Microporous aeration electrode, gas-liquid mixed-phase discharge device and fluid treatment method

Abstract

The invention discloses a microporous aeration electrode, a gas-liquid mixed-phase discharge device and a fluid treatment method. The microporous aeration electrode comprises a central electrode, an outer electrode and an insulating supporting piece for fixing the central electrode and the outer electrode, the central electrode is of a hollow structure with an air inlet, an inner cavity of the central electrode can be used as an air distribution channel, a plurality of through micropores are formed in the side wall of the central electrode, the outer electrode is of a flow-through conductive structure, and the insulating supporting piece is used for fixing the central electrode and the outer electrode. The outer electrode is provided with a grounding end, the outer electrode is arranged on the outer side of the central electrode, and a discharge reaction area is formed between the central electrode and the outer electrode. The novel coaxial gas-liquid mixed-phase discharge reactor is simple in structure, can realize gas distribution-discharge integrated coupling, breaks through short-life particle transmission limitation, has an electrode self-protection function, and meets the high-efficiency requirement of industrial continuous flow treatment.

Description

Technical Field

[0001] This invention relates to the field of low-temperature plasma application technology, specifically to a microporous aeration electrode, a gas-liquid mixed-phase discharge device, and a fluid treatment method. Background Technology

[0002] Low-temperature plasma technology, as an advanced oxidation and process intensification technology integrating high-energy electrons, strong oxidizing free radicals such as hydroxyl radicals and oxygen radicals, excited-state molecules, and ultraviolet radiation, has shown great application potential in fields such as environmental pollution control, fine chemical synthesis, biomedical sterilization, and nanomaterial preparation. Its core advantage lies in its ability to induce high-energy chemical reactions under mild macroscopic reaction conditions in a non-equilibrium state, achieving material transformation processes that are difficult to achieve using conventional methods. However, applying plasma technology to liquid-phase systems faces significant physical limitations. Traditional direct liquid-phase discharge modes must overcome the extremely high dielectric strength of the liquid medium, thus typically requiring extremely high breakdown voltages. This not only leads to high power supply equipment costs and low energy utilization but also often results in strong Joule heating, easily causing the liquid medium to boil or thermally degenerate, rather than producing the expected chemical effects. To reduce breakdown voltage and improve energy efficiency, introducing a gaseous medium to construct a gas-liquid mixed-phase discharge system has become the current mainstream technical approach. By introducing bubbles into the liquid phase and utilizing the relatively low dielectric strength inside the bubbles as a "weak point" to induce discharge, energy consumption can be significantly reduced. However, existing gas-liquid mixed-phase discharge reactors, especially those using independent aeration devices, still face insurmountable technical bottlenecks in practical engineering applications.

[0003] Existing devices typically employ a structure where the bottom microporous aerator head and the upper-middle electrodes are physically separated. This means that the active particles generated by the discharge must undergo a process of "gas-phase generation - diffusion transport - gas-liquid interface adsorption." Due to the extremely short lifespan of core active species such as hydroxyl radicals, most high-energy particles quench before reaching the liquid interface, resulting in only the longer-lived ozone participating in the reaction, significantly limiting the reaction rate and treatment depth. Simultaneously, traditional aeration methods produce large and unevenly distributed bubbles, resulting in a limited gas-liquid contact surface area. Furthermore, ordinary bubbles tend to coalesce in liquids, further reducing the gas-liquid mass transfer coefficient, making it difficult for active substances in the gas phase to quickly dissolve into the liquid phase and participate in the reaction. Additionally, in traditional structures, the metal electrodes are directly exposed to a corrosive gas-liquid environment and lack an effective in-situ cooling mechanism; the heat accumulated from long-term high-voltage discharge easily leads to electrode thermal corrosion. Moreover, when treating wastewater containing salt or suspended solids, mineral scaling or contaminant deposition easily occurs on the electrode surface, leading to discharge performance degradation or even short circuits, severely affecting the continuous operational stability of the equipment. Summary of the Invention

[0004] This invention addresses the aforementioned problems by researching and designing a microporous aeration electrode, a gas-liquid mixed-phase discharge device, and a fluid treatment method. The technical means employed in this invention are as follows: A microporous aeration electrode includes a central electrode, an outer electrode, and an insulating support for fixing the central electrode and the outer electrode. The central electrode is a hollow structure with an air inlet, and its inner cavity can serve as an air distribution channel. The sidewall of the central electrode is provided with several through micropores. The outer electrode is a permeable and conductive structure and is provided with a grounding terminal. The outer electrode is located outside the central electrode, forming a discharge reaction zone between the central electrode and the outer electrode. Furthermore, the central electrode is a hollow tubular structure, the outer electrode is a cylindrical or plate-like structure sleeved on the outside of the central electrode, the insulating support is fixed at both ends of the outer electrode, and the central electrode extends through the insulating support to form a gas inlet.

[0005] Furthermore, the central electrode is a metal tube or a tubular structure made of porous material with through holes on the sidewall, the diameter of the through micropore is 10 μm to 1000 μm, and the central electrode and the outer electrode are coaxially arranged.

[0006] Furthermore, the central electrode is a porous metal sintered tube, a laser-drilled metal tube, or a porous ceramic tube with a conductive coating on its surface. The outer electrode is made of stainless steel wire mesh or a porous metal perforated plate. The insulating support includes an upper end cover and a lower end cover. The inner surfaces of the upper end cover and the lower end cover are provided with annular positioning grooves for embedding and fixing the outer electrode. The two ends of the central electrode pass through the upper end cover and the lower end cover respectively, and are sealed to the upper end cover and the lower end cover by fasteners.

[0007] Furthermore, a dielectric barrier structure may be provided between the central electrode and the outer electrode.

[0008] Furthermore, the dielectric barrier structure includes an inner barrier layer disposed on the outer sidewall of the central electrode, or an outer barrier layer disposed on the inner sidewall of the outer electrode, or a dual dielectric barrier layer in which both an inner barrier layer and an outer barrier layer exist; when the dielectric barrier structure includes an inner barrier layer, a connecting vent is provided on the inner barrier layer at the position corresponding to the through-hole of the central electrode, so as to ensure that the gas can be ejected normally.

[0009] Furthermore, the dielectric barrier structure may also be a solid insulating separator disposed between the central electrode and the outer electrode; the material of the solid insulating separator is selected from one or more of ceramic, quartz, glass, polytetrafluoroethylene or composite insulating materials; the structural form of the solid insulating separator is a porous tube, a sintered mesh tube or a fiber diaphragm.

[0010] A gas-liquid mixed-phase discharge device includes the microporous aeration electrode described in this invention, and also includes a housing, wherein the microporous aeration electrode is disposed inside the housing, and the housing is provided with an inlet and an outlet.

[0011] Furthermore, the outer shell has a cylindrical structure, and the water inlet is arranged along the tangential direction of the outer shell.

[0012] A fluid treatment method using the microporous aeration electrode or gas-liquid mixed-phase discharge device described in this invention.

[0013] Compared with the prior art, the beneficial effects of the present invention are: (1) The integrated coupling of micropore gas distribution and high-voltage discharge is realized, significantly reducing process energy consumption. This invention utilizes the conductive micropores on the wall of the central electrode tube for direct gas distribution. Based on the "micropore edge electric field enhancement effect", the electric field is highly confined at the micropore outlet; combined with the low dielectric constant characteristics of the newly generated microbubble interior and gas-liquid interface, the bubble can be broken down at a voltage far lower than that of traditional reactors, inducing high-density micro-discharge. This low-voltage, high-density discharge mode significantly improves energy yield and reduces energy consumption per unit of fluid processed.

[0014] (2) Overcoming transmission limitations to achieve in-situ reaction at "zero distance at the gas-liquid interface". This device precisely locks the discharge region at the instant of bubble generation and at its gas-liquid interface. The generated high-energy electrons and short-lived free radicals do not need to undergo gas phase transport and can directly act on the substrate at the gas-liquid interface within the nanosecond time of generation. This "in-situ generation and in-situ reaction" mechanism has a decisive efficiency advantage for processes such as free radical-dominated chemical synthesis, conversion of recalcitrant substances, and rapid sterilization.

[0015] (3) The dual protection mechanism of "air cooling-self-cleaning" solves the problems of thermal corrosion and scaling. The working gas is continuously ejected from the inside of the central electrode through the micropores. The airflow directly carries away the Joule heat generated in the core discharge area, realizing the "self-cooling" of the electrode and avoiding local high temperature damage to the heat-sensitive liquid phase medium and electrode thermal corrosion. On the other hand, the continuous outward airflow forms a "gas phase barrier" at the micropore outlet, which can continuously blow and wash the electrode surface. This "self-cleaning" effect effectively prevents minerals, reaction by-products or suspended particles in the liquid phase from depositing and scaling at the electrode micropores, fundamentally eliminating discharge short circuits or performance degradation caused by electrode contamination, and ensuring long-term stable operation of the device under complex working conditions. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the axial cross-sectional structure of Embodiment 1 and Embodiment 2 of the present invention.

[0017] Figure 2 This is a schematic diagram of the axial cross-sectional structure of Embodiment 3 of the present invention.

[0018] Figure 3 This is a schematic diagram of the implementation state of the microporous aeration electrode described in Embodiment 1 of the present invention.

[0019] Figure 4 This is a schematic diagram of the axial cross-sectional structure of Embodiment 10 of the present invention. Detailed Implementation

[0020] like Figure 1 As shown, a microporous aeration electrode includes a central electrode 1, an outer electrode 2, and an insulating support 3 for fixing the central electrode 1 and the outer electrode 2. The central electrode 1 is a hollow structure with an air inlet 6, and its inner cavity serves as an air distribution channel. The sidewall of the central electrode 1 has several through-holes 7. The outer electrode 2 is a permeable and conductive structure and has a grounding terminal. The outer electrode 2 is located outside the central electrode 1, forming a discharge reaction zone 4 between the central electrode 1 and the outer electrode 2. The central electrode has a high-voltage power supply connection terminal, and the outer electrode has a grounding terminal.

[0021] The central electrode 1 is a hollow tubular structure, and the outer electrode 2 is a cylindrical or plate-like structure sleeved on the outside of the central electrode. An annular discharge reaction zone 4 is formed between the central electrode 1 and the outer electrode 2 to accommodate the fluid to be treated and the microbubbles 5 ejected from the through-holes 7. The insulating support 3 is fixed to both ends of the outer electrode 2, and the central electrode 1 extends through the insulating support 3 to form an air inlet 6.

[0022] The central electrode 1 is a tubular structure made of metal tube or porous material with through holes on the side wall. The diameter of the through micropore 7 is 10 μm to 1000 μm. The central electrode 1 and the outer electrode 2 are coaxially arranged.

[0023] The central electrode 1 is a porous sintered metal tube, a laser-drilled metal tube, or a porous ceramic tube with a conductive coating on its surface. The outer electrode 2 is made of stainless steel wire mesh or a porous perforated metal plate. The mesh size or pore diameter of the outer electrode 2 is selected according to the viscosity of the fluid to be treated and the size of the suspended particles.

[0024] In this embodiment, the insulating support 3 includes an upper end cap and a lower end cap respectively disposed at both ends of the microporous aeration electrode. The inner surfaces of the upper and lower end caps are provided with annular positioning grooves for embedding and fixing the outer electrode. The two ends of the central electrode 1 pass through the central holes of the upper and lower end caps respectively, and are sealed to the upper and lower end caps by fasteners. The two ends of the central electrode 1 are provided with external threads, and the fastener is a locking nut 8. A sealing washer 9 is also provided between the locking nut 8 and the insulating support 3.

[0025] During operation, gas enters the central electrode 1 and is ejected through the through-holes 7, forming high-density microbubbles 5 within the discharge reaction zone 4. The strong electric field effect inside the microbubbles 5 and at the gas-liquid interface induces gas-liquid mixed-phase discharge. This invention reduces the breakdown voltage through in-situ microbubbles 5, significantly improving energy utilization. Furthermore, this coaxial integrated structure possesses the significant advantages of low fluid resistance and high gas-liquid interface mass transfer efficiency, making it suitable not only for the deep treatment of recalcitrant organic waste liquids but also for the intensification of processes such as rapid sterilization and gas-liquid multiphase chemical synthesis. This embodiment features a novel coaxial gas-liquid mixed-phase discharge reactor with a simple structure, achieving integrated "gas distribution-discharge" coupling, overcoming the limitations of short-lifetime particle transport, and possessing electrode self-protection capabilities, meeting the high-efficiency requirements of industrial continuous flow treatment.

[0026] like Figure 2 As shown, a gas-liquid mixed-phase discharge device includes the microporous aeration electrode described in this embodiment of the invention, and a housing 10. The microporous aeration electrode is disposed inside the housing 10. The housing 10 is provided with an inlet 11 and an outlet 12. The housing 10 has a cylindrical structure, and the inlet 11 is arranged along the tangential direction of the housing to allow fluid to enter along the tangential direction and form a swirling flow in the discharge reaction zone 4.

[0027] A fluid treatment method using the microporous aeration electrode or gas-liquid mixed-phase discharge device described in the embodiments of the present invention.

[0028] Example 1 like Figure 1 As shown, a microporous aeration electrode has a cylindrical main structure. The core component, the central electrode 1, is a sintered titanium powder tube with a diameter of 20 mm. The titanium sintered tube has good electrical conductivity and corrosion resistance, and its tube wall naturally has uniformly distributed through-hole micropores with an average pore size of approximately 30 μm. The internal cavity of the titanium sintered tube serves as an air inlet channel, and its top end is machined with an external threaded interface for connecting to an external air source such as an air pump or oxygen cylinder, and also serves as a terminal for a high-voltage power supply.

[0029] The outer electrode 2 is made of 304 stainless steel wire mesh, rolled into a cylindrical shape with a diameter of 40 mm, and coaxially sleeved on the outside of the central electrode 1. The stainless steel mesh has a mesh count of 40, which ensures good conductivity and grounding performance while allowing the processed fluid and micro-bubbles to pass through smoothly.

[0030] The insulating support 3 is made of polytetrafluoroethylene. An annular groove is machined on the inner side of the insulating support to prevent deformation of the two ends of the outer electrode 2, which is made of stainless steel wire mesh. The two ends of the titanium sintered tube of the center electrode 1 pass through the central hole of the insulating support 3 and are locked and sealed with hexagonal nuts and flat washers, ensuring that gas can only escape from the micropores in the tube wall and will not leak from the ends.

[0031] The working principle of this embodiment is as follows: When polluted wastewater flows through the discharge reaction zone between the central electrode and the outer electrode, gas is forced in from inside the central electrode. Since the central electrode itself is a conductive high-voltage electrode, when the gas is sheared into microbubbles through the conductive micropores on the pipe wall, the roots of the microbubbles are tightly attached to the edges of the electrode micropores. At this time, the applied high-frequency high-voltage electricity forms an extremely strong electric field concentration at the edges of the conductive micropores. Because the dielectric constant of the gas inside the microbubble is much smaller than that of the surrounding water, the electric field lines preferentially pass through the inside of the bubble, causing the electric field strength inside the bubble and at the gas-liquid interface to reach the breakdown threshold. This mechanism allows the discharge to be precisely confined inside the microbubble that has just detached from the body. This integrated discharge mode not only generates a large amount of ozone, but more importantly, it generates a high concentration of hydroxyl radicals and high-energy electrons at the gas-liquid interface layer. These short-lived particles directly oxidize and decompose the organic pollutants attached to the bubble surface before quenching, achieving efficient in-situ degradation in the gas-liquid mixed-phase system.

[0032] Example 2 Building upon Example 1, improvements were made to the central electrode 1 to further enhance its lifespan under extreme conditions. A surface ceramic modification process was employed to spray a 0.5 mm thick alumina ceramic insulating layer onto the surface of the stainless steel base tube. Before or after spraying, an array of 50 μm diameter pores was fabricated on the tube wall using laser drilling technology. The advantage of this structure is that the ceramic layer acts as a dielectric barrier layer, transforming the discharge mode into dielectric barrier discharge. This not only limits the discharge current, preventing thermal arcing and electrode ablation, but also generates a more uniform streamer discharge, making it particularly suitable for treating industrial wastewater with high conductivity.

[0033] Example 3 like Figure 2 As shown, a gas-liquid mixed-phase discharge device is equipped with an outer casing 10. The outer casing 10 is made of transparent acrylic or UPVC material and covers the outside of the outer electrode 2. The lower part of the outer casing 10 is provided with a tangential water inlet 11, and the upper part is provided with a water outlet 12. When the fluid enters at high speed along the tangential direction, a strong swirling flow is formed in the discharge reaction zone 4. The shear force generated by the swirling flow helps to quickly carry the bubbles that have just emerged from the through-holes 7 away from the electrode surface, preventing the bubbles from merging into large bubbles; at the same time, the high-speed water flow continuously washes the outer electrode 2, effectively preventing suspended matter or flocs in the water from clogging the mesh.

[0034] Example 4 like Figure 3As shown, to verify the performance advantages of the embodiments of the present invention in actual wastewater treatment, the microporous aeration electrode described in Embodiment 1 was immersed in container 13 containing 5 L of simulated wastewater containing the recalcitrant organic pollutant phenol. The initial concentration of the wastewater was 100 mg / L. Driven by a pulse power supply, with a discharge voltage of 15 kV and a discharge frequency of 30 Hz, air was introduced during the discharge process at a gas flow rate of 500 mL / min. A 90% phenol removal rate was achieved after 20 minutes of treatment.

[0035] Example 5 like Figure 3 As shown, to verify the ability of this device to synthesize hydrogen peroxide directly in one step using air and water, and to demonstrate its potential as a chemical reactor, the microporous aeration electrode described in Example 1 was placed in a container 13 containing 5 L of deionized water as the reaction system. An AC power supply was used, with a discharge voltage of 10 kV and a discharge frequency of 3 kHz. Air or oxygen was introduced during the discharge process at a flow rate of 500 mL / min. The high-energy electrons generated by the discharge bombarded water and oxygen molecules, producing hydroxyl radicals and oxygen radicals. These radicals rapidly recombine at the gas-liquid interface to generate H2O2. After 60 minutes of operation, the concentration of hydrogen peroxide in the liquid phase was measured, and the cumulative H2O2 concentration in the water within the container reached over 85 mg / L.

[0036] Example 6 like Figure 3 As shown, to verify the device's rapid killing ability against pathogenic microorganisms, especially its "non-thermal sterilization" using short-lived active particles, the microporous aeration electrode described in Example 1 was immersed in a container 13 containing 5 L of physiological saline suspension containing Escherichia coli. The initial total bacterial count was 1*10⁻⁶. 5 CFU / mL. Driven by a pulse power supply, with a discharge voltage of 15 kV, a discharge frequency of 5 kHz, and air introduced during the discharge process at a gas flow rate of 1 L / min, a sterilization rate of 99.99% can be achieved in just 5 minutes.

[0037] Example 7 like Figure 3As shown, to verify the device's ability to convert nitrogen in the air into nitrate and nitrite nitrogen fertilizer in the liquid phase, the microporous aeration electrode described in Example 1 was placed in a container 13 containing 5 L of ordinary tap water. Driven by a pulsed power supply, with a discharge voltage of 20 kV and a discharge frequency of 3 kHz, air or nitrogen was introduced during the discharge process at a gas flow rate of 500 mL / min. The high-energy electrons generated by the discharge bombard water, oxygen, and nitrogen molecules, producing hydroxyl and nitrogen free radicals. These free radicals rapidly recombine at the gas-liquid interface to generate nitrate and nitrite. After 10 minutes of operation, high concentrations of nitrate and nitrite were detected, and the total nitrogen concentration increased from approximately 0 to 120 mg / L. This device utilizes the high-density plasma generated by the microporous electrode to efficiently break the extremely stable nitrogen-nitrogen triple bonds in the air, causing them to react with oxygen to generate nitrogen oxides, which then rapidly dissolve in the water. Thanks to the high specific surface area of ​​the microbubbles, the NO generated in the gas phase... x It can be transferred to the liquid phase extremely rapidly to form nitrate ions, and its nitrogen fixation efficiency is far higher than that of traditional large-bubble aeration discharge devices. This proves that this device can serve as a highly efficient distributed liquid nitrogen fertilizer generator.

[0038] Example 8 To verify the application potential of this device in algae removal in eutrophic waters, particularly its effectiveness in enhancing algal cell disruption and preventing algal adhesion using swirling shear force, a gas-liquid mixed-phase discharge device with a tangential inlet shell (Example 3) was used to treat a simulated cyanobacterial bloom containing *Microcystis aeruginosa*. The initial chlorophyll a concentration was 1500 μg / L, and the treatment volume was 5 L. A high-frequency, high-voltage pulsed power supply was used, with a discharge voltage of 18 kV and a frequency of 1 kHz. Air was used as the gas source at a flow rate of 1 L / min. Water was injected at high speed through the tangential inlet, creating a strong swirling current within the reactor. During the treatment, the shock waves and active free radicals generated by the discharge destroyed the algal cell air sacs and cell walls; simultaneously, the strong swirling shear force effectively stripped algal cells and extracellular polymers that might have adhered to the electrode surface. After 15 minutes of treatment, the algal cell removal rate was found to be over 95%. Furthermore, after stopping the machine for inspection, the surfaces of the central microporous electrode and the outer mesh electrode were found to be smooth with no obvious algal sludge deposition, demonstrating the self-cleaning advantage of this structure when treating high-viscosity algal solutions.

[0039] Example 9 To verify the technical advantages of the "cyclone shearing injection" method over the "ordinary immersion treatment" method in suppressing algal residue clogging of electrodes, a comparative experiment was conducted. The experimental group used the gas-liquid mixed-phase discharge device described in Example 3, with a circulating pump to create a tangential cyclone. The control group used the microporous aeration electrode described in Example 1, immersed in a static algal solution container of the same volume. Both treated high-concentration aged algal solutions containing a large amount of dead algae and sticky cell debris. After continuous operation for 15 minutes under the same discharge parameters, it was found that in the control group, due to the lack of fluid flushing, a large amount of dead algal residue and flocs were adsorbed onto the surface of the stainless steel mesh outer electrode and the internal microporous electrode, resulting in a darker discharge color, significant fluctuations in discharge current, and uneven aeration due to some micropores being clogged by organic matter. In contrast, the experimental group benefited from the continuous flushing of the electrode surface by the high-speed cyclone, which quickly carried the algal residue away from the discharge area, keeping the electrode surface clean and resulting in uniform and stable discharge glow. The final test results showed that the algae kill rate of the experimental group was 35% higher than that of the control group, which proved that the swirling shear structure can not only enhance mass transfer, but also effectively solve the common problems of "biofilm pollution" and "micropore blockage" in plasma algae removal.

[0040] Example 10 like Figure 4 As shown, this embodiment was designed to verify the discharge stability of the present invention when treating industrial wastewater with high conductivity. In this embodiment, a dielectric barrier structure is provided between the central electrode 1 and the outer electrode 2. The dielectric barrier structure includes an inner barrier layer disposed on the outer wall of the central electrode, or an outer barrier layer disposed on the inner wall of the outer electrode, or a dual dielectric barrier layer containing both an inner and outer barrier layer. When the dielectric barrier structure includes an inner barrier layer, a connecting vent is provided on the inner barrier layer at the position corresponding to the micropore penetrating the central electrode to ensure that gas can be ejected normally. The dielectric barrier structure can also be a solid insulating isolator disposed between the central electrode and the outer electrode; the material of the solid insulating isolator is selected from one or more of ceramics, quartz, glass, polytetrafluoroethylene, or composite insulating materials; the structural form of the solid insulating isolator is a porous tube, a sintered mesh tube, or a fiber diaphragm. The solid insulating isolator allows gas and fluid to pass through and forms a micro-discharge channel within the pores.

[0041] Specifically, based on Example 1, this embodiment incorporates a 2 mm thick porous quartz glass tube as an outer barrier layer 14 and an inner barrier layer 15, tightly attached to the inner wall of the central electrode 1. The tube wall has uniformly distributed through-holes to ensure fluid passage. This device was applied to simulated high-salt wastewater with a conductivity of 15 mS / cm, driven by a pulsed power supply. Experiments revealed that, for the unobstructed structure of Example 1, due to the high conductivity of the wastewater, the input electrical energy was mainly dissipated as Joule heat, causing the water to rapidly heat up and boil, making it difficult to excite an effective non-equilibrium plasma reaction. In contrast, this embodiment benefits from the dielectric barrier effect of the quartz glass tube, which cuts off the liquid-phase conduction current, effectively suppressing the ineffective Joule heating effect and changing the discharge mode to dielectric barrier discharge. This mechanism ensures that the high-voltage electric field energy is concentrated to excite highly active low-temperature plasma inside the bubble and within the pores of the quartz tube, rather than heating the water. After two hours of continuous operation, the discharge glow was uniform and stable, and the central electrode showed no corrosion, confirming the excellent energy efficiency and stability of this structure under high conductivity conditions.

[0042] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A microporous aerated electrode, characterized by: The micro-porous aeration electrode comprises a center electrode, an outer electrode and an insulating support for fixing the center electrode and the outer electrode, the center electrode is a hollow structure with an air inlet, the inner cavity of the center electrode can be used as a gas distribution channel, a plurality of through micro-holes are arranged on the side wall of the center electrode, the outer electrode is a flow-through conductive structure and is provided with a grounding end, the outer electrode is arranged outside the center electrode to form a discharge reaction zone between the center electrode and the outer electrode.

2. The microporous, aerated electrode of claim 1, wherein: The center electrode is a hollow tubular structure, the outer electrode is a cylindrical structure or a sheet structure sleeved outside the center electrode, and the insulating support is fixed to both ends of the outer electrode, and the center electrode penetrates through the insulating support to form the air inlet.

3. The microporous aerated electrode of claim 2, wherein: The center electrode is a tubular structure made of a metal pipe or a porous material, the pore size of the through micro-holes is 10 μm-1000 μm, and the center electrode is coaxially arranged with the outer electrode.

4. The microporous, gas-diffusion electrode of claim 3, wherein: The center electrode is a porous metal sintered pipe, a laser-drilled metal pipe or a porous ceramic pipe coated with a conductive coating, the outer electrode is made of a stainless steel wire mesh or a porous metal punched plate, the insulating support comprises an upper end cover and a lower end cover, the inner side of the upper end cover and the lower end cover is provided with an annular positioning groove for embedding and fixing the outer electrode, and the two ends of the center electrode penetrate through the upper end cover and the lower end cover respectively and are sealingly connected with the upper end cover and the lower end cover through fasteners.

5. The microporous, gas-diffusion electrode according to any one of claims 1 to 4, characterized in that: A dielectric barrier structure is arranged between the center electrode and the outer electrode.

6. The microporous, gas-diffusion electrode of claim 5, wherein: The dielectric barrier structure comprises an inner barrier layer arranged on the outer side wall of the center electrode and / or an outer barrier layer arranged on the inner side wall of the outer electrode; when the dielectric barrier structure comprises the inner barrier layer, the inner barrier layer is provided with a communication hole corresponding to the position of the through micro-holes of the center electrode.

7. The microporous, gas-diffusion electrode of claim 5, wherein: The dielectric barrier structure is a solid insulating separator arranged between the center electrode and the outer electrode; the material of the solid insulating separator is selected from one or more of ceramic, quartz, glass, polytetrafluoroethylene or composite insulating material; and the structure form of the solid insulating separator is a porous pipe, a sintered mesh pipe or a fiber diaphragm.

8. A gas-liquid mixed-phase discharge device, characterized by: The micro-porous aeration electrode comprises a center electrode, an outer electrode and an insulating support for fixing the center electrode and the outer electrode, the center electrode is a hollow structure with an air inlet, the inner cavity of the center electrode can be used as a gas distribution channel, a plurality of through micro-holes are arranged on the side wall of the center electrode, the outer electrode is a flow-through conductive structure and is provided with a grounding end, the outer electrode is arranged outside the center electrode to form a discharge reaction zone between the center electrode and the outer electrode.

9. The gas-liquid mixed-phase discharge device according to claim 8, characterized by: The outer shell is a cylindrical structure, and the water inlet is arranged in the tangential direction of the outer shell.

10. A fluid treatment method characterized by: The micro-porous aeration electrode of any one of claims 1-7 or the gas-liquid mixed-phase discharge device of claims 8 or 9 is used.

Images