Liquid-phase bubble induced discharge plasma oxidation water treatment device and treatment method

Abstract

The invention relates to a liquid-phase bubble induced discharge plasma oxidation water treatment device and a treatment method, and particularly belongs to the technical field of water treatment. The water treatment device provided by the invention comprises a plasma reactor, the plasma reactor comprises a high borosilicate glass container, the bottom end of the high borosilicate glass container is connected with a flange plate, openings are formed in the middle of the high borosilicate glass container and the middle of the flange plate, glass tubes are mounted at the openings, stainless steel tubes are sleeved with the glass tubes, and the stainless steel tubes are connected with the high borosilicate glass container. The liquid-phase bubble discharge mode is adopted, the influence of the solution conductivity on the plasma state is overcome, and under the condition of high conductivity, plasma discharge can be triggered, and the water treatment and purification effect is good. And in addition, under the condition that the breakdown voltage and the energy consumption are reduced, the technical effect that large-volume plasma can be generated in water / liquid can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of water treatment, and particularly relates to a liquid-phase bubble induced discharge plasma oxidation water treatment device and a treatment method. Background Art

[0002] Discharge plasma technology is a new treatment technology that integrates physical, chemical and other comprehensive effects. Gas or liquid molecules in the discharge area collide and ionize under the action of a strong electric field, producing active particles with strong oxidizing or reducing properties, accompanied by physical effects such as ultraviolet light, shock waves and thermal effects. In recent years, water treatment processes based on discharge plasma technology have attracted widespread attention. Plasma participates in chemical reactions by providing high-energy electrons, ions, active free radicals, excited atoms and molecules, and combines multiple physical effects to achieve rapid degradation of organic pollutants in water. Therefore, it has incomparable advantages over traditional pollutant degradation technologies, such as the production of abundant active species, no need to add additional chemical agents and no secondary pollution. Domestic and foreign scholars have applied this technology to the degradation of toxic organic pollutants and the inactivation of microorganisms, and have achieved good treatment results.

[0003] Plasma can be generated by gas discharge or liquid discharge. Since the mean free path of electrons in liquid is small, a very high electric field is required for the collision ionization process to occur, while gas discharge requires lower electric field conditions, so gas discharge is usually used to generate plasma. However, in the plasma water treatment process, the active species generated by gas phase discharge cannot be directly injected into the liquid phase, but need to react with organic pollutants in the liquid phase through the gas-liquid interface and the mass transfer process of the liquid phase. This process will inevitably weaken the effect of active species on organic pollutants. It can be seen that gas-liquid mass transfer and energy efficiency issues are bottleneck issues that limit the further development of discharge plasma water treatment technology.

[0004] Therefore, many studies have attempted to solve this problem by optimizing the discharge structure of the plasma reactor or using gas-liquid mixed discharge. For example, the mass transfer of active substances is improved by expanding the plasma-water interface, including: plasma bubbles, descending water film and atomization / droplets. Bubbling gaseous plasma into water through plasma bubbles increases the form of the gas-liquid mass transfer interface, thereby improving the utilization efficiency of active substances. The liquid to be treated flows through the discharge area in the form of a liquid film, and the gas-liquid specific surface area is increased and the gas-liquid mass transfer is enhanced by the liquid film flow. The utilization efficiency of active substances and the removal efficiency of organic pollutants are improved. In addition, passing water through the plasma discharge area in the form of droplets can also improve the utilization efficiency of active substances, and the presence of droplets can promote plasma discharge.

[0005] Existing patents provide some solutions, such as patent JP2023039554A, which provides a plasma water treatment device having a discharge unit and a power supply for generating plasma. The discharge unit has a high-voltage electrode, a ground electrode, and a dielectric between the high-voltage electrode and the ground electrode, and there is a rare gas between the high-voltage electrode and the ground electrode. The plasma generation power supply applies an alternating voltage between the high-voltage electrode and the ground electrode, so that the plasma contacts the liquid surface of the treated water, generates OH radicals in the treated water, and treats harmful substances in the water. This method can achieve the technical effect of efficiently purifying pollutants in water to a certain extent, but the effect is limited, and the problem of low gas-liquid mass transfer efficiency of active species still exists. Here, the inventor believes that there is still a lot of room for improvement. Summary of the invention

[0006] The present invention can not only generate a large number of bubbles in the liquid phase by aeration, in-situ induce bubble discharge to generate a large number of active species, but also increase gas-liquid mass transfer to improve the utilization efficiency of active species and reduce energy consumption, but also the device has a simple structure, is easy to operate, and has the potential for industrial scale-up application.

[0007] The present invention provides a liquid-phase bubble induced discharge plasma oxidation water treatment device, which comprises a plasma reactor, wherein the plasma reactor comprises a glass container, wherein the bottom end of the glass container is connected to a flange plate, wherein openings are arranged between the glass container and the flange plate, wherein a glass tube is installed at the opening, wherein a stainless steel tube is sleeved inside the glass tube, wherein the stainless steel tube is fixed to the flange plate through a flange, and wherein a ferrule is connected to the end of the stainless steel tube.

[0008] Furthermore, a removable upper cover is installed on the top of the glass container, and the glass container contains liquid to be treated, wherein a bottom bracket and a stainless steel hexagonal knob are also installed at the bottom of the glass container, and the stainless steel hexagonal knob cooperates with the bottom bracket, and the stainless steel hexagonal knob can be rotated to adjust the height of the bottom bracket, and the bottom bracket and the stainless steel hexagonal knob are assembled together to support the glass container.

[0009] In the present invention, the hollow stainless steel tube is connected to the air inlet pipe through a PTFE ferrule as an air inlet part, and on the other hand, the stainless steel tube is connected to the high voltage end of the pulse power supply as a high voltage electrode of the plasma reactor.

[0010] Furthermore, the high-voltage power supply includes a DC power supply for generating a DC voltage signal, a high-voltage generator for converting the DC voltage signal into a pulse voltage signal, and a frequency generator for controlling the frequency of the pulse signal. The DC power supply is connected to the high-voltage generator through a wire, and the high-voltage generator is connected to the frequency generator through a wire. The frequency generator leads to a high-voltage output end of the power supply and a ground electrode end through a high-voltage power line. The high-voltage output end of the power supply is used to connect a high-voltage electrode in a plasma reactor, and the high-voltage electrode is used as an energy input port of the plasma reactor. In addition, the frequency generator can adjust the frequency of the pulse signal, and a knob is provided on the DC power supply to adjust the output voltage of the bipolar pulse high-voltage power supply.

[0011] In the present invention, an upper cover is provided at the upper end of the glass container, and a hole is opened in the upper cover. An exhaust pipe is adapted to be arranged in the hole, and a processing device is connected to the output end of the exhaust pipe.

[0012] The processing device of the present invention is provided with a potassium iodide solution for absorbing gas, and the processing device is also provided with an air outlet pipe.

[0013] Furthermore, the treatment device is mainly used to absorb gases such as ozone generated by the reaction in the glass container, wherein the gas is input into the glass container through a ferrule, and the gas passes through a stainless steel tube and a glass tube with fine pores to form a large number of bubbles in the glass container filled with liquid. At the same time, the high-voltage power supply provides a pulsed high voltage to the ground electrode in the plasma reactor. Under the action of the high-voltage electric field, discharge is first triggered at the fine pore channels of the stainless steel tube and the glass tube, and streamers are derived in the bubbles, and further develop to the surface of the bubbles to generate active substances by plasma discharge reaction, and the active substances react with organic matter in the liquid to achieve the purpose of purifying the liquid.

[0014] In the present invention, a gland is provided on the top of the glass container, a grounding electrode is sleeved on the outer side of the glass tube, and the grounding electrode is assembled with the gland through a plastic nut.

[0015] In the present invention, at least one fine hole is provided at the bottom of the glass tube and the bottom of the stainless steel tube, and the fine hole at the bottom of the glass tube and the fine hole at the bottom of the stainless steel tube are both located on the same axis.

[0016] Furthermore, the quartz glass tube for isolating metal from liquid, which is mounted outside the stainless steel tube, has eight fine holes evenly distributed at the bottom, and the stainless steel tube for connecting high voltage electricity, which is mounted inside the glass tube, has eight fine holes with a diameter of mm evenly distributed at the bottom. The position of the fine holes on the stainless steel tube is consistent with the assembly position of the fine holes on the glass tube, so that the gas provided by the gas distribution can enter the liquid to be treated through the stainless steel tube and the glass tube.

[0017] In the present invention, the end of the glass tube is connected to a ferrule, the gas inlet of the ferrule is connected to a gas delivery pipeline, and the other end of the gas delivery pipeline is connected to a gas tank.

[0018] Furthermore, the gas tank provides gas for the plasma reactor discharge, and a gas flow meter is connected in series on the gas delivery pipeline. It is worth mentioning that the high-voltage power supply is a bipolar microsecond pulse high-voltage power supply. When the high-voltage power supply provides pulsed high voltage electricity to the ground electrode, the power supply part changes the voltage, current and frequency parameters of the pulsed high voltage electricity to regulate the concentration of active substances generated by plasma discharge.

[0019] Furthermore, in the liquid-phase bubble induced discharge plasma water treatment device of the present invention, the gas stored in the gas bottle enters the high-pressure stainless steel tube and the quartz glass tube through the gas delivery pipeline and the air inlet, and the bipolar microsecond pulse high-voltage power supply provides pulsed high-voltage electricity to the stainless steel electrode through the high-voltage input end of the power supply. Under the condition of pulsed high-voltage electricity and gas input, a large number of bubbles generated in the liquid to be treated contained in the glass container undergo plasma discharge, and a series of plasma active species generated by the discharge come into contact with organic matter in the liquid to be treated to react, and the smaller-sized bubbles have a higher specific surface area, and the internal pressure gradually increases during the process of rising from the bottom of the liquid, which increases the solubility of the active species in the water body and greatly improves the utilization rate of the active species.

[0020] Compared with the prior art, the beneficial effects of the liquid-phase bubble induced discharge plasma oxidation water treatment device and the treatment method thereof of the present invention are embodied in the following aspects: the present invention adopts the form of liquid-phase bubble discharge to overcome the influence of solution conductivity on the plasma state. Under the condition of higher conductivity, it can not only trigger plasma discharge, but also has a better water treatment purification effect. And under the condition of reducing breakdown voltage and energy consumption, a large volume of plasma is generated in water / liquid. The plasma reaction device of the present invention has a simple structural design, is easy to operate, and has the potential for industrial scale-up application. The present invention adjusts the discharge voltage, discharge frequency and discharge current through a bipolar microsecond high-voltage pulse power supply unit to control the efficiency of generating plasma active substances; the design of the electrode structure in the device increases the yield of active substances such as hydroxyl radicals, improves the mass transfer efficiency between gas and liquid of active substances, significantly enhances the purification effect of the water treatment of the present invention and reduces energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic structural diagram of a liquid-phase bubble induced discharge plasma oxidation water treatment device involved in the present invention; Figure 2 It is a schematic diagram of the high voltage power supply structure involved in the present invention; Figure 3 for Figure 1 The enlarged structural diagram at A in the middle; Figure 4 It is a schematic diagram of the cross-sectional structure of the connection between a part of the glass tube and the stainless steel tube involved in the present invention; Figure 5 It is a schematic diagram of the cross-sectional structure of the connection between a portion of the flange plate and the glass container involved in the present invention; Figure 6 for Figure 5 The enlarged structural diagram at B in the middle; Figure 7 is a schematic diagram of the degradation of diclofenac sodium (DCF) at different discharge apertures according to the method of the present invention; Figure 8 Schematic diagram of the degradation of DCF at different pH values ​​according to the method of the present invention; Fig. 9 It is a schematic diagram of the degradation changes of DCF at different initial concentrations according to the method of the present invention; Fig.10 is a schematic diagram showing the degradation changes of DCF at different gas flow rates according to the method of the present invention; Fig.11 It is a schematic diagram of degradation changes at the aqueous solution temperature during the DCF degradation process according to the method of the present invention; Fig.12 It is a schematic diagram of the change of energy proportion under different discharge aperture conditions during DCF degradation according to the method of the present invention; Fig.13 It is a schematic diagram of the degradation change of DCF at different solution conductivities according to the method of the present invention; Fig.14 It is a schematic diagram of the change of energy proportion of DCF under different solution conductivity conditions according to the method of the present invention; Fig.15 It is a quantitative graph of the generation of hydroxyl groups (OH) in the system during the reaction according to the method of the present invention; Fig.16 It is a quantitative diagram of the generation of hydrogen peroxide and dissolved ozone in the system during the reaction according to the method of the present invention.

[0022] Explanation of the reference numerals: 1-high voltage power supply; 2-exhaust pipe; 3-plasma reactor; 4-gas distribution system; 5-DC power supply; 6-frequency generator; 7-high voltage generator; 8-high voltage output terminal; 9-ground electrode terminal; 10-processing device; 11-upper cover; 12-glass container; 121-ring groove; 13-flange plate; 131-groove; 132-slot; 133-metal ring; 134-flexible sealing glue; 135-extension ring; 14-bottom bracket; 15-stainless steel hexagonal knob; 16-pressure cover; 17-ground electrode; 18-plastic nut; 19-glass tube; 20-stainless steel tube; 201-bearing; 21-flange; 22-high voltage electrode; 23-ferrule; 24-gas delivery pipeline; 25-gas flowmeter; 26-gas tank. DETAILED DESCRIPTION

[0023] Embodiment 1: Reference Figure 1 , Figure 2 As shown, the present invention provides a liquid-phase bubble induced discharge plasma oxidation water treatment device, which includes a plasma reactor 3, and the plasma reactor 3 includes a glass container 12. The bottom end of the glass container 12 is connected to a flange plate 13, and openings are provided between the glass container 12 and the flange plate 13. A glass tube 19 is installed at the opening. A stainless steel tube 20 is sleeved inside the glass tube 19. The stainless steel tube 20 is fixed to the flange plate 13 through a flange 21, and a ferrule 23 is connected to the end of the stainless steel tube 20.

[0024] Preferably, the glass container 12 can be a high borosilicate glass container, the glass tube 19 can be a UV-transmissive quartz glass tube, and the flange plate 13, the flange 21 and the ferrule 23 are all made of polytetrafluoroethylene.

[0025] Furthermore, a removable upper cover 11 is installed on the top of the glass container 12, and the glass container 12 contains liquid to be treated, wherein a bottom bracket 14 and a stainless steel hexagonal knob 15 are also installed at the bottom of the glass container 12, and the stainless steel hexagonal knob 15 cooperates with the bottom bracket 14, and the stainless steel hexagonal knob 15 can be rotated to adjust the height of the bottom bracket 14, and the bottom bracket 14 and the stainless steel hexagonal knob 15 are assembled together to support the glass container 12.

[0026] In the present invention, the hollow stainless steel tube 20 is connected to the air inlet pipe 24 through the PTFE ferrule 23 as the air inlet part, and on the other hand, the stainless steel tube 20 is connected to the high voltage end of the high voltage power supply 1 as the high voltage electrode of the plasma reactor 3.

[0027] Furthermore, the high-voltage power supply 1 includes a DC power supply 5 for generating a DC voltage signal, a high-voltage generator 7 for converting the DC voltage signal into a pulse voltage signal, and a frequency generator 6 for controlling the frequency of the pulse signal. Preferably, the high-voltage power supply 1 is a bipolar microsecond pulse high-voltage power supply. The DC power supply 5 is connected to the high-voltage generator 7 through a wire, and the high-voltage generator 7 is connected to the frequency generator 6 through a wire. The frequency generator 6 leads to a power supply high-voltage output terminal 8 and a ground electrode terminal 9 through a high-voltage power line. The power supply high-voltage output terminal 8 is used to connect the high-voltage electrode 22 in the plasma reactor 3, and the high-voltage electrode 22 is used as the energy input port of the plasma reactor 3. In addition, the frequency generator 6 can adjust the frequency of the pulse signal, and a knob is provided on the DC power supply 5 to adjust the output voltage of the bipolar pulse high-voltage power supply 1.

[0028] In the present invention, an upper cover 11 is provided at the upper end of the glass container 12 , and a hole is opened in the upper cover 11 , in which the tail gas pipe 2 is adapted, and the output end of the tail gas pipe 2 is connected to the processing device 10 .

[0029] The processing device 10 of the present invention is provided with a potassium iodide solution for absorbing gas, and the processing device 10 is also provided with a gas outlet pipe.

[0030] Furthermore, the treatment device 10 is mainly used to absorb gases such as ozone generated by the reaction in the glass container 12, wherein the gas is input into the glass container 12 through the ferrule 23, and the gas passes through the stainless steel tube 20 with fine holes and the glass tube 19 to form a large number of bubbles in the glass container 12 filled with liquid. At the same time, the high-voltage power supply 1 provides a pulsed high voltage to the ground electrode 17 in the plasma reactor 3. Under the action of the high-voltage electric field, discharge is first triggered at the fine hole channel of the stainless steel tube 20 and the glass tube 19, and streamers are derived in the bubbles, and further develop to the surface of the bubbles to generate active substances by plasma discharge reaction, and the active substances react with organic matter in the liquid to achieve the purpose of purifying the liquid.

[0031] In the present invention, a gland 16 is provided on the top of the glass container 12, and a grounding electrode 17 is sleeved on the outer side of the glass tube 19, and the grounding electrode 17 is assembled with the gland 16 through a plastic nut 18. Preferably, the material of the gland 16 is polytetrafluoroethylene.

[0032] In the present invention, at least one fine hole is disposed at the bottom of the glass tube 19 and the bottom of the stainless steel tube 20 , and the fine hole at the bottom of the glass tube 19 and the fine hole at the bottom of the stainless steel tube 20 are both located on the same axis.

[0033] Furthermore, the glass tube 19 for isolating metal from liquid, which is mounted outside the stainless steel tube 20, has eight evenly distributed fine holes at its bottom, and the stainless steel tube 20 for connecting high voltage electricity, which is mounted inside the glass tube 19, has eight evenly distributed fine holes with a diameter of 0.1 mm at its bottom. The position of the fine holes on the stainless steel tube 20 is consistent with the assembly position of the fine holes on the glass tube 19, so that the gas provided by the gas distribution can enter the liquid to be treated through the stainless steel tube 20 and the glass tube 19.

[0034] In the present invention, the end of the glass tube 19 is connected to a ferrule 23 , the gas inlet of the ferrule 23 is connected to a gas delivery pipeline 24 , and the other end of the gas delivery pipeline 24 is connected to a gas tank 26 .

[0035] Furthermore, the gas tank 26 provides gas for the discharge of the plasma reactor 3, and a gas flow meter 25 is connected in series to the gas delivery pipeline 24. It is worth mentioning that the high-voltage power supply 1 is a bipolar pulse high-voltage power supply. When the high-voltage power supply 1 provides pulsed high voltage electricity to the ground electrode 17, the power supply part changes the voltage, current and frequency parameters of the pulsed high voltage electricity to regulate the concentration of the active substances generated by the plasma discharge.

[0036] Embodiment 2: Reference Figure 1 , Figure 5 , Figure 6 As shown, further, a metal ring 133 is connected to the upper end of the inner wall of the annular groove of the flange plate 13, and the inner wall of the metal ring 133 is set to be equal in diameter to the inner wall of the flange plate 13. A flexible sealing glue 134 is provided under the metal ring 133, and the flexible sealing glue 134 can contact the upper end of the extension ring 135 of the glass container 12.

[0037] The flange plate 13 is also provided with a groove 131, and a slot 132 is provided on the side of the groove 131. The groove 131 and the slot 132 are both used for installation with the glass container 12. At the same time, an annular groove 121 is also provided on the outer side of the glass container 12. A sealing ring is installed in the annular groove 121 to reinforce the installation with the flange plate 13.

[0038] Furthermore, the glass container 12 and the flange plate 13 can be assembled and disassembled by the metal ring 133. The metal ring 133 and the inner wall sleeve connection can improve the assembly tightness of the two. When disassembling, the flange plate 13 can be separated from the glass container 12 by only removing the metal ring 133. At the same time, the coaxiality of the glass container 12 and the flange plate 13 is ensured by using the metal ring 133 and the extension plate and other structures to avoid problems such as tilting or misalignment during assembly of the two. In addition, the glass container 12 and the flange plate 13 are connected by plugging, which is convenient for subsequent disassembly. The flexible sealing glue 134 is arranged below the metal ring 133, and the flexible sealing glue 134 is sleeved with the upper part of the glass container 12, thereby ensuring that the flange plate 13 and the glass container 12 will not get stuck during assembly and disassembly. Liquid is placed inside the glass container 12. For situations where the glass container 12 may be partially deformed or expanded due to operations such as placing liquid, inflating, and discharging inside the glass container 12, the flexible sealing glue 134 and the metal ring 133 can cope with the situation and keep it sealed at all times. When the glass container 12 and the flange plate 13 are subsequently disassembled, the glass container 12 and the flange plate 13 will not be unable to be disassembled due to local deformation of the glass container 12.

[0039] Embodiment 3: Reference Figure 7 , Figure 8 , Fig. 9 As shown, the glass tube 19 for isolating metal from liquid, which is set outside the stainless steel tube 20, is uniformly punched with eight fine holes by laser punching at a position 20 mm away from the bottom of the glass tube 19; the stainless steel tube 20, which is set inside the glass tube 19 and serves as a discharge high-voltage electrode, is uniformly punched with eight fine holes with a diameter of 1 mm at the same height as the quartz tube assembly. In order to allow the gas provided by the gas distribution system 4 to pass through the fine holes of the stainless steel tube 20 and the fine holes of the quartz tube evenly, a groove with a width of 1 mm is required at the opening position of the stainless steel tube 20 during the processing. The high-voltage electrode stainless steel tube 20 extends out of the flange 21 and is connected to the ferrule 23 for connecting the gas pipe, and is connected to the stainless steel tube 20 through a wire and is connected to the voltage output terminal 8 of the high-voltage power supply 1. In addition, the flange plate 13 used to fix the plasma discharge electrode structure, the upper and lower flange plates 13 are fixed together by nuts to support the glass container 12 and fix the plasma discharge electrode structure. In order to ensure that the liquid in the container does not leak out, an annular groove 121 needs to be left during the processing. The annular groove 121 is used to place a rubber ring to ensure that there is no leakage at the position where the plasma discharge electrode structure is inserted. The annular groove 121 is used to fix the glass container 12, thereby assembling a plasma reaction device that can hold liquid and can generate discharge.

[0040] In addition, during manufacturing, the outer diameter of the high-pressure stainless steel tube 20 electrode can be 8-12mm, preferably 10mm, and the thickness is preferably 1.0mm. The material is preferably SUS304, and the length can be selected according to the experimental needs. The device is preferably 120mm. The hole is punched at a distance of 5.0mm from the bottom of the stainless steel tube 20. The hole diameter can be selected to be 0.8-1.2mm, preferably 1.0mm, and the number of holes can be selected to be 1-10, preferably 8; the processing of the stainless steel tube 20 needs to ensure good air tightness; the outer diameter of the glass tube 19 as the medium tube can be 10-12mm, preferably 12mm, and the thickness is preferably The diameter of the hole is selected to be 1.0mm, and the material is preferably ultraviolet-transparent quartz glass. The processing of quartz glass requires annealing to relieve stress. Laser drilling is performed with a distance of 20mm from the bottom of the quartz tube as the center. The hole diameter can be selected to be 0.1mm-1.0mm, preferably 0.1mm, 0.3mm, 0.5mm and 1.0mm. The number of holes is consistent with the number of stainless steel tubes 20, preferably 8; the stainless steel tube 20 and the quartz tube are assembled together and the position of the holes is highly corresponding. In order to make the gas pass through the pores of the stainless steel tube 20 and the quartz tube evenly, a groove with a width of 1mm needs to be reserved at the opening position of the stainless steel tube 20 during the processing. In accordance with the size of the stainless steel tube 20 and the glass tube 19, the gland 16 and the flange 21 used to fix the grounding electrode and the high-voltage electrode respectively are preferably 32 mm in diameter and 12 mm in thickness. Eight screw holes with a diameter of 4.5 mm are evenly reserved at the position of the concentric circle with a diameter of 24 mm, and a groove with a depth of 1.5 mm is reserved at the concentric circle with a diameter of 15 mm to place the rubber ring to fix the electrode structure; the material of the grounding electrode is preferably SUS304, the diameter of the stainless steel ring at the upper end is preferably 32 mm, the height is 8 mm, and the middle The diameter of the central circular hole is 14mm, which is welded to the stainless steel tube 20 with a height of 8mm, and its lower end is welded to a circular ring with a height of 3mm as a grounding electrode. At the same time, eight circular holes with a diameter of 4.5mm are required to be punched with a distance of 3mm from the top of the upper stainless steel circular ring as the center, so that the bubbles bulging from the corresponding fine holes of the stainless steel tube 20 and the quartz tube are not destroyed; the circular ring welded at the lower end has eight screw holes with a diameter of 4.5mm evenly reserved at the concentric circle position with a diameter of 24mm, and is fixed together with the gland 16 by a plastic nut 18. The material of the container for holding liquid is preferably high borosilicate glass, with an outer diameter of preferably 100mm, a wall thickness of 3mm, and a length of 500mm. The glass tube 19 is embedded in the groove 131 of the flange plate 13, and a rubber ring is placed in the groove 131 to fix the container. The specification of the ferrule used to connect the air pipe is preferably 6 to 10.

[0041] Embodiment 4: Reference Fig.11 , Fig.12As shown, in the above-mentioned water treatment process, when the gas distribution system provides gas for the discharge of the stainless steel high-voltage electrode 22, the oxygen delivery flow rate can be controlled by a gas flow meter to adjust the amount of bubbles generated in the liquid. Preferably, a flow rate of 1.0 L / min is the best, which is conducive to the stable discharge of bubbles; and bubbles of different sizes can be formed by the aperture of the laser punching of the glass tube 19 to adjust the intensity of the plasma discharge and the treatment efficiency of the liquid in the container. Preferably, the treatment effect is best when the aperture of the glass tube 19 is 0.1 mm, and the plasma discharge stability is the best.

[0042] In addition, when the high-voltage power supply 1 provides pulsed high voltage electricity to the stainless steel high-voltage electrode 22, the concentration of plasma active species and its treatment efficiency for the liquid in the container can be adjusted by changing parameters such as the voltage, current and frequency of the pulsed high voltage electricity. Preferably, the treatment efficiency is optimal when the power supply input voltage is controlled to be 60.0 V, the current is 0.3 A and the pulse frequency is 3.75 kHz.

[0043] During the treatment process, samples can be taken at the water outlet of the container for subsequent test analysis.

[0044] Below, taking the example that the high-voltage electrode 22 and the grounding electrode are made of stainless steel tubes 20, the bubbling tube is made of laser-punched ultraviolet-transparent glass tubes 19, the container is made of high borosilicate material for holding liquid, the glass container 12 contains the liquid to be treated, and the gas provided by the gas distribution system is oxygen, the process of using the liquid phase bubble induced discharge plasma water treatment device to treat wastewater is briefly described: Assemble the plasma discharge reaction device; First, the reactor is ventilated, the pressure reducing valve of the gas bottle is opened, and the flow rate of oxygen is adjusted by the gas flow displayed on the gas flow meter. The liquid to be treated is placed in a glass container through the water inlet. Since the glass tube 19 has fine holes, the waste water will not enter the glass tube 19 and the stainless steel tube 20 due to the effect of gas pressure.

[0045] Then, the voltage output end of the high-voltage power supply 1 is connected to the high-pressure stainless steel pipe 20 of the plasma reactor 3 .

[0046] The high-voltage generator 7 and the DC power supply are turned on in sequence, and the input voltage and current of the power supply are changed by the knob of the DC power supply, and the pulse frequency is changed by adjusting the frequency generator 6; in the case of oxygen input, the gas passes through the pores of the stainless steel tube 20 and the glass tube 19 to form a large number of bubbles in the liquid, and the bubbles discharge under the high-voltage electric field to generate rich plasma active species, and these plasma active species come into contact with the organic matter in the wastewater to react.

[0047] During the treatment process, samples can be taken from the water outlet to test the indicators of the treated water.

[0048] During the processing, the gas flow meter, power supply input voltage, current, frequency, etc. can select the following range parameters: Gas flow adjustment range: 0.3 - 3.0 L / min; Input voltage adjustment range: 10 - 100 V; Input current adjustment range: 0.1 - 1.0 A Pulse frequency adjustment range: 0 - 20 kHz; The reference drawings are schematic diagrams of the removal rate change test of diclofenac sodium DCF using the device and method of the present invention at different quartz glass pore diameters, different initial solution pH, different initial solution concentrations and different gas flow rates; the specific experimental process is as follows.

[0049] Experiment 1 Assemble the high voltage power supply 1 and the plasma reaction device respectively; according to the purpose of the experiment, it is necessary to experiment with different apertures of the glass tube 19, which are 0.1 mm, 0.3 mm, 0.5 mm, and 1.0 mm respectively.

[0050] 0.5 L of 10 mg / L DCF solution with a pH of 6.0 was placed in the container of the reaction device through the water inlet of the reaction device; Open the pressure reducing valve of the gas bottle, introduce gas into the reaction vessel, and adjust the gas flow rate to 1.0 L / min according to the display of the gas flow meter; at the same time, connect the high-voltage output end of the power supply to the high-voltage stainless steel pipe 20, and connect the grounding stainless steel flange 21 to the grounding end of the power supply; Turn on the switches of the high voltage generator 7 and the DC power supply respectively, adjust the frequency of the frequency generator 6, fix the pulse frequency to 3.75 kHz, adjust the input voltage to 60 V, and the current to 0.3 A; After plasma discharge occurs, turn on the stopwatch and take samples at treatment times of 0, 1, 2, 3, 4, 5, 10, and 15 min, respectively.

[0051] Experiment 2 Assemble the high voltage power supply 1 and the plasma reaction device respectively, and select the aperture of the glass tube 19 to be 0.3 mm; 0.5 L, 10 mg / L DCF solutions with different initial pH values ​​were placed in the container of the reaction device through the water inlet of the reaction device; according to the purpose of the experiment, solutions with different initial pH values ​​needed to be treated, and the pH values ​​were 5, 6, 7, and 9, respectively; Open the pressure reducing valve of the gas bottle, introduce gas into the reaction vessel, and adjust the gas flow rate to 1.0 L / min according to the display of the gas flow meter; at the same time, connect the high-voltage output end of the power supply to the high-voltage stainless steel pipe 20, and connect the grounding stainless steel flange 21 to the grounding end of the power supply; Turn on the switches of the high voltage generator 7 and the DC power supply respectively, adjust the frequency of the frequency generator 6, fix the pulse frequency to 3.75 kHz, adjust the input voltage to 60 V, and the current to 0.3 A; After plasma discharge occurs, turn on the stopwatch and take samples at treatment times of 0, 1, 2, 3, 4, 5, 10, and 15 min, respectively.

[0052] Experiment 3 Assemble the high voltage power supply 1 and the plasma reaction device respectively, and select the aperture of the glass tube 19 to be 0.3 mm; 0.5 L of DCF solution with pH = 6.0 was placed in the container of the reaction device through the water inlet of the reaction device; according to the purpose of the experiment, solutions with different initial concentrations needed to be treated, and the initial concentrations were 10, 20, 40, and 80 mg / L respectively; Open the pressure reducing valve of the gas bottle, introduce gas into the reaction vessel, and adjust the gas flow rate to 1.0 L / min according to the display of the gas flow meter; at the same time, connect the high-voltage output end of the power supply to the high-voltage stainless steel pipe 20, and connect the grounding stainless steel flange 21 to the grounding end of the power supply; Turn on the switches of the high voltage generator 7 and the DC power supply respectively, adjust the frequency of the frequency generator 6, fix the pulse frequency to 3.75 kHz, adjust the input voltage to 60 V, and the current to 0.3 A; After plasma discharge occurred, a stopwatch was turned on and samples were taken at treatment times of 0, 1, 2, 3, 4, 5, 10, 15, 20, and 30 min, respectively.

[0053] Experiment 4 Assemble the high voltage power supply 1 and the plasma reaction device respectively, and select the aperture of the glass tube 19 to be 0.3 mm; 0.5 L of 10 mg / L DCF solution with a pH of 6.0 was placed in the container of the reaction device through the water inlet of the reaction device; Open the pressure reducing valve of the gas bottle and introduce gas into the reaction vessel; according to the purpose of the experiment, the solution needs to be treated at different gas flow rates, and the gas flow rates are adjusted to 0.3, 0.5, 1.0, 1.5, and 2.0 L / min respectively; at the same time, connect the high-voltage output end of the power supply to the high-voltage stainless steel pipe 20, and connect the grounding stainless steel flange 21 to the grounding end of the power supply; Turn on the switches of the high voltage generator 7 and the DC power supply respectively, adjust the frequency of the frequency generator 6, fix the pulse frequency to 3.75 kHz, adjust the input voltage to 60 V, and the current to 0.3 A; After the plasma discharge occurs, start the stopwatch and take samples at treatment times of 0, 1, 2, 3, 4, 5, 10, and 15, respectively.

[0054] Through the above experiments, it can be seen that the smaller the pore size, the higher the DCF removal rate and the faster the removal rate. The optimal treatment effect is achieved when the pore size is 0.1 mm. In an acidic environment, the removal rate of the DCF solution is faster, but after 15 minutes of treatment, whether in an acidic or alkaline environment, the plasma active substances will destroy the chemical structure of the organic matter in the DCF solution, so that the SDBS solution can eventually reach a 100% removal rate. With the increase of the initial concentration of the solution, the removal rate of DCF gradually decreases, and the degradation rate of a high-concentration solution can reach 90% or even higher after a longer treatment time. When the gas flow rate is higher than 0.3 L / min, the effect of the gas flow rate on the degradation rate of DCF dissolution is not much different.

[0055] Embodiment 5: Reference Fig.11 and attached Fig.12 As shown, in the process of treating diclofenac sodium (DCF) solution by the device and method of the present invention, the change of solution temperature due to the electrohydraulic effect and the analysis of the energy proportion in the reaction process under different pore diameters are respectively shown. The specific experimental process is as follows.

[0056] Experimental Procedure The high-voltage power supply 1 and the plasma reaction device were assembled separately. At the same time, the electrical measuring device was composed of three parts: an oscilloscope (model Lecroy WR204Xi 2 GHz, USA), a high-voltage probe (Polaris PVM-1, voltage division ratio of 2000:1), and a current transformer (Pearson 6585, voltage-current ratio of 1 V / A±1%, USA). The instantaneous values ​​of voltage and current were measured by the oscilloscope to calculate the instantaneous discharge power and discharge energy, and the energy input in the circuit was calculated based on this. The experiments were carried out under the conditions of the aperture of the glass tube 19 of 0.1 mm, 0.3 mm, 0.5 mm, and 1.0 mm respectively. 0.5 L of 10 mg / L DCF solution with a pH of 6.0 was placed in the container of the reaction device through the water inlet of the reaction device; Open the pressure reducing valve of the gas bottle, introduce gas into the reaction vessel, and adjust the gas flow rate to 1.0 L / min according to the display of the gas flow meter; at the same time, connect the high-voltage output end of the power supply to the high-voltage stainless steel pipe 20, and connect the grounding stainless steel flange 21 to the grounding end of the power supply; Turn on the switches of the high voltage generator 7 and the DC power supply respectively, adjust the frequency of the frequency generator 6, fix the pulse frequency to 3.75 kHz, adjust the input voltage to 60 V, and the current to 0.3 A; After plasma discharge occurs, turn on the stopwatch and take samples at treatment times of 0, 1, 2, 3, 4, 5, 10, 15, and 30 min respectively. After each sampling, monitor the change in water temperature through a temperature measuring device (temperature gun) to calculate the heat energy lost due to energy loss in the pulse discharge during the reaction.

[0057] From the above experiments, we can know that after 30 minutes of treatment, the water temperature of the solution rises by 6℃~7℃, so the heat energy lost is 10080J~117600J, and the energy of discharge for 30 minutes is calculated by the instantaneous values ​​of voltage and current to be 32400J. Therefore, the heat energy loss accounts for about 31.1%~36.3% of the total energy; the smaller the pore size, the higher the discharge intensity, and the rise in water temperature is basically not affected by the pore size. In this study, the energy used for bubble discharge accounts for about 22%~48%.

[0058] Embodiment 6: Reference Fig.13 and Fig.14 As shown, the changes in DCF removal rate and energy proportion analysis are respectively performed during the treatment of diclofenac sodium (DCF) solutions with different electrical conductivities using the device and method of the present invention. The specific experimental process is as follows.

[0059] Experimental Procedure The high-voltage power supply 1 and the plasma reaction device were assembled separately. At the same time, the electrical measuring device was composed of three parts: an oscilloscope (model Lecroy WR204Xi 2 GHz, USA), a high-voltage probe (Polaris PVM-1, voltage division ratio of 2000:1), and a current transformer (Pearson 6585, voltage-current ratio of 1 V / A±1%, USA). The instantaneous values ​​of voltage and current were measured by the oscilloscope to calculate the instantaneous power and energy of the discharge, and the energy input in the circuit was calculated based on this. The aperture of the glass tube 19 was selected to be 0.3 mm. 0.5 L, 10 mg / L, pH = 6.0 DCF solution was placed in the container of the reaction device through the water inlet of the reaction device; according to the purpose of the experiment, the solution needed to be treated at different conductivities, and the solution conductivity was adjusted to 0 (4.41 µs / cm), 1, 5, 10, and 20 ms / cm respectively; Open the pressure reducing valve of the gas bottle, introduce gas into the reaction vessel, and adjust the gas flow rate to 1.0 L / min according to the display of the gas flow meter; at the same time, connect the high-voltage output end of the power supply to the high-voltage stainless steel pipe 20, and connect the grounding stainless steel flange 21 to the grounding end of the power supply; Turn on the switches of the high voltage generator 7 and the DC power supply respectively, adjust the frequency of the frequency generator 6, fix the pulse frequency to 3.75 kHz, adjust the input voltage to 60 V, and the current to 0.3 A; After plasma discharge occurs, turn on the stopwatch and take samples at treatment times of 0, 1, 2, 3, 4, 5, 8, 10, 12, and 15 min. After each sampling, monitor the change in water temperature through a temperature measuring device (temperature gun) to calculate the heat energy lost due to energy loss in the pulse discharge during the reaction.

[0060] From the above experiments, we can know that the higher the conductivity of the aqueous solution, part of the energy of discharge needs to be used for the migration of ions in the solution, so the energy used for discharge is relatively reduced, and the removal rate of the solution is also reduced.

[0061] Embodiment 8: Reference Fig.15 and Fig.16 As shown, the specific experimental process of using the device and method of the present invention to quantify the active species (·OH, H2O2 and dissolved O3) produced by the reaction system is as follows.

[0062] Experiment 1 Assemble the high voltage power supply 1 and the plasma reaction device respectively; conduct experiments under the conditions where the aperture of the glass tube 19 is 0.1 mm, 0.3 mm, 0.5 mm, and 1.0 mm respectively; 0.5 L of 10 mg / L p-chlorobenzoic acid (p-CBA) solution was placed in the container of the reaction device through the water inlet of the reaction device; the hydroxyl radicals (·OH) generated by the reaction system were quantified by the degradation kinetics of p-chlorobenzoic acid; Open the pressure reducing valve of the gas bottle and introduce gas into the reaction vessel; according to the purpose of the experiment, the solution needs to be treated at different gas flow rates, and the gas flow rate is adjusted to 1.0L / min; at the same time, connect the high-voltage output end of the power supply to the high-voltage stainless steel pipe 20, and connect the grounding stainless steel flange 21 to the grounding end of the power supply; 4. Turn on the switches of the high voltage generator 7 and the DC power supply respectively, adjust the frequency of the frequency generator 6, fix the pulse frequency to 3.75 kHz, adjust the input voltage to 60 V, and the current to 0.3 A; 5. After plasma discharge occurs, turn on the stopwatch and take samples at treatment times of 0, 1, 2, 3, 5, 8, 10, 15, 20, 25, and 30 min.

[0063] Experiment 2 Assemble the high voltage power supply 1 and the plasma reaction device respectively; conduct the experiment under the condition that the aperture of the glass tube 19 is 0.3 mm; 0.5 L of ultrapure water is placed in the container of the reaction device through the water inlet of the reaction device; Open the pressure reducing valve of the gas bottle and introduce gas into the reaction vessel; adjust the gas flow rate to 1.0L / min; at the same time, connect the high-voltage output end of the power supply to the high-voltage stainless steel pipe 20, and connect the grounding stainless steel flange 21 to the grounding end of the power supply; 4. Turn on the switches of the high voltage generator 7 and the DC power supply respectively, adjust the frequency of the frequency generator 6, fix the pulse frequency to 3.75 kHz, adjust the input voltage to 60 V, and the current to 0.3 A; 5. After plasma discharge occurs, start the stopwatch and take samples at treatment times of 0, 1, 2, 3, 5, 8, 10, 15, 20, 25, and 30 min, quantify hydrogen peroxide (H2O2) by the titanium salt method, and quantify dissolved ozone in the solution by the indigo method.

[0064] The above experiments show that the smaller the discharge pore size, the higher the ·OH production, and the cumulative amount of ·OH is 1.54×108 M·min (10 min) and 4.18×108 M·min (30 min). The H2O2 content produced during the reaction basically increases linearly with the treatment time, and the dissolved ozone content in the system is low.

[0065] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A liquid phase bubble induced discharge plasma oxidation water treatment device, characterized in that: The treatment device comprises a plasma reactor (3), the plasma reactor (3) comprising a glass container (12), the bottom end of the glass container (12) being connected to a flange plate (13), an opening being provided between the glass container (12) and the flange plate (13), a glass tube (19) being installed at the opening, a stainless steel tube (20) being sleeved inside the glass tube (19), the stainless steel tube (20) being fixed to the flange plate (13) via a flange (21), and a clamping sleeve (23) being provided near the end of the stainless steel tube (20).

2. A liquid-phase bubble induced discharge plasma oxidation water treatment device according to claim 1, characterized in that: The end of the stainless steel tube (20) is also connected to an air inlet pipe (24) via a ferrule (23), and the stainless steel tube (20) is also connected to a high-voltage power supply (1).

3. The liquid-phase bubble induced discharge plasma oxidation water treatment device according to claim 1, characterized in that: An upper cover (11) is provided at the upper end of the glass container (12), and a hole is formed in the upper cover (11). An exhaust pipe (2) is adapted to be disposed in the hole, and an output end of the exhaust pipe (2) is connected to a processing device (10).

4. A liquid-phase bubble induced discharge plasma oxidation water treatment device according to claim 3, characterized in that: A potassium iodide solution for absorbing gas is arranged in the processing device (10), and a gas outlet pipe is also arranged in the processing device (10).

5. The liquid-phase bubble induced discharge plasma oxidation water treatment device according to claim 1, characterized in that: A gland (16) is provided on the top of the glass container (12), a grounding electrode (17) is sleeved on the outside of the glass tube (19), and the grounding electrode (17) is assembled with the gland (16) via a plastic nut (18).

6. A liquid-phase bubble induced discharge plasma oxidation water treatment device according to claim 5, characterized in that: The bottom of the glass tube (19) and the bottom of the stainless steel tube (20) are both provided with at least one fine hole, and the fine hole at the bottom of the glass tube (19) and the fine hole at the bottom of the stainless steel tube (20) are both located on the same axis.

7. The liquid-phase bubble induced discharge plasma oxidation water treatment device according to claim 5, characterized in that: The end of the glass tube (19) is connected to a ferrule (23), the gas inlet of the ferrule (23) is connected to a gas delivery pipeline (24), and the other end of the gas delivery pipeline (24) is connected to a gas tank (26).

8. A liquid-phase bubble-induced plasma oxidation water treatment method, characterized in that: Using a liquid-phase bubble induced discharge plasma oxidation water treatment device as described in any one of claims 1 to 7, the treatment method is as follows: Step S1: Ventilating the glass tube (19) and the stainless steel tube (20); Step S2: Power is turned on, so that bubbles generated in the glass tube (19) and the stainless steel tube (20) trigger discharge to generate a large amount of active substances, which react with the liquid in the glass container (12) to purify the liquid.

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