A device for photocatalytic degradation treatment of organic pollutants

Abstract

The application discloses a kind of photocatalytic degradation processing device for organic pollutants, it is related to wastewater treatment field, the device includes processing cylinder, inside center is equipped with the high-transparency quartz sleeve of built-in ultraviolet excitation light source, cyclone guide flow scraper is attached to the sleeve outer wall, two annular aeration distributors are equipped in processing cylinder from bottom to top;Processing cylinder bottom is equipped with single power driving source, through transmission structure simultaneously connect cyclone guide flow scraper and circulating reversing mechanism;Drive cyclone guide flow scraper rotation produces wall shear force and scrapes sleeve outer wall dirt, and induces downward cyclone;While through end face cam mechanism periodic mechanical trigger opening and closing component, control upper layer annular aeration distributor output intermittent pulse airflow, while lower layer keeps continuous aeration.The application not only can break catalyst electrostatic agglomeration, in-situ scale prevention, more through high-pressure pulse mass transfer and bubble-free light transmission synergies, realize photon transport and multiphase mass transfer space decoupling control, improve light excitation quantum efficiency.

Description

Technical Field

[0001] This invention relates to the technical field of wastewater treatment, specifically to a photocatalytic degradation device for organic pollutants. Background Technology

[0002] With the high-frequency detection of new pollutants such as hormones, antibiotics, and endocrine disruptors in water bodies, the development of efficient and green advanced treatment technologies has become an urgent need in the wastewater treatment field. Semiconductor photocatalytic degradation technologies (such as TiO2 and modified systems, g-C3N4 and modified systems, and bismuth (Bi)-based semiconductors) utilize light energy to excite and generate oxidizing holes (h+ VB) and reducing photoelectrons (e- CB), which react with H2O, O2, etc., to produce highly reactive free radicals (ROS), such as ·O2. － ·OH, h+ VB and 1 O2 and other active ROS indiscriminately attack the molecular chains of tetracyclines, sulfonamides, quinolones, etc., causing the C-C bonds, N-C bonds, etc. to break, and finally mineralize into harmless CO2, H2O and small molecule inorganic substances. It has the advantages of high efficiency, environmental protection and no secondary pollution.

[0003] However, traditional suspended photocatalytic reactors are constrained by the following three core bottlenecks in the process of industrial scale-up: (1) The problem of catalyst agglomeration and gravity sedimentation in multiphase systems is prominent. Nano or micron-sized photocatalyst particles (such as modified graphitic carbon nitride, bismuth-based semiconductors, etc.) are prone to electrostatic agglomeration in wastewater due to surface charge and van der Waals forces, resulting in a sharp drop in active specific surface area and caking sedimentation in the low shear zone of the reactor; (2) The antagonistic effect of photon transport and oxygen mass transfer is obvious. Photocatalytic reduction reaction urgently needs sufficient dissolved oxygen (DO) as an electron acceptor to suppress the rapid recombination of photogenerated electron-hole pairs (e-CB-h+VB). However, continuous strong aeration will produce a high-density gas-liquid interface, which will cause strong scattering and refraction of incident light (i.e., light blocking effect), resulting in an exponential decrease in the effective light penetration depth; if the aeration rate is reduced, local hypoxia will occur, and the quantum efficiency will drop sharply; (3) The dynamic scaling on the surface of the light-transmitting sleeve is serious. In the static boundary layer of water flow, catalyst particles and large molecular organic matter in wastewater are easily co-deposited on the outer wall of the quartz sleeve, forming a scale layer with strong light-shielding properties, which blocks the outward radiation of photons.

[0004] Existing technologies often employ discrete improvements such as adding external stirrers and PLC-controlled intermittent aeration. These not only significantly increase system energy consumption and control complexity but also fail to fundamentally address the synergistic issues of "flow field shearing, photon transport, and multiphase mass transfer" in the microscopic spatiotemporal dimension. Therefore, how to simultaneously solve the problems of "catalyst dispersion and mass transfer – eliminating bubble photoresistance" within a single reaction system has become a critical technological bottleneck that urgently needs to be overcome in this field. Summary of the Invention

[0005] Based on this, the purpose of this invention is to overcome the shortcomings of the prior art and provide a photocatalytic degradation treatment device for organic pollutants. This device, through its unique "continuous swirling shearing – continuous bottom aeration – mid-upper pulse oxygen supplementation," constructs a high-turbulence Taylor-Couette flow field inside the reactor, achieving spatiotemporal decoupling control of efficient photon transport (without bubble obstruction) and efficient multiphase mass transfer (high-concentration dissolved oxygen supply). This solves the common technical bottlenecks in existing technologies, such as photocatalyst agglomeration, bubble photoresistance effect, and casing fouling.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A photocatalytic degradation treatment device for organic pollutants includes a treatment cylinder with a protective shell installed at the bottom. A top plate is bolted to the center of the top of the treatment cylinder. A high-transparency quartz sleeve is suspended downward from the inner top of the treatment cylinder. Two ultraviolet excitation light sources are vertically and sequentially installed on the lower surface of the top plate via lamp holders. The two ultraviolet excitation light sources are inserted into the high-transparency quartz sleeve. A swirling guide scraper is provided on the outer wall of the high-transparency quartz sleeve. A driving assembly is provided inside the protective shell. The driving assembly is used to synchronously drive the swirling guide scraper to rotate to generate wall shear force to scrape off the dirt on the outer wall of the sleeve and agitate the wastewater in the cylinder to form a macroscopic swirling flow. The treatment cylinder has two annular aeration distributors arranged from bottom to top inside, connected by a vertical plate. An air supply pump is located on the outside of the treatment cylinder, connected to a first air inlet pipe and a second air inlet pipe. The first air inlet pipe connects to the lower annular aeration distributor, forming a continuous bubble plume at the bottom. The second air inlet pipe connects to an air storage tank and an air path control valve in sequence, then connects to the upper annular aeration distributor. A control box is also provided in the protective shell, and an opening and closing component electrically connected to the air path control valve is provided on one side of the control box. During rotation, the drive component periodically triggers the opening and closing component through mechanical linkage, intermittently controlling the air path control valve to open and close the air path of the upper annular aeration distributor, thereby forming an intermittent pulse bubble curtain in the upper part of the treatment cylinder.

[0007] Specifically, in this technical solution, a rotating shaft is sealed and inserted at the bottom center of the processing cylinder. A gap is left between the top end of the rotating shaft and the bottom end of the high-transparency quartz sleeve. A connecting plate is fixed to the outer wall of the rotating shaft inside the processing cylinder. One end of the connecting plate is fixedly connected to the bottom end of the swirling guide scraper. A wear-resistant silicone scraper is fixed to the inner edge of the swirling guide scraper that contacts the outer wall of the high-transparency quartz sleeve.

[0008] Specifically, the drive assembly includes a geared motor installed on the bottom wall of the protective housing. A drive gear is fixedly installed on the outer wall of the output end of the geared motor. A driven gear is fixedly installed on the outer wall of the rotating shaft inside the protective housing. The drive gear and the driven gear are meshed and connected. A small gear is fixedly fixed coaxially below the driven gear. The small gear is fixedly installed on the rotating shaft. A large gear meshes with the outside of the small gear. A vertical shaft is fixedly fixed at the center of the large gear. The vertical shaft is rotatably installed inside the protective housing.

[0009] Specifically, in this technical solution, an end face cam ring is fixed to the outer ring of the upper surface of the large gear, and the upper surface of the end face cam ring has a periodically undulating inclined transition area.

[0010] Specifically, the opening and closing assembly includes a vertically arranged moving rod. The top of the control box is bolted to the bottom wall of the processing cylinder. A base plate is installed at the bottom of the control box. The moving rod passes through the base plate and is in sliding contact with it. An abutment plate is fixed at the top of the moving rod. A limit switch is installed on the top of the side wall of the control box. The abutment plate is located below the limit switch.

[0011] Specifically, in this technical solution, a return spring is sleeved on the outer side of the moving rod, and the two ends of the return spring are respectively abutted against the lower surface of the abutment plate and the upper surface of the base plate. A ball is installed at the bottom end of the moving rod, and the ball maintains rolling contact with the upper surface of the end face cam ring on the large gear.

[0012] Specifically, in this technical solution, the limit switch is electrically connected to the pneumatic control valve via a wire, and the control box is equipped with a power supply module, which is electrically connected to the limit switch and the pneumatic control valve respectively.

[0013] Specifically, in this technical solution, several aeration nozzles are evenly arranged on the ring body of the two annular aeration distributors. Each aeration nozzle is provided with a three-dimensional porous shearing micro-medium mesh cover on its outer side. Each three-dimensional porous shearing micro-medium mesh cover is fixedly connected to the ring body of the annular aeration distributor. The lower annular aeration distributor is fixedly connected to the inner bottom wall of the treatment cylinder through a support rod.

[0014] Specifically, in this technical solution, the gas storage tank is provided with a pressure stabilizing buffer chamber, and a pressure sensor is installed inside the pressure stabilizing buffer chamber. The gas supply pump is connected to the pressure sensor for signal transmission.

[0015] Specifically, the upper and lower parts of the side wall of the processing cylinder are respectively connected to an inlet pipe and an outlet pipe. The outer ends of the inlet pipe and the outlet pipe are equipped with opening and closing valves. A suspended particulate semiconductor photocatalyst addition port is provided on one side of the top of the processing cylinder.

[0016] In summary, the present invention has the following main beneficial effects: 1. A Taylor-Couette shear flow field is constructed to break up photocatalyst agglomeration and achieve dead-zone-free suspension. A powerful radial and tangential shear flow is generated at the center of the reactor by driving a swirling guide scraper via a drive component. This, combined with the continuously rising bubble plume released upwards by the lower annular aeration distributor, creates a strong gas-liquid collision (Taylor vortex effect) in hydrodynamics. Three-dimensional chaotic mixing reshapes the hydrodynamic morphology, effectively eliminating low-velocity dead zones at the bottom and sides of the reactor, breaking down the electrostatic forces between suspended particulate semiconductor photocatalyst particles, and suspending them in a highly dispersed, monomeric state, maximizing the exposure of photocatalytic active sites.

[0017] 2. A spatiotemporal synergistic mechanism for pulsed oxygenation and light transmission gaps is constructed to solve the problem of light obstruction effect. This device breaks away from the traditional continuous aeration mode, utilizing a mechanical drive system to simultaneously control upper-layer pulsed aeration while performing scale scraping. During the pulse period when the gas path control valve is open, the instantaneous high-pressure airflow breaks the water film at the casing boundary, and the extremely high concentration of DO rapidly captures photogenerated e-CB, inhibiting the recombination of e-CB-h+ VB on the photocatalyst surface; during the gap period when the gas path control valve is closed, the dissipation of bubbles eliminates the scattering and refraction of ultraviolet light by the bubble curtain, achieving extremely low-loss deep penetration of light energy.

[0018] 3. In-situ dynamic scale prevention, maintaining constant photon excitation efficiency. This system uses a single geared motor power source and utilizes a mechanical transmission system to simultaneously complete in-situ dynamic physical cleaning (swirling guide scraper) and aeration logic control (end face cam triggered limit switch), eliminating the phenomenon of catalyst nucleation and scaling on the outer wall of the sleeve due to local temperature rise and electrostatic adsorption, ensuring constant excitation light intensity throughout the entire reaction operation life cycle.

[0019] 4. Highly integrated electromechanical-hydraulic passive mechanical self-synchronization ensures stable operation and low energy consumption. The air storage tank, in conjunction with a pressure sensor, forms a pneumatically pressure-stabilizing buffer chamber, ensuring the uniformity of instantaneous burst force and air volume for each pulse release. The entire system operates without complex electronic timing control systems intervening in the core mechanical actions, highly integrating physical blade scraping and scale prevention, flow field shear control, and pulse aeration frequency into a single rigid mechanical connection between the motor and cam. The faster the rotational speed, the more proportionally the scraping frequency and pulse frequency increase, achieving absolute self-adaptive synchronization through physical mechanisms. This avoids the problem of electrical components easily drifting and malfunctioning in the high humidity, corrosive, and strong radiation environments of wastewater treatment. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall isometric structure of the present invention; Figure 2 This is a cross-sectional isometric structural diagram of the processing cylinder of the present invention; Figure 3 This is a schematic diagram of the main cross-sectional structure of the processing cylinder of the present invention; Figure 4 This is a schematic diagram of the high-transparency quartz sleeve and ultraviolet excitation source structure of the present invention; Figure 5 This is a schematic diagram of the swirl guide scraper and drive assembly structure of the present invention; Figure 6 This is a schematic diagram of the end face cam ring and opening / closing assembly structure of the present invention; Figure 7 For the present invention Figure 6 Enlarged view of point A in the middle; Figure 8 This is a schematic diagram of the annular aeration distributor of the present invention.

[0021] Explanation of reference numerals in the attached drawings: 1. Processing cylinder; 101. Inlet pipe; 102. Drain pipe; 103. High-transparency quartz sleeve; 104. Annular aeration distributor; 1041. Aeration nozzle; 1042. Three-dimensional porous shear micro-media mesh cover; 1043. Vertical plate; 1044. Support rod; 2. Top plate; 201. Ultraviolet excitation light source; 202. Lamp holder; 3. Swirl guide scraper; 301. Connecting plate; 302. Rotating shaft; 4. Drive assembly; 401. Gear motor; 402. Active... 403. Driven gear; 404. Pinion; 405. Vertical shaft; 406. Large gear; 407. End face cam ring; 4071. Inclined surface; 5. Control box; 501. Base plate; 6. Opening and closing assembly; 601. Moving rod; 602. Ball bearing; 603. Abutment plate; 604. Return spring; 605. Limit switch; 7. Air supply pump; 701. First air inlet pipe; 702. Second air inlet pipe; 703. Air storage tank; 704. Air circuit control valve; 8. Protective housing. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0023] The embodiments of the present invention will now be described.

[0024] In this embodiment, please refer to Figure 1 - Figure 8 As shown, a photocatalytic degradation treatment device for organic pollutants includes a treatment cylinder 1, a protective shell 8 installed at the bottom of the treatment cylinder 1, an inlet pipe 101 and an outlet pipe 102 respectively connected to the upper and lower parts of the side wall of the treatment cylinder 1, and an opening and closing valve installed at the outer end of the inlet pipe 101 and the outlet pipe 102 to facilitate individual control of the water flow. A suspended particulate semiconductor photocatalyst addition port is provided on one side of the top of the treatment cylinder 1 to facilitate quantitative replenishment of suspended photocatalyst powder according to the wastewater concentration. A top plate 2 is bolted and sealed at the center of the top of the treatment cylinder 1. A rubber sealing gasket is fitted between the top plate 2 and the top end face of the treatment cylinder 1 to prevent leakage of wastewater and gas from the cylinder. A high-transparency quartz sleeve 103 is suspended downward from the inner top of the treatment cylinder 1. The high-transparency quartz sleeve 103 is made of high-transparency quartz material. Two ultraviolet excitation light sources 201 are vertically installed in sequence on the lower surface of the top plate 2 through lamp holders 202. The two ultraviolet excitation light sources 201 are inserted into the high-transparency quartz sleeve 103. 3. Made of quartz material with extremely low ultraviolet absorption rate, ensuring that ultraviolet radiation energy penetrates with very low loss, and that ultraviolet light fully irradiates the wastewater and catalyst inside the tube. A swirl guide scraper 3 is attached to the outer wall of the high-transparency quartz sleeve 103. A wear-resistant silicone pad is fixed to the outer wall of the swirl guide scraper 3 in contact with the outer wall of the high-transparency quartz sleeve 103. The silicone pad always maintains a tight fit with the outer wall of the high-transparency quartz sleeve 103 through interference fit. During the rotation process, the catalyst agglomerates and organic biofilm attached to the tube wall are peeled off by physical shear force. A rotating shaft 302 is sealed at the bottom center of the treatment cylinder 1. A rotary oil seal is installed between the rotating shaft 302 and the bottom wall of the treatment cylinder 1 to achieve dynamic sealing. A safety gap is left between the top of the rotating shaft 302 and the bottom of the high-transparency quartz sleeve 103. A connecting plate 301 is fixed to the outer wall of the rotating shaft 302 inside the treatment cylinder 1. One end of the connecting plate 301 is fixedly connected to the bottom of the swirl guide scraper 3. When the rotating shaft 302 rotates, it can synchronously drive the entire swirl guide scraper 3 to make a swirling spiral motion along the outer wall of the high-transparency quartz sleeve 103. On the one hand, the silicone pad continuously scrapes away the scale on the pipe wall to achieve in-situ dynamic scale prevention on the pipe wall. On the other hand, the spiral scraper blades do work on the fluid, creating a macroscopic spiral sinking flow field from top to bottom in the cylinder. This flow field merges with the aeration plume from bottom to top to form strong fluid shear and Taylor vortex, effectively breaking the electrostatic aggregation force between the suspended semiconductor photocatalyst particles, so that they are suspended in a highly dispersed single state. The protective housing 8 is equipped with a drive assembly 4. The drive assembly 4 is used not only to drive the swirling guide scraper 3, but also to serve as a mechanical trigger source for pulse aeration. The drive assembly 4 includes a geared motor 401 installed on the bottom wall of the protective housing 8. A drive gear 402 is fixedly installed on the outer wall of the output end of the geared motor 401. A driven gear 403 is fixedly installed on the outer wall of the rotating shaft 302 inside the protective housing 8. The drive gear 402 and the driven gear 403 are meshed and connected. Below the driven gear 403 is a small gear 404, which is fixedly mounted on the rotating shaft 302. A large gear 406 meshes with the outer side of the small gear 404. A vertical shaft 405 is fixed vertically at the center of the large gear 406. The vertical shaft 405 is rotatably mounted inside the protective housing 8. The large gear 406 can rotate smoothly independently with the vertical shaft 405. An end face cam ring 407 is fixed on the outer ring of the upper surface of the large gear 406. The end face cam ring 407 as a whole constitutes an end face cam mechanism. Its upper surface has an inclined surface 4071, and the high and low sections of the inclined surface 4071 have a smooth curved transition. The inside of the treatment cylinder 1 is provided with two annular aeration distributors 104 from bottom to top. The two annular aeration distributors 104 are rigidly connected by a vertical plate 1043. The lower annular aeration distributor 104 is fixedly connected to the inner bottom wall of the treatment cylinder 1 by a support rod 1044, so that the two sets of annular aeration distributors 104 are kept in a stable installation state of being coaxial and parallel. Several aeration nozzles 1041 are evenly provided on the ring body of the two annular aeration distributors 104. An air supply pump 7 is installed on the outside of the treatment cylinder 1. The air supply pump 7 is connected to an external oxygen source and is connected to a first air inlet pipe 701 and a second air inlet pipe 702. The first air inlet pipe 701 passes through the wall of the treatment cylinder 1 and connects to the lower annular aeration distributor 104, which provides continuous and steady-state aeration throughout the process. The second air inlet pipe 702 is connected to the air storage tank 703 and the air path control valve 704 in sequence, and then connects to the upper annular aeration distributor 104. The air storage tank 703 has a pressure stabilizing buffer chamber inside, and a pressure sensor is installed inside the pressure stabilizing buffer chamber. The air supply pump 7 is connected to the pressure sensor signal. When the air pressure inside the air storage tank 703 is lower than the set threshold, the air supply pump 7 automatically increases the air supply power to store pressure, ensuring that the upper aeration nozzle 1041 can output a pulse airflow with high initial kinetic energy every time the air path control valve 704 is opened. The protective housing 8 is also equipped with a control box 5. The top flange of the control box 5 is fixed to the lower surface of the bottom wall of the treatment cylinder 1 by sealing bolts. On one side of the control box 5, there is an opening and closing component 6 electrically connected to the air circuit control valve 704. When the drive component 4 rotates, it periodically triggers the opening and closing component 6 through mechanical contouring motion, thereby intermittently opening the air circuit control valve 704 and realizing intermittent pulse aeration of the upper annular aeration distributor 104.

[0025] Before starting the equipment, the operator adds a quantitative amount of suspended granular semiconductor photocatalyst into the treatment cylinder 1 through the catalyst addition port, closes the sealing cover of the addition port, opens the inlet pipe 101 valve, and transports the organic pollutant wastewater to be treated into the treatment cylinder 1. After the wastewater level completely covers the high-transparency quartz sleeve 103 and the two sets of annular aeration distributors 104, the inlet valve is closed to complete the water intake process. Then, the main power supply of the device is turned on, and the two ultraviolet excitation light sources 201 are lit synchronously. The ultraviolet light penetrates the high-transparency quartz sleeve 103 to irradiate the wastewater in the cylinder, providing light conditions for the photocatalytic degradation reaction. The air supply pump 7 and the geared motor 401 are started simultaneously to enter the collaborative operation state. Steady-state fluidization and basic reaction stage: After the air supply pump 7 starts, the external oxygen source is delivered in two ways: one way is through the first air inlet pipe 701 to the lower annular aeration distributor 104, and the lower aeration nozzle 1041 continuously sprays a continuous stream of microbubbles into the water, guiding the fluid at the bottom to move upward, providing basic DO for the entire system; at the same time, the geared motor 401, after being reduced in speed and increased in torque by the gear system (driving gear 402, driven gear 403), drives the swirling guide scraper 3 to rotate at low speed. When it sweeps the fluid, it generates strong tangential and radial shear forces, forcing the water to generate a spiral downward flow in the annular space of the cylindrical treatment cylinder 1. The upward continuous bubble plume and the downward spiral flow converge and collide in the lower part of the reactor, and the shear force instantaneously induces strong Taylor-Couette vortices in the local fluid. The high-frequency turbulent shear force generated by the vortex is much greater than the electrostatic attraction and van der Waals forces between photocatalyst particles, which forcibly tears and disperses the highly polar nanocatalyst particle agglomerates, and they are suspended in a single state without dead angles, thus solving the problem of agglomeration and sedimentation in the bottom edge area of ​​traditional reactors. Another oxygen supply is introduced into the pressure-stabilizing buffer chamber of the gas storage tank 703 through the second air inlet pipe 702 for storage. The gas pressure sensor in the gas storage tank 703 monitors the gas pressure in the chamber in real time. When the gas pressure is insufficient, it automatically adjusts the output power of the air supply pump 7. Under normal conditions, the gas path control valve 704 is kept de-energized and closed, and the gas path between the gas storage tank 703 and the upper annular aeration distributor 104 is disconnected, so there is no aeration airflow output from the upper layer. In-situ scraping and pulse oxygenation and light transmission synergistic stage (core feature): The geared motor 401 outputs power to drive the active gear 402 to rotate. The active gear 402 drives the meshing driven gear 403 and the rotating shaft 302 to rotate synchronously. The rotating shaft 302 drives the connecting plate 301 to rotate synchronously, which in turn drives the swirling guide scraper 3 to rotate spirally along the outer wall of the high-transparency quartz sleeve 103. The wear-resistant silicone pad on the inner side of the scraper makes a wall-adhering spiral motion, performing in-situ, slightly interference mechanical scraping on the outer wall of the high-transparency quartz sleeve 103, completely eliminating the static boundary layer, blocking the nucleation and growth process of the scale layer, ensuring that ultraviolet excited photons can be transmitted into the fluid without obstruction, maintaining long-term high excitation efficiency. During the rotation of the swirling guide scraper 3, the water in the agitator is stirred to form a spiral downward swirling flow. The swirling flow drives the water and suspended particulate semiconductor photocatalyst to mix fully, improving the uniformity of contact between ultraviolet light and pollutants and catalysts. At the same time, the rotating shaft 302 will also drive the pinion 404 to rotate synchronously. The pinion 404 drives the meshing large gear 406 and the vertical shaft 405 to rotate. The end face cam ring 407 on the upper surface of the large gear 406 and the swirling guide scraper 3 rotate synchronously at the same speed. When the end face cam ring 407 continues to rotate, the ball 602 at the bottom of the opening and closing component 6 always rolls against the upper surface of the end face cam ring 407. When the inclined surface 4071 of the end face cam ring 407 is in a low position When the area rotates to below the ball bearing 602, the air control valve 704 remains de-energized and closed, and the upper annular aeration distributor 104 stops aeration. When the high section of the inclined surface 4071 of the end face cam ring 407 rotates to below the ball bearing 602, the air control valve 704 is opened, and the high-pressure oxygen stored inside the air storage tank 703 is instantly introduced into the upper annular aeration distributor 104, and pulse airflow is sprayed outward from the upper aeration nozzle 1041 to complete one intermittent aeration action. The airflow ejected from the aeration nozzle 1041 surges upward at high speed, instantly tearing apart the static water film on the outside of the high-transparency quartz sleeve 103. This prevents pollutants gradually accumulating in the boundary water film from blocking the transmission of ultraviolet light. The pulsed airflow can also further promote the catalyst particles to be evenly dispersed around the high-transparency quartz sleeve 103, allowing organic pollutants to more fully contact and react with the active sites on the catalyst surface. After each pulse aeration, the lower section of the inclined plane 4071 rotates again to below the ball bearing 602, the gas path control valve 704 is disconnected again, and the gas storage tank 703 accumulates oxygen again to wait for the next pulse aeration. This cycle is repeated periodically to achieve stable intermittent pulse aeration. After the degradation treatment is completed, the ultraviolet excitation light source 201, the air supply pump 7, and the reduction motor 401 are turned off. After standing for a while, the valve of the drain pipe 102 is opened to discharge the treated wastewater that meets the standards, thus completing one photocatalytic degradation treatment of organic pollutants. This avoids catalyst settling and accumulating in the low-speed area at the bottom of the cylinder, as well as electrostatic agglomeration and caking, ensuring that catalyst particles are fully dispersed to expose all active sites. It also enables intermittent pulse aeration, with the airflow continuously breaking through the static boundary water film on the outer wall of the high-permeability quartz sleeve 103 that blocks light and mass transfer, ensuring that ultraviolet light can stably penetrate and excite the catalyst to generate active ROS. This effectively overcomes the technical defects of existing single-bottom aeration systems, such as catalyst agglomeration and deactivation, poor interfacial mass transfer, and low degradation efficiency.

[0026] Please see Figure 6 and Figure 7 As shown, the opening and closing assembly 6 includes a vertically arranged moving rod 601. The top of the control box 5 is bolted to the bottom wall of the processing cylinder 1. A base plate 501 is installed at the bottom of the control box 5. The moving rod 601 passes through the base plate 501 and is in sliding contact. An abutment plate 603 is fixed to the top of the moving rod 601. A limit switch 605 is installed on the top of the side wall of the control box 5. The abutment plate 603 is located below the limit switch 605. A return spring 604 is sleeved on the outer side of the moving rod 601. The two ends of 04 are fixedly connected to the lower surface of the abutment plate 603 and the upper surface of the base plate 501, respectively. A ball bearing 602 is installed at the bottom end of the moving rod 601. The ball bearing 602 rolls in contact with the inclined surface 4071 at the top of the end face cam ring 407 in the drive assembly 4. The limit switch 605 is electrically connected to the pneumatic control valve 704 through a wire. The control box 5 is equipped with a power supply module, which is electrically connected to the limit switch 605 and the pneumatic control valve 704 to provide a stable working power supply.

[0027] As the end face cam ring 407 continues to rotate, the ball bearing 602 at the bottom of the opening and closing assembly 6 always rolls and conforms to the upper surface of the end face cam ring 407: When the high section of the inclined surface 4071 of the end face cam ring 407 rotates to below the ball 602, the inclined surface 4071 pushes the ball 602 upward, the moving rod 601 slides upward as a whole, the return spring 604 is stretched, and the abutment plate 603 at the top of the moving rod 601 touches the limit switch 605 upward. The limit switch 605 outputs an electrical signal to instantly open the gas control valve 704. This high-energy pulsed airflow instantly tears apart the static boundary water film on the outside of the high-transparency quartz sleeve 103 that hinders mass transfer, causing the wastewater and catalyst to mix violently. More importantly, the large amount of oxygen pulsed in rapidly increases the instantaneous DO concentration in the upper layer of the system. As a strong electron acceptor, oxygen greatly inhibits the recombination of photogenerated e- CB- h+ VB on the surface of the suspended particulate semiconductor photocatalyst, and instantaneously excites a large amount of O2. － ·OH and 1 O2 significantly increases the instantaneous mineralization rate; When the lower region of the inclined surface 4071 of the end face cam ring 407 rotates to below the ball 602, the ball 602 presses down on the moving rod 601 under its own weight, the return spring 604 extends synchronously, and the abutment plate 603 at the top of the moving rod 601 moves downward away from the sensing area of ​​the limit switch 605. The limit switch 605 has no trigger signal output, the gas control valve 704 is de-energized and closed, and aeration stops. The high-pressure bubbles in the upper and middle regions escape rapidly upward under the action of buoyancy and completely dissipate in a very short time. At this time, the fluid in the upper part of the reactor enters the "zero gas phase light transmission window period". Since the strong scattering and refraction of light by the bubble curtain is eliminated (the light resistance effect is reduced to zero), the photons emitted by the ultraviolet tube can enter the oxygen-rich and highly dispersed fluid system with maximum optical penetration depth and extremely low loss, deeply exciting the far-end photocatalyst particles and saturating their photoexcitation state. This device achieves perfect decoupling of photoexcitation and oxygen mass transfer on the time axis through a mechanically synchronized design of "pulse aeration" and "rotational shearing" using a single power source. The faster the rotation speed, the higher the pulse frequency automatically and proportionally increases, always maintaining a dynamic balance between fluid dynamics and photochemical reaction rates.

[0028] Please see Figure 8 As shown, each aeration nozzle 1041 is equipped with a three-dimensional porous shear micro-medium mesh 1042 on its outer side. Each three-dimensional porous shear micro-medium mesh 1042 is fixedly connected to the ring body of the annular aeration distributor 104. The mesh diameter of the three-dimensional porous shear micro-medium mesh 1042 is in the micrometer range. When a pulsed high-pressure airflow or a continuous bottom airflow passes through the three-dimensional porous shear micro-medium mesh 1042, larger bubbles are forcibly cut and refined into micrometer-sized bubbles. Micro- and nano-bubbles have the hydrodynamic characteristics of large specific surface area, high internal pressure, and long residence time in water. They not only multiply the gas-liquid mass transfer efficiency of oxygen, but the micro-jet released at the moment of rupture can also simultaneously clean the surface of the three-dimensional porous shear micro-medium mesh 1042 and the high-transparency quartz sleeve 103. In this embodiment, the three-dimensional porous shearing micro-medium mesh cover 1042 not only plays a role in multi-stage bubble cutting when pulsed high-pressure gas passes through, greatly increasing the gas-liquid contact area; its more important physical function is that during the "gap period" when the gas path control valve 704 is closed, the three-dimensional porous shearing micro-medium mesh cover 1042 relies on the liquid damping and surface tension of the microporous medium to form a physical anti-siphon barrier, completely preventing the micro-nano catalyst particles suspended in the reactor from being reverse-drawn into the upper annular aeration distributor 104, effectively avoiding the periodic blockage of the aeration nozzle 1041, and realizing the maintenance-free and stable operation of the device.

[0029] The working principle of this invention is as follows: After the main power is switched on, the ultraviolet excitation source 201 is simultaneously lit, and high-frequency ultraviolet photons penetrate the high-transparency quartz sleeve 103 and radiate outward, constructing a uniformly distributed isotropic excitation light field within the processing cylinder 1. Simultaneously, the air supply pump 7 and the geared motor 401 are started, and the system automatically enters a three-dimensional chaotic collaborative operation state of "flow field reshaping – in-situ scale prevention – spatiotemporal decoupling of multiphase mass transfer and photon transport" through passive mechanical rigid linkage. Its microscopic and macroscopic physicochemical reaction processes are divided into the following three stages: Phase 1: Bottom-level steady-state fluidization and macroscopic Taylor vortex reshaping. After the air supply pump 7 starts, the first stream of oxygen enters the lower-level annular aeration distributor 104 through the first air inlet pipe 701, continuously releasing microbubbles to the bottom of the cylinder. The continuous rising bubble plume not only provides the O2 concentration needed to maintain the baseline of photocatalytic reaction throughout the water body, but also ensures basic active ROS, such as O2. － ·OH, h+ VB and 1 The continuous generation of O2 and other substances mineralizes organic pollutants. Furthermore, the upward-moving bubbles exert a continuous upward fluid drag force on the suspended particulate semiconductor photocatalyst, preventing its tendency to settle due to gravity. Synchronously, the geared motor 401, after being reduced in speed by a gear set, drives the rotating shaft 302, causing the swirling guide scraper 3 to rotate at low speed along the outer wall of the sleeve. The wear-resistant silicone pad on the inner side of the scraper is physically swept tangentially to peel off and remove the micro-nano catalyst deposits and organic biofilms attached to the outer wall of the high-transmittance quartz sleeve 103 in situ, maintaining its near 100% ultimate light transmittance. When the scraper blades rotate, they do work on the fluid, inducing a macroscopic spiral downward flow. This downward swirling flow and the continuous upward rising bubble group at the bottom of the tube undergo intense shearing and convection collisions, generating a highly turbulent Taylor-Couette chaotic flow field in the low-speed zone at the bottom and edge of the tube. The local high shear stress generated by this chaotic flow field instantly overcomes the electrostatic double-layer attraction and van der Waals forces between semiconductor particles, achieving efficient deagglomeration of the catalyst and making it uniformly fluidized and suspended in a highly dispersed monomer state.

[0030] The second stage: High-pressure pulse oxygenation triggered by mechanical linkage. The second stream of oxygen is forced into the pressure-stabilizing buffer chamber of the gas storage tank 703 for energy storage and pressurization. While the rotating shaft 302 drives the scraper, it also rotates synchronously with the end face cam ring 407 via a gear pair (small gear 404, large gear 406) at a predetermined reduction ratio. When the high section of the inclined surface 4071 of the end face cam ring 407 rotates below the ball bearing 602 of the opening / closing assembly 6, the cam mechanism converts the rotational motion into a vertically upward mechanical displacement, pushing the motion rod 601 and triggering the limit switch 605, instantly opening the gas path control valve 704. At this time, the high-pressure oxygen accumulated in the gas storage tank 703 is instantly ejected with extremely high transient jet kinetic energy through the nozzle of the upper annular aeration distributor 104, forming a high-energy pulsed bubble curtain in the upper part of the reactor (photo-excitation core area). This transient high-energy aeration produces the following microscopic reaction enhancement mechanism: Air circuit control valve 704 controls the upper aeration distributor; The intense pulsed airflow instantly tears apart the static boundary water film on the outside of the high-transparency quartz sleeve 103, which hinders mass transfer. This causes a violent collision between high-concentration organic molecules and highly fluidized photocatalyst particles in the extremely high light intensity region on the outer wall of the sleeve, breaking the mass transfer limit. The pulsed injection of saturated high-concentration DO acts as an extremely strong electron acceptor, capturing photogenerated e-CB on the surface of the suspended particulate semiconductor photocatalyst at an extremely high rate at the micro-interface. This fundamentally inhibits the rapid recombination of e-CB-h+ VB pairs, causing the residual h+ VB and ROS on the valence band to be generated explosively at this instant, bringing the degradation reaction rate to its peak.

[0031] The third stage: the bubble dissipation and high-energy photon transport window. When the lower section of the inclined surface 4071 of the end face cam ring 407 rotates to below the ball bearing 602, the gas path control valve 704 resets and closes, the upper layer pulse aeration stops abruptly, and the gas storage tank 703 re-enters the energy storage state. At this time, the upper water body enters a valuable "light transmission gap period": the dense bubble group in the upper layer quickly dissipates, eliminating the severe scattering and refraction of ultraviolet light by the bubble curtain (eliminating the light resistance effect). During this window period, the high-energy ultraviolet photons emitted by the high-transmittance quartz sleeve 103 are lased onto the photocatalyst particles that have just completed oxygen-enriched mixing and are in a highly dispersed state with maximum penetration depth and extremely low loss. In the pure liquid phase system without bubble interference, the catalyst is deeply excited to the saturated excited state, and the quantum yield achieves a leapfrog improvement.

[0032] Under the pure mechanical autonomous control of the geared motor 401, the above-mentioned "high-pressure pulse enhanced mass transfer" and "bubble dissipation enhanced light transmission" form a highly precise spatiotemporal periodic cycle. After the degradation treatment meets the standards, each electrical component is turned off in sequence. After standing for a while, the valve of the drain pipe 102 is opened to discharge the clean water, thus completing the photocatalytic deep treatment of a batch of organic polluted wastewater.

[0033] Although embodiments of the present invention have been shown and described, these specific embodiments are merely explanations of the invention and are not intended to limit it. The specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. After reading this specification, those skilled in the art may make modifications, substitutions, and variations to the embodiments as needed without departing from the principles and spirit of the invention, but such modifications, substitutions, and variations are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A photocatalytic degradation treatment device for organic pollutants, comprising a treatment cylinder (1), characterized in that: The treatment cylinder (1) is sealed at the top center with a high-transparency quartz sleeve (103) extending into the cylinder. At least one ultraviolet excitation light source (201) is installed inside the high-transparency quartz sleeve (103). A swirling flow guide scraper (3) that can rotate around its axis is attached to the outer wall of the high-transparency quartz sleeve (103). The treatment cylinder (1) is provided with a lower annular aeration distributor (104) and an upper annular aeration distributor (104) from bottom to top. The processing cylinder (1) is equipped with an air supply pump (7) on its exterior. The air supply pump (7) is divided into two air supply paths. The first path is connected to the first air inlet pipe (701) and connected to the lower annular aeration distributor (104) to provide continuous aeration. The second path is connected to the second air inlet pipe (702) and connected to the upper annular aeration distributor (104) via the air path control valve (704). The bottom of the treatment cylinder (1) is provided with a drive assembly (4), which is a single power source. Its output end is connected to and drives the swirling guide scraper (3) through a transmission structure, so that it rotates around the high-transparency quartz sleeve (103) to scrape off the deposits on the tube wall and generate a downward swirling flow. The bottom of the treatment cylinder (1) is provided with an opening and closing assembly (6). During the rotation, the drive assembly (4) periodically triggers the opening and closing assembly (6) through the mechanical cam contour motion, intermittently opening the air path control valve (704) so ​​that the upper annular aeration distributor (104) outputs intermittent pulse airflow.

2. The photocatalytic degradation device for organic pollutants according to claim 1, characterized in that, A rotating shaft (302) is sealed at the bottom center of the processing cylinder (1). A gap is left between the top end of the rotating shaft (302) and the bottom end of the high-transparency quartz sleeve (103). A connecting plate (301) is fixed on the outer wall of the rotating shaft (302) inside the processing cylinder (1). One end of the connecting plate (301) is fixedly connected to the bottom end of the swirling flow guide scraper (3). A wear-resistant silicone pad is fixed on the inner edge of the swirling flow guide scraper (3) that contacts the outer wall of the high-transparency quartz sleeve (103).

3. The photocatalytic degradation device for organic pollutants according to claim 2, characterized in that, The drive assembly (4) includes a geared motor (401), the output shaft of which is fixed with a drive gear (402); the bottom end of the rotating shaft (302) is fixed with a driven gear (403) and a coaxial pinion (404), the drive gear (402) meshing with the driven gear (403); the drive assembly (4) also includes a vertical shaft (405) and a large gear (406) fixed on the vertical shaft (405), the pinion (404) meshing with the large gear (406), the upper surface of the large gear (406) is fixed with an end face cam ring (407), the upper surface of the end face cam ring (407) is provided with a periodically undulating inclined surface (4071).

4. The photocatalytic degradation device for organic pollutants according to claim 3, characterized in that, The opening and closing assembly (6) includes a limit switch (605) installed on the top of the control box (5) and a moving rod (601) vertically inserted on the bottom plate (501) of the control box (5); the top of the moving rod (601) is fixed with an abutment plate (603) located directly below the limit switch (605), and the bottom is equipped with a ball (602) that rolls in contact with the upper surface of the end face cam ring (407); a return spring (604) is sleeved on the outside of the moving rod (601).

5. The photocatalytic degradation device for organic pollutants according to claim 1, characterized in that, The second air inlet pipe (702) has an air storage tank (703) connected in series on the pipeline between the air supply pump (7) and the air circuit control valve (704). The air storage tank (703) forms a pressure stabilizing buffer chamber inside, and a pressure sensor connected to the air supply pump (7) is installed inside the pressure stabilizing buffer chamber.

6. The photocatalytic degradation device for organic pollutants according to claim 1, characterized in that, The two annular aeration distributors (104) are rigidly connected by a vertical plate (1043), and the lower annular aeration distributor (104) is fixedly connected to the inner bottom wall of the treatment cylinder (1) by a support rod (1044).

7. A photocatalytic degradation device for organic pollutants according to claim 1 or 6, characterized in that, The annular aeration distributor (104) has a number of aeration nozzles (1041) evenly arranged on its ring body. Each aeration nozzle (1041) is covered with a three-dimensional porous shearing micro-medium mesh cover (1042) fixedly connected to the ring body. The three-dimensional porous shearing micro-medium mesh cover (1042) has micron-level micropores, which are used to perform multi-stage shearing and refinement of the jet fluid, and serve as a physical barrier to prevent the suspended photocatalyst particles in the treatment cylinder (1) from being drawn back into the aeration distributor pipeline.

8. The photocatalytic degradation device for organic pollutants according to claim 1, characterized in that, The upper and lower parts of the side wall of the processing cylinder (1) are respectively connected to an inlet pipe (101) and a drain pipe (102) equipped with opening and closing valves. The top side of the processing cylinder (1) is provided with a suspended particulate semiconductor photocatalyst addition port.

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