Wastewater degradation system and method based on cooperation of radial microchannel discharge and cavitation

Abstract

The invention discloses a wastewater degradation system and a wastewater degradation method based on cooperation of radial microchannel discharge and cavitation, and belongs to the technical field of organic wastewater treatment. The device comprises a waste liquid pool, a micro-channel discharge cavitation degradation device, an ozone generator, a Venturi tube and a collection pool, the Venturi tube is respectively communicated with the ozone generator, the waste liquid pool and a to-be-degraded wastewater inlet of the micro-channel discharge cavitation degradation device. A dielectric barrier discharge technology and a hydrodynamic cavitation technology are fused, a large number of active substances are generated in the inner and outer cavitation cavities through dielectric barrier discharge, a strong cavitation effect is generated around the rotor in cooperation with rotation of the cavitation rotor, and organic wastewater is degraded; by arranging the radial micro-channel discharge device, the discharge area is increased, the number of active substances such as ozone and hydroxyl radicals in gas and liquid phases is increased, and the inactivation loss of the active substances in the transportation process is reduced; and by arranging rotor cavitation teeth with opposite rotation directions, circular flow of a gas phase and a liquid phase is triggered, and the mass transfer efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of organic wastewater treatment, and in particular relates to a wastewater degradation system and method using radial microchannel discharge coordinated cavitation. Background Art

[0002] The discharge of wastewater containing organic pollutants is increasing day by day, and hydrodynamic cavitation technology and dielectric barrier discharge technology have received widespread attention in the field of organic wastewater treatment. Hydrodynamic cavitation technology triggers the rapid generation and collapse of bubbles in water through high pressure drop, which can instantly generate a high temperature and high pressure environment, stimulate the decomposition of water molecules, and produce highly oxidizing hydroxyl radicals (·OH) and other high-energy active particles, which can quickly degrade organic pollutants. However, the number of active particles produced by hydrodynamic cavitation itself is limited, and it is difficult to fully degrade high-concentration organic wastewater. On the other hand, dielectric barrier discharge technology breaks down the air by applying high voltage to form a plasma environment rich in high-energy electrons, free radicals and excited molecules. Plasma can excite and ionize water molecules to generate a large number of highly oxidizing active particles, such as ozone (O3), hydrogen peroxide (H2O2) and hydroxyl radicals (·OH), which overcomes the problem of less highly active particles produced by hydrodynamic cavitation technology. However, the active ions generated by dielectric barrier discharge have a short survival time in the liquid phase, resulting in limited degradation effect.

[0003] Therefore, the hydrodynamic cavitation technology is integrated with the dielectric barrier discharge technology to form a new type of wastewater degradation system. The large amount of active substances generated by the dielectric barrier discharge combined with the microbubbles generated by the hydrodynamic cavitation can not only improve the mass transfer efficiency between gas and liquid, but also promote the generation of strong oxidizing free radicals, thereby significantly improving the degradation efficiency of organic wastewater.

[0004] The invention patent "An organic wastewater degradation device with microchannel gas-liquid two-phase micro-discharge" with announcement number CN 118479598 A discloses an organic wastewater degradation device with discharge in a microchannel, which includes: a plunger pump, a microchannel chip, a plasma power supply, etc. By turning on the plunger pump, the gas-liquid two-phase flow flows from the microchannel chip into the discharge reaction chamber, and the flow focusing structure in the microfluidic chip generates microbubbles, which are combined with cavitation phenomenon and dielectric barrier discharge technology to degrade organic wastewater. However, the device generates cavitation through the expansion and contraction structure, and it is difficult to generate uniform and continuous microbubbles in the flow field. Compared with the rotating cavitation device, the cavitation efficiency is low and the degradation capacity of wastewater is limited.

[0005] The invention patent "A three-stage hydraulic cavitation treatment system for organic wastewater" with announcement number CN 109824173 A discloses a three-stage hydraulic cavitation treatment system for organic wastewater, which includes: a precipitant tank, a coagulation tank, a sedimentation tank, a rotary hydraulic cavitator, a cavitation jet generator and an ultrasonic cavitator. The rotary hydraulic cavitator generates cavitation through the shear force of the rotor, the cavitation jet generator generates a cavitation jet, and the ultrasonic cavitator uses the cavitation phenomenon generated by ultrasound. The cavitated wastewater is finally oxidized and degraded in the Fenton reagent tank. Although the invention uses a combination of multiple cavitation technologies to treat organic wastewater, the active substances such as hydroxyl radicals generated by cavitation have partially lost their activity during the transportation process, resulting in poor degradation effect and low energy utilization of the system.

[0006] The invention patent with the announcement number CN 118005130 A, "A device for purifying industrial wastewater by discharge at room temperature and pressure and its application method", discloses a device and method for purifying industrial wastewater by discharge at room temperature and pressure, the method comprising: placing an electrode tube in the center of an outer sleeve to form a discharge tube. An air compression tube is arranged in the airway; the discharge tube is placed in the wastewater to be purified, and the compressed air tube continuously adds high-pressure air to the airway, and discharges the gas-liquid mixture under the action of high frequency and high pressure, and the gas-liquid mixture is ionized into a plasma containing a large number of hydroxyl free radicals. Although this method changes the surface discharge in the prior art into a body discharge, which increases the magnitude of plasma discharge. However, the device can only ionize the air in the airway, and cannot form a larger discharge area within a limited volume, which limits the further improvement of the degradation efficiency.

[0007] The invention patent "A system and method for degrading organic wastewater by hydrodynamic cavitation and plasma" with the announcement number CN 119118415 A discloses a system and method for degrading organic wastewater by hydrodynamic cavitation and plasma, which includes a liquid storage tank, an aeration device and a plasma rotary cavitation reactor. A large number of cavitation bubbles are generated in the organic wastewater in the plasma rotary cavitation reactor and a dielectric barrier plasma discharge is formed in the plasma discharge chamber through the jet cavitation channel, generating ozone and hydroxyl radicals in the water. However, the device uses two traditional coaxial annular plates for surface discharge, and the cavitation and discharge process can only be carried out on the outer wall of the rotor, resulting in low efficiency of hydrodynamic cavitation and dielectric barrier plasma discharge.

[0008] In summary, the existing hydrodynamic cavitation synergistic discharge device for degrading organic wastewater still has the following problems in practical application:

[0009] First, the dielectric barrier discharge area is small, and the active substances (such as hydroxyl radicals, high-energy electrons and excited molecules) generated during the plasma discharge process have a short life in the liquid phase. When these active substances are transferred from the plasma area to the hydrodynamic cavitation area, they will be consumed in large quantities due to diffusion and reaction inactivation. The insufficient dielectric barrier discharge area directly leads to the inefficient use of active substances and poor degradation effect.

[0010] Second, hydrodynamic cavitation and low-temperature plasma discharge technology cannot achieve synergistic degradation. The high-energy active substances generated in the plasma discharge area cannot contact the microbubbles in the hydrodynamic cavitation area in time, making it difficult for the active substances to fully exert their strong oxidizing effect, limiting the further improvement of the degradation efficiency. Summary of the invention

[0011] In order to solve the above-mentioned problems in the prior art, the present application provides a wastewater degradation system and method with radial microchannel discharge coordinated cavitation, which provides a new technical solution for achieving efficient degradation of organic wastewater.

[0012] The technical solution is as follows:

[0013] On the one hand, a wastewater degradation system with radial microchannel discharge and cavitation coordination is provided, comprising a waste liquid pool 1, a microchannel discharge cavitation degradation device 8, an ozone generator 5, a venturi tube 6 and a collection pool 9, wherein the ozone generator 5 is connected to the venturi tube 6, the venturi tube 6 is respectively connected to the waste liquid pool 1 and the microchannel discharge cavitation degradation device 8, the microchannel discharge cavitation degradation device 8 is connected to the collection pool 9, and the ozone generator 5 is respectively connected to the venturi tube 6 and the air pump 3;

[0014] The microchannel discharge cavitation degradation device 8 includes a driving mechanism 81, a conductive slip ring 82 connected to the driving mechanism 81, a cavitation stator 83, a cavitation rotor 85 located in the cavitation stator 83, a degradation device base 84 and a radial microchannel discharge device 86 fixed between the cavitation stator 83 and the degradation device base 84.

[0015] According to a further technical solution, the wastewater degradation system is also provided with a peristaltic pump 7 and an overflow valve 4. The wastewater in the waste liquid pool 1 is transported through the peristaltic pump 7 to a gas-liquid two-phase flow containing ozone microbubbles through a venturi tube 6 and sent to a microchannel discharge cavitation degradation device 8. The overflow valve 4 is respectively connected to the microchannel discharge cavitation degradation device 8 and a collection pool 9, and both ends of the DC pump 2 are respectively connected to the waste liquid pool 1 and the venturi tube 6.

[0016] A further technical solution is that the drive mechanism 81 includes a rotor drive shaft 812, a motor support seat 813, a cavitation rotor motor 811 fixedly mounted on the motor support seat 813, a drive mechanism fixing seat 816 fixedly connected to the motor support seat 813, and a drive shaft upper bearing 814 and a drive shaft lower bearing 815 fixedly mounted on the drive mechanism fixing seat 816. The rotor drive shaft 812 is passed through concentric holes formed by the conductive slip ring 82, the drive shaft upper bearing 814, and the drive shaft lower bearing 815 to form a tight fit. The rotor drive shaft 812 is connected to the cavitation rotor 85, and the rotor drive shaft 812 drives the cavitation rotor 85 to rotate.

[0017] A further technical solution is that the radial microchannel discharge device 86 comprises a discharge device water inlet chamber 861, a plurality of micro jet holes 862 arranged on the inner wall of the discharge device water inlet chamber 861, an annular negative plate 863, a cylindrical discharge chamber 864, a threaded hole 865, a discharge rod 866, an annular positive plate 867 and an annular cavity 868, the micro jet holes 862 connect the discharge device water inlet chamber 861 and the cylindrical discharge chamber 864, and are radially distributed with the axis of the discharge device water inlet chamber 861 as the center; the cylindrical discharge chamber 864 is provided with a plurality of micro jet holes 862 on the inner wall of the discharge device water inlet chamber 861, ... One end is connected to the annular negative plate 863, and the other end is connected to the inner cavitation cavity 834; the discharge rod 866 is fixed in the threaded hole 865, the annular positive plate 867 is arranged in the sealed cavity of the discharge rod 866 and is tightly connected to the inner wall of the sealed cavity of the discharge rod 866, the annular negative plate 863 is arranged in the annular cavity 868 and is tightly connected to the inner wall of the annular cavity 868, the annular cavity 868 is close to the outer wall of the cylindrical discharge chamber 864, and a small discharge gap is formed between the outer wall of the discharge rod 866 and the inner wall of the cylindrical discharge chamber 864. In the prior art solution, the dielectric barrier discharge mode is generally a surface discharge between coaxial or parallel two plates, and the radial structure transforms the traditional surface discharge into a body discharge. The radial structure also allows the dielectric barrier discharge area to extend all the way around the inner wall of the cavitation rotor 85, reducing the deactivation loss of active substances during transportation.

[0018] A further technical solution is that a plurality of equidistant outer wall cavitation teeth 851 are provided on the outer wall surface of the cavitation rotor 85 along the direction of the cylindrical outer wall generatrix, the rotation direction is clockwise, and a plurality of equidistant axial grooves are formed between two adjacent outer wall cavitation teeth 851, and the groove surfaces of all axial grooves are parallel to the outer wall generatrix; a plurality of equidistant inner wall cavitation teeth 852 are provided on the inner wall surface of the cavitation rotor 85 along the direction of the conical inner wall generatrix, the rotation direction is counterclockwise, and a plurality of equidistant grooves are formed between two adjacent inner wall cavitation teeth 852, and the groove surfaces of all grooves are parallel to the inner wall generatrix;

[0019] A slit is formed between the outer wall cavitation teeth 851 and the inner wall of the outer cavitation cavity 833, and an expanded chamber is formed between the inter-tooth groove and the inner wall of the outer cavitation cavity 833. The slit and the chamber are constantly alternating with the rotation of the cavitation rotor 85, generating periodic pressure fluctuations, thereby inducing a cavitation effect; a periodic alternation between wide and narrow channels is also formed between the inner wall cavitation teeth 852 and the outer wall of the radial microchannel discharge device 86, inducing a cavitation effect between the inner wall cavitation teeth 852 and the outer wall of the radial microchannel discharge device 86. In the prior art solution, the cavitation rotor is generally a solid cylindrical gear-shaped structure, and the cavitation rotor 85 with the inner cavitation cavity 834 has both discharge and cavitation functions around the outer wall cavitation teeth 851 and the inner wall cavitation teeth 852.

[0020] As a further technical solution, a plurality of equally spaced rotor cavitation channels 854 are radially opened between the outer wall and the inner wall of the cavitation rotor 85 , which are radially distributed with the axis of the cavitation rotor 85 as the center; the rotor cavitation channels 854 connect the outer cavitation cavity 833 with the inner cavitation cavity 834 .

[0021] A further technical solution is that the cavitation stator 83 includes a degradation wastewater outlet 831 and a stator annular negative electrode 832. The degradation wastewater outlet 831 is opened at the top of the outer cavitation cavity 833, passes through the upper end surface of the cavitation stator 83, and is connected to the overflow valve 4 through a pipeline; the stator annular negative electrode 832 is arranged in the annular sealed cavity in the cavitation stator 83, and is tightly connected to the inner wall of the annular sealed cavity, and a small discharge gap is formed between the inner wall of the cavitation stator 83 and the outer wall of the cavitation rotor 85.

[0022] As a further technical solution, the relative dielectric constant of the material used for the cavitating stator 83 and the cavitating rotor 85 should be greater than 3.8.

[0023] A further technical solution is to introduce gas-liquid two-phase flow into the outer cavitation cavity 833 and the inner cavitation cavity 834, and the cavitation rotor 85 rotates stably at a certain speed. The torque output by the cavitation rotor motor 811 during operation is calculated based on the size parameters and operation parameters of the rotor.

[0024] Assume that the viscosity of industrial wastewater is μ, in units of Pa·s, the rotational angular velocity of the cavitation rotor 85 is ω, in units of r / min, and the vertical distance from the rotor center axis to the rotor outer wall is r o , unit m, the vertical distance from the rotor center axis to the stator inner wall is R, unit m, the clearance of the cylinder wall is δ = Rr o , unit is m, the vertical distance from the upper surface to the lower surface of the rotor is L o , unit is m. According to Newton's law of internal friction, the friction force T on the outer wall of the rotor caused by the viscosity of the external cavitation cavity 833 industrial wastewater o , unit N, the friction force is calculated according to formula (1):

[0025]

[0026] Among them, τ is the shear stress on the outer wall of the rotor, A is the outer surface area of ​​the rotor, and in order to balance the friction force T on the outer wall of the rotor o , the required torsional torque of the rotor is M o , unit N·m, the value of the torsional moment is calculated according to formula (2):

[0027]

[0028] Assume that the vertical distance from the rotor center axis to the rotor inner wall is r i , unit m, the vertical distance from the central axis of the rotor to the outer wall of the radial microchannel discharge device (86) is r, unit m, and the gap of the conical wall inside the rotor is δ′=r i -r, unit m, the vertical distance from the upper surface of the rotor cavity to the bottom of the rotor is L i , unit is m. According to formula (2), in order to balance the friction force on the inner wall of the rotor, the required torsional moment of the rotor is M i , unit N·m, the value of the torsional moment is calculated according to formula (3):

[0029]

[0030] If the space between the outer wall and the inner wall of the rotor is filled with industrial wastewater, according to equations (2) and (3), the torque required for the rotor to rotate at an angular velocity ω is M r , unit N·m, the value of the total torsional moment is calculated according to formula (4):

[0031]

[0032] After measuring the viscosity μ of the industrial wastewater and the rotational angular velocity ω of the cavitation rotor 85 , the torque value required for the rotor to work can be calculated according to Formula 4. By adjusting the torque of the cavitation rotor motor 811 , the cavitation rotor 85 can be operated with the minimum torsional torque, thereby reducing the energy consumption of the cavitation rotor motor 811 .

[0033] On the other hand, a wastewater degradation method using radial microchannel discharge and cavitation is provided, using the above-mentioned wastewater degradation system, the method comprising:

[0034] Step 1: The water storage tank 1 stores industrial organic wastewater, the DC pump 2 and the air pump 3 are turned on, and the industrial organic wastewater is pumped into the venturi tube 6. The ozone generated by the ozone generator 5 is simultaneously injected into the venturi tube 6 to fully mix the ozone with the industrial organic wastewater;

[0035] Step 2: The pressure inside the industrial organic wastewater is released at the throat of the venturi tube 6, producing a cavitation effect and generating a large number of microbubbles with ozone. The industrial organic wastewater with microbubbles is pumped into the microchannel discharge cavitation degradation device 8 through the peristaltic pump 7;

[0036] Step 3: The peristaltic pump 7 pumps the industrial organic wastewater with microbubbles into the wastewater injection port 841. When the wastewater fills the cavity in the entire degradation device base 84, the wastewater enters the discharge device water inlet cavity 861 under the action of water pressure, and performs dielectric barrier discharge in the cylindrical discharge chamber 864 through the microjet holes 862 to generate ozone and hydroxyl radicals.

[0037] Step 4: After the industrial organic wastewater enters the inner cavitation cavity 834, the cavitation rotor motor 811 is started, and the cavitation rotor 85 rotates to induce a strong cavitation effect around the inner wall cavitation teeth 852. The organic wastewater is sucked from the inner cavitation cavity 834 to the outer cavitation cavity 833 through the rotor cavitation channel 854, and a dielectric barrier discharge is formed between the outer wall of the cavitation rotor 85 and the inner wall of the cavitation stator 83. The cavitation effect generated by the outer wall cavitation teeth 851 is combined to deeply degrade the industrial organic wastewater.

[0038] Step 5: After the degradation wastewater outlet (831) reaches a certain water pressure, the overflow valve (4) opens the passage between the degradation wastewater outlet (831) and the collection tank (9), and the purified industrial organic wastewater flows into the collection tank (9) for storage.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] (1) The present invention designs a radial microchannel discharge device. By setting radially distributed micro jet holes on the inner wall of the water inlet chamber, wastewater with a large number of micro bubbles is introduced into the cylindrical discharge chamber, so that the cylindrical discharge chamber realizes body discharge, effectively increasing the discharge area and the amount of active substances generated. The radial structure also allows the dielectric barrier discharge area to extend all the way to the inner wall of the cavitation rotor, reducing the deactivation loss of active substances during transportation and improving the efficiency of wastewater treatment.

[0041] (2) The present invention designs a multiple discharge cavitation process based on dielectric barrier discharge technology and hydrodynamic cavitation technology. The wastewater undergoes the first dielectric barrier discharge in the cylindrical discharge chamber, generating low-temperature plasma rich in active substances in the organic wastewater, and the local high temperature, high pressure and mechanical shock waves generated when the cavitation bubbles in the inner cavity of the cavitation rotor collapse, so that the ozone molecules with a long life and poor water solubility can fully react with the organic wastewater. When the wastewater is squeezed into the outer cavitation cavity, the second dielectric barrier discharge is carried out, and the cavitation effect of the outer wall of the cavitation rotor is combined to strengthen the degradation process.

[0042] (3) The present invention optimizes the cavitation rotor structure. By setting up an inner cavitation cavity, when the rotor rotates, the inner and outer cavitation cavities simultaneously generate strong shear forces, thereby enhancing the cavitation effect and accelerating the generation and collapse of bubbles. The inner wall of the rotor is conical, which increases the contact area between the inner wall cavitation teeth and the wastewater, enhances the cavitation effect of the wastewater, and improves the gas-liquid mass transfer efficiency.

[0043] (4) The present invention designs a cyclic degradation process of wastewater. The rotor is provided with inner wall cavitation teeth and outer wall cavitation teeth with opposite rotation directions. The inner wall cavitation teeth form an attraction force on the gas-liquid phase around the inner wall of the rotor, attracting the gas-liquid phase to quickly pass through the jet holes to reach the outer cavitation teeth. The outer wall cavitation teeth form a centrifugal force on the gas-liquid phase around the outer wall of the rotor, and the gas-liquid phase is squeezed to the vicinity of the inner wall cavitation teeth, forming a cyclic flow in the microchannel discharge cavitation degradation device, making the degradation process more thorough.

[0044] (5) The present invention designs a method for calculating the minimum torsional torque when the rotor is running. Based on the torque balance analysis, the distribution of friction forces on the inner and outer walls of the rotor and the torque formula are calculated. According to the relationship between the viscosity of industrial wastewater and the rotation speed, the rotation speed is adjusted to make the rotor motor output the lowest friction torque, thereby achieving the goal of minimizing the rotor energy consumption while meeting the process requirements of wastewater degradation and improving the economic efficiency of the degradation reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0046] Figure 1 A schematic diagram of a wastewater degradation system using radial microchannel discharge and cavitation synergism provided by an embodiment of the present invention;

[0047] Figure 2 A schematic diagram of the structure of a microchannel discharge cavitation degradation device provided by an embodiment of the present invention;

[0048] Figure 3 A schematic structural diagram of a conical radial microchannel discharge device provided by an embodiment of the present invention;

[0049] Figure 4 for Figure 3 Schematic diagram of the structure of the discharge rod;

[0050] Figure 5 A schematic diagram of the structure of a cavitation rotor provided in an embodiment of the present invention;

[0051] Figure 6 A schematic diagram of the structure of a rotor annular positive electrode provided in an embodiment of the present invention;

[0052] Figure 7A schematic diagram of the structure of a cavitation stator provided in an embodiment of the present invention;

[0053] Figure 8 A schematic diagram of the structure of a microchannel discharge cavitation degradation device provided in an embodiment of the present invention;

[0054] Fig. 9 A schematic diagram of the structure of a degradation device base provided by an embodiment of the present invention;

[0055] Fig.10 A flow diagram in a microchannel discharge cavitation degradation device provided by an embodiment of the present invention;

[0056] Fig.11 A flow chart of a wastewater degradation process provided by an embodiment of the present invention.

[0057] Explanation of the reference numerals: 1. waste liquid tank; 2. DC pump; 3. air pump; 4. overflow valve; 5. ozone generator; 6. venturi tube; 7. peristaltic pump; 8. microchannel discharge cavitation degradation device; 81. driving mechanism; 811. cavitation rotor motor; 812. rotor driving shaft; 813. motor support seat; 814. upper bearing of driving shaft; 815. lower bearing of driving shaft; 816. driving mechanism fixing seat; 82. conductive slip ring; 83. cavitation stator; 831. degradation wastewater outlet; 832. stator annular negative electrode; 833. External cavitation cavity; 834, internal cavitation cavity; 84, degradation device base; 841, wastewater injection port; 85, cavitation rotor; 851, outer wall cavitation teeth; 852, inner wall cavitation teeth; 853, rotor annular positive pole; 854, rotor cavitation channel; 86, radial microchannel discharge device; 861, discharge device water inlet cavity; 862, micro jet hole; 863, annular negative plate; 864, cylindrical discharge chamber; 865, threaded hole; 866, discharge rod; 867, annular positive plate; 868, annular cavity; 9, collection tank. DETAILED DESCRIPTION

[0058] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0059] The present invention integrates dielectric barrier discharge technology and hydraulic cavitation technology, and designs a wastewater degradation system with radial microchannel discharge and coordinated cavitation. Industrial organic wastewater generates a gas-liquid two-phase flow containing ozone microbubbles through a venturi tube 6 and an ozone generator 5, and a peristaltic pump 7 pumps the gas-liquid two-phase flow into the inlet of the wastewater to be degraded of a microchannel discharge cavitation degradation device 8; the bubbles are further electrically broken down in the inner and outer cavitation cavities by dielectric barrier discharge to generate more ozone, and a strong cavitation effect is generated around the cavitation rotor in coordination with the rotation of the cavitation rotor 85, so that the ozone bubbles are fully dissolved in the liquid to generate hydroxyl radicals, and the organic wastewater is degraded through strong mixed mass transfer; a radial microchannel discharge device 86 is provided to increase the discharge area, increase the amount of active substances such as ozone and hydroxyl radicals in the gas-liquid phase, and improve the degradation efficiency; and by providing rotor cavitation teeth of opposite rotation directions, a circulating flow of the gas-liquid phase is induced, thereby improving the mass transfer efficiency.

[0060] like Figure 1 As shown, the present invention provides a wastewater degradation system with radial microchannel discharge coordinated cavitation. In some embodiments, it includes a waste liquid pool 1, a microchannel discharge cavitation degradation device 8, an ozone generator 5, a venturi tube 6 and a collection pool 9, the ozone generator 5 is connected to the venturi tube 6, the venturi tube 6 is respectively connected to the waste liquid pool 1 and the microchannel discharge cavitation degradation device 8, and the microchannel discharge cavitation degradation device 8 is connected to the collection pool 9; the ozone generator 5 is respectively connected to the venturi tube 6 and the air pump 3, the air pump 3 inhales air to generate ozone in the oxygen generator 5, and the generated ozone is passed into the venturi tube 6; the wastewater in the waste liquid pool 1 generates a gas-liquid two-phase flow containing ozone microbubbles through the venturi tube 6, and the gas-liquid two-phase flow is pumped to the microchannel discharge cavitation degradation device 8 by a peristaltic pump 7; the microchannel discharge cavitation degradation device 8 is used to degrade the wastewater, and the waste liquid pool 1 is used to store industrial organic wastewater to be degraded.

[0061] Furthermore, the overflow valve 4 is connected to the degradation wastewater outlet 831 of the microchannel discharge cavitation degradation device 8 and the collection tank 9 through pipelines.

[0062] like Figure 2As shown, in one embodiment, the microchannel discharge cavitation degradation device 8 includes a driving mechanism 81, a conductive slip ring 82, a cavitation stator 83, a degradation device base 84, a cavitation rotor 85 and a radial microchannel discharge device 86; the driving mechanism 81 includes a cavitation rotor motor 811, the cavitation rotor motor 811 is fixed to the motor support seat 813 by bolts, and the motor support seat 813 is connected to the driving mechanism fixing seat 816 by bolts; the driving shaft upper bearing 814 and the driving shaft lower bearing 815 are installed on the driving mechanism fixing seat 816, and the rotor driving shaft 812 is penetrated in the concentric holes formed by the conductive slip ring 82, the driving shaft upper bearing 814, and the driving shaft lower bearing 815 to form a tight fit. The cavitation rotor 85 is located in the cavitation stator 83, and is connected to the rotor driving shaft 812 by threads, and the rotor driving shaft 812 drives the cavitation rotor 85 to rotate.

[0063] like Figure 2-Figure 4 As shown, in one embodiment, the radial microchannel discharge device 86 is fixed between the cavitation stator 83 and the degradation device base 84 by bolts. The radial microchannel discharge device 86 includes a discharge device water inlet chamber 861, micro jet holes 862, annular negative plate 863, a cylindrical discharge chamber 864, a threaded hole 865, a discharge rod 866, annular positive plate 867 and annular cavity 868. A plurality of micro jet holes 862 are arranged on the inner wall of the discharge device water inlet chamber 861, and the micro jet holes 862 connect the discharge device water inlet chamber 861 and the cylindrical discharge chamber 864, and are radially distributed with the axis of the discharge device water inlet chamber 861 as the center; one end of the cylindrical discharge chamber 864 is connected to the annular negative plate 863, and the other end is connected to the inner cavitation chamber 834.

[0064] Figure 4 As shown, in one embodiment, the discharge rod 866 is fixed in the threaded hole 865 by screwing, and a sealed cavity is provided inside the discharge rod 866. The annular positive plate 867 is placed in the sealed cavity and is tightly connected to the inner wall of the cavity of the discharge rod 866; the annular negative plate 863 is placed in the annular cavity 868 and is tightly connected to the inner wall of the annular cavity 868, and the annular cavity 868 is close to the outer wall of the cylindrical discharge chamber 864. A small discharge gap is formed between the outer wall of the discharge rod 866 and the inner wall of the cylindrical discharge chamber 864. When the industrial organic wastewater enters the cylindrical discharge chamber 864 from the water inlet cavity 861 of the discharge device through the micro jet hole 862, a dielectric barrier discharge phenomenon is formed in several cylindrical discharge chambers 864, forming a body discharge, which greatly increases the discharge area. In the prior art, the dielectric barrier discharge method is generally a surface discharge between two coaxial or parallel electrodes. The radial structure in the embodiment of the present application transforms the traditional surface discharge into a body discharge, and also allows the dielectric barrier discharge area to extend all the way to the inner wall of the cavitation rotor 85, thereby reducing the deactivation loss of active substances during transportation.

[0065] Figure 5 and Figure 6 As shown, in one embodiment, the cavitation rotor 85 includes outer wall cavitation teeth 851, inner wall cavitation teeth 852, rotor annular positive pole 853, and rotor cavitation channel 854. A plurality of equidistant outer wall cavitation teeth 851 are provided on the outer wall surface of the cavitation rotor 85 along the direction of the cylindrical outer wall generatrix, the rotation direction is clockwise, and a plurality of equidistant axial grooves are formed between two adjacent outer wall cavitation teeth 851, and the groove surfaces of all axial grooves are parallel to the outer wall generatrix; a plurality of equidistant inner wall cavitation teeth 852 are provided on the inner wall surface of the cavitation rotor 85 along the direction of the conical inner wall generatrix, the rotation direction is counterclockwise, and a plurality of equidistant grooves are formed between two adjacent inner wall cavitation teeth 852, and the groove surfaces of all grooves are parallel to the inner wall generatrix.

[0066] Furthermore, a plurality of equally spaced rotor cavitation channels 854 are radially opened between the outer wall surface and the inner wall surface of the cavitation rotor 85 , which are radially distributed with the axis of the cavitation rotor 85 as the center; the cavitation channels 854 connect the outer cavitation cavity 833 with the inner cavitation cavity 834 .

[0067] Figure 2 and Figure 5 As shown, when the cavitation rotor 85 rotates, a slit is formed between the outer wall cavitation teeth 851 and the inner wall of the outer cavitation cavity 833, and the gas-liquid phase flow rate suddenly increases in the slit, causing the pressure to drop rapidly, and an expanded chamber is formed between the groove between the teeth and the inner wall of the outer cavitation cavity 833, which increases the gas-liquid phase pressure. The slit and the chamber are constantly alternating with the rotation of the cavitation rotor 85, generating periodic pressure fluctuations, thereby inducing the cavitation effect; the inner wall cavitation teeth 852 and the outer wall of the radial microchannel discharge device 86 also form a periodic alternation between wide and narrow flow channels, triggering the cavitation effect between the inner wall cavitation teeth 852 and the outer wall of the radial microchannel discharge device 86. A large number of cavitation bubbles generated inside and outside the rotor burst rapidly to release active substances and energy, which has a strong degradation effect on pollutants in wastewater.

[0068] Figure 6 As shown, the rotor annular positive electrode 853 is arranged in the annular cavity of the cavitation rotor 85, and is tightly connected to the inner wall of the annular cavity 868; the rotor annular positive electrode 853 is connected to the conductive slip ring 82. The rotor annular positive electrode 853 is provided with through holes with the same direction, number and diameter as the rotor cavitation channel 854, and the axis of the through hole coincides with the axis of the rotor cavitation channel 854; the surface of the rotor annular positive electrode 853 is waterproofed.

[0069] In the prior art, the cavitation rotor is generally a solid cylindrical gear-shaped structure. The cavitation rotor 85 with the inner cavitation cavity 834 in this embodiment has both discharge and cavitation functions around the outer wall cavitation teeth 851 and the inner wall cavitation teeth 852.

[0070] Figure 7 and Fig. 9As shown, the cavitation stator 83 and the degradation device base 84 are tightly connected by bolts, and the cavitation stator 83 includes a degradation wastewater outlet 831 and a stator annular cathode 832. The degradation wastewater outlet 831 is opened at the top of the outer cavitation cavity 833, passes through the upper end surface of the cavitation stator 83, and is connected to the overflow valve 4 through a pipeline; the stator annular cathode 832 is arranged in the annular sealed cavity in the cavitation stator 83, and is tightly connected to the inner wall of the annular sealed cavity. A small discharge gap is formed between the inner wall of the cavitation stator 83 and the outer wall of the cavitation rotor 85.

[0071] Furthermore, to ensure that the dielectric barrier discharge can break through the gas-liquid phase discharge, the relative dielectric constant of the material used for the cavitation stator 83, the cavitation rotor 85 and the discharge rod 866 should be greater than 3.8.

[0072] Figure 8 As shown, the gas-liquid two-phase flow is introduced into the outer cavitation cavity 833 and the inner cavitation cavity 834, and the cavitation rotor 85 rotates stably at a certain speed. The torque output by the rotor motor 811 during operation can be accurately calculated through the size parameters and operation parameters of the rotor, so as to avoid outputting excessive torque while meeting the load requirements and reduce energy consumption.

[0073] Assume that the viscosity of industrial wastewater is μ, in units of Pa·s, the rotational angular velocity of the cavitation rotor 85 is ω, in units of r / min, and the vertical distance from the rotor center axis to the rotor outer wall is r o , unit is m, the vertical distance from the rotor center axis to the inner wall of the stator is R, unit is m. The clearance of the cylinder wall is δ=Rr o , unit is m. The vertical distance from the upper surface to the lower surface of the rotor is L o , unit is m. According to Newton's law of internal friction, the friction force T on the outer wall of the rotor caused by the viscosity of the external cavitation cavity 833 industrial wastewater O , unit N, the friction force is calculated according to formula (1):

[0074]

[0075] Among them, τ is the shear stress on the outer wall of the rotor, and A is the outer surface area of ​​the rotor. At this time, in order to balance the friction force T on the outer wall of the rotor o , the required torsional torque of the rotor is M O , unit N·m, the value of the torsional moment is calculated according to formula (2):

[0076] Assume that the vertical distance from the rotor center axis to the rotor inner wall is r i , unit is m, the vertical distance from the rotor center axis to the outer wall of the radial microchannel discharge device 86 is r, unit is m. Therefore, the clearance of the rotor inner conical wall is δ′=r i-r, unit: m. The vertical distance from the upper surface of the rotor cavity to the bottom of the rotor is L i , unit is m. According to formula (2), in order to balance the friction force on the inner wall of the rotor, the required torsional torque of the rotor is M i , unit N·m, the value of the torsional moment is calculated according to formula (3):

[0077]

[0078] If the space between the outer wall and the inner wall of the rotor is filled with industrial wastewater, according to equations (2) and (3), the torque required for the rotor to rotate at an angular velocity ω is M r , unit N·m, the value of the total torsional moment is calculated according to formula (4):

[0079]

[0080] If the viscosity of wastewater is 3×10 -3 Pa·s, the angular velocity of the cavitation rotor is 2000r / min, the vertical distance from the upper surface to the lower surface of the rotor is 0.1m, and the vertical distance from the upper surface of the rotor cavity to the bottom surface of the rotor is 0.15m. The vertical distance from the central axis of the rotor to the outer wall of the rotor is 0.1m, and the vertical distance from the central axis of the rotor to the inner wall of the rotor is 0.05m. The gap of the cylinder wall is 0.1m, and the gap of the inner conical wall of the rotor is 0.1m. The minimum torque that needs to be applied at this time is calculated to be 0.12N·m.

[0081] In summary, the minimum torsional torque of the cavitation rotor is calculated. Through torque balance analysis, the distribution of friction on the inner and outer walls of the cavitation rotor and the torque formula are calculated, and according to the relationship between the viscosity of industrial wastewater and the speed, the speed is adjusted to make the rotor motor output the lowest friction torque, while minimizing the rotor energy consumption, meeting the process requirements of wastewater degradation, and improving the economy of the degradation reaction.

[0082] like Fig.10 and Fig.11 As shown, the present invention also provides a wastewater degradation method using radial microchannel discharge and cavitation, which uses the above-mentioned wastewater degradation system using radial microchannel discharge and cavitation, and includes the following steps:

[0083] Step 1: The water storage tank 1 stores industrial organic wastewater, the DC pump 2 and the air pump 3 are turned on, and the industrial organic wastewater is pumped into the venturi tube 6. The ozone generated by the ozone generator 5 is simultaneously injected into the venturi tube 6 to fully mix the ozone with the industrial organic wastewater.

[0084] Step 2: The pressure inside the industrial organic wastewater is released at the throat of the venturi tube 6, producing a cavitation effect and generating a large number of microbubbles containing ozone. The industrial organic wastewater containing microbubbles is pumped into the microchannel discharge cavitation degradation device 8 through the peristaltic pump 7.

[0085] Step 3: The peristaltic pump 7 pumps the industrial organic wastewater with microbubbles into the wastewater injection port 841. When the wastewater fills the cavity in the entire degradation device base 84, the wastewater enters the water inlet cavity 861 of the discharge device under the action of water pressure, and performs dielectric barrier discharge in the cylindrical discharge chamber 864 through the microjet holes 862 to generate ozone and hydroxyl free radicals.

[0086] Step 4: After the industrial organic wastewater enters the inner cavitation cavity 834, the cavitation rotor motor 811 is started, and the cavitation rotor 85 rotates to induce a strong cavitation effect around the inner wall cavitation teeth 852. The organic wastewater is sucked from the inner cavitation cavity 834 into the outer cavitation cavity 833 through the rotor cavitation channel 854, and a dielectric barrier discharge is formed between the outer wall of the cavitation rotor 85 and the inner wall of the cavitation stator 83. The cavitation effect generated by the outer wall cavitation teeth 851 is combined to deeply degrade the industrial organic wastewater.

[0087] Step 5: After the degradation wastewater outlet 831 reaches a certain water pressure, the overflow valve 4 opens the passage between the degradation wastewater outlet 831 and the collection tank 9, and the purified industrial organic wastewater flows into the collection tank 9 for storage.

[0088] The terms "first", "second" and the like appearing in the present invention are only for the convenience of description to distinguish different components with the same name, and do not indicate a priority or primary and secondary relationship.

[0089] In addition, when an element is referred to as being "on" another element, the element may be directly on the other element, or may be indirectly on the other element with one or more intermediate elements interposed therebetween. In addition, when an element is referred to as being "connected to" another element, the element may be directly connected to the other element, or may be indirectly connected to the other element with one or more intermediate elements interposed therebetween. Hereinafter, the same reference numerals represent the same elements.

[0090] In the present invention, descriptions of directions or positional relationships indicated by “upper”, “lower”, “top”, “bottom”, “front”, “back”, “inside” and “outside” are used only to facilitate the description of the present invention, and do not indicate or imply that the device referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, it should not be understood as limiting the scope of protection of the present invention.

[0091] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent replacements for some of the technical features therein. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wastewater degradation system using radial microchannel discharge and cavitation, characterized in that: include: A waste liquid pool (1), a microchannel discharge cavitation degradation device (8), an ozone generator (5), a venturi tube (6) and a collection pool (9), wherein the ozone generator (5) is connected to the venturi tube (6), the venturi tube (6) is respectively connected to the waste liquid pool (1) and the microchannel discharge cavitation degradation device (8), the microchannel discharge cavitation degradation device (8) is connected to the collection pool (9), and the ozone generator (5) is respectively connected to the venturi tube (6) and the air pump (3); The microchannel discharge cavitation degradation device (8) comprises a driving mechanism (81), a conductive slip ring (82) connected to the driving mechanism (81), a cavitation stator (83), a cavitation rotor (85) located in the cavitation stator (83), a degradation device base (84), and a radial microchannel discharge device (86) fixed between the cavitation stator (83) and the degradation device base (84).

2. The wastewater degradation system according to claim 1, characterized in that: It is also provided with a peristaltic pump (7) and an overflow valve (4). The peristaltic pump (7) is used to generate a gas-liquid two-phase flow containing ozone microbubbles from wastewater in the waste liquid pool (1) through a venturi tube (6), and the gas-liquid two-phase flow is sent to a microchannel discharge cavitation degradation device (8). The overflow valve (4) is respectively connected to the microchannel discharge cavitation degradation device (8) and a collection pool (9). The two ends of the DC pump (2) are respectively connected to the waste liquid pool (1) and the venturi tube (6).

3. The wastewater degradation system according to claim 1, characterized in that: The driving mechanism (81) comprises a rotor driving shaft (812), a motor support seat (813), a cavitation rotor motor (811) fixedly mounted on the motor support seat (813), a driving mechanism fixing seat (816) fixedly connected to the motor support seat (813), and a driving shaft upper bearing (814) and a driving shaft lower bearing (815) fixedly mounted on the driving mechanism fixing seat (816); the rotor driving shaft (812) is inserted into concentric holes formed by a conductive slip ring (82), the driving shaft upper bearing (814), and the driving shaft lower bearing (815) to form a tight fit; the rotor driving shaft (812) is connected to the cavitation rotor (85), and the rotor driving shaft (812) drives the cavitation rotor (85) to rotate.

4. The wastewater degradation system according to claim 1, characterized in that: The radial microchannel discharge device (86) comprises a discharge device water inlet chamber (861), a plurality of micro jet holes (862) arranged on the inner wall of the discharge device water inlet chamber (861), an annular negative electrode plate (863), a cylindrical discharge chamber (864), a threaded hole (865), a discharge rod (866) fixed in the threaded hole (865), an annular positive electrode plate (867) and an annular cavity (868), wherein the micro jet holes (862) are connected to the discharge device water inlet chamber (861) and the cylindrical discharge chamber (864), and are radially arranged with the axis of the discharge device water inlet chamber (861) as the center. The cylindrical discharge chamber (864) is distributed in a shape; one end of the cylindrical discharge chamber (864) is connected to the annular negative electrode plate (863), and the other end is connected to the inner cavitation cavity (834); the annular positive electrode plate (867) is arranged in the sealed cavity of the discharge rod (866) and is tightly connected to the inner wall of the sealed cavity of the discharge rod (866); the annular negative electrode plate (863) is arranged in the annular cavity (868) and is tightly connected to the inner wall of the annular cavity (868); the annular cavity (868) is closely attached to the outer wall of the cylindrical discharge chamber (864); and a small discharge gap is formed between the outer wall of the discharge rod (866) and the inner wall of the cylindrical discharge chamber (864).

5. The wastewater degradation system according to claim 1, characterized in that: A plurality of equidistant outer wall cavitation teeth (851) are provided on the outer wall surface of the cavitation rotor (85) along the direction of the cylindrical outer wall generatrix, the rotation direction is clockwise, a plurality of equidistant axial grooves are formed between two adjacent outer wall cavitation teeth (851), and the groove surfaces of all the axial grooves are parallel to the outer wall generatrix; a plurality of equidistant inner wall cavitation teeth (852) are provided on the inner wall surface of the cavitation rotor (85) along the direction of the conical inner wall generatrix, the rotation direction is counterclockwise, a plurality of equidistant grooves are formed between two adjacent inner wall cavitation teeth (852), and the groove surfaces of all the grooves are parallel to the inner wall generatrix; a slit is formed between the outer wall cavitation teeth (851) and the inner wall of the outer cavitation cavity (833), and an expanded chamber is formed between the inter-tooth grooves and the inner wall of the outer cavitation cavity (833), and the slit and the chamber are alternated continuously with the rotation of the cavitation rotor (85).

6. The wastewater degradation system according to claim 5, characterized in that: A plurality of equally spaced rotor cavitation channels (854) are radially opened between the outer wall surface and the inner wall surface of the cavitation rotor (85), and are radially distributed with the axis of the cavitation rotor (85) as the center. The rotor cavitation channels (854) connect the outer cavitation cavity (833) with the inner cavitation cavity (834).

7. The wastewater degradation system according to claim 1, characterized in that: The cavitation stator (83) comprises a degradation wastewater outlet (831) and a stator annular negative electrode (832); the degradation wastewater outlet (831) is provided at the top of the outer cavitation cavity (833), passes through the upper end surface of the cavitation stator (83), and is connected to the overflow valve (4) through a pipeline; the stator annular negative electrode (832) is arranged in an annular sealed cavity in the cavitation stator (83), and is tightly connected to the inner wall of the annular sealed cavity; a tiny discharge gap is formed between the inner wall of the cavitation stator (83) and the outer wall of the cavitation rotor (85).

8. The wastewater degradation system according to claim 7, characterized in that: The relative dielectric constant of the material used for the cavitation stator (83), the cavitation rotor (85) and the discharge rod (866) should be greater than 3.

8.

9. The wastewater degradation system according to claim 1, characterized in that: A gas-liquid two-phase flow is introduced into the outer cavitation cavity (833) and the inner cavitation cavity (834), and the cavitation rotor (85) rotates stably at a certain speed. The torque output by the cavitation rotor motor (811) during operation is calculated based on the size parameters and operation parameters of the rotor; Assume that the viscosity of industrial wastewater is μ, in units of Pa·s, the rotational angular velocity of the cavitation rotor (85) is ω, in units of r / min, and the vertical distance from the rotor center axis to the rotor outer wall is r o , unit m, the vertical distance from the rotor center axis to the stator inner wall is R, unit m, the clearance of the cylinder wall is δ = Rr o , unit is m, the vertical distance from the upper surface to the lower surface of the rotor is L o , unit is m. According to Newton's law of internal friction, the friction force on the outer wall of the rotor caused by the viscosity of the industrial wastewater in the external cavitation cavity (833) is T o , unit N, the friction force is calculated according to formula (1): Among them, τ is the shear stress on the outer wall of the rotor, A is the outer surface area of ​​the rotor, and in order to balance the friction force T on the outer wall of the rotor o , the required torsional torque of the rotor is M o , unit N·m, the value of the torsional moment is calculated according to formula (2): Assume that the vertical distance from the rotor center axis to the rotor inner wall is r i , unit is m, the vertical distance from the central axis of the rotor to the outer wall of the radial microchannel discharge device (86) is r, unit is m, and the gap of the conical wall inside the rotor is δ ′ =r i -r, unit m, the vertical distance from the upper surface of the rotor cavity to the bottom of the rotor is L i , unit is m. According to formula (2), in order to balance the friction force on the inner wall of the rotor, the required torsional torque of the rotor is M i , unit N·m, the value of the torsional moment is calculated according to formula (3): If the space between the outer wall and the inner wall of the rotor is filled with industrial wastewater, the torque required for the rotor to rotate at an angular velocity ω is obtained according to equations (2) and (3): r , unit N·m, the value of the total torsional moment is calculated according to formula (4): After the viscosity μ of the industrial wastewater and the rotational angular velocity ω of the cavitation rotor (85) are measured, the torque value required for the rotor to work can be calculated according to formula (4). By adjusting the torque of the cavitation rotor motor (811), the cavitation rotor (85) can be operated with the minimum torsional torque, thereby reducing the energy consumption of the cavitation rotor motor (811).

10. A wastewater degradation method using radial microchannel discharge and cavitation, using the wastewater degradation system according to any one of claims 1 to 9, characterized in that: The method comprises: Step 1: The water storage tank (1) stores industrial organic wastewater, the DC pump (2) and the air pump (3) are turned on, and the industrial organic wastewater is pumped into the venturi tube (6). The ozone generated by the ozone generator (5) is simultaneously injected into the venturi tube (6) to fully mix the ozone and the industrial organic wastewater; Step 2: The pressure inside the industrial organic wastewater is released at the throat of the venturi tube (6), producing a cavitation effect and generating a large number of microbubbles containing ozone. The industrial organic wastewater containing microbubbles is pumped into the microchannel discharge cavitation degradation device (8) via a peristaltic pump (7); Step 3: The peristaltic pump (7) pumps the industrial organic wastewater with microbubbles into the wastewater injection port (841). When the wastewater fills the entire cavity in the degradation device base (84), the wastewater enters the discharge device water inlet cavity (861) under the action of water pressure, and performs dielectric barrier discharge in the cylindrical discharge chamber (864) through the microjet hole (862), thereby generating ozone and hydroxyl radicals. Step 4: After the industrial organic wastewater enters the inner cavitation cavity (834), the cavitation rotor motor (811) is started, and the cavitation rotor (85) rotates to induce a strong cavitation effect around the inner wall cavitation teeth (852). The organic wastewater is sucked from the inner cavitation cavity (834) into the outer cavitation cavity (833) through the rotor cavitation channel (854), and a dielectric barrier discharge is formed between the outer wall of the cavitation rotor (85) and the inner wall of the cavitation stator (83). The cavitation effect generated by the outer wall cavitation teeth (851) is combined to deeply degrade the industrial organic wastewater. Step 5: After the degradation wastewater outlet (831) reaches a certain water pressure, the overflow valve (4) opens the passage between the degradation wastewater outlet (831) and the collection tank (9), and the purified industrial organic wastewater flows into the collection tank (9) for storage.

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