 via a negative pressure resistant connecting hose 30 (inner diameter φ25mm) with an embedded metal wire skeleton. The bottom of the cyclone separator is connected to a contaminant collection bottle 32, and the top outlet is connected to a negative pressure suction pump 33 (adjustable pumping speed, approximately 15-20 L / min).

[0043] 4. Specific processing procedure:

[0044] During system operation, the bubble generator continuously produces a large number of bubbles in the water. As these bubbles rise, they effectively capture PFAS and microplastics in the water. When the bubbles reach the water surface and burst, the collapse of the cavity at the bottom induces the formation of an upward high-speed liquid jet. Due to the high enrichment of long-chain PFAS and microplastics at the gas-liquid interface, they are immediately transferred into these tiny jet droplets. Subsequently, a cyclone separator located above the liquid surface draws in these jet droplets containing high concentrations of pollutants and condenses and collects them, thus completely separating the pollutants from the water. Addressing the difficulty in removing short-chain PFAS, an enhanced configuration (JDE+AER) pre-treats the water by passing it through a small amount of AER resin to adsorb most of the short-chain PFAS before it enters the JDE process to synergistically remove the remaining short-chain PFAS and microplastics.

[0045] 5. Processing Results

[0046] This invention underwent comprehensive testing and verification of the system in ultrapure water and Shanghai municipal tap water. The results showed that the removal efficiency in tap water was comparable to that in ultrapure water, demonstrating the stability of the device's performance in actual water substrates. After 40 minutes of treatment, the removal rate of long-chain PFAS exceeded 99%. For short-chain PFAS, which had a low removal rate (approximately 20%-53%) with the JDE system alone, the removal rate was successfully increased to over 90% by employing a JDE+AER combined process. Furthermore, the device achieved a removal rate of up to 99% for both 5 μm and 10 μm microplastics. The study also found that the presence of PFAS reduced surface tension, generating smaller bubbles, which in turn promoted the removal of 5 μm microplastics, demonstrating a unique synergistic purification effect.

[0047] This device exhibits significant advantages over traditional technologies such as granular activated carbon (GAC) or anion exchange resin (AER) alone. First, its simultaneous removal capability is extremely strong, overcoming the limitations of traditional coagulation and sedimentation processes in removing microplastics and PFAS, achieving a high efficiency of over 90%-99% removal of these two types of pollutants. Second, addressing the high cost of short-chain PFAS treatment, the JDE+AER coupled system utilizes the synergistic effect of jet enrichment for removing long chains and resin adsorption for short chains, reducing the material utilization rate (MUR) of resin by 90%, resulting in an estimated operating cost of only $0.13 / m³, far lower than traditional AER ($0.63 / m³) and GAC ($0.58 / m³) processes achieving equivalent removal efficiency. Furthermore, this process primarily relies on physical enrichment and separation, requiring no chemical reagents, and is environmentally friendly, producing a small volume of concentrated liquid that is easy to process later. In summary, this device has demonstrated significant advantages in terms of high efficiency, broad spectrum, and low cost in laboratory and tap water validation, and provides a highly competitive solution, especially in the treatment of recalcitrant short-chain PFAS.

Claims

1. A device for removing PFAS and microplastics from drinking water based on micro / nano bubble droplet enrichment, characterized in that, Utilizing the enrichment properties of PFAS and microplastics at the gas-liquid interface, when bubbles reach the water surface and burst, the upward liquid jet induced by cavity collapse breaks into droplets. Due to the low surface tension and high surface activity of long-chain PFAS, it is easy to enrich at the interface and enter the jet droplets, with enrichment factors reaching thousands of times. At the same time, rising bubbles can effectively capture microplastics and carry them to the interface, thus facilitating their removal. Its structure includes: an influent pretreatment unit (1), a core reaction unit (6), an air supply control unit (24), an aerosol collection unit (28), and an intelligent control cabinet (34); wherein: The inlet water pretreatment unit (1) is used for the initial adsorption of short-chain PFAS in the water body; it includes: raw water tank (2), inlet water peristaltic pump (3), pretreatment column (4), and inlet water ball valve (5); the raw water tank (2) is connected to the inlet water peristaltic pump (3) through a pipeline, the outlet of the peristaltic pump (3) is connected to the bottom inlet of the pretreatment column (4) through a hose, and the top outlet of the pretreatment column (4) is connected to the side inlet of the bottom of the core reaction unit (6) through a pipeline equipped with inlet water ball valve (5); the pretreatment column (4) is filled with gel-type strong basic anion exchange resin. The core reaction unit (6) includes a vertically placed transparent cylindrical reactor body (7); the bottom of the reactor body (7) is provided with a detachable micro-nano aeration component (8), which includes a quartz microporous filter plate clamped and fixed by upper and lower flanges; the side wall of the reactor body is provided with several sensor interfaces and a water outlet with liquid level adjustment function and a drain valve (22) located at the bottom. The gas supply control unit (24) is used to provide a stable flow of clean air or nitrogen to the micro-nano aeration components. The gas supply control unit (24) includes an oil-free air compressor (25) and a gas mass flow controller (26). The oil-free air compressor (25) is used to provide compressed air, which enters the bottom air inlet chamber (10) after being stabilized by the gas mass flow controller (26). It passes through the quartz microporous filter plate (11) and generates a large number of microbubbles that rise. The aerosol collection unit (28) is located in the gas phase space at the top of the reactor body and is used to draw in and condense the droplets generated by the bursting of bubbles. It includes a stainless steel conical gas collection hood (29), which covers the top opening of the reactor body (7). The bottom diameter of the conical gas collection hood (29) is the same as that of the reactor body. The top outlet of the conical gas collection hood is welded with an NW (25) vacuum flange interface, which is connected to the tangential inlet of an aerosol cyclone separator (31) through a negative pressure resistant connecting hose (30) with an embedded metal wire skeleton. The bottom of the cyclone separator (31) is connected to a pollutant collection bottle (32), and the top outlet is connected to a negative pressure suction pump (33). The intelligent control cabinet (34) integrates a PLC controller, which is used to collect sensor data in real time and regulate the operating status of the pump and fan.

2. The apparatus according to claim 1, characterized in that, In the core reaction unit (6), there is a lower flange base (9) at the bottom of the reactor body (7), and there is a recess in the center of the lower flange base (9) to form an air inlet chamber (10); the first layer of silicone sealing gasket (12), quartz microporous filter plate (11), and second layer of silicone sealing gasket (12) are placed in sequence above the air inlet chamber (10); the topmost part is an upper pressure ring flange (13); this sandwich-style clamping and sealing structure ensures that gas can only enter the water above through the micropores of the quartz microporous filter plate (11), generating uniform micro-nano bubbles and preventing edge leakage.

3. The apparatus according to claim 2, characterized in that, In the core reaction unit (6), two sensor interfaces are respectively provided on the side wall of the reactor body (7) at a height of 650-700 mm and 350-400 mm from the bottom: RH sensor probe (16) and temperature probe (17); the two sensor probes are respectively sealed and inserted into the reactor body through waterproof cable connectors (18), and the probe signal lines are connected to the intelligent control cabinet (34).

4. The apparatus according to claim 2, characterized in that, In the core reaction unit (6), the reactor body (7) adopts an overflow water discharge method. Specifically, a bottom water outlet (20) is provided at a distance of 550-600mm from the bottom. A U-shaped adjustable overflow pipe (21) is connected to the outside of the water outlet. The overflow pipe (21) consists of two UPVC pipes connected by a union nut. By rotating and adjusting the height of the highest point of the overflow pipe, the stable liquid level in the reactor body is precisely set to ensure that the distance between the liquid surface and the lower edge of the top gas collecting hood is stable within the design requirement of 3-5cm. The treated water flows into the water collection tank through the overflow pipe.

5. The apparatus according to any one of claims 1-4, characterized in that, The workflow is as follows: Step 1: System initialization and parameter setting; Connect the power supply of the intelligent control cabinet (34) and the device enters the standby state; Set the operating parameters through the PLC human-machine interface, including: the flow rate setting value of the water inlet peristaltic pump (3), the initial flow rate setting value of the gas mass flow controller (26), and the pumping rate of the negative pressure suction pump (33); At the same time, set the monitoring thresholds of temperature and relative humidity as a reference for the steady state of the environment; Step 2: Water intake and pretreatment; Start the water intake peristaltic pump (3), and the water to be treated in the raw water tank (2) is pumped into the pretreatment column (4) through the pipeline; The water flows from bottom to top through the column filled with strong alkaline anion exchange resin; During this process, 80%~90% of PFAS is adsorbed and removed by the resin; The pretreated water enters the reactor body (7) from the side inlet at the bottom of the core reaction unit (6) through the top pipeline and the water intake ball valve (5); As the water intake continues, the liquid level in the reactor body gradually rises until it reaches the working liquid level set by the highest point of the external U-shaped adjustable overflow pipe (21). At this time, the liquid level is stably maintained at 3-5cm from the lower edge of the top conical gas collection hood (29); Step 3: Generation of micro-nano bubbles and enrichment of pollutants; After the liquid level stabilizes, the intelligent control cabinet (34) issues an instruction to open the gas supply regulation unit (24); The clean compressed air generated by the oil-free air compressor (25) enters the air inlet chamber (10) of the micro-nano aeration component (8) after being stabilized by the one-way valve (27) and the gas mass flow controller (26); After being buffered in the chamber, the gas is uniformly pressurized and passes through the micron-sized pores of the quartz microporous filter plate (11), and is instantly sheared and dispersed above the quartz plate, generating a large number of micro-nano bubbles with an average particle size of less than 50 μm; These micro-bubbles rise uniformly in the reaction vessel (7) in a cloud-like manner; During the rising process, the micro-bubbles efficiently capture microplastic particles in the water, while the remaining PFAS in the water are adsorbed and enriched on the surface of the bubbles; Step 4: Droplet generation and aerosol capture; microbubbles carrying pollutants rise to the liquid interface and rupture; at the moment of bubble rupture, the cavity at its bottom collapses rapidly under the action of surface tension, generating an upward high-speed liquid jet; due to the high concentration of long-chain PFAS and microplastics at the interface, the concentration of pollutants in these droplets is much higher than that in the bulk solution; at this time, the relative humidity sensor probe (16) monitors the humidity change in the gas phase space; due to the large number of droplets ejected, the relative humidity of the gas phase space increases significantly, forming... A high-humidity aerosol environment is created; at the same time, the aerosol collection unit (28) is in operation; the negative pressure suction pump (33) forms a negative pressure zone in the conical gas collection hood (29) and quickly sucks in the droplets that have just been generated and ejected into the gas phase space; the droplets enter the cyclone separator (31) tangentially through the negative pressure resistant connecting hose (30); under the action of centrifugal force, the droplets separate from the airflow and slide down the wall to the pollutant collection bottle (32) at the bottom to form a high-concentration waste liquid, while the clean air is discharged from the top of the cyclone separator; Step 5: Intelligent feedback control; Throughout the entire operation of the device, the intelligent control cabinet (34) performs precise control based on sensor feedback: The temperature sensor probe (17) monitors the system temperature in real time. Once it detects that a drastic temperature fluctuation may change the viscosity and surface tension of the water, thereby affecting the bursting of bubbles, the PLC will immediately issue an alarm or link with external temperature control equipment for intervention; At the same time, the relative humidity sensor probe (16) is responsible for monitoring the stability of aerosol generation. If the relative humidity value is too low, that is, close to the ambient humidity, it indicates that the amount of droplets generated by the bursting of bubbles is insufficient or the airflow is too large. The PLC will instruct to increase the opening of the gas mass flow controller (26) to increase the bubble throughput; In the case of continuous RH saturation leading to a decrease in cyclone separation efficiency, the system will automatically optimize and adjust the pumping rate; This closed-loop feedback mechanism based on environmental parameters effectively ensures that the jet droplets are always generated and transported under the best physical conditions; Step 6: Water discharge and shutdown; After purification, the clean water enters the U-shaped adjustable overflow pipe (21) through the bottom outlet (20) and overflows into the external water collection tank under gravity to achieve continuous water discharge; After the treatment task is completed, the device shuts down according to the preset logic: First, the inlet peristaltic pump (3) and the gas supply control unit (24) are turned off, and after a delay of (30) seconds, the negative pressure suction pump (33) is turned off to ensure that the residual aerosol in the pipeline is completely emptied; Finally, the drain valve (22) at the bottom of the reactor body is opened to drain the remaining water in the reactor and complete one treatment cycle.

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