Sewage treatment system

Abstract

The invention relates to a sewage treatment system which comprises a pretreatment device, a three-dimensional electrode catalytic oxidation device, a strong oxidation device and a separation device, the three-dimensional electrode catalytic oxidation device is communicated with the pretreatment device, and the three-dimensional electrode catalytic oxidation device comprises a shell, an anode electrode plate, a cathode electrode plate, a particle electrode assembly and a light source assembly; the anode electrode plate and the cathode electrode plate are arranged in the shell, the particle electrode assembly is arranged between the anode electrode plate and the cathode electrode plate, a containing space is formed among the anode electrode plate, the cathode electrode plate and the particle electrode assembly, the light source assembly is arranged in the containing space, and the surface of the cathode electrode plate and the surface of the particle electrode assembly are both coated with photocatalytic coatings. A photocatalyst is arranged in the photocatalytic coating; the strong oxidation device is communicated with the three-dimensional electrode catalytic oxidation device; the separation device is communicated with the strong oxidation device. The method is high in adaptability and can be applied to treatment of various types of pollutants.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and in particular to a sewage treatment system. Background Art

[0002] In the petrochemical storage industry, if there is a leak or natural disaster, a large amount of storage chemicals leaks, resulting in a large amount of high-concentration chemicals mixed and the wastewater produced contains a large amount of hydrocarbons, phenols, heavy metal ions and other difficult-to-degrade substances, which pose a serious threat to the environment and human health. Traditional sewage treatment technologies such as biological treatment and chemical precipitation are often difficult to effectively remove these pollutants and may cause secondary pollution. Therefore, it is necessary to develop a sewage treatment system that can non-selectively decompose organic molecules and oxidize them into harmless or low-toxic substances. Summary of the invention

[0003] Based on this, it is necessary to provide a sewage treatment system to address the problem that once storage chemicals leak, the sewage generated contains a large amount of difficult-to-degrade substances such as hydrocarbons, phenols, heavy metal ions, etc., which pose a serious threat to the environment and human health.

[0004] A sewage treatment system, comprising:

[0005] A pretreatment device for pre-treating sewage;

[0006] A three-dimensional electrode catalytic oxidation device, used for photoelectric oxidation treatment of pretreated sewage; the three-dimensional electrode catalytic oxidation device is connected to the pretreatment device, and the three-dimensional electrode catalytic oxidation device includes a shell, an anode electrode plate, a cathode electrode plate, a particle electrode assembly and a light source assembly, the anode electrode plate and the cathode electrode plate are arranged in the shell, the particle electrode assembly is arranged between the anode electrode plate and the cathode electrode plate, an accommodation space is arranged between the anode electrode plate, the cathode electrode plate and the particle electrode assembly, the light source assembly is arranged in the accommodation space, and the surfaces of the cathode electrode plate and the particle electrode assembly are coated with a photocatalytic coating, and the photocatalytic coating has a photocatalyst;

[0007] A strong oxidation device, used for strong oxidation treatment of the sewage after photoelectric oxidation treatment; the strong oxidation device is connected to the three-dimensional electrode catalytic oxidation device; and

[0008] The separation device is used for separating the solid and liquid of the sewage after the strong oxidation treatment, and the separation device is connected with the strong oxidation device.

[0009] In one embodiment, the particle electrode assembly includes a particle electrode and a filling basket for containing the particle electrode, the filling basket is a frame basket made of a mesh plate, and the photocatalytic coating is coated on the surface of the filling basket.

[0010] In one embodiment, the particle electrode is columnar activated carbon, the diameter of the activated carbon is 2-3 mm, and the height is 5-6 mm; the mesh holes of the mesh plate are 2 mm*2 mm.

[0011] In one embodiment, the light source assembly includes a quartz tube and an ultraviolet lamp. The quartz tube is vertically arranged in the accommodating space, the upper end of the quartz tube passes upward out of the shell, the bottom of the quartz tube is tightly connected to the shell, and the ultraviolet lamp is vertically arranged in the quartz tube.

[0012] In one embodiment, the three-dimensional electrode catalytic oxidation device also includes a water inlet pipe and an aeration pipe, which are arranged at the bottom of the shell, the water inlet pipe is connected to the pretreatment device, and the water inlet pipe is provided with water inlet holes along its length direction, the aeration pipe is connected to an external air pump, and the aeration pipe is provided with aeration holes along its length direction.

[0013] In one embodiment, the strong oxidation device includes a shell, a photocatalytic plate, an ultraviolet light source assembly and a drug supply assembly. The shell is arranged in a cylindrical structure, the photocatalytic plate is fixed to the circumferential inner wall of the shell, the ultraviolet light source assembly is arranged in the middle of the shell, and a drug inlet is arranged at the upper end of the shell, and the drug inlet is connected to the drug supply assembly.

[0014] In one embodiment, the photocatalytic plate is made of metallic titanium, the surface of the photocatalytic plate is coated with a photocatalytic coating, and the photocatalytic coating contains a photocatalyst.

[0015] In one embodiment, the photocatalyst is modified titanium dioxide doped with trivalent iron ions or modified titanium dioxide doped with conductive graphene.

[0016] In one embodiment, the drug supply assembly includes a drug tank, a drug supply pump, a drug supply valve and a drug supply flow meter. The drug inlet is connected to the drug tank through the drug supply pump. The drug supply valve and the drug supply flow meter are arranged between the drug supply pump and the outer casing. The drug tank stores hydrogen peroxide.

[0017] In one embodiment, the sewage treatment system also includes a water tank, a water quality detector, an output pump, a switching valve and a controller. The water tank is connected to the separation device, the water quality detector is arranged in the water tank, the inlet of the switching valve is connected to the water tank, one outlet of the switching valve is connected to an external connecting pipe, the other outlet of the switching valve is connected to the three-dimensional electrode catalytic oxidation device, the water quality detector is communicatively connected to the controller, and the output pump and the switching valve are electrically connected to the controller.

[0018] The beneficial effects of the present invention are as follows: by adopting the three-dimensional electrode and enhanced oxidation combination technology, an efficient and environmentally friendly sewage treatment system is constructed, and under the action of photocatalysis, a large number of free radicals (such as OH) can be generated, and these free radicals can non-selectively attack and decompose organic molecules, so that they are oxidized and decomposed into harmless or low-toxic substances, and a large amount of high-concentration, multi-component wastewater can be treated in a short period of time; the sewage treatment system of the present invention has strong adaptability and can be applied to the treatment of various types of pollutants, and can be used as a deep treatment technology for difficult-to-degrade phenol wastewater, and can also be used as a pre-treatment measure for difficult-to-degrade wastewater to improve biodegradability, and combined with traditional biological treatment methods to reduce treatment costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the structure of a sewage treatment system in one embodiment of the present invention;

[0020] Figure 2 It is an assembly structure diagram of the pre-treatment device in the sewage treatment system of the present invention;

[0021] Figure 3 A schematic diagram of the internal structure of a three-dimensional electrode catalytic oxidation device in a sewage treatment system of the present invention;

[0022] Figure 4 A schematic diagram of the internal structure of a three-dimensional electrode catalytic oxidation device in a sewage treatment system of the present invention from a top view;

[0023] Figure 5 It is a schematic diagram of the internal structure of the strong oxidation device in the sewage treatment system of the present invention.

[0024] The meanings of the numbers in the accompanying drawings are:

[0025] 100-Sewage treatment system;

[0026] 10-pretreatment device, 11-regulating tank, 12-grid, 13-sedimentation tank, 14-dosing mechanism, 141-dosing pipe, 142-dosing pump, 143-drug storage tank, 144-dosing valve, 145-dosing flow meter, 15-first pH sensor;

[0027] 20-three-dimensional electrode catalytic oxidation device, 21-shell, 22-anode electrode plate, 23-cathode electrode plate, 24-particle electrode assembly, 241-filling grid basket, 242-particle electrode, 25-light source assembly, 251-quartz tube, 252-ultraviolet lamp, 26-water inlet pipe, 261-water inlet hole, 27-aeration pipe, 271-aeration hole, 28-accommodation space;

[0028] 30-strong oxidation device, 31-housing, 32-photocatalytic plate, 33-ultraviolet light source assembly, 331-quartz tube, 332-ultraviolet lamp, 34-drug supply assembly, 341-drug tank, 342-drug supply pump, 343-drug supply valve, 344-drug supply flow meter, 35-second pH sensor;

[0029] 40- separation device;

[0030] 50-transport pump;

[0031] 60-transmission pump;

[0032] 70- pumping pump;

[0033] 80- output pump;

[0034] 90-switching valve;

[0035] 110- water storage tank;

[0036] 120-Water quality detector. DETAILED DESCRIPTION

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0038] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0039] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0040] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0042] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0043] See also Figure 1 , is a sewage treatment system 100 according to an embodiment of the present invention, comprising a pretreatment device 10, a three-dimensional electrode catalytic oxidation device 20, a strong oxidation device 30 and a separation device 40, wherein the pretreatment device 10 is used to pretreat sewage; the three-dimensional electrode catalytic oxidation device 20 is connected to the pretreatment device 10, the strong oxidation device 30 is connected to the three-dimensional electrode catalytic oxidation device 20, and the separation device 40 is connected to the strong oxidation device 30.

[0044] See also Figure 2The pretreatment device 10 includes a regulating tank 11, a grid 12, a sedimentation tank 13 and a dosing mechanism 14. The regulating tank 11 is provided with a water inlet and a water outlet. The grid 12 is provided at the water outlet, and the water outlet is connected to the sedimentation tank 13. The regulating tank 11 is provided with a dosing port, and the dosing port is connected to the dosing mechanism 14. The dosing mechanism 14 includes a dosing pipe 141, a dosing pump 142, a drug storage tank 143, a dosing valve 144 and a dosing flow meter 145. The dosing pump 142 is connected to the dosing port through the dosing pipe 141, and the dosing pump 142 is connected to the dosing storage tank. The dosing valve 144 and the dosing flowmeter 145 are arranged between the dosing pump 142 and the regulating tank 11. In this embodiment, there are two dosing mechanisms 14, and the drug storage tank 143 in one of the dosing mechanisms 14 mainly stores sodium hydroxide solution, and the drug storage tank 143 in the other dosing mechanism 14 mainly stores hydrochloric acid solution.

[0045] During operation, sewage enters the regulating tank 11 from the water inlet, and the pH value of the sewage is adjusted by the dosing mechanism 14 to make the pH value of the sewage reach 7. Large particles of impurities are removed through the grid 12, and then enters the sedimentation tank 13 to remove suspended matter and some oil substances, thereby stabilizing the water quality of the sewage.

[0046] See also Figure 1 The sewage treatment system 100 further includes a delivery pump 50, which is disposed between the sedimentation tank 13 and the three-dimensional electrode catalytic oxidation device 20, and is mainly used to deliver the sewage in the sedimentation tank 13 to the three-dimensional electrode catalytic device.

[0047] See also Figure 3 and Figure 4 The three-dimensional electrode catalytic device includes a shell 21, an anode electrode plate 22, a cathode electrode plate 23, a particle electrode assembly 24, a light source assembly 25, a water inlet pipe 26 and an aeration pipe 27. The inner wall of the shell 21 is provided with an anode slot and a cathode slot. The anode electrode plate 22 is inserted into the anode slot, and the cathode electrode plate 23 is inserted into the cathode slot. The anode electrode plate 22 is made of a natural graphite pressed flat plate, and the cathode electrode plate 23 is made of a metal titanium plate. The outer wall of the cathode electrode plate 23 is coated with a photocatalytic coating, and the photocatalytic coating has a photocatalyst. The photocatalyst is modified titanium dioxide doped with trivalent iron ions or modified titanium dioxide doped with conductive graphene. In this embodiment, the number of the anode electrode plate 22 and the cathode electrode plate 23 are both two, and the anode electrode plate 22 and the cathode electrode plate 23 are arranged parallel to each other.

[0048] See also Figure 3 and Figure 4The particle electrode assembly 24 is arranged between the anode electrode plate 22 and the cathode electrode plate 23. The particle electrode assembly 24 includes a particle electrode 242 and a filling grid basket 241 for containing the particle electrode 242. The particle electrode 242 is a columnar activated carbon with a diameter of 2-3 mm and a height of 5-6 mm. The filling grid basket 241 is fixedly arranged on the inner wall of the shell 21. The side end of the filling grid basket 241 does not contact the anode electrode plate 22 and the cathode electrode plate 23. This can effectively avoid the particle electrode assembly 24 from contacting the anode electrode plate 22 and the cathode electrode plate 23 and causing a short circuit. An opening is arranged above the filling grid basket 241, and the particle electrode 242 is placed into the filling grid basket 241 from the opening. The filling grid basket 241 is a frame basket made of a grid plate, the grid holes of the grid plate are 2mm*2mm, the material of the grid plate is metal titanium, the outer wall of the grid plate is coated with a photocatalytic coating, the photocatalytic coating has a photocatalyst, and the photocatalyst is modified titanium dioxide doped with trivalent iron ions or modified titanium dioxide doped with conductive graphene.

[0049] See also Figure 3 and Figure 4 , an accommodation space 28 is provided between the anode electrode plate 22, the cathode electrode plate 23 and the particle electrode assembly 24, the light source assembly 25 is provided in the accommodation space 28, the light source assembly 25 comprises a quartz tube 251 and an ultraviolet lamp 252, the quartz tube 251 is vertically provided in the accommodation space 28, the upper end of the quartz tube 251 is upwardly extended out of the shell 21, the bottom of the quartz tube 251 is tightly connected with the shell 21, and the ultraviolet lamp 252 is vertically provided in the quartz tube 251, so that sewage can not enter the quartz tube 251, and the ultraviolet lamp 252 can not be short-circuited. The water inlet pipe 26 and the aeration pipe 27 are provided at the bottom of the shell 21, the water inlet pipe 26 is connected with the delivery pump 50, and the water inlet pipe 26 is provided with a water inlet hole 261 along its length direction. The aeration pipe 27 is connected to an external air pump, and the aeration pipe 27 is provided with aeration holes 271 along its length. A sewage pipe is provided on the bottom side wall of the housing 21 .

[0050] During operation, sewage enters the housing 21 from the water inlet pipe 26, the anode electrode plate 22 is electrically connected to the positive electrode in the power supply, and the cathode electrode plate 23 is electrically connected to the negative electrode in the power supply. During the electrolysis process, the cathode electrode plate 23 releases electrons to reduce the cations in the sewage due to the electrons; the anode electrode plate 22 obtains electrons to cause the anions in the sewage to lose electrons and oxidize, so that some harmful substances in the sewage can be removed and free radicals can be generated; and the ultraviolet light emitted by the ultraviolet lamp 252 irradiates the cathode electrode plate 23 and the filling grid basket 241, so that the photocatalyst on its surface generates a large number of free radicals, and oxidizes and decomposes some organic matter in the sewage. At the same time, the aeration pipe 27 provides sufficient dissolved oxygen to effectively promote the efficiency of the photocatalytic reaction.

[0051] See also Figure 1 The sewage treatment system 100 also includes a delivery pump 60, which is arranged between the three-dimensional electrode catalytic device and the strong oxidation device 30. The delivery pump 60 is connected to the sewage pipe through a conduit, and is mainly used to deliver the sewage after the photoelectric oxidation reaction to the strong oxidation device 30.

[0052] See also Figure 5 The strong oxidation device 30 includes a shell 31, a photocatalytic plate 32, an ultraviolet light source assembly 33 and a drug supply assembly 34. The shell 31 is arranged in a cylindrical structure. An inlet is arranged at the upper end of the shell 31, and the inlet is connected to the transmission pump 60 through a conduit. The photocatalytic plate 32 is fixedly arranged on the inner wall of the shell 31, and the photocatalytic plate 32 is arranged in the circumference of the shell 31. The material of the photocatalytic plate 32 is metallic titanium. The surface of the photocatalytic plate 32 is coated with a photocatalytic coating, and the photocatalytic coating has a photocatalyst. The photocatalyst is modified titanium dioxide doped with trivalent iron ions or modified titanium dioxide doped with conductive graphene. The ultraviolet light source assembly 33 includes a quartz tube 331 and an ultraviolet lamp 332. The quartz tube 331 is vertically arranged in the middle of the housing 31. The upper end of the quartz tube 331 passes upwardly out of the housing 31. The bottom of the quartz tube 331 is tightly connected to the housing 31. The ultraviolet lamp 332 is vertically arranged in the quartz tube 331. Since the housing 31 is arranged in a cylindrical structure, and the ultraviolet lamp 332 is vertically arranged in the quartz tube 331, it can be ensured that the ultraviolet light emitted by the ultraviolet lamp 332 can fully cover the photocatalytic plate 32, effectively increasing the contact area between light and the photocatalyst.

[0053] See also Figure 5A drug inlet is provided at the upper end of the shell 31, and the drug inlet is connected to the drug supply component 34. The drug supply component 34 includes a drug tank 341, a drug supply pump 342, a drug supply valve 343 and a drug supply flow meter 344. The drug inlet is connected to the drug tank 341 through the drug supply pump 342. The drug supply valve 343 and the drug supply flow meter 344 are provided between the drug supply pump 342 and the shell 31. The drug tank 341 stores hydrogen peroxide.

[0054] During operation, sewage enters the housing 31 from the inlet, and hydrogen peroxide enters the housing 31 from the drug inlet, so that the pH value of the sewage in the housing 31 is adjusted to 4. When the ultraviolet light emitted by the ultraviolet lamp irradiates the photocatalytic plate 32, under the photocatalytic effect and acidic conditions, the hydrogen peroxide is decomposed to produce hydroxyl radicals (·OH) with extremely strong oxidizing ability. The hydroxyl radicals can attack and destroy the molecular structure of the pollutants, causing them to be oxidized and decomposed into harmless or low-toxic substances.

[0055] See also Figure 1 The sewage treatment system 100 further includes a pumping pump 70 . The bottom side end of the shell 31 is provided with an outlet, and the outlet is connected to the separation device 40 through the pumping pump 70 .

[0056] See also Figure 1 The separation device 40 is used to separate the solid and liquid of the sewage after the enhanced oxidation treatment, and usually uses sedimentation, filtration or centrifugation to remove the precipitate or suspended matter generated in the three-dimensional electrode catalytic oxidation device 20 and the strong oxidation device 30.

[0057] See also Figure 1 The sewage treatment system 100 further includes a water tank 110 , which is connected to the separation device 40 . The liquid of the sewage after the enhanced oxidation treatment after solid-liquid separation in the separation device 40 enters the water tank 110 .

[0058] See also Figure 1 , Figure 2 and Figure 5 The sewage treatment system 100 also includes a pH sensor and a controller. The number of the pH sensors is two, including a first pH sensor 15 and a second pH sensor 35. The first pH sensor 15 is arranged in the regulating tank 11, and the second pH sensor 35 is arranged in the shell 31. The first pH sensor 15 and the second pH sensor 35 are both communicatively connected to the controller, and the drug supply pump 342, the pumping pump 70 and the two dosing pumps 142 are electrically connected to the controller.

[0059] See also Figure 1 , Figure 2 and Figure 5The controller controls the two dosing pumps 142 to work according to the pH value detected by the first pH sensor 15, so as to automatically adjust the pH value of the sewage in the regulating tank 11 to 7, thereby providing more stable water quality for subsequent sewage treatment, effectively reducing the corrosion effect of sewage on the pipeline, and effectively extending the service life of each pipeline in the sewage treatment system 100.

[0060] Before the strong oxidation device 30 works, the controller controls the drug supply pump 342 to work according to the pH value detected by the second pH sensor 35, so as to automatically adjust the pH value of the sewage in the shell 31 to 4, thereby dynamically adjusting the amount of hydrogen peroxide added, effectively improving the sewage treatment effect, and controlling the sewage treatment cost.

[0061] During the operation of the strong oxidation device 30, the controller controls the pumping pump 70 to operate according to the pH value detected by the second pH sensor 35 to determine whether the reaction in the housing 31 is completed. Generally speaking, when the pH value detected by the second pH sensor 35 is close to 7, it can be determined that the reaction in the housing 31 is completed, that is, the strong oxidation treatment step is completed, and the controller controls the pumping pump 70 to operate to send the sewage after the enhanced oxidation treatment into the separation device 40.

[0062] See also Figure 1 The sewage treatment system 100 also includes a water quality detector 120, an output pump 80 and a switching valve 90. The water quality detector 120 is arranged in the water storage tank 110. The water quality detector 120 is communicatively connected with the controller. The output pump 80 is connected with the water storage tank 110. The inlet of the switching valve 90 is connected with the output pump 80. One outlet of the switching valve 90 is connected with an external connecting pipe, and the other outlet of the switching valve 90 is connected with the water inlet pipe 26. The output pump 80 and the switching valve 90 are both electrically connected with the controller.

[0063] When the water quality information detected by the water quality detector 120 meets the requirements, the controller controls the output pump 80 to work and switches the switching valve 90 to connect the water storage tank 110 with the external connecting pipe. Through the external connecting pipe, the liquid can be discharged or enter the biological filter tank for deep treatment.

[0064] When the water quality information detected by the water quality detector 120 does not meet the requirements, the controller controls the output pump 80 to work and switches the switching valve 90 to connect the water storage tank 110 with the water inlet pipe 26, so that the water in the water storage tank 110 can re-enter the three-dimensional electrode catalytic device and the strong oxidation device 30 for treatment. In this way, the sewage treatment system 100 has a higher degree of automation, is more convenient for operators to operate, and has a good sewage treatment effect.

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

[0066] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A sewage treatment system, characterized in that: include, A pretreatment device for pre-treating sewage; A three-dimensional electrode catalytic oxidation device, used for photoelectric oxidation treatment of pretreated sewage; the three-dimensional electrode catalytic oxidation device is connected to the pretreatment device, and the three-dimensional electrode catalytic oxidation device includes a shell, an anode electrode plate, a cathode electrode plate, a particle electrode assembly and a light source assembly, the anode electrode plate and the cathode electrode plate are arranged in the shell, the particle electrode assembly is arranged between the anode electrode plate and the cathode electrode plate, an accommodation space is arranged between the anode electrode plate, the cathode electrode plate and the particle electrode assembly, the light source assembly is arranged in the accommodation space, and the surfaces of the cathode electrode plate and the particle electrode assembly are coated with a photocatalytic coating, and the photocatalytic coating has a photocatalyst; A strong oxidation device, used for strong oxidation treatment of sewage after photoelectric oxidation treatment; the strong oxidation device is connected to the three-dimensional electrode catalytic oxidation device; as well as The separation device is used for separating the solid and liquid of the sewage after the strong oxidation treatment, and the separation device is connected with the strong oxidation device.

2. The sewage treatment system according to claim 1, characterized in that: The particle electrode assembly comprises a particle electrode and a filling grid basket for containing the particle electrode. The filling grid basket is a frame basket made of a mesh plate, and the photocatalytic coating is coated on the surface of the filling grid basket.

3. The sewage treatment system according to claim 2, characterized in that: The particle electrode is columnar activated carbon, the diameter of the activated carbon is 2-3mm, and the height is 5-6mm; the mesh holes of the mesh plate are 2mm*2mm.

4. The sewage treatment system according to claim 3, characterized in that: The light source assembly includes a quartz tube and an ultraviolet lamp. The quartz tube is vertically arranged in the accommodating space, the upper end of the quartz tube passes upward out of the shell, the bottom of the quartz tube is tightly connected to the shell, and the ultraviolet lamp is vertically arranged in the quartz tube.

5. The sewage treatment system according to claim 4, characterized in that: The three-dimensional electrode catalytic oxidation device also includes a water inlet pipe and an aeration pipe, which are arranged at the bottom of the shell. The water inlet pipe is connected to the pretreatment device, and the water inlet pipe is provided with water inlet holes along its length. The aeration pipe is connected to an external air pump, and the aeration pipe is provided with aeration holes along its length.

6. The sewage treatment system according to claim 1, characterized in that: The strong oxidation device includes a shell, a photocatalytic plate, an ultraviolet light source assembly and a drug supply assembly. The shell is arranged in a cylindrical structure, the photocatalytic plate is fixedly arranged on the circumferential inner wall of the shell, the ultraviolet light source assembly is arranged in the middle of the shell, and a drug inlet is arranged on the upper end of the shell, and the drug inlet is connected to the drug supply assembly.

7. The sewage treatment system according to claim 6, characterized in that: The material of the photocatalytic plate is metallic titanium. The surface of the photocatalytic plate is coated with a photocatalytic coating, and the photocatalytic coating contains a photocatalyst.

8. The sewage treatment system according to claim 1 or 7, characterized in that: The photocatalyst is modified titanium dioxide doped with trivalent iron ions or modified titanium dioxide doped with conductive graphene.

9. The sewage treatment system according to claim 6, characterized in that: The drug supply assembly includes a drug tank, a drug supply pump, a drug supply valve and a drug supply flow meter. The drug inlet is connected to the drug tank through the drug supply pump. The drug supply valve and the drug supply flow meter are arranged between the drug supply pump and the outer shell. The drug tank stores hydrogen peroxide.

10. The sewage treatment system according to claim 9, characterized in that: It also includes a water tank, a water quality detector, an output pump, a switching valve and a controller. The water tank is connected to the separation device, the water quality detector is arranged in the water tank, the inlet of the switching valve is connected to the water tank, one outlet of the switching valve is connected to an external connecting pipe, the other outlet of the switching valve is connected to the three-dimensional electrode catalytic oxidation device, the water quality detector is communicatively connected to the controller, and the output pump and the switching valve are electrically connected to the controller.

Images