An organic wastewater degradation device system and method based on photocatalysis and plasma discharge

Abstract

The application provides an organic wastewater degradation device system and method based on photocatalysis and plasma discharge, and the device system comprises a three-dimensional photocatalysis and plasma synergistic degradation reaction device and a wastewater aeration treatment device; the degradation reaction device comprises a coaxial inner cylinder and outer cylinder, a plasma discharge inner electrode, a plasma discharge outer electrode, a glow discharge electrode, a wastewater conveying pipeline, a pulse xenon lamp and a spiral xenon lamp, and the first plasma generation cavity, the wastewater aeration treatment device and the wastewater conveying pipeline are sequentially communicated. The device system provided by the application is designed as a coaxial surrounding type plasma discharge structure, can form gas-liquid secondary degradation on organic wastewater, and can make the spiral xenon lamp emit light by designing glow discharge on both sides of the pipeline and combining the pulse xenon lamp to form uniform three-dimensional xenon light degradation. Further, the degradation process of organic matter is strengthened, and the degradation efficiency of organic wastewater is improved through the synergistic effect of photocatalysis and plasma field.

Description

Technical Field

[0001] This invention belongs to the field of organic wastewater treatment technology, and relates to an organic wastewater treatment device, and more particularly to an organic wastewater degradation device system and method based on photocatalysis and plasma discharge. Background Technology

[0002] With the acceleration of industrialization, the problem of wastewater discharge containing highly toxic and recalcitrant organic pollutants is becoming increasingly serious. Traditional degradation technologies, such as biological methods, chemical oxidation methods, and physical adsorption methods, face bottlenecks such as high cost, low efficiency, and significant risk of secondary pollution. Therefore, developing efficient, economical, and environmentally friendly organic matter degradation technologies has become a key task in environmental governance.

[0003] In recent years, green and efficient catalysis using photocatalysis and plasma discharge technologies has become a research hotspot. Plasma is a high-energy state generated by the interaction of charged particles and neutral gas molecules. During the discharge process, various active substances can be generated, such as free radicals, ozone, and nitrogen oxides, thereby rapidly degrading organic matter. Photocatalysis technology is based on the photochemical reaction of semiconductor photocatalysts under light conditions. It generates strong oxidizing substances through the reaction of electrons with water or oxygen, achieving deep degradation without chemical additives and possessing renewability.

[0004] However, existing organic wastewater degradation treatment devices have significant technical shortcomings in their design.

[0005] CN106006831A discloses a pollution-resistant continuous three-dimensional photocatalytic wastewater treatment device based on an ultraviolet lamp array, in which the photocatalytic units are arranged in parallel arrays to achieve continuous photocatalysis. However, in this structure, the ultraviolet light cannot be evenly distributed throughout the reaction chamber, resulting in the wastewater in the chamber not receiving uniform catalytic degradation from the light source.

[0006] CN115259276A discloses a centrifugal photocatalytic degradation device for wastewater and its usage method. The device includes an ultraviolet lamp inserted into a reaction chamber and a multi-stage catalytic structure. However, the ultraviolet lamp is located at the center of the chamber, while organic wastewater is introduced into the reaction chamber. When the organic wastewater has a high color intensity, ultraviolet light cannot completely penetrate the wastewater, resulting in low photocatalytic degradation efficiency.

[0007] CN117865330A discloses a wastewater degradation device based on dielectric barrier discharge coupled optical waveguide catalysis. The device has a copper rod and a ceramic dielectric inside the outer tube, forming a plasma discharge zone in the outer tube. When wastewater passes through the plasma discharge zone, it is degraded by the active substances of dielectric barrier discharge and ultraviolet light.

[0008] CN115215467A discloses a plasma catalytic oxidation treatment device and method. The device forms a photocatalytic zone and a multifunctional catalytic oxidation zone, and wastewater is degraded by plasma oxidation and catalytic oxidation in sequence.

[0009] Current photocatalytic degradation technology for organic wastewater has obvious shortcomings. On the one hand, the yield of plasma active substances is low and the energy utilization rate is insufficient, while photocatalysis is limited by uneven light source distribution and poor light transmittance of wastewater. On the other hand, each treatment stage actually uses a single technology, making it difficult to further improve the degradation effect.

[0010] Therefore, it is urgent to achieve efficient and uniform degradation of organic pollutants through innovative device design and technological collaboration mechanisms. Summary of the Invention

[0011] The purpose of this invention is to provide an organic wastewater degradation device system based on photocatalysis and plasma discharge. The device innovatively designs an organic wastewater degradation device that enables photocatalysis and plasma to work synergistically to degrade organic wastewater, thereby improving the treatment efficiency of organic wastewater.

[0012] To achieve this objective, the present invention employs the following technical solution:

[0013] In a first aspect, the present invention provides an organic wastewater degradation device system based on photocatalysis and plasma discharge, the organic wastewater degradation device system comprising:

[0014] Three-dimensional photocatalysis and plasma synergistic degradation reaction device and wastewater aeration treatment device;

[0015] The stereophotocatalytic and plasma-synergistic degradation reaction device includes:

[0016] An inner cylinder and an outer cylinder are coaxially arranged, and a hollow structure is formed between the inner cylinder and the outer cylinder;

[0017] The plasma discharge inner electrode forms a hollow structure along the inner wall of the inner cylinder, thereby forming a first plasma generating cavity inside the inner cylinder.

[0018] A plasma discharge external electrode is provided, wherein the plasma discharge external electrode forms a hollow structure along the inner wall of the outer cylinder, and the hollow structure between the inner cylinder and the outer cylinder forms a second plasma generating cavity.

[0019] A glow discharge electrode is disposed inside the second plasma generating chamber and is positioned opposite to each other at both axial ends of the inner cylinder.

[0020] A pulsed xenon lamp is located inside the second plasma generating chamber and forms a hollow annular structure along the inner wall of the inner cylinder.

[0021] Wastewater conveying pipeline, which is installed inside the second plasma generating chamber and located between oppositely arranged glow discharge electrodes, forming a spiral structure along the outer edge of the inner cylinder;

[0022] A spiral xenon lamp is installed in a wastewater conveying pipeline and extends in a spiral shape along the axial direction of the wastewater conveying pipeline.

[0023] The first plasma generating chamber, the wastewater aeration treatment device, and the wastewater conveying pipeline are connected in sequence.

[0024] The degradation device provided by this invention features an innovative structural design, employing a nested plasma discharge inner and outer electrode structure with the electrodes arranged in a surrounding pattern. This forms two coaxial hollow cavities acting as dielectric barrier layers. Utilizing dielectric barrier discharge technology, ozone, hydroxyl radicals, and other active substances are generated within the intermediate cavity and the flow pipe. Ozone generated from the air in the intermediate cavity acts on the organic wastewater, enabling initial degradation of the wastewater at the start of operation. Subsequently, a second degradation process occurs within the flow pipe, driven by the active substances generated by plasma. Simultaneously, glow discharge electrodes on both sides of the flow pipe trigger glow discharges that act on xenon lamps in the wastewater delivery pipeline. These glow discharges, combined with pulsed xenon lamps within the cavity, create a three-dimensional light source surrounding the entire flow pipe. Under the influence of the electric field, the xenon glow discharge is stronger and more penetrating. Under the influence of xenon light, the organic wastewater reacts with electrons in water or oxygen to generate strong oxidizing substances. Furthermore, xenon light also acts as a catalyst. The oxidizing active species generated by the plasma and the free radicals generated by the photocatalyst can work synergistically to produce a stronger oxidation effect, promote the complete degradation of organic matter, and thus complete the degradation of organic wastewater, significantly improving the degradation efficiency of organic matter.

[0025] Preferably, the plasma discharge inner electrode includes a plasma discharge inner positive electrode and a plasma discharge inner negative electrode that are opposite each other along the axial direction of the inner cylinder.

[0026] Preferably, the plasma discharge external electrode includes a plasma discharge positive electrode and a plasma discharge negative electrode that are opposite each other along the axial direction of the inner cylinder.

[0027] In this invention, the positive electrode of the inner plasma discharge electrode is positioned opposite to the positive electrode of the outer plasma discharge electrode, such that the negative electrode of the inner plasma discharge electrode is on the same side of the axis as the positive electrode of the outer plasma discharge electrode.

[0028] Preferably, the glow discharge electrodes are all hollow annular and are sleeved on the outer periphery of the inner cylinder.

[0029] In this invention, the electrodes are arranged in a positive-negative opposite manner, the spiral pipe is always in the plasma electric field, and the distance between the gas-liquid mixture and the electrodes in the spiral pipe flow channel is always equal, thus realizing stable plasma discharge.

[0030] Preferably, the wastewater aeration treatment device includes a liquid storage container and an aeration device disposed in the liquid storage container.

[0031] In this invention, the first plasma generating chamber is connected to an aeration device via a gas pipeline, and the liquid storage container is connected to a wastewater conveying pipeline via a liquid pipeline.

[0032] In this invention, the aeration device is a conventional aeration device in the art, which functions to form bubbles of gas in a liquid. This invention does not limit its specific structure, as long as it can achieve the aeration function.

[0033] Preferably, the device system further includes a power supply unit.

[0034] Preferably, the power supply unit includes a plasma discharge power supply, a glow discharge power supply, and a pulsed xenon lamp power supply.

[0035] Preferably, the plasma discharge power supply is connected to both the inner plasma discharge electrode and the outer plasma discharge electrode.

[0036] Preferably, the glow discharge power supply is connected to the glow discharge electrode.

[0037] Preferably, the pulsed xenon lamp power supply is connected to the pulsed xenon lamp.

[0038] Preferably, the device system further includes a hydrodynamic unit.

[0039] Preferably, the fluid power unit includes an air pump and a hydraulic pump.

[0040] Preferably, the air pump is located between the first plasma generating chamber and the wastewater aeration treatment device.

[0041] Preferably, the hydraulic pump is located between the wastewater aeration treatment device and the wastewater delivery pipeline.

[0042] In a second aspect, the present invention provides a method for degrading organic wastewater based on photocatalysis and plasma discharge, wherein the organic wastewater degradation method uses the organic wastewater degradation device system based on photocatalysis and plasma discharge described in the first aspect.

[0043] Preferably, the organic wastewater degradation method includes the following steps:

[0044] The plasma discharge inner electrode, plasma discharge outer electrode, and glow discharge electrode are energized to form a reaction electric field. The pulsed xenon lamp is energized to emit light, and the spiral xenon lamp in the wastewater conveying pipeline generates glow under the glow discharge electric field. Air is introduced into the first plasma generating chamber, and degradation active substances are generated through plasma discharge. The gas containing degradation active substances is introduced into the wastewater aeration treatment device to aerate the wastewater to be degraded, generating wastewater containing microbubbles to be degraded. Then, the wastewater containing microbubbles to be degraded is introduced into the wastewater conveying pipeline, so that the wastewater to be degraded is degraded under the action of plasma electric field and three-dimensional light.

[0045] In this invention, the first plasma generating chamber is connected to the wastewater conveying pipeline. The degradation of wastewater in the wastewater conveying pipeline is the main degradation process. Therefore, the flow rate of the gas introduced into the first plasma generating chamber is kept the same as the flow rate of the wastewater in the wastewater conveying pipeline.

[0046] The technical principle of plasma discharge in this invention is as follows:

[0047] Plasma is a mixture of electrons, ions, and neutral particles. It is macroscopically electrically neutral, electromagnetic on a small scale, and exhibits collective effects. Plasma can be generated by ionizing molecules and atoms of matter through thermal ionization, photoionization, and collisional ionization.

[0048] When a gas-liquid two-phase fluid is introduced between the positive and negative electrodes, plasma discharge occurs when the applied alternating current voltage exceeds the fluid's breakdown voltage.

[0049] The formula for calculating the voltage applied between the electrodes using coaxial dual-cylinder dielectric barrier plasma discharge technology is as follows:

[0050]

[0051] Where V is the voltage between the plates, in kV; E g t represents the voltage intensity of the gas in the discharge gap, in kV / cm; t represents the thickness of the electrode plate, in cm; l gl ε is the discharge distance when a gas-liquid two-phase flow is introduced between the two electrodes, in cm; ε is the dielectric constant of the gas; ε d is the dielectric constant of the blocking medium.

[0052] The discharge distance when a two-phase fluid (gas and liquid) is introduced between the two electrodes is related to the volume fraction of the gas phase. The formula for calculating the discharge distance is as follows:

[0053] l g l =c·l g

[0054] Where c is the gas phase volume fraction between the two plates, and the value of c is between 0 and 1, which needs to be determined experimentally; l g This is the discharge distance when there is only gas between the two plates.

[0055] When degrading organic wastewater, too low a voltage may lead to unstable or discontinuous discharge, while too high a voltage may lead to excessive discharge, increasing the system's energy consumption and electrode wear.

[0056] The technical principle of glow discharge in this invention is as follows:

[0057] When an electric field is applied to both ends of a gas as an excitation, the gas molecules will produce a discharge phenomenon, generating a considerable amount of plasma field. At the same time, this plasma field will emit glow, that is, ultraviolet light, which is called glow discharge phenomenon.

[0058] The principle for calculating the applied voltage of glow discharge is as follows:

[0059] According to Paschen's law, as the voltage between the discharge electrodes increases, the tube current also increases, and at a certain threshold voltage (breakdown voltage) V... b At this point, a sudden increase in tube current occurs, indicating gas breakdown. Therefore, the relationship between breakdown voltage, gas pressure, and electrode gap is as follows:

[0060]

[0061] Among them, V b γ is the breakdown voltage; A and B are gas type coefficients; P is the gas pressure; d is the electrode gap; se This represents the secondary electron emission coefficient.

[0062] Breakdown voltage V b It is a function of the product of Pd, and has a minimum breakdown voltage at a specific Pd value.

[0063] Different gases have different breakdown voltages. Inert gases (such as argon and neon) have lower breakdown voltages, while molecular gases such as nitrogen and oxygen have higher breakdown voltages. For plasma processing or chemical reactions, oxygen, nitrogen, or a mixture of gases may be chosen. The choice of electrode material affects the secondary electron emission coefficient (γse) and the stability of the discharge. Electrode surface roughness affects the local electric field strength, reducing the breakdown voltage, but may lead to uneven discharge. Surface contamination (such as oil and oxides) affects secondary electron emission and discharge characteristics; therefore, the electrode surface needs to be cleaned.

[0064] Compared with the prior art, the present invention has the following beneficial effects:

[0065] (1) By designing a coaxial surrounding plasma discharge structure and arranging the plasma electrodes in a positive-negative opposite manner, a gas-liquid dual ozone degradation is achieved for organic wastewater.

[0066] (2) By designing glow discharge structures on both sides of the pipeline, the spiral xenon lamp and the ring pulse xenon lamp can form a uniform three-dimensional light degradation. The xenon lamp light source is stronger and has greater penetrating power, so that the wastewater conveying pipeline is irradiated in the full range. At the same time, under the synergistic effect of photocatalysis and plasma electric field, the wastewater can enhance the degradation process of organic matter and improve the degradation efficiency of organic wastewater. Attached Figure Description

[0067] Figure 1 This is a schematic diagram of the organic wastewater degradation device system based on photocatalysis and plasma discharge provided in Example 1;

[0068] Figure 2 This is a schematic diagram of the stereophotocatalytic and plasma-assisted degradation reaction device provided in Example 1;

[0069] Figure 3 This is a top view schematic diagram of the stereophotocatalytic and plasma-assisted degradation reaction device provided in Example 1;

[0070] Figure 4 This is a schematic diagram of the power connection method of the stereophotocatalytic and plasma synergistic degradation reaction device provided in Example 1;

[0071] The components include: 1. Stereoscopic photocatalysis and plasma synergistic degradation reaction device; 11. Top cover; 12. Bottom cover; 13. Inner cylinder side wall; 14. Outer cylinder side wall; 15. First plasma generating chamber; 16. Second plasma generating chamber; 151. Gas inlet; 152. Gas outlet; 161. Wastewater inlet; 162. Wastewater outlet; 17. Inner electrode of plasma discharge; 171. Inner positive electrode of plasma discharge; 172. Inner negative electrode of plasma discharge; 18. Outer electrode of plasma discharge; 181. Outer positive electrode of plasma discharge; 182. Outer negative electrode of plasma discharge; 191. Positive electrode of glow discharge; 192. Negative electrode of glow discharge; 110. Ring pulse xenon lamp; 111. Spiral xenon lamp; 112. Wastewater conveying pipeline; 2. Wastewater aeration treatment device; 21. Aeration device; 3. Wastewater collection tank; 4. Plasma discharge power supply; 5. Glow discharge power supply; 6. Pulse xenon lamp power supply; 7. Air pump; 8. Hydraulic pump. Detailed Implementation

[0072] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0073] Example 1

[0074] This embodiment provides an organic wastewater degradation device system based on photocatalysis and plasma discharge.

[0075] The organic wastewater degradation device system includes:

[0076] The system includes: 1. a stereocatalytic and plasma-assisted degradation reaction device; 2. a wastewater aeration treatment device; 3. a wastewater collection tank; 4. a power supply unit and a fluid power unit.

[0077] The stereophotocatalytic and plasma-assisted degradation reaction device 1 includes:

[0078] The system comprises a top cover 11, a bottom cover 12, an inner cylindrical side wall 13, and an outer cylindrical side wall 14. The inner cylindrical side wall 13 and the outer cylindrical side wall 14 are two hollow cylindrical structures of the same height. The inner cylindrical side wall 13 is located within the outer cylindrical side wall 14 and is coaxially arranged with it, forming a hollow structure between them. The two ends of the inner cylindrical side wall 13 and the outer cylindrical side wall 14 are respectively joined and sealed to the top cover 11 and the bottom cover 12. The top cover 11 and the bottom cover 12 are fixed together by bolts. Gaskets are provided on the contact surfaces of the bolts with the top cover 11 and the bottom cover 12 to ensure the airtightness of the cavity. Finally, an inner cylinder is formed between the inner cylinder sidewall 13, the top cover 11, and the bottom cover 12. The interior of the inner cylinder is the first plasma generating chamber 15. An outer cylinder is formed between the outer cylinder sidewall 14, the top cover 11, and the bottom cover 12. The hollow structure formed between the inner and outer cylinders is the second plasma generating chamber 16.

[0079] The plasma discharge inner electrode 17 is divided into a plasma discharge positive electrode 171 and a plasma discharge negative electrode 172. The plasma discharge positive electrode 171 forms a semi-circular structure with an arc angle of 180° along the inner wall of the inner cylinder. The plasma discharge negative electrode 172 starts from one end of the plasma discharge positive electrode 171 and forms a semi-circular structure with an arc angle of 180° along the inner wall of the inner cylinder, connecting with the other end of the plasma discharge positive electrode 171. Thus, the plasma discharge positive electrode 171 and plasma discharge negative electrode 172 are connected at both ends to form a hollow cylinder. Grooves are opened on the top cover 11 corresponding to the positions of the inner positive electrode and the inner negative electrode for insertion with the two electrode plates, and are fixed by the slot bolts on the bottom cover 12.

[0080] The plasma discharge external electrode 18 is divided into a positive plasma discharge electrode 181 and a negative plasma discharge electrode 182. The positive plasma discharge electrode 181 forms a semi-circular structure with an arc angle of 180° along the inner wall of the outer cylinder. The negative plasma discharge electrode 182 starts from one end of the positive plasma discharge electrode 181 and forms a semi-circular structure with an arc angle of 180° along the inner wall of the outer cylinder, connecting to the other end of the positive plasma discharge electrode 181. This results in the positive plasma discharge electrode 181 and the negative plasma discharge electrode 182 forming a hollow cylinder. Grooves are provided on the top cover 11 corresponding to the positions of the positive and negative electrodes for insertion with the two electrode plates, and are fixed by the slot bolts on the bottom cover 12. The inner positive electrode 171 of the plasma discharge and the outer positive electrode 181 of the plasma discharge are in relative positions. Similarly, the inner negative electrode 172 of the plasma discharge and the outer negative electrode 182 of the plasma discharge are also in relative positions, so that the inner negative electrode 172 of the plasma discharge and the outer positive electrode 181 of the plasma discharge are on the same side of the inner cylinder axis, and the inner positive electrode 171 of the plasma discharge and the outer negative electrode 182 of the plasma discharge are on the same side of the inner cylinder axis.

[0081] The glow discharge electrode is divided into a glow discharge positive electrode 191 and a glow discharge negative electrode 192. Both the glow discharge positive electrode 191 and the glow discharge negative electrode 192 are hollow annular and are sleeved on the outer periphery of the inner cylinder, thus located inside the second plasma generating cavity 16, and are respectively fixed to both ends of the inner cylinder in the axial direction by fixing bosses.

[0082] The annular pulsed xenon lamp 110 is located inside the second plasma generating chamber 16, and forms a hollow annular structure along the inner wall of the inner cylinder on the inner side of the plasma discharge outer electrode 18.

[0083] The spiral xenon lamp 111 is located inside the second plasma generating chamber 16. It starts from one end of the inner cylinder in the axial direction and spirals around the outer circumference of the inner cylinder until it ends at the other end of the inner cylinder in the axial direction, so that the spiral part of the spiral xenon lamp is located between the glow discharge positive electrode 191 and the glow discharge negative electrode 192.

[0084] Wastewater delivery pipeline 112 is located inside the second plasma generating chamber 16. The outer wall of the wastewater delivery pipeline 112 is wrapped with a spiral xenon lamp 111, so that the wastewater delivery pipeline 112 is also spirally wrapped around the outer periphery of the inner cylinder. The spiral xenon lamp 111 is located in the wastewater delivery pipeline 112, and the spiral part of the wastewater delivery pipeline 112 is located between the glow discharge positive electrode 191 and the glow discharge negative electrode 192.

[0085] A gas inlet 151 is provided on the top cover of the first plasma generating chamber 15, and a gas outlet 152 is provided on the bottom cover of the first plasma generating chamber 15, so that gas can enter and exit the first plasma generating chamber 15.

[0086] A wastewater inlet 161 is provided on the top cover of the second plasma generating chamber 16, and a wastewater outlet 162 is provided on the bottom cover of the second plasma generating chamber. The two ends of the wastewater conveying pipeline 112 are connected to the wastewater inlet 161 and the wastewater outlet 162, respectively.

[0087] The wastewater aeration treatment device 2 includes a storage tank and an aeration device 21 installed inside the storage tank.

[0088] The power supply unit includes a plasma discharge power supply 4, a glow discharge power supply 5, and a pulsed xenon lamp power supply 6.

[0089] The power supply units in this device are plasma discharge power supply 4, glow discharge power supply 5, and pulsed xenon lamp power supply 6. For example... Figure 4 As shown, the connection method is as follows: the negative terminal of the plasma discharge power supply 4 is connected to the inner negative terminal 172 and the outer negative terminal 182 of the plasma discharge via a wire; the positive terminal of the plasma discharge power supply 4 is connected to the inner positive terminal 171 and the outer positive terminal 181 of the plasma discharge via a wire, thereby realizing plasma discharge. The glow discharge power supply 5 is connected to the glow discharge positive terminal 191 and the glow discharge negative terminal 192 via wires to realize the glow discharge of the spiral xenon lamp 111. The pulse xenon lamp power supply 6 is connected to the ring pulse xenon lamp 110 to generate xenon light, which together with the xenon light generated by the spiral xenon lamp 111 forms a three-dimensional xenon light.

[0090] The fluid power unit includes an air pump 7 and a hydraulic pump 8.

[0091] The first plasma generating chamber 15, the air pump 7, the wastewater aeration treatment device 2, the hydraulic pump 8, the wastewater conveying pipeline 112, and the wastewater collection tank 3 are connected in sequence. Specifically, the first plasma generating chamber 15 is connected to the air pump 7 through the gas outlet 152. The air pump 7 is connected to the aeration device 21 in the wastewater aeration treatment device 2. The storage tank of the wastewater aeration treatment device 2 is connected to the hydraulic pump 8. The hydraulic pump 8 is connected to the wastewater conveying pipeline 112 through the wastewater inlet 161. The wastewater conveying pipeline 112 is connected to the wastewater collection tank 3 through the wastewater outlet 162.

[0092] In this embodiment, the plasma power supply is a Suman CTP-2000K AC plasma power supply. The top cover, bottom cover, inner cavity sidewalls, and outer cavity sidewalls are all made of non-insulating materials, specifically polytetrafluoroethylene (PTFE), avoiding the use of metal materials to prevent interference between the plasma discharge electrodes and the glow discharge electrodes. To ensure that the wastewater delivery pipeline within the device can be penetrated by xenon light and that the spiral xenon lamp can be placed inside the wastewater delivery pipeline, a polyethylene film is used to make the outer shell of the wastewater delivery pipeline.

[0093] In this embodiment, for plasma discharge, the thickness of the electrode plate is 2cm, the discharge distance when a gas-liquid two-phase fluid is introduced between the two electrodes is 4cm, the dielectric constant of the gas is 1, the dielectric constant of the quartz glass is 3.7, and according to Paschen's law, the breakdown voltage of the gas under standard atmospheric pressure is 30kV / cm. Finally, the minimum voltage applied between the electrodes is calculated to be 92.4kV.

[0094] Therefore, in this embodiment, the voltage finally applied to the plasma discharge electrode is 93kV.

[0095] In this embodiment, for glow discharge, the spiral xenon lamp is filled with xenon gas. The gas species constant A of the xenon gas is 15 (1 / (Pa·m)), B is 250 (V / (Pa·m)), the gas pressure P of the xenon gas is 70 kPa, the electrode material is aluminum metal, and the secondary electron emission coefficient γ... se With a value of 0.1 and a gap d between the electrode plates of 80 cm, the minimum voltage for glow discharge time is calculated to be 98.2 kV.

[0096] Therefore, in this embodiment, the final voltage applied to the glow discharge electrode is 100kV. The voltage applied to the ring-shaped xenon lamp is also 100kV.

[0097] This embodiment also provides a method for degrading organic wastewater based on photocatalysis and plasma discharge. The method uses the aforementioned organic wastewater degradation device system based on photocatalysis and plasma discharge, and includes the following steps:

[0098] (1) After the spiral xenon lamp 111 is filled with xenon gas, it is sealed by a piston. The air pump 7 and the plasma discharge power supply 4 are turned on, and the air outside the system is introduced into the first plasma generating chamber 15 at a speed of 0.8L / min. The first plasma generating chamber 15 receives plasma discharge and generates a gaseous mixture of ozone and air.

[0099] (2) The gaseous mixture is introduced into the aeration device 21 through the pipeline to aerate the organic wastewater and form organic wastewater rich in microbubbles.

[0100] (3) Open the wastewater inlet 161 and the wastewater outlet 162, and at the same time turn on the hydraulic pump 8. The hydraulic pump 8 draws the organic wastewater rich in microbubbles from the wastewater aeration treatment device 2 and enters the wastewater inlet 161 at a speed of 0.8L / min, and then flows into the wastewater conveying pipeline 112.

[0101] (4) Turn on the glow discharge power supply 5 and the pulse xenon lamp power supply 6. Organic wastewater rich in microbubbles enters the wastewater conveying pipeline 112. The spiral xenon lamp 111 generates three-dimensional xenon light through glow discharge and the ring pulse xenon lamp 110. Plasma discharge generates ozone, hydroxyl radicals and other active substances in the wastewater. The xenon light and plasma work together to degrade the organic matter in the wastewater.

[0102] (5) After the pipeline is filled with solution, the degraded organic wastewater overflows from wastewater outlet 162 into wastewater collection tank 3 by water pressure;

[0103] (6) The pollutant removal rate of the degraded wastewater is detected and the hydraulic pump flow rate is adjusted in real time.

[0104] Comparative Example 1

[0105] This comparative example provides a device system for degrading organic wastewater. Compared with Example 1, the stereophotocatalytic and plasma synergistic degradation reaction device does not have an internal plasma discharge electrode, but all other aspects are the same as in Example 1.

[0106] This comparative example also provides a method for degrading organic wastewater using the aforementioned apparatus system for degrading organic wastewater, and the operation steps of the method are the same as those in Example 1.

[0107] Comparative Example 2

[0108] This comparative example provides a device system for degrading organic wastewater. Compared with Example 1, the stereophotocatalytic and plasma synergistic degradation reaction device does not have an external plasma discharge electrode, but all other aspects are the same as in Example 1.

[0109] This comparative example also provides a method for degrading organic wastewater using the aforementioned apparatus system for degrading organic wastewater, and the operation steps of the method are the same as those in Example 1.

[0110] Comparative Example 3

[0111] This comparative example provides a device system for degrading organic wastewater. Compared with Example 1, the stereocatalytic and plasma synergistic degradation reaction device does not have a glow discharge electrode and a glow discharge power supply, but all other aspects are the same as in Example 1.

[0112] This comparative example also provides a method for degrading organic wastewater using the aforementioned apparatus system for degrading organic wastewater. In this method, no glow discharge is applied, and the remaining operating steps are the same as in Example 1.

[0113] Comparative Example 4

[0114] This comparative example provides a device system for degrading organic wastewater. Compared with Example 1, the stereocatalytic and plasma synergistic degradation reaction device does not include a ring pulse xenon lamp and a xenon lamp power supply, but all other aspects are the same as in Example 1.

[0115] This comparative example also provides a method for degrading organic wastewater using the aforementioned apparatus system for degrading organic wastewater. In this method, no annular xenon lamp light source is applied, and the remaining operating steps are the same as in Example 1.

[0116] Comparative Example 5

[0117] This comparative example provides a device system for degrading organic wastewater. Compared with Example 1, the plasma discharge external electrode is divided into a plasma discharge positive electrode and a plasma discharge negative electrode. Both the plasma discharge positive electrode and the plasma discharge negative electrode are hollow rings, sleeved on the outer periphery of the inner cylinder, and thus located inside the second plasma generating cavity. They are fixed to both ends of the inner cylinder in the axial direction by fixing bosses. The glow discharge electrode is divided into a glow discharge positive electrode and a glow discharge negative electrode. The glow discharge positive electrode forms a semi-circular structure with an arc angle of 180° along the inner wall of the outer cylinder. The glow discharge negative electrode forms a semi-circular structure with an arc angle of 180° starting from one end of the glow discharge positive electrode along the inner wall of the outer cylinder and connects to the other end of the glow discharge positive electrode, thus forming a hollow cylinder with the glow discharge positive electrode and the glow discharge negative electrode connected at both ends. The rest is the same as in Example 1, that is, the structures of the plasma discharge external electrode and the glow discharge electrode are interchanged.

[0118] This comparative example also provides a method for degrading organic wastewater, using the aforementioned apparatus system for degrading organic wastewater, with the remaining operating steps being the same as in Example 1.

[0119] The apparatus, system, and method provided in the examples and comparative examples were used to degrade organic wastewater. The composition of the organic wastewater was as follows: humic acid / fulvic acid: 50 mg / L, lignin derivatives (paper or wood processing wastewater): 20 mg / L, synthetic organic matter, dye / pigment residues (textile and printing and dyeing wastewater): 5 mg / L, surfactants (detergent and chemical wastewater): 10 mg / L, organic acids and alcohols (food processing and fermentation wastewater): 200 mg / L (COD calculation), proteins and fats (domestic sewage): 10 mg / L, iron / manganese ions (color development after oxidation): 1 mg / L, benzene series compounds and phenols (chemical wastewater): 2 mg / L, ammonia nitrogen (domestic sewage): 5 mg / L. The total organic carbon (TOC) analysis method was used to analyze the components of the wastewater before and after degradation, and the removal rate of organic matter was calculated and listed in Table 1.

[0120] Table 1

[0121] Example 1 98 Comparative Example 1 87 Comparative Example 2 84 Comparative Example 3 88 Comparative Example 4 91 Comparative Example 5 78

[0122] As shown in Table 1, compared with Comparative Examples 1-5, the device system provided by this invention achieves excellent organic matter degradation and removal effects when treating organic wastewater with various complex components, with a degradation rate as high as 98%. When lacking, for example, plasma discharge, glow discharge, or xenon lamp stereoscopic light, the removal effect significantly deteriorates. When the glow discharge portion does not generate stereoscopic light together with the ring pulse xenon lamp, the removal rate also decreases significantly, indicating that while the three methods individually degrade organic matter, they also produce a synergistic mechanism, further enhancing the degradation effect. When the glow discharge electrode and plasma discharge electrode in the device are interchanged, the different length, width, and height of the device (i.e., the different voltages required when the electrodes are at the left and right ends and the top and bottom ends) cannot meet the needs of the corresponding discharge portions, resulting in a significant decrease in the removal rate.

[0123] In summary, the device system provided by this invention achieves gas-liquid two-stage degradation of organic wastewater through the design of a coaxial surrounding plasma discharge structure. By designing glow discharge structures on both sides of the pipeline and combining them with a ring pulse xenon lamp, a uniform three-dimensional photodegradation is formed. Furthermore, the xenon lamp light source is stronger and has greater penetrating power. Under the synergistic effect of photocatalysis and the plasma field, the degradation process of organic matter is enhanced, thereby improving the degradation efficiency of organic wastewater.

[0124] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. An organic wastewater degradation device system based on photocatalysis and plasma discharge, characterized in that, The organic wastewater degradation device system includes: Three-dimensional photocatalysis and plasma synergistic degradation reaction device and wastewater aeration treatment device; The stereophotocatalytic and plasma-synergistic degradation reaction device includes: An inner cylinder and an outer cylinder are coaxially arranged, and a hollow structure is formed between the inner cylinder and the outer cylinder; The plasma discharge inner electrode forms a hollow structure along the inner wall of the inner cylinder, thereby forming a first plasma generating cavity inside the inner cylinder. A plasma discharge external electrode is provided, wherein the plasma discharge external electrode forms a hollow structure along the inner wall of the outer cylinder, and the hollow structure between the inner cylinder and the outer cylinder forms a second plasma generating cavity; A glow discharge electrode is disposed inside the second plasma generating chamber and is positioned opposite to each other at both axial ends of the inner cylinder. A pulsed xenon lamp is located inside the second plasma generating chamber and forms a hollow annular structure along the inner wall of the inner cylinder. Wastewater conveying pipeline, which is installed inside the second plasma generating chamber and located between oppositely arranged glow discharge electrodes, forming a spiral structure along the outer edge of the inner cylinder; A spiral xenon lamp is installed in a wastewater conveying pipeline and extends in a spiral shape along the axial direction of the wastewater conveying pipeline. The first plasma generating chamber, the wastewater aeration treatment device, and the wastewater conveying pipeline are connected in sequence. The wastewater aeration treatment device includes a liquid storage container and an aeration device installed in the liquid storage container. The organic wastewater degradation device system also includes a fluid power unit; The fluid power unit includes an air pump and a hydraulic pump; The air pump is located between the first plasma generating chamber and the wastewater aeration treatment device. The hydraulic pump is installed between the wastewater aeration treatment device and the wastewater delivery pipeline.

2. The organic wastewater degradation device system according to claim 1, characterized in that, The plasma discharge inner electrode includes a plasma discharge positive electrode and a plasma discharge negative electrode that are opposite each other along the axial direction of the inner cylinder.

3. The organic wastewater degradation device system according to claim 1, characterized in that, The plasma discharge external electrode includes a plasma discharge positive electrode and a plasma discharge negative electrode that are opposite each other along the axial direction of the inner cylinder.

4. The organic wastewater degradation device system according to claim 1, characterized in that, The glow discharge electrodes are all hollow annular and are sleeved on the outer periphery of the inner cylinder.

5. The organic wastewater degradation device system according to claim 1, characterized in that, The organic wastewater degradation device system also includes a power supply unit.

6. The organic wastewater degradation device system according to claim 5, characterized in that, The power supply unit includes a plasma discharge power supply, a glow discharge power supply, and a pulsed xenon lamp power supply.

7. The organic wastewater degradation device system according to claim 6, characterized in that, The plasma discharge power supply is connected to the plasma discharge inner electrode and the plasma discharge outer electrode, respectively.

8. The organic wastewater degradation device system according to claim 6, characterized in that, The glow discharge power supply is connected to the glow discharge electrode.

9. The organic wastewater degradation device system according to claim 6, characterized in that, The pulsed xenon lamp power supply is connected to the pulsed xenon lamp.

10. A method for degrading organic wastewater based on photocatalysis and plasma discharge, characterized in that, The organic wastewater degradation method uses the organic wastewater degradation device system based on photocatalysis and plasma discharge as described in any one of claims 1-9.

11. The method for degrading organic wastewater according to claim 10, characterized in that, The organic wastewater degradation method includes the following steps: The plasma discharge inner electrode, plasma discharge outer electrode, and glow discharge electrode are energized to form a reaction electric field. The pulsed xenon lamp is energized to emit light, and the spiral xenon lamp in the wastewater conveying pipeline generates glow under the glow discharge electric field. Air is introduced into the first plasma generating chamber, and degradation active substances are generated through plasma discharge. The gas containing degradation active substances is introduced into the wastewater aeration treatment device to aerate the wastewater to be degraded, generating wastewater containing microbubbles to be degraded. Then, the wastewater containing microbubbles to be degraded is introduced into the wastewater conveying pipeline, so that the wastewater to be degraded is degraded under the synergistic effect of the plasma electric field and three-dimensional light.

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