Photofenton organic wastewater treatment device

Abstract

The present application relates to the field of wastewater treatment, in particular to a kind of photo-Fenton organic wastewater treatment device.The device includes fenton reaction zone and comprehensive oxidation zone, fenton reaction zone is provided with venturi type water inlet pipe, sieve hole plate, reduction bucket and cross-zone main pipe, at least one ultraviolet lamp is arranged in the space between adjacent two layers of sieve hole plate, the surface of sieve hole plate is provided with catalyst, multiple iron mesh are arranged in reduction bucket, and throat of venturi type water inlet pipe is communicated by reflux pipe;Electrode assembly and branch pipe are arranged in comprehensive oxidation zone, electrode assembly includes anode and cathode distributed in the two sides of branch pipe, anode is hollow structure, filled with conductive fiber inside, top end is provided with water injection pipe, and multiple sieve holes are arranged on the side of branch pipe, cross-zone main pipe extends into comprehensive oxidation zone, branch pipe is communicated with cross-zone main pipe, and water outlet hole is arranged on the side of anode, and anode is wound with insulating fiber loaded with activator.The present application can carry out multiple oxidation to organic wastewater, so that organic matter is fully oxidized and removed.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment, and more specifically to a photo-Fenton organic wastewater treatment device. Background Technology

[0002] Industries such as coking, electroplating, pharmaceuticals, printing and dyeing, leather, and papermaking all generate organic wastewater. Efficient treatment of organic wastewater is a goal pursued in the field of wastewater treatment.

[0003] The traditional Fenton process utilizes the chain reaction between ferrous ions and hydrogen peroxide to catalyze the generation of hydroxyl radicals, exhibiting strong oxidizing power. Its oxidation potential is second only to fluorine, reaching as high as 2.80 eV. It is particularly suitable for the oxidation treatment of organic wastewater that is difficult to biodegrade or where conventional chemical oxidation is ineffective. Photo-Fenton technology is an advanced oxidation water treatment technology that utilizes the enhanced effect of light radiation to generate hydroxyl radicals from H₂O₂, thereby treating organic matter.

[0004] However, existing photo-Fenton technology has not yet fully solved the problem of iron ion recycling, and there is no complete set of related equipment. Often, multiple devices are connected in series to form a local reflux process to reuse iron ions, but the recycling effect is not ideal. The remaining iron ions still need to be further adjusted for pH and precipitated, which requires a lot of reagents and operating costs.

[0005] CN114634265A discloses a photo-Fenton process for treating recalcitrant organic wastewater. The process includes: first, raw water is gravity-fed to an equalization tank to adjust the pH to 3-5, then enters a high-efficiency mixing tank; in the high-efficiency mixing tank, the reagent and wastewater are thoroughly mixed under the action of swirling aeration and stirring before entering the oxidation reaction zone; in the oxidation reaction zone, the reagent is uniformly mixed, and the chain reaction between ferrous ions and H₂O₂ catalyzes the generation of ·OH; most of the ferrous ions have been converted to ferric ions, and then the wastewater is returned to the system and flows through a UV photocatalytic reactor; under the excitation of high-intensity UV light quanta, the ferric ions are converted back to ferrous ions, and then returned to the second step for reuse; after neutralization, the wastewater enters a high-density sedimentation tank for solid-liquid separation, and finally, the effluent meets discharge standards. This invention utilizes ultraviolet light to reduce ferric ions, but the efficiency is extremely low or even ineffective. Ultraviolet light has strong energy, which can give electrons the energy to escape the atomic nucleus, causing the atom to lose electrons and be oxidized; however, it is difficult to provide electrons to iron to reduce it. Even if reduction is achieved, the effect is very poor, and a continuous supply of hydrogen peroxide is required to maintain the Fenton reaction. However, the difficulty in transporting hydrogen peroxide greatly increases the process cost.

[0006] Therefore, there is an urgent need to design an organic wastewater treatment device with a simpler processing flow and structure, and which can remove organic matter more efficiently. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a photo-Fenton organic wastewater treatment device, which can perform multiple oxidations on organic wastewater, thereby fully oxidizing and removing organic matter, and has a simple structure and operation process.

[0008] To solve the above-mentioned technical problems, the technical solution of the present invention is: a photo-Fenton organic wastewater treatment device, comprising:

[0009] The Fenton reaction zone is arranged from top to bottom as follows: a Venturi tube-shaped water inlet pipe, at least three layers of perforated plates, a reduction tank, and a cross-zone main pipe. At least one ultraviolet lamp is arranged in the space between two adjacent layers of perforated plates. The surface of the perforated plates that can be irradiated by the ultraviolet lamp is provided with a catalyst. Multiple iron mesh sheets are arranged from the first end to the second end in the reduction tank. The first end is an open end, and the second end is connected to the throat of the Venturi tube-shaped water inlet pipe through a return pipe.

[0010] The integrated oxidation zone contains at least one electrode assembly and at least one branch pipe. The electrode assembly includes an anode and a cathode distributed on both sides of the branch pipe. The anode is a hollow structure filled with conductive fibers and has a water injection pipe at its top. Multiple sieve holes are provided on the side facing the branch pipe. The cross-zone main pipe extends into the integrated oxidation zone. The branch pipe is connected to the cross-zone main pipe and has a water outlet on the side facing the anode. The branch pipe is wound with insulating fibers loaded with activator.

[0011] Furthermore, to facilitate sedimentation, a sedimentation cone groove is provided at the bottom of the comprehensive oxidation zone.

[0012] Furthermore, in order to allow for the periodic discharge of sediment, the sedimentation cone is connected to a drain pipe, and the drain pipe is equipped with a valve for controlling the discharge.

[0013] Furthermore, the catalyst is a sulfur-functionalized polymer.

[0014] Furthermore, the preparation method of the sulfur functionalized polymer is as follows:

[0015] The product was obtained by reacting terephthalaldehyde, 2-thiobarbituric acid and p-phenylenediamine as precursors in an aqueous medium.

[0016] The product was calcined in an argon atmosphere, and sulfur-functionalized polymers were prepared by dehydration reaction between aldehyde and amino groups.

[0017] Furthermore, the activator includes at least one of copper oxide, manganese oxide, and zinc oxide.

[0018] Furthermore, the wavelength of the ultraviolet light emitted by the ultraviolet lamp is 420 nm.

[0019] Furthermore, the anode is made of titanium, and the cathode is made of iron.

[0020] Furthermore, in each electrode assembly, the distance between the anode and cathode is 10-15cm, and the power supply is 30-48V.

[0021] Furthermore, the branch pipe is plate-shaped.

[0022] By adopting the above technical solution, the present invention has the following beneficial effects:

[0023] (1) Light can simultaneously produce hydrogen peroxide and photocatalytic degradation. The produced hydrogen peroxide can also form a Fenton reaction with ferrous ions in the influent, fully oxidizing organic matter.

[0024] (2) It can automatically reduce iron ions and reuse them.

[0025] (3) By replenishing the saline solution through electrolysis, hydroxide ions can be obtained to precipitate and remove excess iron ions. During the precipitation process, organic pollutants can also be adsorbed and precipitated.

[0026] (4) The chlorine produced by electrolysis also has an oxidizing effect on organic matter. The activator loaded on the surface of the branch pipe catalyzes and activates chlorine and hypochlorite ions, which can fully oxidize organic matter.

[0027] (5) The device incorporates multiple oxidation processes, which can fully oxidize and remove organic matter within the device, resulting in significant effects.

[0028] (6) By utilizing the water distribution function of the branch pipe, the reaction electrode can be directly contacted to obtain a better precipitation effect. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of the photo-Fenton organic wastewater treatment device of the present invention;

[0030] Figure 2 This is a schematic diagram of the anode and branch pipe of the present invention;

[0031] In the diagram, 1. Fenton reaction zone; 2. Venturi tube inlet pipe; 3. Perforated sieve plate; 4. Reduction tank; 5. Main cross-zone pipe; 6. Ultraviolet lamp; 7. Iron mesh; 8. Return pipe; 9. Comprehensive oxidation zone; 10. Branch pipe; 11. Anode; 12. Cathode; 13. Conductive fiber; 14. Water injection pipe; 15. Insulating fiber; 16. Sedimentation cone; 17. Sewage pipe; 18. Valve; 19. Tank body; 20. Outlet. Detailed Implementation

[0032] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0033] like Figure 1 and Figure 2 As shown, a photo-Fenton organic wastewater treatment device includes:

[0034] The Fenton reaction zone 1 is provided with, from top to bottom, a Venturi tube-shaped water inlet pipe 2, at least three layers of perforated plates 3, a reduction tank 4, and a cross-zone main pipe 5. At least one ultraviolet lamp 6 is provided in the space between two adjacent layers of perforated plates 3. The surface of the perforated plates 3 that can be irradiated by the ultraviolet lamp 6 is provided with a catalyst, which can produce hydrogen peroxide under the irradiation of the ultraviolet lamp 6. Multiple iron mesh sheets 7 are arranged in sequence from the first end to the second end in the reduction tank 4. The second end of the reduction tank 4 is connected to the throat of the Venturi tube-shaped water inlet pipe 2 through a return pipe 8.

[0035] The integrated oxidation zone 9 contains at least one electrode assembly and at least one branch pipe 10. The electrode assembly includes an anode 11 and a cathode 12 distributed on both sides of the branch pipe 10. The anode 11 is a hollow structure filled with conductive fibers 13, and has a water injection pipe 14 at its top. Multiple sieve holes are provided on the side facing the branch pipe 10. Concentrated brine is injected from the water injection pipe 14 and seeps out from the sieve holes. Under the action of the electrode assembly, chloride ions lose electrons to generate chlorine gas. The cross-zone main pipe 5 extends into the integrated oxidation zone 9. The branch pipe 10 is connected to the cross-zone main pipe 5 and has a water outlet on the side facing the anode 11. The water outlet is covered with insulating fibers 15 loaded with activator. The insulating fibers 15 can be wound around the surface of the branch pipe 9. When water flows out from the branch pipe 9, it penetrates the surface of the insulating fibers 15 and comes into contact with the activator.

[0036] Among them, such as Figure 1 As shown, the Fenton reaction zone 1 and the comprehensive oxidation zone 9 are located within the same rectangular box 1. The box 1 is divided into the Fenton reaction zone 1 and the comprehensive oxidation zone 9, with the Fenton reaction zone 1 on the left and the comprehensive oxidation zone 9 on the right. Preferably, 3-8 layers of perforated sieve plates 3 are provided. Ultraviolet lamps 6 can be installed on the lower surface of all perforated sieve plates 3 except the bottom one, and catalysts are placed on the upper surface of all perforated sieve plates 3 except the top one.

[0037] In some embodiments, such as Figure 1 As shown, a sedimentation cone trough 16 is provided at the bottom of the comprehensive oxidation zone 9, and an outlet 20 is provided at the upper end.

[0038] In some embodiments, such as Figure 1 As shown, the sedimentation cone 16 is connected to a drain pipe 17, and the drain pipe 17 is equipped with a valve 18 for controlling the discharge of sewage.

[0039] In some embodiments, the catalyst is a sulfur-functionalized polymer. The preparation method of the sulfur-functionalized polymer can be as follows:

[0040] The product was obtained by reacting terephthalaldehyde, 2-thiobarbituric acid and p-phenylenediamine as precursors in an aqueous medium at 60°C.

[0041] The product was calcined under argon atmosphere, and sulfur-functionalized polymers were prepared through a dehydration reaction between the aldehyde and amino groups. Of course, other methods can also be used to obtain sulfur-functionalized polymers.

[0042] In some embodiments, the activator includes at least one of copper oxide, manganese oxide, and zinc oxide.

[0043] In some embodiments, the wavelength of the ultraviolet light irradiated by the ultraviolet lamp 6 is 420 nm. By irradiating the catalyst with the ultraviolet lamp 6 of this wavelength, hydrogen peroxide can be continuously obtained.

[0044] In some embodiments, the anode 11 is made of titanium and the cathode 12 is made of iron.

[0045] In some embodiments, in each electrode assembly, the distance between the anode 11 and the cathode 12 is 10-15 cm, and the power supply is 30-48V.

[0046] In some embodiments, the branch pipe 10 is flat, with the anode 11 and the cathode 12 on both sides of the plane.

[0047] The wastewater treatment process of the photo-Fenton organic wastewater treatment device involved in the above embodiments will be described in detail below.

[0048] During operation, the wastewater to be treated is pumped into the Venturi tube-shaped inlet pipe 2. The ultraviolet lamp 6 is turned on, and the electrode assembly is energized. A small amount of ferrous sulfate is added to the initial water. The dissolved ferrous ions and the catalyst react with the hydrogen peroxide obtained under the irradiation of the ultraviolet lamp 6 to form a Fenton reaction, degrading the organic matter in the influent. Some of the generated ferrous ions are drawn into the reduction tank 4 and undergo a redox reaction with the iron mesh 7 inside the reduction tank 4 to generate ferrous ions, which are then drawn into the Venturi tube-shaped inlet pipe 2 and re-enter the Fenton reaction zone 1. The remaining water enters the cross-zone main pipe 5 and flows out from the branch pipe 10, where the reaction continues between the anode 11 and cathode 12 of the electrode assembly. Concentrated brine enters the anode 11 through the water injection pipe 14 and seeps out from the anode 11, generating chlorine gas. The chlorine gas comes into contact with the activator loaded on the fiber surface of the branch pipe 10, activating the chlorine gas and generating various free radicals, which degrade organic matter. At the same time, hydroxide ions generated by the cathode 12 combine with iron ions in the water to form ferric hydroxide precipitate. During the precipitation process, some organic matter can also be adsorbed and particulate matter in the water can be flocculated to purify the water quality. The precipitate is collected in the sedimentation cone 16 and can be discharged periodically. The water that has undergone two oxidation processes can be discharged directly from the outlet 20.

[0049] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A photo-Fenton organic wastewater treatment device, characterized in that, include: The Fenton reaction zone (1) is provided with a Venturi tube-shaped water inlet pipe (2), at least three layers of perforated plates (3), a reduction tank (4) and a cross-zone main pipe (5) from top to bottom. At least one ultraviolet lamp (6) is provided in the space between two adjacent layers of perforated plates (3). The surface of the perforated plates (3) that can be irradiated by the ultraviolet lamp (6) is provided with a catalyst. Multiple iron mesh sheets (7) are provided in the reduction tank (4) from its first end to its second end. The first end is an open end, and the second end is connected to the throat of the Venturi tube-shaped water inlet pipe (2) through a return pipe (8). The integrated oxidation zone (9) is provided with at least one electrode assembly and at least one branch pipe (10). The electrode assembly includes an anode (11) and a cathode (12) distributed on both sides of the branch pipe (10). The anode (11) is a hollow structure filled with conductive fibers (13). A water injection pipe (14) is provided at the top. Multiple sieve holes are provided on the side facing the branch pipe (10). The cross-zone main pipe (5) extends into the integrated oxidation zone (9). The branch pipe (10) is connected to the cross-zone main pipe (5). A water outlet is provided on the side facing the anode (11). The branch pipe (10) is wound with insulating fibers (15) loaded with activator. The catalyst is a sulfur-functionalized polymer; the activator includes at least one of copper oxide, manganese oxide, and zinc oxide.

2. The photo-Fenton organic wastewater treatment device according to claim 1, characterized in that, The bottom of the comprehensive oxidation zone (9) is provided with a sedimentation cone (16).

3. The photo-Fenton organic wastewater treatment device according to claim 2, characterized in that, The sedimentation cone (16) is connected to a drain pipe (17), and the drain pipe (17) is equipped with a valve (18) for controlling the discharge of sewage.

4. The photo-Fenton organic wastewater treatment device according to claim 1, characterized in that, The method for preparing the sulfur functionalized polymer is as follows: The product was obtained by reacting terephthalaldehyde, 2-thiobarbituric acid and p-phenylenediamine as precursors in an aqueous medium. The product was calcined in an argon atmosphere, and sulfur-functionalized polymers were prepared by dehydration reaction between aldehyde and amino groups.

5. The photo-Fenton organic wastewater treatment device according to claim 1, characterized in that, The wavelength of the ultraviolet light irradiated by the ultraviolet lamp (6) is 420 nm.

6. The photo-Fenton organic wastewater treatment device according to claim 1, characterized in that, The anode (11) is made of titanium, and the cathode (12) is made of iron.

7. The photo-Fenton organic wastewater treatment device according to claim 1, characterized in that, In each electrode assembly, the distance between the anode (11) and the cathode (12) is 10-15cm, and the power supply is 30-48V.

8. The photo-Fenton organic wastewater treatment device according to claim 1, characterized in that, The branch pipe (10) is plate-shaped.

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