Ozone micro-nano bubble-electrochemistry-ceramic membrane wastewater treatment device and method

Abstract

The invention discloses an ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device and method. The device comprises a reaction container, an ozone generator and a micro-nano bubble reactor, an anode, a cathode, a microporous aeration head and a catalytic ceramic membrane are arranged in the reaction container; the anode and the cathode are connected with a direct-current power supply; a water outlet pipe is connected above the catalytic ceramic membrane; the micro-nano bubble reactor comprises a gas-liquid mixed transportation pump, an inlet of the gas-liquid mixed transportation pump is respectively connected with wastewater to be treated and an ozone outlet of the ozone generator, an outlet of the gas-liquid mixed transportation pump is connected with the microporous aeration head through a gas-liquid mixed transportation pipe, and the wastewater to be treated and ozone are mixed and fed into the reaction container. The problems that an existing sewage treatment system is low in ozone utilization rate, low in removal efficiency of suspended solids, colloidal substances and refractory organics and the like are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of deep treatment of industrial wastewater, and particularly relates to an ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device and method. Background Art

[0002] With the acceleration of industrialization, the discharge of industrial wastewater is increasing, its composition is becoming more complex, and the difficulty of treatment is increasing. Industrial wastewater, especially high-salt wastewater and organic wastewater, often contains a large amount of inorganic solid suspended matter, difficult-to-degrade organic matter and salts, which are not only highly toxic to organisms, but also pose a serious threat to the ecological environment. If it is directly discharged without effective treatment, it will cause environmental problems such as soil salinization and water eutrophication, affect the growth of animals and plants, and endanger human health.

[0003] Among the existing industrial wastewater treatment technologies, ozone oxidation has attracted widespread attention because ozone has strong oxidizing properties and can effectively decompose some organic matter. However, the traditional ozone treatment process has the problem of low ozone utilization. Ozone has limited solubility in water and is easy to decompose. A large amount of unreacted ozone is directly discharged, which not only wastes resources, but also may cause secondary pollution to the environment. At the same time, the use of ozone treatment alone is not ideal for the removal of suspended matter, colloidal substances and difficult-to-degrade organic matter.

[0004] In order to improve the oxidation efficiency of ozone and enhance the wastewater treatment effect, researchers have tried to use ozone in conjunction with other processes to treat industrial wastewater. For example, patent CN108217862A proposes a dual-electrode electrocoagulation-electrocatalytic ozone device and industrial wastewater treatment method. The cathode and anode and O3 work together to improve the oxidation efficiency of O3, effectively improving the wastewater treatment efficiency. However, the utilization efficiency of O3 in this patent is not high, and the oxidation and separation efficiency needs to be improved urgently.

[0005] Patent CN112321026A provides a wastewater treatment device and method of ozone micro-nano bubble catalytic oxidation technology coupled with ceramic membrane. The device includes an ozone generator, a micro-nano bubble generator, a catalytic oxidation reactor, a clear water tank, a tail gas treatment system and a backwashing system; the ozone generator is connected to the micro-nano bubble generator; the micro-nano bubble generator is connected to the water inlet at the bottom of the catalytic oxidation reactor; the catalytic oxidation reactor includes a reactor body and a built-in ceramic membrane assembly; the backwashing system is connected to the catalytic oxidation reactor and the clear water tank respectively; the tail gas treatment system is connected to the exhaust port of the catalytic oxidation reactor. However, this method has failed to effectively improve the utilization rate of ozone, and there is still room for improvement in oxidation and separation efficiency. In addition, there is still a lot of room for improvement in oxidation and separation efficiency, and it is difficult to meet the increasingly stringent environmental protection standards for industrial wastewater treatment.

[0006] In addition, existing wastewater treatment equipment is often complex in structure, cumbersome to operate, and has high operating costs. Some treatment processes require the addition of large amounts of chemicals, which not only increases treatment costs but may also generate new pollutants. In terms of floor space, traditional treatment equipment is usually large in size, which is undoubtedly a heavy burden for areas with limited land resources.

[0007] In summary, it is urgent to develop a water treatment device and method that can improve ozone utilization, efficiently remove suspended solids, colloidal substances and difficult-to-degrade organic matter, and is easy to operate and low-cost. This will not only help solve the current difficulties faced by industrial wastewater treatment and promote sustainable industrial development, but also effectively protect the ecological environment, which has important practical significance. Summary of the invention

[0008] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide an ozone micro-nano bubble coupled electrochemistry and catalytic ceramic membrane integrated water treatment device and method, which is mainly used to solve the problems of low ozone utilization and low removal efficiency of difficult-to-degrade organic matter in existing sewage treatment systems.

[0009] In order to achieve the above object, the technical solution adopted by the present invention is:

[0010] On the one hand, an ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device is provided, characterized in that it includes a reaction container 1, an ozone generator 7, a microporous aeration head 3, a micro-nano bubble reactor 16 and a catalytic ceramic membrane 29; the reaction container 1 has an anode 2, a cathode 4, a microporous aeration head 3 and a catalytic ceramic membrane 29 built in; the anode 2 and the cathode 4 are connected to a DC power supply 5; the catalytic ceramic membrane 29 is connected to a water outlet pipe 24 above;

[0011] The micro-nano bubble reactor 16 includes a gas-liquid mixed delivery pump 17, the inlet of which is respectively connected to the wastewater pipeline to be treated and the ozone outlet of the ozone generator 7 to achieve efficient mixing of wastewater and ozone. The outlet of the gas-liquid mixed delivery pump 17 is connected to the microporous aeration head 3 through a gas-liquid mixed delivery pipe 10 to mix the wastewater to be treated with ozone and send it into the reaction container 1.

[0012] Furthermore, the material of the anode 2 is one or more of aluminum, PbO2, tin-antimony alloy, and ruthenium-iridium alloy, and the material of the cathode 4 is one or more of carbon black polytetrafluoroethylene, foamed titanium, foamed nickel, and foamed copper.

[0013] Furthermore, the catalytic ceramic membrane 29 is arranged above the anode 2 and the cathode 4 , the microporous aeration head 3 is arranged below the anode 2 and the cathode 4 , the anode 2 and the cathode 4 are vertically spaced apart and penetrate a plurality of horizontal isolation columns 14 .

[0014] Furthermore, the reaction container 1 is connected to a liquid level meter 15, and a water pipe valve 28 is provided on the gas-liquid mixed transmission pipe 10. The liquid level meter 15 is used to monitor the liquid volume in the reaction container 1 to ensure that the catalytic ceramic membrane 29, the anode 2, the cathode 4 and the microporous aeration head 3 are immersed in the wastewater to be treated.

[0015] Furthermore, the ozone outlet of the ozone generator 7 is connected to the inlet of the gas-liquid mixed delivery pump 17 through a gas pipe 21 with a three-way valve 22, and the suspended port of the three-way valve 22 is connected to an ozone gas concentration analyzer 6 with an ozone tail gas destroyer 23, and the ozone gas concentration analyzer 6 is used to monitor the ozone gas concentration output by the ozone generator 7.

[0016] Furthermore, the micro-nano bubble reactor 16 generates bubbles with a diameter between 100 nm and 50 μm; the pore diameter of the microporous aeration head 3 is 1-3 mm.

[0017] Furthermore, the wastewater to be treated is connected to the inlet of the gas-liquid mixed transfer pump 17 through a water pipe 18 with a water inlet valve 30, a water inlet pump 19 and a flow meter 20; the flow meter 20 is used to control the liquid flow entering the reaction container 1.

[0018] The present invention also provides a wastewater treatment method, which is implemented based on the above-mentioned ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device, and includes the following steps:

[0019] Step 1, turn on the micro-nano bubble generator 16, pump the wastewater to be treated into the reaction container 1 through the gas-liquid mixed pump 17, so that the anode 2, the cathode 4, the microporous aeration head 3 and the catalytic ceramic membrane 29 are all immersed in the wastewater to be treated;

[0020] Step 2, turning on the ozone generator 7 to generate ozone, mixing the wastewater to be treated with the ozone through the gas-liquid mixing pump 17, and then passing the wastewater into the reaction container 1 through the microporous aeration head 3;

[0021] Step 3, turn on the DC power supply 5, generate flocculant through the anode 2, aggregate and adsorb pollutants in the wastewater to be treated to form flocs, reduce dissolved oxygen through the cathode 4 to generate hydrogen peroxide, react with ozone and flocculant to generate hydroxyl radicals, and completely mineralize organic pollutants into carbon dioxide and water, and further remove colloids and difficult-to-degrade organic matter through the action of catalytic ceramic membrane 29 and ozone, and further enhance the removal of organic matter.

[0022] Step 4: After the wastewater treatment is completed, the water is discharged through the effluent pump 25, and the flocs are collected and discharged at the bottom of the reaction container 1.

[0023] Furthermore, the concentration of the added gaseous ozone is 5-100 mg / L, the flow rate of ozone is 0.1-1 L / min, and the current of the DC power supply 5 after powering on is 5-600 mA / cm 2 , the residence time of the wastewater to be treated is 15 to 120 minutes.

[0024] Furthermore, the wastewater to be treated is industrial wastewater.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The industrial wastewater treatment method of the present invention causes O3 micro-nano bubbles to react with the electrochemical cathode to produce E-Peroxone and anode flocculation reactions, and to combine with catalytic ceramic membrane water to produce ·OH by in-situ catalytic oxidation. While gradually mineralizing and degrading the difficult-to-degrade organic pollutants in the wastewater, it can effectively flocculate and remove organic matter and suspended matter in the wastewater. The three have a synergistic effect, and the membrane system can fully utilize the aeration and oxidation effects in the system to reduce membrane pollution, greatly improve the COD (chemical oxygen demand) removal efficiency, save floor space, and achieve the synergy of the cathode, anode and O3 micro-nano bubbles and the catalytic ceramic membrane.

[0027] 2. The device provided by the present invention adopts dual electrodes of cathode and anode at the same time, and the H2O2 generated in the wastewater is continuously generated in situ, which greatly reduces the operating cost while improving safety, and can effectively improve the utilization rate of electric energy. At the same time, the setting of the microporous aeration head can enhance the liquid phase mass transfer of difficult-to-degrade organic matter, H2O2 and ·OH, thereby enhancing the current efficiency.

[0028] 3. The device provided by the present invention is simple to operate and easy to control. The device can be controlled by adjusting the water flow rate of the water pump and the concentration of the ozone generator, thereby achieving the treatment of organic wastewater with no or a small amount of reagent addition and efficient use of O3.

[0029] 4. The device and method provided by the present invention are generally applicable to wastewater from different sources, have good application prospects, and can be widely used in the field of deep wastewater treatment, especially in the technical field of deep industrial wastewater treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device in the present invention.

[0031] Figure 2 It is a comparison chart of COD removal efficiency of three treatment methods in the embodiments of the present invention.

[0032] Description of Figure Numbers:

[0033] 1. Reaction vessel; 2. Anode; 3. Microporous aeration head; 4. Cathode; 5. DC power supply; 6. Ozone gas concentration analyzer; 7. Ozone generator; 8. Cathode conductive rod; 9. Anode conductive rod; 10. Gas-liquid mixed transmission pipe; 11. Arc capping; 12. Valve; 13. Ozone destroyer; 14. Isolation column; 15. Liquid level meter; 16. Micro-nano bubble reactor; 17. Gas-liquid mixed transmission pump; 18. Water pipe; 19. Water inlet pump; 20. Flow meter; 21. Gas pipe; 22. Three-way valve; 23. Ozone tail gas destroyer; 24. Water outlet pipe; 25. Water outlet pump; 26. Sludge collection tank; 27. Gas outlet pipe; 28. Water pipe valve; 29. ​​Catalytic ceramic membrane; 30. Water inlet valve. DETAILED DESCRIPTION

[0034] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0035] It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or collections.

[0036] In order to simplify the drawings, only the parts related to the present invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0037] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0038] In the embodiments shown in the drawings, the indications of directions (such as up, down, left, right, front and back) used to explain the structure and movement of the various components of the present invention are not absolute but relative. These descriptions are appropriate when these components are in the positions shown in the drawings. If the descriptions of the positions of these components change, the indications of these directions also change accordingly.

[0039] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0040] The present invention provides an ozone micro-nano bubble coupled electrochemistry and catalytic ceramic membrane integrated water treatment device and method, which are used to improve the ozone utilization efficiency and achieve the coordinated removal of suspended solids, colloidal substances and difficult-to-degrade organic matter in wastewater. Specifically, the present invention uses ozone micro-nano bubbles to improve the utilization rate of ozone in the system and the mass transfer efficiency of the system, and further utilizes micro-nano bubbles in combination with ozone catalytic cathode to produce H2O2 and catalytic ceramic membrane, giving full play to the electrocatalytic oxidation and catalytic oxidation of ozone to produce free radicals to enhance oxidation, and synergistically utilizes ozone through micro-nano bubbles and catalytic ceramic membranes, and reduces membrane pollution, further improving the efficiency of the system. At the same time, the removal of organic matter or colloidal particles can also be further enhanced by optimizing the anode and combining the anode with the flocs produced by the oxidation or flocculation process of the anode.

[0041] Specific as Figure 1 As shown, the ozone micro-nano bubble coupled electrochemical and catalytic ceramic membrane integrated water treatment device provided by the present invention mainly includes three parts: a reaction container 1, an ozone generator 7 and a micro-nano bubble reactor 16. Among them, the reaction container 1 is equipped with an anode 2, a cathode 4, a microporous aeration head 3 and a catalytic ceramic membrane 29, the anode 2 and the cathode 4 are connected to a DC power supply 5, and the top of the catalytic ceramic membrane 29 is connected to a water outlet pipe 24. The micro-nano bubble reactor 16 includes a gas-liquid mixed delivery pump 17, the inlet of the gas-liquid mixed delivery pump 17 receives the wastewater to be treated and the ozone outlet of the ozone generator 7 respectively, and the outlet of the gas-liquid mixed delivery pump 17 is connected to the microporous aeration head 3 through a gas-liquid mixed delivery pipe 10, and the wastewater to be treated is mixed with the ozone generated by the ozone generator 7 and sent to the reaction container 1 through the microporous aeration head 3.

[0042] According to the above structure, the present invention mixes ozone with the wastewater to be treated in the form of micro-nano bubbles. The ozone can simultaneously react with the electrochemical cathode to produce E-Peroxone, react with the anode to produce flocculation, and combine with the catalytic ceramic membrane water to produce ·OH by in-situ catalytic oxidation. It can not only gradually mineralize and degrade the difficult-to-degrade organic pollutants in the wastewater, but also flocculate and remove organic matter and suspended matter in the wastewater, thereby synergistically improving the wastewater treatment effect and efficiency.

[0043] Therefore, the present invention can generate flocs and hydroxyl radicals with strong oxidizing properties in situ during the process of treating wastewater to achieve efficient removal of colloids and organic matter in wastewater, and further utilize micro-nano bubbles in combination with ozone catalytic cathode to produce H2O2 and catalytic ceramic membrane, give full play to the electrocatalytic oxidation and catalytic oxidation of ozone to produce free radicals to strengthen oxidation, and use ozone synergistically through micro-nano bubbles and catalytic ceramic membranes, and reduce membrane pollution, thereby further improving the efficiency of the system. At the same time, the removal of organic matter or colloidal particles can also be further enhanced by optimizing the anode, combining the anode with the flocs generated by the flocculation of aluminum or iron anodes or PbO2 or tin antimony or ruthenium iridium anode oxidation. Then, the coupling of micro-nano bubbles with electrochemical oxidation and catalytic ceramic membrane systems is achieved (greatly improving the system efficiency and treatment efficiency. The present invention is simple to operate, easy to control, has good application prospects, and can be widely used in the field of wastewater treatment technology.

[0044] In the embodiment of the present invention, the reaction vessel 1 adopts a cylindrical structure with an arc-shaped capping 11 and a sludge collection tank 26. Specifically, the top of the reaction vessel 1 is provided with an arc-shaped capping 11, and the bottom is provided with a chamfered sludge collection tank 26. The arc-shaped capping 11 is connected to the outlet pipe 27, and an ozone destroyer 13 can be provided at the end of the outlet pipe 27. The bottom of the sludge collection tank 26 is connected to the external sludge discharge pipe through a valve 12. The anode 2, the microporous aeration head 3, the cathode 4 and the catalytic ceramic membrane 29 are arranged in the reaction vessel 1, wherein the material of the anode 2 can be aluminum or PbO2 or tin antimony or ruthenium iridium, etc., and the material of the cathode 4 can be carbon black polytetrafluoroethylene or foamed titanium or foamed nickel or foamed copper, etc. The catalytic ceramic membrane 29 is arranged above the anode 2 and the cathode 4, and the microporous aeration head 3 is arranged below the anode 2 and the cathode 4, so that the wastewater to be treated first undergoes an electrochemical reaction and then enters the catalytic ceramic membrane 29 area for membrane treatment. The current after the DC power supply 5 is 5-600mA / cm 2 , more preferably 5-20mA / cm 2 , the residence time of the wastewater to be treated is 15 to 120 minutes, more preferably 15 minutes. In order to achieve installation and fixation and improve the electrochemical reaction effect, the present invention has multiple anodes 2 and cathodes 4, which are arranged vertically in sequence and penetrate several horizontal isolation columns 14. The microporous aeration head 3 is connected to the micro-nano bubble generator 16 through the gas-liquid mixed transmission pipe 10, specifically connected to the outlet of the gas-liquid mixed transmission pump 17, and the catalytic ceramic membrane 29 is connected to the outlet water pump 25 through the outlet pipe 24.

[0045] The electrode group composed of the anode 2 and the cathode 4 of the present invention adopts a monopolar connection method, that is, a single wire is used to connect to multiple devices in the circuit. In terms of the connection between the electrode group and the power supply, the negative pole of the power supply is connected to the cathode 4 via the cathode conductive rod 8, and the positive pole of the power supply is connected to the anode 2 via the anode conductive rod 9.

[0046] Furthermore, the reaction vessel 1 of the present invention is connected to a liquid level meter 15, and a water pipe valve 28 is provided on the gas-liquid mixed transmission pipe 10. The liquid level meter 15 is used to monitor the liquid volume in the reaction vessel 1 to ensure that the catalytic ceramic membrane 29, the anode 2, the cathode 4 and the microporous aeration head 3 are all immersed in the wastewater to be treated during treatment.

[0047] In an embodiment of the present invention, the micro-nano bubble generator 16 mainly includes a gas-liquid mixed delivery pump 17, which can generate bubbles with a diameter between 100nm-50μm. Specifically, the micro-nano bubble generator 16 also includes a shell, a separation tank, a distribution box, a plurality of releasers, a vacuum meter, a gas flow meter, a plurality of button switches, a circuit breaker, a plurality of contactors, an overload protection device, a contactor, a plurality of regulating valves, a process pipeline, an inlet and outlet water pipe, etc. The micro-nano bubble of the present invention refers to a bubble with a diameter between tens of micrometers and hundreds of nanometers when the bubble occurs, and has the characteristics of large specific surface area, slow floating speed, high mass transfer efficiency, surface charge, and generation of a large number of hydroxyl free radicals. The micro-nano bubble reactor generates bubbles by high-pressure dissolution and reduced-pressure release, that is, the high pressure causes the mixed gas to be saturatedly dissolved in water, and then the reduced-pressure release gas is released, thereby generating micro-nano bubbles. It can stably inject high-pressure gas into the liquid at a small flow rate, and at the same time, through an efficient mixing device (in the present invention, a gas-liquid mixing pump 17), ensure the uniform distribution of bubbles in the liquid, so that the bubbles have a larger contact area with the substances in the liquid, and enhance the stability and activity of the bubbles. Finally, the wastewater to be treated mixed with gas is input from the microporous aeration head 3 to the reaction container 1 through the gas-liquid mixing pipe 10, wherein the micropores of the microporous aeration head 3 are arranged (the pore diameter is between 1-3mm), so that the ozone mixed wastewater to be treated in the form of micro-nano bubbles can be uniformly overflowed in the reaction container 1 through the multiple micropores thereon, so that the micro-nano bubbles are fully in contact with the wastewater to be treated.

[0048] In an embodiment of the present invention, the gas inlet of the gas-liquid mixed delivery pump 17 is connected to the ozone outlet of the ozone generator 7 through the gas delivery pipe 21 through one end of the three-way valve 22. The three-way valve 22 has a suspended port, which is connected to the ozone gas concentration analyzer 6 with an ozone tail gas destroyer 23. Through the ozone gas concentration analyzer 6, the ozone gas concentration output by the ozone generator 7 can be monitored to monitor and cooperate with the valve to control the concentration of ozone in the water treatment process and monitor and adjust in time. Generally, the concentration of the gas phase ozone added can be controlled to be 5-100 mg / L, and more preferably 7-10 mg / L. Here, the concentration refers to the ozone gas concentration detected by the ozone gas concentration analyzer 6 when the ozone generator 7 outputs it, specifically the number of milligrams of ozone per liter of gas (the main components are O3 and O2), and the flow rate of ozone is 0.1-1 L / min. The ozone tail gas destroyer 23 can destroy the sampled ozone used to detect the concentration and then discharge it to avoid polluting the air.

[0049] The liquid inlet of the gas-liquid mixed transfer pump 17 is connected to the wastewater to be treated through a water pipe 18 with an inlet valve 30, an inlet pump 19 and a flow meter 20. The flow meter 20 is used to monitor and cooperate with the valve to control the liquid flow from the inlet pump 19 into the reaction vessel 1 to ensure the regulation of the amount of industrial wastewater to be treated in the water treatment process.

[0050] Based on the above device, the present invention provides a wastewater treatment method, comprising the following steps:

[0051] 1) Open the water inlet valve 30, the water inlet pump 19 and the micro-nano bubble reactor 16, and inject the wastewater to be treated into the reaction container 1 through the gas-liquid mixed delivery pump 17 directly or after mixing with air, through the gas-liquid mixed delivery pipe 10 and the microporous aeration head 3, so that the anode 2, the cathode 4, the microporous aeration head 3 and the catalytic ceramic membrane 29 are immersed, and the liquid flow rate is controlled by the flow meter 20 during the process.

[0052] 2) Turn on the ozone generator 7 to generate ozone, introduce ozone gas into the micro-nano bubble reactor 16 through the gas pipe 21, mix it with the wastewater to be treated through the gas-liquid mixing pump 17, and then input the gas-liquid mixture of ozone micro-nano bubbles and wastewater into the reaction container 1 through the gas-liquid mixing pipe 10 through the microporous aeration head 3. The concentration of ozone introduced into the container can be controlled by the ozone solubility analyzer 6.

[0053] 3) Turn on the DC power supply 5, connect the negative pole of the power supply to the cathode 4 via the cathode conductive rod 8, and connect the positive pole of the power supply to the anode 2 via the anode conductive rod 9. The wastewater is treated through the anode 2, the cathode 4, the introduced ozone gas, and the catalytic ceramic membrane 29 placed above the inside of the reaction container 1. Specifically, the anode 2 produces a hydroxyl complex as a flocculant to aggregate and adsorb pollutants in the wastewater to be treated to form flocs; the surface of the cathode 4 reduces the dissolved oxygen to generate hydrogen peroxide, and the obtained hydrogen peroxide further reacts with the flocculant and the introduced ozone to generate ·OH with strong oxidizing properties in the wastewater to be treated, which can quickly oxidize the organic pollutants in the wastewater to be treated and completely mineralize the organic pollutants into harmless CO2 and H2O. The catalytic ceramic membrane 29 further oxidizes the residual organic matter and removes the colloid and particulate matter.

[0054] 4) After the wastewater is treated by the catalytic ceramic membrane 29, it is pumped out through the outlet pipe 24 via the outlet pump 25. The valve 12 is opened to discharge the flocs settled in the sludge collection tank 26 out of the reaction vessel 1 through the sludge discharge pipe.

[0055] Detailed experimental settings and effect comparisons were carried out for the three treatment methods of single ozone micro-nano bubbles, ozone micro-nano bubbles coupled electrochemistry, and ozone micro-nano bubbles coupled electrochemistry and ceramic membranes when treating RO concentrated water, so as to highlight the treatment differences of RO concentrated water by different treatment methods, thereby verifying the advantages of the coupled treatment method in the present invention in improving the efficiency of industrial wastewater treatment.

[0056] Example 1: Treatment of RO Concentrated Water with Ozone Micro-Nano Bubbles Alone

[0057] In this embodiment, in order to explore the treatment effect of ozone micro-nano bubbles on RO concentrated water alone, the following experimental operations were performed. RO concentrated water was added to the reaction vessel 1 in the present invention. After testing, the initial value of the chemical oxygen demand (COD) of the RO concentrated water was 85 mg / L. The ozone micro-nano bubble generator was turned on, the concentration of the ozone introduced was controlled to be stable at 60 mg / L, and the gas flow rate was set to 0.4 L / min. Carbon black-PTFE was used as the cathode and Al plate was used as the anode, but in this embodiment, only ozone micro-nano bubbles were used to treat RO concentrated water, electrochemical related operations were not turned on, and catalytic ceramic membranes were not used. The treatment process lasted for 60 minutes, during which the effluent continued to flow back to the reactor to ensure the stability and continuity of the treatment process. After the treatment, the COD concentrations of the inlet and outlet water were measured respectively, and the COD removal rate was calculated according to the formula. After rigorous measurement and calculation, the treatment efficiency of ozone micro-nano bubbles alone for RO concentrated water was 38.88%.

[0058] Example 2: Ozone micro-nano bubble coupling electrochemical treatment of RO concentrated water

[0059] This embodiment focuses on the treatment of RO concentrated water by ozone micro-nano bubbles coupled with electrochemistry. RO concentrated water with an initial COD value of 85 mg / L is added to the reaction vessel 1 of the present invention. The ozone micro-nano bubble generator is turned on, the concentration of the ozone introduced is controlled at 60 mg / L, the gas flow rate is maintained at 0.4 L / min, carbon black-PTFE is used as the cathode, and Al plate is used as the anode. Unlike Example 1, the electrochemical operation is turned on in this embodiment, a DC power supply is connected, and a catalytic ceramic membrane is not used. The treatment time is set to 60 minutes, and the effluent continues to flow back to the reactor during the treatment. After the treatment, the COD concentrations of the inlet and outlet water are carefully measured and the removal rate is calculated. Finally, it was found that the treatment efficiency of RO concentrated water by ozone micro-nano bubbles coupled with electrochemistry was 59.38%.

[0060] Example 3: Ozone micro-nano bubbles coupled with electrochemistry and ceramic membrane to treat RO concentrated water

[0061] In this embodiment, the treatment effect of ozone micro-nano bubbles coupled with electrochemistry and ceramic membrane on RO concentrated water is studied in detail. RO concentrated water with an initial COD of 85 mg / L is added to the reaction vessel 1 in the present invention. The ozone micro-nano bubble generator is turned on to stabilize the ozone concentration at 60 mg / L, the gas flow rate is 0.4 L / min, carbon black-PTFE is used as the cathode, Al plate is used as the anode, a DC power supply is enabled for electrochemical operation, and a catalytic ceramic membrane is used. The treatment time is 60 minutes, and the effluent continues to reflux during the treatment process. After the treatment is completed, the COD concentration of the inlet and outlet water is accurately measured and the removal rate is calculated. After measurement and calculation, the treatment efficiency of RO concentrated water by ozone micro-nano bubbles coupled with electrochemistry and ceramic membrane reached 67.44%.

[0062] Figure 2 This is a schematic diagram comparing the treatment effects of the three treatment methods in the embodiments of the present invention. From the results in the figure, we can see that the treatment efficiency in embodiment 3 is the highest, reaching 67.44%, and can more efficiently remove organic matter, suspended matter, colloids and refractory organic matter in wastewater. The synergistic effect of the catalytic ceramic membrane and ozone further enhances the removal of organic matter, and the membrane system can make full use of the aeration and oxidation in the system to reduce membrane pollution.

[0063] The embodiments described above are part of the embodiments of the present invention, rather than all of the embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Claims

1. An ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device, characterized in that: The invention comprises a reaction container (1), an ozone generator (7), a microporous aeration head (3), a micro-nano bubble reactor (16) and a catalytic ceramic membrane (29); the reaction container (1) is equipped with an anode (2), a cathode (4), a microporous aeration head (3) and a catalytic ceramic membrane (29); the anode (2) and the cathode (4) are connected to a direct current power supply (5); and the top of the catalytic ceramic membrane (29) is connected to a water outlet pipe (24); The micro-nano bubble reactor (16) comprises a gas-liquid mixed delivery pump (17), the inlet of which is respectively connected to a wastewater pipeline to be treated and an ozone outlet of the ozone generator (7), so as to achieve efficient mixing of wastewater and ozone; the outlet of the gas-liquid mixed delivery pump (17) is connected to the microporous aeration head (3) via a gas-liquid mixed delivery pipe (10), so as to mix the wastewater to be treated with ozone and deliver it into the reaction container (1).

2. The ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device according to claim 1 is characterized in that: The material of the anode (2) is one or more of aluminum, PbO2, tin-antimony alloy, and ruthenium-iridium alloy, and the material of the cathode (4) is one or more of carbon black polytetrafluoroethylene, foamed titanium, foamed nickel, and foamed copper.

3. The ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device according to claim 1 is characterized in that: The catalytic ceramic membrane (29) is arranged above the anode (2) and the cathode (4), and the microporous aeration head (3) is arranged below the anode (2) and the cathode (4). The anode (2) and the cathode (4) are arranged vertically spaced apart and penetrate a plurality of horizontal isolation columns (14).

4. The ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device according to claim 1 is characterized in that: The reaction container (1) is connected to a liquid level meter (15), and the gas-liquid mixed transmission pipe (10) is provided with a water pipe valve (28). The liquid level meter (15) is used to monitor the liquid volume in the reaction container (1) to ensure that the catalytic ceramic membrane (29), the anode (2), the cathode (4) and the microporous aeration head (3) are immersed in the wastewater to be treated.

5. The ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device according to claim 1, characterized in that: The ozone outlet of the ozone generator (7) is connected to the inlet of the gas-liquid mixed delivery pump (17) through a gas delivery pipe (21) with a three-way valve (22), and the suspended port of the three-way valve (22) is connected to an ozone gas concentration analyzer (6) with an ozone tail gas destructor (23), and the ozone gas concentration analyzer (6) is used to monitor the ozone gas concentration output by the ozone generator (7).

6. The ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device according to claim 1, characterized in that: The micro-nano bubble reactor (16) generates bubbles with a diameter between 100 nm and 50 μm; the pore diameter of the microporous aeration head (3) is 1-3 mm.

7. The ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device according to claim 1, characterized in that: The wastewater to be treated is connected to the inlet of the gas-liquid mixed transfer pump (17) through a water delivery pipe (18) having a water inlet valve (30), a water inlet pump (19) and a flow meter (20); the flow meter (20) is used to control the flow of liquid entering the reaction container (1).

8. A wastewater treatment method, implemented based on the ozone micro-nano bubble-electrochemical-ceramic membrane wastewater treatment device according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1, turning on the micro-nano bubble generator (16), pumping the wastewater to be treated into the reaction container (1) through the gas-liquid mixed pump (17), so that the anode (2), the cathode (4), the microporous aeration head (3) and the catalytic ceramic membrane (29) are all immersed in the wastewater to be treated; Step 2, turning on the ozone generator (7) to generate ozone, mixing the wastewater to be treated with the ozone through a gas-liquid mixing pump (17), and then passing the mixture into the reaction container (1) through a microporous aeration head (3); Step 3, turning on the DC power supply (5), generating a flocculant through the anode (2), aggregating and adsorbing pollutants in the wastewater to be treated to form flocs, reducing dissolved oxygen through the cathode (4) to generate hydrogen peroxide, reacting with ozone and the flocculant to generate hydroxyl radicals, completely mineralizing organic pollutants into carbon dioxide and water, and further removing colloids and difficult-to-degrade organic matter through the action of the catalytic ceramic membrane (29) and ozone, and further enhancing the removal of organic matter. Step 4: After the wastewater treatment is completed, the water is discharged through the outlet pump (25), and the flocs are collected and discharged at the bottom of the reaction container (1).

9. A wastewater treatment method according to claim 8, characterized in that: The concentration of the added gaseous ozone is 5-100 mg / L, the flow rate of ozone is 0.1-1 L / min, and the current of the DC power supply (5) after powering on is 5-600 mA / cm 2 , the residence time of the wastewater to be treated is 15 to 120 minutes.

10. A wastewater treatment method according to claim 8, characterized in that: The wastewater to be treated is industrial wastewater.

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