Internal circulation rotating impinging stream electro-catalysis device and method for treating organic wastewater

Abstract

The invention discloses an internal circulation rotating impinging stream electro-catalysis device and method for treating organic wastewater, and belongs to the technical field of sewage treatment equipment. The upper part of an inner cavity of an electrochemical reactor of the device is an electrochemical reaction area, and the lower part is a rotational flow generation area; the electrochemical reaction area comprises an outer ring anode, an annular net-shaped cathode, an inner ring anode and a central fixing shaft which are sequentially and coaxially sleeved from outside to inside, and the rotational flow generation area comprises an inner spiral generator and an outer spiral generator which are arranged on a spiral central shaft in a sleeving manner. The impinging stream technology and the electro-catalysis technology are combined, internal circulation impinging stream efficient treatment on organic wastewater is achieved through the rotational flow generation area, the device has the advantages of being high in treatment efficiency, small in occupied space, low in operation energy consumption and the like, the problem that bubbles adhere to the surface of an electrode can be solved, strong turbulent flow is formed through impinging, reaction dead zones are reduced, and the service life of the device is prolonged. Mass transfer in the electrochemical degradation device is enhanced, and the purposes of automatic operation and efficient degradation are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment equipment, and in particular relates to an internal circulation rotating impact current electrocatalytic device and method for treating organic wastewater. Background Art

[0002] Industrial wastewater often has complex composition, poor biodegradability, and is prone to inhibit the growth of microorganisms, so it is difficult to treat using conventional biochemical methods.

[0003] In the past few decades, electrochemical technology has become a solution to many environmental problems due to its versatility, high efficiency, cost-effectiveness, automation and easy cleaning. The advantage of electrochemical oxidation technology in treating organic wastewater is that the electrons that drive the electrochemical process are the cheapest and most readily available redox agents, so no additional reagents need to be added during the oxidation process, which greatly reduces the possibility of secondary pollution and highlights its good environmental compatibility.

[0004] However, the flow field distribution inside the electrochemical reactor is not uniform, and the turbulence is weak, which is not conducive to the oxidation and degradation of pollutants. In addition, the mass transfer efficiency and conductivity of the electrode surface are low, resulting in low current efficiency and high energy consumption in the electrochemical process. At the same time, the problem of bubble curtains generated by oxygen and hydrogen evolution reactions gathering on the electrode surface during the reaction process is difficult to be effectively solved. Targeted design of a reasonable reactor is one of the important ways to improve the current efficiency of the electrochemical reaction process, reduce costs and solve the problem of bubble aggregation. Therefore, how to design a new electrochemical reactor to achieve efficient mass transfer, reduce reaction dead zones, and eliminate bubble attachment on the electrode surface is the key to the application of electrochemical technology in actual complex industrial wastewater. Summary of the invention

[0005] The purpose of the present invention is to solve the problems of low wastewater degradation efficiency caused by the adhesion of bubbles on the electrode surface and low mass transfer efficiency in the equipment in the existing electrochemical degradation equipment, and to provide an internal circulation rotating impinging flow electrocatalytic device and method for treating organic wastewater. The present invention is aimed at high-concentration organic wastewater, combines the impinging flow technology with the electrocatalytic technology, and uses a cyclone generating device to realize the internal circulation impinging flow, which has the advantages of high treatment efficiency, small footprint, low operating energy consumption, etc., can solve the problem of bubble adhesion on the electrode surface, and form strong turbulence through impact, reduce the reaction dead zone, and strengthen the mass transfer in the electrochemical degradation device, so as to achieve the purpose of automatic operation and efficient degradation.

[0006] The specific technical solutions adopted by the present invention are as follows:

[0007] In a first aspect, the present invention provides an internal circulation rotating impinging flow electrocatalytic device for treating organic wastewater, comprising an electrochemical reactor, an inlet liquid storage tank, an outlet liquid storage tank, a water quality monitoring device, a power supply device and a gas storage tank;

[0008] The electrochemical reactor is a columnar structure with a closed inner cavity, the upper part of the inner cavity is an electrochemical reaction zone, and the lower part is a vortex generating zone; the electrochemical reaction zone includes an outer ring anode, an annular mesh cathode, an inner ring anode and a central fixed axis which are coaxially sleeved in sequence from the outside to the inside, the annular area between the outer ring anode and the mesh cathode constitutes an outer reaction zone, the annular area between the mesh cathode and the inner ring anode constitutes an inner reaction zone, and the outer reaction zone and the inner reaction zone are connected above and below; the outer ring anode, the annular mesh cathode and the inner ring anode are all connected to the power supply device in a separately controlled manner;

[0009] The swirl generating area includes an inner spiral generator and an outer spiral generator sleeved on a spiral central shaft, and the spiral central shaft is coaxially connected to the lower part of the central fixed shaft; the inner spiral generator is located below the inner reaction area, and the outer spiral generator is located below the outer reaction area, and the inner spiral generator and the outer spiral generator are respectively connected to the central spiral shaft through spiral gears; the spiral central shaft is driven to rotate by a driving device, which can drive the two spiral gears to rotate in the opposite direction, so that the blades of the inner spiral generator and the outer spiral generator stir the water flow in the inner reaction area and the outer reaction area in a coaxial reverse spiral manner to present a reverse swirl;

[0010] An automatic exhaust valve connected to the electrochemical reaction zone is provided on the top of the electrochemical reactor, and the automatic exhaust valve is connected to an external gas storage tank through a pipeline; the online monitoring probe of the water quality monitoring device extends below the liquid surface of the electrochemical reaction zone; a water inlet and outlet are provided on the side wall of the electrochemical reactor located in the vortex generating zone, and the water inlet and outlet are respectively connected to the water inlet storage tank and the water outlet storage tank through pipelines.

[0011] Preferably, the electrochemical reactor is a hollow cylindrical structure consisting of an upper sealing cover, a lower sealing cover and an annular reactor shell; the outer ring anode is fitted to the reactor shell, and the inner ring anode is fitted to the central fixed axis.

[0012] Preferably, the outer ring anode, the annular mesh cathode and the inner ring anode are at the same height, and the upper and lower ends are respectively in the same horizontal plane.

[0013] Preferably, the outer ring anode and the inner ring anode are plate anodes, and the porosity of the mesh cathode is 20% to 40%; the material of the outer ring anode and the inner ring anode is one of titanium, titanium-based oxygen-plated compounds, nickel, and nickel-based oxygen-plated compounds, and the material of the mesh cathode is stainless steel.

[0014] Preferably, the water quality monitoring device includes a display screen, a numerical control device and an online monitoring probe, which are used to measure the chemical oxygen demand, ammonia nitrogen content, total nitrogen content, total phosphorus content, pH value, water level and conductivity value of the water body; the numerical control device is used to feed back the water body index results measured by the online monitoring probe to the power supply device; the display screen is used to display the water body index results measured by the online monitoring probe.

[0015] Preferably, the inner spiral generator comprises an inner propeller hub and inner propeller blades; the inner propeller hub is sleeved and fixed on the spiral center axis, and inner propeller blades are continuously provided on the outside along the circumferential direction, and the circumference where the outer end of the inner propeller blade is located is consistent in size with the circumference where the inner ring of the mesh cathode is located; the outer spiral generator comprises outer propeller blades and an outer propeller hub; the outer propeller hub is sleeved and fixed on the spiral center axis, and outer propeller blades are continuously provided on the outside along the circumferential direction, and the circumference where the outer end of the outer propeller blade is located is consistent in size with the circumference where the outer ring anode is located, and the circumference where the inner end is located is consistent in size with the circumference where the outer ring of the mesh cathode is located.

[0016] Furthermore, the number of the inner and outer propeller blades is 3 to 6, and the axial inclination angle of the plane where the blade body is located relative to the central screw axis is 35° to 40°, the rotation speed is 600 to 2000 rpm / min, the blade thickness is 1.5 to 3 mm and the outer edge is arc-shaped.

[0017] Preferably, the power supply device comprises a power supply and a relay; the power supply is in a constant current power supply mode, and the current density is 2-100 mA / cm 2 , the cable is 150~300mm 2 Single-core soft wire; the relay is used for timing control of the on / off time of the power supply.

[0018] Preferably, the water inlet and outlet are externally connected to a first pipeline and a second pipeline in parallel; the first pipeline is provided with an inlet pump and an inlet electric valve, which are connected to the inlet liquid storage tank; the second pipeline is provided with an outlet pump and an outlet electric valve, which are connected to the outlet liquid storage tank.

[0019] In a second aspect, the present invention provides a method for treating organic wastewater using any of the internal circulation rotating impinging flow electrocatalytic devices described in the first aspect, as follows:

[0020] The high-concentration organic wastewater to be treated in the water inlet storage tank enters the vortex generating area from the water inlet port through the water inlet pump, and the wastewater enters the electrochemical reaction area from bottom to top until the defined water level line; the online monitoring probe is immersed in water and transmits the water level information to the display screen, and the water inlet pump and the water inlet electric valve switch are regulated by the numerical control device, and the driving electrode in the vortex generating area is turned on at the same time to make the inner spiral generator and the outer spiral generator rotate in opposite directions at a speed of 600 to 2000 rpm / min respectively, and the power supply of the power supply device connected to the outer ring anode, the mesh cathode and the inner ring anode is turned on;

[0021] By adjusting the inclination angle and inclination direction of the blades in the inner spiral generator and the outer spiral generator, the wastewater is made to swirl in opposite directions in the inner reaction zone and the outer reaction zone, and the wastewater swirls upward in the inner reaction zone, pushes to the top of the electrochemical reactor, and then swirls downward along the outer reaction zone, so as to perform spiral internal circulation electrolysis in the inner reaction zone and the outer reaction zone; in this process, on the one hand, the formation of a reaction dead zone in the electrochemical reactor can be avoided, the concentration difference can be eliminated to a greater extent, and the treatment efficiency can be improved; on the other hand, the introduction of the swirl field can promote the disturbance around the electrode and the renewal process of the electrode surface components, and avoid the occurrence of bubble attachment on the electrode surface; at the same time, the outward swirl in the inner reaction zone and the inward swirl in the outer reaction zone collide at the mesh cathode in the middle, forming an impact flow under high-speed flow, generating a strong turbulent zone, greatly promoting mass transfer, and at the same time, due to the collapse of the cavitation bubble formed by the impact flow, hydroxyl free radicals, oxygen free radicals, singlet oxygen, superoxide free radicals, hydrogen peroxide and other active substances are generated, effectively removing difficult-to-degrade organic matter;

[0022] The waste gas generated in the electrochemical reaction zone during the electrolysis process is discharged from the electrochemical reactor through the automatic exhaust valve and enters the waste gas storage tank for pressurized collection; the water quality indicators of the sewage are monitored in real time by the water quality monitoring device. When the wastewater treatment is completed and reaches the specified indicators, the CNC device opens the water outlet pump and the water outlet electric valve and cuts off the power supply, and the waste gas is discharged to the water outlet storage tank through the water inlet and outlet and finally discharged.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1) The internal circulation rotating impinging flow reactor of the present invention is of tubular design, and the anode and cathode are arranged alternately, and has the characteristics of large specific surface area, and the internal cathode is a mesh structure, so that the active sites of the electrocatalytic reaction are significantly increased and the electrode stability is better.

[0025] 2) Under the action of the swirl generator, the inner reaction zone forms a swirl from bottom to top and outward, and the swirl to the top of the reactor forms a swirl from top to bottom and inward under the action of the external spiral generator, forming an internal circulation fluid, which greatly enhances the electrochemical mass transfer performance, promotes internal fluid turbulence, and avoids the formation of reaction dead zones. Compared with conventional reactors, the swirl design can greatly enhance the shear stress of the fluid on the surface of the electrode plate, which is beneficial to prevent calcium and magnesium scaling and the formation of bubble curtains on the surface of the plate, improve current efficiency, and increase the service life of the electrode.

[0026] 3) A cavitation impact flow is formed inside the reactor. The outward swirling force inside the reactor and the inward swirling force outside the reactor are continuously impacted and hydraulically cavitated on the surface of the mesh cathode, synchronously realizing the electrocatalytic and electrochemical processes, which is suitable for the deep treatment of various sewage.

[0027] 4) The device is equipped with a water quality monitoring system and an automatic setting system to monitor the water quality online and automatically set the treatment time according to the treatment effect.

[0028] 5) The device is safe to operate, with an internal waste gas collection system. The automatic exhaust valve absorbs the chlorine and hydrogen generated during the reaction by means of negative pressure vacuum suction. The absorbed waste gas is uniformly collected and processed in the waste gas storage system to avoid explosions during the electrocatalytic process.

[0029] 6) The overall design is easy to process, install, maintain and overhaul, and the operation is simple and flexible. The processing components in the reactor are compact, which greatly reduces the footprint of the equipment. Due to the compact design of the equipment, the construction and maintenance process is simpler and reduces the relevant costs. The present invention can be a plug-and-play on-site assembly mode without the need for a special design of the reaction device. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the device of the present invention;

[0031] Figure 2 is a side view of the electrochemical reactor;

[0032] Figure 3 is a top view of the electrochemical reaction zone in the electrochemical reactor;

[0033] Figure 4 It is a top view of the swirl generating area in the electrochemical reactor;

[0034] In the above figures, 1-electrochemical reaction zone, 2-vortex generating zone, 3-power supply device, 4-power supply, 5-relay, 6-water quality monitoring device, 7-display screen, 8-numerical control device, 9-online monitoring probe, 10-reactor shell, 11-automatic exhaust valve, 12-gas storage tank, 13-upper sealing cover, 14-outer reaction zone, 15-outer ring anode, 16-mesh cathode, 17-inner reaction zone, 18-inner ring anode, 19-water inlet and outlet, 20-inner slurry hub, 21-inner propeller blade, 22-outer propeller blade, 23-outer slurry hub, 24-spiral gear, 25-spiral central shaft, 26-water inlet storage tank, 27-water inlet pump, 28-water outlet storage tank, 29-water outlet pump, 30-lower sealing cover, 31-central fixed shaft, 32-water inlet electric valve, 33-water outlet electric valve. DETAILED DESCRIPTION

[0035] The present invention is further described and illustrated below in conjunction with the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly without conflicting with each other.

[0036] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside" and "outside" etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.

[0037] like Figure 1 As shown, an internal circulation rotating impact flow electrocatalytic device for treating organic wastewater provided by the present invention mainly includes an electrochemical reactor, an inlet liquid storage tank 26, an outlet liquid storage tank 28, a water quality monitoring device 6, a power supply device 3 and a gas storage tank 12.

[0038] The structure and connection method of each component will be described in detail below.

[0039] In the device of the present invention, Figure 2 As shown, the electrochemical reactor is a columnar structure with a closed inner cavity, the upper part of the inner cavity is an electrochemical reaction zone 1, the lower part of the inner cavity is a vortex generating zone 2, and the electrochemical reaction zone 1 and the vortex generating zone 2 are interconnected. Figure 3 As shown, the anode plates and cathode plates are alternately arranged in a concentric circle structure inside the electrochemical reaction zone 1, that is, the outer ring anode 15, the annular mesh cathode 16, the inner ring anode 18 and the central fixed shaft 31 are coaxially sleeved in sequence from the outside to the inside of the electrochemical reaction zone 1. Among them, there is a certain interval between the outer ring anode 15 and the mesh cathode 16, and there is a certain interval between the mesh cathode 16 and the inner ring anode 18. The annular area between the outer ring anode 15 and the mesh cathode 16 constitutes the outer reaction zone 14, and the annular area between the mesh cathode 16 and the inner ring anode 18 constitutes the inner reaction zone 17. The outer reaction zone 14 and the inner reaction zone 17 are connected above and below. The outer ring anode 15, the annular mesh cathode 16 and the inner ring anode 18 are all connected to the power supply device 3 located outside the electrochemical reactor in a separately controlled form. The power supply device supplies power to each electrical device at the same time.

[0040] As a preferred embodiment of the present invention, the outside of the electrochemical reactor is a hollow cylindrical structure consisting of an upper sealing cover 13, a lower sealing cover 30 and an annular reactor shell 10, that is, the top of the reactor shell 10 is sealed and connected to the upper sealing cover 13, and the bottom of the reactor shell 10 is sealed and connected to the lower sealing cover 30. The outer ring anode 15 is fitted and connected to the annular inner wall of the reactor shell 10, and the inner ring anode 18 is fitted and connected to the outer wall of the central fixed shaft 31.

[0041] As a preferred embodiment of the present invention, the outer ring anode 15, the annular mesh cathode 16 and the inner ring anode 18 have the same height, are all cylindrical in structure, and have their upper and lower ends at the same level.

[0042] As a preferred embodiment of the present invention, the outer ring anode 15 and the inner ring anode 18 are single-layer plate anodes; the mesh cathode 16 is a double-layer mesh electrode with a porosity of 20% to 40%. The outer ring anode 15 and the inner ring anode 18 are made of titanium, titanium-based oxygen-plated compounds, nickel, and nickel-based oxygen-plated compounds. The two anode plates can use the same material or different materials according to actual conditions. In the reaction chamber with titanium-based lead dioxide-plated or titanium-based ruthenium-iridium-plated materials as anodes, the anode can electrocatalyze the generation of hydroxyl free radicals with strong oxidizing properties, and the cathode can generate oxidizing hydrogen peroxide, thereby oxidizing organic matter and nitrogen adsorbed on the surface of the particle filler and in the sewage, playing the role of degrading pollutants and regenerating particle fillers; when the sewage contains chloride ions, active chlorine can also be formed in the reactor to oxidize pollutants, thereby improving the efficiency of removing pollutants.

[0043] As a preferred embodiment of the present invention, the mesh cathode 16 is made of stainless steel. The outer ring anode 15 and the inner ring anode 18 are connected to the positive electrode of the power supply device 3 outside the electrochemical reactor in a separately controlled manner, and the mesh cathode 16 is connected to the negative electrode of the power supply device 3 outside the electrochemical reactor in a separately controlled manner.

[0044] As a preferred embodiment of the present invention, all device shells are insulated and non-conductive to ensure safe use. The non-conductive material can be polytetrafluoroethylene, organic glass, polycarbonate, etc., so as to avoid the danger of conductive leakage of the device shell and extend the use time. In order to avoid rusting of the device, the shell where the vortex generating area is located and the spiral generator are made of stainless steel. The thickness of stainless steel and organic glass should be reasonably selected according to the actual operating water volume. In actual use, the electrochemical reaction area and the vortex generating area can be detachably connected as two devices.

[0045] In the device of the present invention, Figure 4As shown, the swirl generating area 2 is a coaxial reverse spiral structure, and two groups are arranged on the central fixed shaft, which are respectively connected with two groups of propeller blades arranged vertically to realize coaxial reverse spiral. Specifically as follows: the swirl generating area 2 includes an inner spiral generator and an outer spiral generator sleeved on the spiral central shaft 25, and the spiral central shaft 25 is coaxially connected below the central fixed shaft 31. The inner spiral generator is located below the inner reaction zone 17, and the outer spiral generator is located below the outer reaction zone 14. The inner spiral generator and the outer spiral generator are respectively connected to the central spiral shaft 25 through a spiral gear 24. The spiral central shaft 25 is driven to rotate by a driving device, which can drive the two spiral gears 24 to rotate in the opposite direction, so that the blades of the inner spiral generator and the outer spiral generator stir the water flow of the inner reaction zone 17 and the outer reaction zone 14 in a coaxial reverse spiral manner to present a reverse swirl. In actual use, the two spiral gears 24 are respectively connected to the inner slurry hub 20 of the inner spiral generator and the outer slurry hub 23 of the outer spiral generator.

[0046] As a preferred embodiment of the present invention, the inner spiral generator includes an inner propeller hub 20 and inner propeller blades 21. The inner propeller hub 20 is sleeved and fixed on the spiral central axis 25, and the inner propeller blades 21 are continuously arranged on the outer side along the circumferential direction. The circumference where the outer end of the inner propeller blade 21 is located is consistent in size with the circumference where the inner ring of the mesh cathode 16 is located, so that the inner propeller blade 21 mainly generates a disturbed vortex to the water body of the inner reaction zone 17 when rotating.

[0047] In actual use, the number of inner propeller blades 21 is 3 to 6, and they are evenly distributed on the outer periphery of the inner propeller hub 20. The plane where the blade body of the inner propeller blade 21 is located is inclined at an angle of 35° to 40° relative to the axial direction of the central propeller shaft 25. The speed is controlled to be 600 to 2000 rpm / min under the action of the driving device. The blade body thickness of the inner propeller blade 21 is 1.5 to 3 mm, and the outer edge of the body is arc-shaped to reduce fluid resistance. The number of blades, the inclination angle of the blade body, the thickness and the speed can be adjusted according to actual conditions.

[0048] As a preferred embodiment of the present invention, the outer spiral generator includes an outer spiral blade 22 and an outer slurry hub 23. The outer slurry hub 23 is sleeved and fixed on the spiral central axis 25, and the outer spiral blade 22 is continuously arranged on the outer circumference. The circumference of the outer end of the outer spiral blade 22 is consistent with the circumference of the outer ring anode 15, and the circumference of the inner end is consistent with the circumference of the outer ring of the mesh cathode 16, so that the outer spiral blade 22 mainly generates a disturbed vortex to the water body of the outer reaction zone 14 when rotating.

[0049] In actual use, the number of the outer propeller blades 22 is 3 to 6, and they are evenly distributed on the outer periphery of the outer propeller hub 23. The plane where the blade body of the outer propeller blade 22 is located is inclined at an angle of 35° to 40° relative to the axial direction of the central propeller shaft 25. The speed is controlled to be 600 to 2000 rpm / min under the action of the driving device. The blade body thickness of the outer propeller blade 22 is 1.5 to 3 mm, and the outer edge of the body is arc-shaped to reduce fluid resistance. The number of blades, the inclination angle of the blade body, the thickness and the speed can be adjusted according to actual conditions.

[0050] Specifically, by adjusting the axial inclination angle and inclination direction of the inner and outer propeller blades 21 and 22 relative to the central propeller shaft 25, the inner propeller blades 21 can be rotated under the action of the driving device to form a vortex that spirals upward and outward, and the outer propeller blades 22 can be formed to form a vortex that spirals downward and inward, thereby forming an internal circulation impact flow inside the electrochemical reactor.

[0051] In the device of the present invention, Figure 1 As shown, an automatic exhaust valve 11 connected to the electrochemical reaction zone 1 is provided on the top of the electrochemical reactor. The automatic exhaust valve 11 is connected to an external gas storage tank 12 through a pipeline, and then pressurized separation is performed to treat the waste gas as a resource.

[0052] In actual application, after the electrochemical reaction device 1 is powered on, hydrogen, chlorine and oxygen are generated inside the reactor due to the electrochemical reaction. An automatic exhaust valve 11 is arranged on the upper part of the reactor to absorb the waste gas generated during the reaction by means of negative pressure vacuum suction. The absorbed gas is uniformly collected and processed in the tail gas storage tank 12 to avoid air pollution and explosion. The automatic exhaust valve 11 is rotated to the top of the reactor and the switch is turned on when in use, and is rotated to the side of the reactor and the switch is turned off when not in use.

[0053] In the device of the present invention, Figure 1 As shown, the online monitoring probe 9 of the water quality monitoring device 6 extends below the liquid surface of the electrochemical reaction zone 1. The side wall of the electrochemical reactor located in the cyclone generating zone 2 is provided with a water inlet and outlet 19, and the inlet and outlet water share a water inlet and outlet port, and the water inlet and outlet 19 are connected to the water inlet storage tank 26 and the water outlet storage tank 28 through pipelines.

[0054] As a preferred embodiment of the present invention, the water quality monitoring device 6 mainly includes a display screen 7, a numerical control device 8 and an online monitoring probe 9, which are used to measure the chemical oxygen demand (COD) and ammonia nitrogen (NH4 + -N) content, total nitrogen (TN) content, total phosphorus (TP) content, pH value, water level and conductivity value. The numerical control device 8 is used to feed back the water index results measured by the online monitoring probe 9 to the power supply device 3. The display screen 7 is used to display the water index results measured by the online monitoring probe 9.

[0055] As a preferred embodiment of the present invention, the power supply device 3 includes a power supply 4 and a relay 5. The power supply 4 is in a constant current power supply mode, and the current density is 2-100 mA / cm 2 . Depending on the applied current, the cable is 150 to 300 mm 2 Single core soft wire can prevent the cable from overloading and heating due to high current. Relay 5 is used to control the switching time of the power supply, thereby controlling the time and process of the reaction.

[0056] As a preferred embodiment of the present invention, the water inlet and outlet 19 is externally connected to a first pipeline and a second pipeline in parallel. The first pipeline is provided with a water inlet pump 27 and a water inlet electric valve 32, which is connected to the water inlet liquid storage tank 26. The second pipeline is provided with a water outlet pump 29 and a water outlet electric valve 33, which is connected to the water outlet liquid storage tank 28.

[0057] The present invention also provides a method for treating organic wastewater by using the internal circulation rotating impact flow electrocatalytic device. The method is specifically as follows:

[0058] The high-concentration organic wastewater to be treated in the water inlet storage tank 26 enters the vortex generating area 2 from the water inlet port 19 through the water inlet pump 27, and the wastewater enters the electrochemical reaction area 1 from bottom to top until the defined water level line. The online monitoring probe 9 is immersed in water and transmits the water level information to the display screen 7, and the water inlet pump 27 and the water inlet electric valve 32 are regulated by the numerical control device 8. At the same time, the driving electrode in the vortex generating area 2 is turned on to make the inner spiral generator and the outer spiral generator rotate in the opposite direction at a speed of 600 to 2000 rpm / min, and the power supply 4 of the power supply device 3 connected to the outer ring anode 15, the mesh cathode 16 and the inner ring anode 18 is turned on.

[0059] By adjusting the inclination angle and inclination direction of the blades in the inner spiral generator and the outer spiral generator, the wastewater is swirled in opposite directions in the inner reaction zone 17 and the outer reaction zone 14, and the wastewater swirls upward in the inner reaction zone 17, pushes to the top of the electrochemical reactor, and then swirls downward along the outer reaction zone 14, thereby performing spiral internal circulation electrolysis in the inner reaction zone 17 and the outer reaction zone 14. In this process, on the one hand, the formation of a reaction dead zone in the electrochemical reactor can be avoided, the concentration difference can be eliminated to a greater extent, and the treatment efficiency can be improved. On the other hand, the introduction of the swirling field can promote the disturbance around the electrode and the renewal process of the electrode surface components, and avoid the occurrence of bubble attachment on the electrode surface. At the same time, the outward swirling flow of the inner reaction zone 17 and the inward swirling flow of the outer reaction zone 14 collide at the middle mesh cathode 16, forming an impact flow under high-speed flow, producing a strong turbulent zone, which greatly promotes mass transfer. At the same time, due to the collapse of cavitation bubbles formed by the impact flow, active substances such as hydroxyl free radicals, oxygen free radicals, singlet oxygen, superoxide free radicals, hydrogen peroxide, etc. are generated, which effectively remove difficult-to-degrade organic matter.

[0060] The waste gas generated in the electrochemical reaction zone 1 during the electrolysis process is discharged from the electrochemical reactor through the automatic exhaust valve 11 and enters the waste gas storage tank 12 for pressurized collection. The water quality index of the sewage is monitored in real time by the water quality monitoring device 6. When the wastewater treatment is completed and reaches the specified index, the numerical control device 8 opens the water outlet pump 29 and the water outlet electric valve 33 and cuts off the power supply 4, and the wastewater is discharged to the water outlet storage tank 28 through the water inlet and outlet 19 and finally discharged.

[0061] During the electrolytic treatment of wastewater, bubbles will be generated on the surface of the anode and cathode plates due to the hydrogen and oxygen evolution reactions and attached to the plates, resulting in a reduction in the number of active sites on the plate surface, which in turn increases the ohmic drop, which increases the electrolysis energy consumption and reduces the degradation efficiency. Through high-speed swirl, the bubbles attached to the plate surface can be quickly separated from the plate surface by shear force, which is conducive to maintaining the maximum plate activity at all times, increasing the electrochemical reaction area, and improving the component transfer and mass transfer performance in the reactor, ultimately achieving the purpose of strengthening the electrochemical oxidation process and improving the degradation effect.

[0062] The present invention combines the impinging flow technology with the electrocatalytic technology for high-concentration industrial wastewater, and utilizes the vortex generating area to realize the internal circulation impinging flow. It has the advantages of high treatment efficiency, small footprint, and low operating energy consumption. It can solve the problem of bubble adhesion on the electrode surface, and form strong turbulence through impact, reduce the reaction dead zone, and enhance the mass transfer in the electrochemical degradation device, so as to achieve the purpose of automated operation and efficient degradation. It is of great significance in the treatment scenario of high-concentration organic wastewater.

[0063] The above embodiment is only a preferred solution of the present invention, but it is not intended to limit the present invention. A person skilled in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent replacement or equivalent transformation falls within the protection scope of the present invention.

Claims

1. An internal circulation rotating impinging current electrocatalytic device for treating organic wastewater, characterized in that: It comprises an electrochemical reactor, a water inlet storage tank (26), a water outlet storage tank (28), a water quality monitoring device (6), a power supply device (3) and a gas storage tank (12); The electrochemical reactor is a columnar structure with a closed inner cavity, the upper part of the inner cavity is an electrochemical reaction zone (1), and the lower part is a vortex generating zone (2); the electrochemical reaction zone (1) comprises an outer ring anode (15), an annular mesh cathode (16), an inner ring anode (18) and a central fixed shaft (31) which are coaxially sleeved in sequence from the outside to the inside; the annular region between the outer ring anode (15) and the mesh cathode (16) constitutes an outer reaction zone (14); the annular region between the mesh cathode (16) and the inner ring anode (18) constitutes an inner reaction zone (17); the outer reaction zone (14) and the inner reaction zone (17) are connected at the top and the bottom; the outer ring anode (15), the annular mesh cathode (16) and the inner ring anode (18) are all connected to the power supply device (3) in a separately controlled manner; The swirl generating area (2) comprises an inner spiral generator and an outer spiral generator which are sleeved on a spiral central shaft (25), and the spiral central shaft (25) is coaxially connected to the lower part of the central fixed shaft (31); the inner spiral generator is located below the inner reaction area (17), and the outer spiral generator is located below the outer reaction area (14), and the inner spiral generator and the outer spiral generator are respectively connected to the central spiral shaft (25) through spiral gears (24); the spiral central shaft (25) is driven to rotate by a driving device, which can drive the two spiral gears (24) to rotate in the opposite direction, so that the blades of the inner spiral generator and the outer spiral generator stir the water flow in the inner reaction area (17) and the outer reaction area (14) in a coaxial reverse spiral manner to present a reverse swirl; An automatic exhaust valve (11) in communication with the electrochemical reaction zone (1) is provided on the top of the electrochemical reactor, and the automatic exhaust valve (11) is connected to an external gas storage tank (12) through a pipeline; an online monitoring probe (9) of the water quality monitoring device (6) extends below the liquid surface of the electrochemical reaction zone (1); a water inlet and outlet (19) are provided on the side wall of the electrochemical reactor located in the vortex generating zone (2), and the water inlet and outlet (19) are respectively connected to a water inlet storage tank (26) and a water outlet storage tank (28) through pipelines.

2. The internal circulation rotating impinging flow electrocatalytic device for treating organic wastewater according to claim 1, characterized in that: The electrochemical reactor is a hollow cylindrical structure consisting of an upper sealing cover (13), a lower sealing cover (30) and an annular reactor shell (10); an outer ring anode (15) is arranged in close contact with the reactor shell (10), and an inner ring anode (18) is arranged in close contact with a central fixed shaft (31).

3. The internal circulation rotating impinging flow electrocatalytic device for treating organic wastewater according to claim 1, characterized in that: The outer ring anode (15), the annular mesh cathode (16) and the inner ring anode (18) are at the same height, and the upper and lower ends are respectively located at the same horizontal plane.

4. The internal circulation rotating impinging flow electrocatalytic device for treating organic wastewater according to claim 1, characterized in that: The outer ring anode (15) and the inner ring anode (18) are plate anodes, and the porosity of the mesh cathode (16) is 20% to 40%. The outer ring anode (15) and the inner ring anode (18) are made of one of titanium, titanium-based oxygen-plated compounds, nickel, and nickel-based oxygen-plated compounds, and the mesh cathode (16) is made of stainless steel.

5. The internal circulation rotating impinging flow electrocatalytic device for treating organic wastewater according to claim 1, characterized in that: The water quality monitoring device (6) comprises a display screen (7), a numerical control device (8) and an online monitoring probe (9), and is used to measure the chemical oxygen demand, ammonia nitrogen content, total nitrogen content, total phosphorus content, pH value, water level and conductivity value of the water body; the numerical control device (8) is used to feed back the water body index results measured by the online monitoring probe (9) to the power supply device (3); and the display screen (7) is used to display the water body index results measured by the online monitoring probe (9).

6. The internal circulation rotating impinging flow electrocatalytic device for treating organic wastewater according to claim 1, characterized in that: The inner spiral generator comprises an inner propeller hub (20) and inner propeller blades (21); the inner propeller hub (20) is sleeved and fixed on the spiral central axis (25), and the inner propeller blades (21) are continuously arranged on the outside along the circumferential direction, and the circumference where the outer end of the inner propeller blade (21) is located is consistent in size with the circumference where the inner ring of the mesh cathode (16) is located; the outer spiral generator comprises an outer propeller blade (22) and an outer propeller hub (23); the outer propeller hub (23) is sleeved and fixed on the spiral central axis (25), and the outer propeller blades (22) are continuously arranged on the outside along the circumferential direction, and the circumference where the outer end of the outer propeller blade (22) is located is consistent in size with the circumference where the outer ring anode (15) is located, and the circumference where the inner end is located is consistent in size with the circumference where the outer ring of the mesh cathode (16) is located.

7. The internal circulation rotating impinging flow electrocatalytic device for treating organic wastewater according to claim 6, characterized in that: The number of the inner propeller blades (21) and the outer propeller blades (22) is 3 to 6, the axial inclination angle of the plane where the blade body is located relative to the central propeller axis (25) is 35° to 40°, the rotation speed is 600 to 2000 rpm / min, the blade thickness is 1.5 to 3 mm, and the outer edge is arc-shaped.

8. The internal circulation rotating impinging flow electrocatalytic device for treating organic wastewater according to claim 1, characterized in that: The power supply device (3) comprises a power supply (4) and a relay (5); the power supply (4) is in a constant current power supply mode, and the current density is 2 to 100 mA / cm 2 , the cable is 150~300mm 2 Single-core soft wire; the relay (5) is used to control the switching time of the power supply.

9. The internal circulation rotating impinging flow electrocatalytic device for treating organic wastewater according to claim 1, characterized in that: The water inlet and outlet (19) are externally connected to a first pipeline and a second pipeline in parallel; the first pipeline is provided with a water inlet pump (27) and a water inlet electric valve (32) and is in communication with a water inlet liquid storage tank (26); the second pipeline is provided with a water outlet pump (29) and a water outlet electric valve (33) and is in communication with a water outlet liquid storage tank (28).

10. A method for treating organic wastewater using the internal circulation rotating impinging current electrocatalytic device according to any one of claims 1 to 9, characterized in that: The details are as follows: The high-concentration organic wastewater to be treated in the water inlet storage tank (26) enters the vortex generating area (2) through the water inlet port (19) via the water inlet pump (27), and the wastewater enters the electrochemical reaction area (1) from bottom to top until the defined water level line; the online monitoring probe (9) is immersed in water and transmits the water level information to the display screen (7), and the water inlet pump (27) and the water inlet electric valve (32) are regulated by the numerical control device (8), and the driving electrode in the vortex generating area (2) is turned on at the same time to make the inner spiral generator and the outer spiral generator rotate in opposite directions at a speed of 600 to 2000 rpm / min, and the power supply (4) of the power supply device (3) connected to the outer ring anode (15), the mesh cathode (16) and the inner ring anode (18) is turned on; By adjusting the inclination angle and inclination direction of the blades in the inner spiral generator and the outer spiral generator, the wastewater is caused to swirl in opposite directions in the inner reaction zone (17) and the outer reaction zone (14), and the wastewater swirls upward in the inner reaction zone (17), flows to the top of the electrochemical reactor, and then swirls downward along the outer reaction zone (14), thereby performing spiral internal circulation electrolysis in the inner reaction zone (17) and the outer reaction zone (14); in this process, on the one hand, the formation of a reaction dead zone in the electrochemical reactor can be avoided, the concentration difference can be eliminated to a greater extent, and the treatment efficiency can be improved; on the other hand, In terms of the above aspects, the introduction of the cyclonic flow field can promote the disturbance around the electrode and the renewal process of the electrode surface components, thereby avoiding the occurrence of bubble attachment on the electrode surface; at the same time, the outward cyclonic flow of the inner reaction zone (17) and the inward cyclonic flow of the outer reaction zone (14) collide at the mesh cathode (16) in the middle, forming an impact flow under high-speed flow, generating a strong turbulent zone, greatly promoting mass transfer, and at the same time, due to the collapse of the cavitation bubbles formed by the impact flow, hydroxyl free radicals, oxygen free radicals, singlet oxygen, superoxide free radicals, and hydrogen peroxide active substances are generated, effectively removing difficult-to-degrade organic matter; The waste gas generated in the electrochemical reaction zone (1) during the electrolysis process is discharged from the electrochemical reactor through the automatic exhaust valve (11) and enters the waste gas storage tank (12) for pressurized collection; the water quality index of the sewage is monitored in real time through the water quality monitoring device (6); when the wastewater treatment is completed and reaches the specified index, the numerical control device (8) opens the water outlet pump (29) and the water outlet electric valve (33) and cuts off the power supply (4), and the waste gas is discharged to the water outlet storage tank (28) through the water inlet and outlet (19) and finally discharged.

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