Multi-section Fenton tower for high-concentration wastewater pretreatment

Abstract

The multi-section Fenton tower comprises a first tower body, a second tower body and a third tower body, a water storage tank is arranged on one side of the first tower body, a first dosing assembly is arranged outside the water storage tank, a second dosing assembly is arranged inside the first tower body, and a third dosing assembly is arranged inside the second tower body. By deeply optimizing the dosing process, the ineffective loss of hydrogen peroxide is successfully reduced. Specifically, the system intelligently calculates and accurately controls the adding amount of hydrogen peroxide according to the concentration and type of pollutants in wastewater. According to the measure, the treatment effect is ensured, meanwhile, the dosage of hydrogen peroxide and ferrous iron is remarkably reduced, the treatment cost is reduced, and in order to further improve the removal effect of pollutants in the wastewater, an efficient catalyst is introduced into the multi-section Fenton tower. The catalyst can accelerate the Fenton reaction speed and improve the generation efficiency of hydroxyl radicals, thereby further enhancing the degradation ability to pollutants.

Description

Technical Field

[0001] The utility model relates to the technical field of multi-section Fenton towers, in particular to a multi-section Fenton tower for pre-treating high-concentration wastewater. Background Art

[0002] In recent years, the discharge of industrial wastewater has increased dramatically with the rapid growth of industrial development. The high concentrations of pollutants in these wastewaters, such as COD, ammonia nitrogen, total nitrogen, total phosphorus, heavy metals, and the high salinity in some wastewaters, have posed a great threat to the environment and pose potential risks to aquatic ecosystems and human health.

[0003] Traditional biochemical treatment methods are inadequate for treating high-concentration industrial wastewater, with limited effectiveness. Therefore, advanced oxidation technologies, particularly Fenton oxidation, have garnered widespread attention as effective wastewater treatment technologies. Fenton oxidation generates highly oxidizing hydroxyl radicals, which degrade organic pollutants in wastewater, achieving water purification. However, in practical applications, Fenton oxidation also faces numerous challenges. Fenton oxidation requires large amounts of hydrogen peroxide and ferrous ions as reagents, but reagent utilization is often low, leading to increased treatment costs. In high-concentration wastewater, pollutants are numerous and concentrated, resulting in low hydraulic exchange efficiency, which affects the reaction rate and effectiveness of Fenton oxidation. Due to the high pollutant content in wastewater and the difficulty of some pollutants to be completely degraded by hydroxyl radicals, treatment times are long, making it difficult to meet the demand for rapid treatment. To overcome these shortcomings, a multi-stage Fenton tower was proposed for the pretreatment of high-concentration wastewater. Utility Model Content

[0004] In view of the deficiencies in the prior art, the present invention provides a multi-section Fenton tower for pretreatment of high-concentration wastewater, which is used to solve the above problems.

[0005] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A multi-section Fenton tower for pretreatment of high-concentration wastewater comprises a first tower body, a second tower body and a third tower body, a water reservoir being provided on one side of the first tower body, a first dosing assembly being provided on the outside of the water reservoir, a second dosing assembly being provided on the inside of the first tower body, a third dosing assembly being provided on the insides of the first and second tower bodies, a connecting assembly being provided between the first, second and third tower bodies, a filter plate being fixedly connected to the insides of the first and second tower bodies, three support blocks being provided on the insides of the first and second tower bodies, two of the support blocks being fixedly connected to the top and bottom of the filter plate located inside the first tower body, and another support block being fixedly connected to the top of the filter plate located inside the second tower body, and the connecting pipes at the bottoms of the first, second and third tower bodies being connected to a backwash inlet pipe and a backwash outlet pipe on the outsides.

[0007] Preferably, a catalyst filler is provided inside the third tower body, and an inspection port is provided outside the third tower body.

[0008] Preferably, one side of the first tower body, the second tower body and the third tower body are all connected to a second water inlet pipe, and the other side of the first tower body, the second tower body and the third tower body are all connected to a water outlet pipe.

[0009] Preferably, the first dosing component includes an acid barrel and an alkali barrel arranged on one side of the water reservoir, the tops of the acid barrel and the alkali barrel are connected to a delivery pipe, the other end of the delivery pipe is connected to the outside of the water reservoir, and a pH meter is provided inside the water reservoir.

[0010] Preferably, the connecting assembly includes a first water inlet pipe connected to one side of the water reservoir, the other end of the first water inlet pipe is connected to the connecting pipe at the bottom of the first tower body, the outside of the first water inlet pipe is connected to a first return pipe, the other end of the first return pipe is connected to the outside of the second water inlet pipe, the water outlet pipe of the first tower body is connected to a third water inlet pipe, the other end of the third water inlet pipe is connected to the connecting pipe at the bottom of the second tower body, the outside of the third water inlet pipe is connected to a second return pipe, the other end of the second return pipe is connected to the outside of the second water inlet pipe of the second tower body, the outside of the water outlet pipe of the second tower body is connected to a fourth water inlet pipe, the other end of the fourth inlet pipe is connected to the connecting pipe at the bottom of the third tower body, the outside of the fourth water inlet pipe is connected to the third return pipe, the other end of the third return pipe is connected to the outside of the second water inlet pipe of the third tower body, a reflux pump is provided on the outside of the first return pipe, the second return pipe and the third return pipe, and a water inlet pump is provided on the outside of the first water inlet pipe, the third water inlet pipe and the fourth water inlet pipe.

[0011] Preferably, the second dosing component includes a ferrous barrel arranged on the top of the first tower body, the bottom of the ferrous barrel is connected to a first dosing pipe, the first dosing pipe extends to the bottom of the filter plate, one end of the first dosing pipe is connected to a first drug distribution pipe, and the first drug distribution pipe is fixedly connected to the support block.

[0012] Preferably, the third dosing component includes a hydrogen peroxide barrel arranged on the top of the first tower body and the second tower body, and the bottom of the hydrogen peroxide barrel is connected to two symmetrically distributed second dosing pipes, and the two second dosing pipes extend to the interior of the first tower body and the second tower body respectively. One end of the second dosing pipe is connected to a second medicine distribution pipe, and the second medicine distribution pipe is fixedly connected to the support block.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: the multi-stage Fenton tower of the present application adopts an optimized water inlet and water distribution system to ensure that the wastewater can be evenly distributed when entering the reaction tower. This design effectively increases the contact area and contact time between the wastewater and the hydroxyl radicals, greatly shortens the residence time of the wastewater in the tower, and improves the treatment efficiency. Through in-depth optimization of the dosing process, the ineffective loss of hydrogen peroxide has been successfully reduced. Specifically, the system intelligently calculates and accurately controls the dosage of hydrogen peroxide according to the concentration and type of pollutants in the wastewater. While ensuring the treatment effect, this measure significantly reduces the dosage of hydrogen peroxide and ferrous iron, and reduces the treatment cost. In order to further improve the removal effect of pollutants in wastewater, the present invention introduces a high-efficiency catalyst into the multi-stage Fenton tower. This catalyst can accelerate the speed of the Fenton reaction, improve the efficiency of the generation of hydroxyl radicals, and thus further enhance the ability to degrade pollutants. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a three-dimensional structural diagram of the utility model;

[0015] Figure 2 This is a schematic diagram of the structure of the utility model

[0016] Figure 3 For this utility model Figure 2 Schematic diagram of the structure of part A.

[0017] In the figure: 1. first tower body; 2. second tower body; 3. third tower body; 4. acid barrel; 5. alkali barrel; 6. delivery pipe; 7. water reservoir; 8. pH meter; 9. water inlet pump; 10. first water inlet pipe; 11. first reflux pipe; 12. reflux pump; 13. second water inlet pipe; 14. ferrous barrel; 15. first dosing pipe; 16. first drug distribution pipe; 17. support block; 18. filter plate; 19. hydrogen peroxide barrel; 20. second dosing pipe; 21. second drug distribution pipe; 22. backwash inlet pipe; 23. backwash outlet pipe; 24. catalyst filler; 25. inspection port; 26. third water inlet pipe; 27. fourth water inlet pipe; 28. second reflux pipe; 29. ​​third reflux pipe; 30. outlet pipe. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0019] Example: Refer to Figure 1-3A multi-stage Fenton tower for pretreatment of high-concentration wastewater includes a first tower body 1, a second tower body 2 and a third tower body 3. A water reservoir 7 is provided on one side of the first tower body 1. A first dosing component is provided on the outside of the water reservoir 7. A second dosing component is provided inside the first tower body 1. A third dosing component is provided inside the first tower body 1 and the second tower body 2. A connecting component is provided between the first tower body 1, the second tower body 2 and the third tower body 3. A filter plate 18 is fixedly connected to the inside of the first tower body 1 and the second tower body 2. Three support blocks 17 are provided inside the first tower body 1 and the second tower body 2, wherein the outsides of two support blocks 17 are fixedly connected to the top and bottom of the filter plate 18 located inside the first tower body 1, and the other support block 17 is fixedly connected At the top of the filter plate 18 located inside the second tower body 2, the outsides of the connecting pipes at the bottom of the first tower body 1, the second tower body 2 and the third tower body 3 are connected with a backwash water inlet pipe 22 and a backwash water outlet pipe 23, the interior of the third tower body 3 is provided with a catalyst filler 24, the outside of the third tower body 3 is provided with an inspection port 25, one side of the first tower body 1, the second tower body 2 and the third tower body 3 are connected with a second water inlet pipe 10, the other side of the first tower body 1, the second tower body 2 and the third tower body 3 are connected with a water outlet pipe 30, the first dosing assembly includes an acid barrel 4 and an alkali barrel 5 arranged on one side of the water reservoir 7, the tops of the acid barrel 4 and the alkali barrel 5 are connected with a delivery pipe 6, the other end of the delivery pipe 6 is connected to the outside of the water reservoir 7, and the interior of the water reservoir 7 is provided with a pH meter 8. The connecting assembly includes a first water inlet pipe 10 connected to one side of the water reservoir 7, the other end of the first water inlet pipe 10 is connected to the connecting pipe at the bottom of the first tower body 1, the outside of the first water inlet pipe 10 is connected to the first return pipe 11, the other end of the first return pipe 11 is connected to the outside of the second water inlet pipe 13, the outlet pipe 30 of the first tower body 1 is connected to the third water inlet pipe 26, the other end of the third water inlet pipe 26 is connected to the connecting pipe at the bottom of the second tower body 2, the outside of the third water inlet pipe 26 is connected to the second return pipe 28, the other end of the second return pipe 28 is connected to the outside of the second water inlet pipe 13 of the second tower body 2, the outside of the water outlet pipe 30 of the second tower body 2 is connected to the fourth water inlet pipe 27, the other end of the fourth water inlet pipe 27 is connected to the outside of the third tower body 3 On the connecting pipe, the outside of the fourth water inlet pipe 27 is connected to the third return pipe 29, and the other end of the third return pipe 29 is connected to the outside of the second water inlet pipe 13 of the third tower body 3. The first return pipe 11, the second return pipe 28 and the third return pipe 29 are all provided with a reflux pump 12 on the outside, and the first water inlet pipe 10, the third water inlet pipe 26 and the fourth water inlet pipe 27 are all provided with a water inlet pump 9 on the outside. The second dosing component includes a ferrous barrel 14 arranged on the top of the first tower body 1, and the bottom of the ferrous barrel 14 is connected to the first dosing pipe 15, which extends to the bottom of the filter plate 18. One end of the first dosing pipe 15 is connected to the first drug distribution pipe 16, and the first drug distribution pipe 16 is fixedly connected to the support block 17. The third dosing component,The system includes a hydrogen peroxide tank 19 mounted on top of the first tower body 1 and the second tower body 2. The bottom of the hydrogen peroxide tank 19 is connected to two symmetrically distributed second dosing pipes 20. The two second dosing pipes 20 extend into the interior of the first tower body 1 and the second tower body 2, respectively. One end of each second dosing pipe 20 is connected to a second drug dispensing pipe 21, which is fixedly connected to the support block 17.

[0020] During use: after the production wastewater enters the water reservoir 7, the pH value of the wastewater is measured by the pH meter 8 arranged inside the water reservoir 7, and the pH value of the wastewater is controlled to 3-3.5 by adding acid or alkali. The wastewater after adjusting the pH is pumped into the interior of the first tower body 1 through the water inlet pump 9 along the first water inlet pipe 10. The bottom of the first tower body 1 is connected to the connecting pipe. After the water enters the interior of the first tower body 1, it passes through the filter plate 18 arranged at the bottom of the first tower body 1. The filter plate 18 is circular with an opening on the outer edge and a hole inside the filter plate 18. The size and size of the hole are determined according to the amount of water inflow. Generally, two rows of holes are opened, and the center of the filter plate 18 is not opened. Since the hole of the filter plate 18 is small, the flow rate through the hole is accelerated after the water enters, and the empty tower flow rate is increased, which can effectively improve the water inflow. High hydraulic exchange ensures full contact between pollutants and the hydroxyl radicals generated by the Fenton column, improving removal efficiency and shortening residence time. A second drug distribution tube 21 and a first drug distribution tube 16 are arranged above and below the filter plate 18, respectively. The first and second drug distribution tubes 16 and 21 are connected to the filter plate 18 via support blocks 17. The first and second drug distribution tubes 16 and 21 are annular, their dimensions determined by the filter plate openings. The centerlines of the first and second drug distribution tubes 16 and 21 align with the centerlines of the two rows of openings in the filter plate 18, facilitating contact between the drug and the incoming water. Compared to traditional drug distribution methods, this design facilitates more rapid and thorough mixing of the drug. When wastewater enters the Fenton column from the bottom, it flows smoothly, with a low flow rate and relatively uniform pressure distribution. When the filter plate openings are opened, the flow area decreases. According to Bernoulli's principle, the water velocity increases due to the confinement of the narrow area. This is because the law of conservation of flow (the embodiment of the law of conservation of mass in fluids) requires that the volume of fluid passing through the narrow area per unit time remain constant, so the flow rate must increase. The increase in flow rate leads to a decrease in pressure, forming a pressure difference. This pressure difference forms a low-pressure area below the filter plate 18, which acts like a "suction" to suck the ferrous agent into the water flow. This is because the ferrous agent is subjected to a greater pressure in the higher-pressure area, and a smaller pressure in the lower-pressure area (i.e., below the filter plate). Therefore, the ferrous agent will move to the low-pressure area and quickly mix with the water flow. When the water flows through the filter plate, due to changes in flow rate and pressure, the water flow will become unstable and form turbulence. Turbulence is a complex flow state in which the fluid The speed and direction are constantly changing. This instability increases the frequency of collisions between the fluid and the hydrogen peroxide reagent, allowing the two to mix quickly. Compared with conventional Fenton reaction devices, the filter plate 18, as a key component, has changed the traditional way of mixing wastewater and reagents. The filter plate 18 is not only used for filtering, but more importantly, its design and layout achieve uniform distribution of the reagent in the wastewater, avoiding the use of a stirring device. At the same time, when the wastewater flows through the filter plate 18, due to the action of the filter plate 18, the wastewater and the reagent are effectively mixed, thereby improving the reaction efficiency.

[0021] During the Fenton process, the total hydrogen peroxide dosage is a (hydrogen peroxide:COD) mass ratio of 0.5 to 5:1, and the ferrous iron dosage is a (hydrogen peroxide:ferrous iron) molar ratio of 5 to 20:1. The hydrogen peroxide dosage in the first tower body 1 is controlled to be 1 / 2 of the total dosage, while the ferrous iron dosage is the entire dosage. The staged addition of hydrogen peroxide effectively avoids the waste and ineffectiveness of the reagents caused by adding too much hydrogen peroxide at once. An external circulation pipe is set in the first tower body 1 to achieve sufficient exchange and mixing of wastewater in the tower, thereby improving the wastewater treatment effect. The reflux ratio is controlled at 0.5-2, and the residence time of the first tower body 1 is 20-120 minutes. The reflux can also effectively reduce the amount of ferrous iron added. In the Fenton reaction, some trivalent iron will be reduced to ferrous iron. By setting up a reflux pipe, this reduced ferrous iron can be pumped back to the bottom of the Fenton tower to continue reacting with fresh hydrogen peroxide, thereby reducing the amount of ferrous iron added from the outside. Reducing the external ferrous iron addition not only saves costs, but also, since ferrous iron is one of the main reagents in the Fenton reaction, its reduction also means reducing the amount of subsequent sludge generated. This is because the reaction of ferrous iron with hydrogen peroxide will produce some solid precipitates, which will increase the total amount of sludge.

[0022] The second tower body 2 is generally the same as the first tower body 1. In particular, the ferrous medicine distribution pipe and the ferrous medicine dosing pipe are reduced. The outlet water of the first tower body 1 enters the second tower body 2 through the pipeline, and the remaining hydrogen peroxide agent is added to start the reaction. The residence time in the second tower body 2 is 20 to 120 minutes.

[0023] The third tower body 3 is free of drug distribution and dosing pipes. Instead, it is filled with a Fenton catalyst at a ratio of 1:3-5 between the catalyst filling volume and the tower's effective volume. An inspection port is provided within the third tower body 3 to facilitate packing replacement and internal tower maintenance. The effluent from the second tower body 2 flows through a pipeline into the third tower body 3, where it remains for 15-60 minutes.

[0024] Fenton towers are equipped with a backwash system. After a period of use, the backwash water pump is turned on to clean the inside of the Fenton tower. The backwash water is discharged from the backwash outlet and collected and discharged into the collection tank.

[0025] The bottom of the Fenton tower is set to be conical to avoid dirt accumulation during the reaction and backwash process, forming dead corners that are difficult to clean and affecting subsequent use and water output.

[0026] To avoid corrosion to the device caused by long-term contact with ferrous iron and hydrogen peroxide, the Fenton tower is made of 316 stainless steel and sprayed with anti-corrosion paint.

[0027] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0028] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-stage Fenton tower for pretreatment of high-concentration wastewater, comprising a first tower body (1), a second tower body (2) and a third tower body (3), characterized in that: A water reservoir (7) is provided on one side of the first tower body (1), a first dosing assembly is provided outside the water reservoir (7), a second dosing assembly is provided inside the first tower body (1), a third dosing assembly is provided inside the first tower body (1) and the second tower body (2), a connecting assembly is provided between the first tower body (1), the second tower body (2) and the third tower body (3), a filter plate (18) is fixedly connected inside the first tower body (1) and the second tower body (2), and the first tower body (1) and the second tower body (2) are fixedly connected. Three support blocks (17) are provided inside the first tower body (1) and the second tower body (2), wherein the outsides of two support blocks (17) are fixedly connected to the top and bottom of a filter plate (18) located inside the first tower body (1), and the other support block (17) is fixedly connected to the top of the filter plate (18) located inside the second tower body (2), and the outsides of the connecting pipes at the bottoms of the first tower body (1), the second tower body (2) and the third tower body (3) are all connected to a backwash water inlet pipe (22) and a backwash water outlet pipe (23).

2. The multi-stage Fenton tower for high-concentration wastewater pretreatment according to claim 1, characterized in that: A catalyst filler (24) is provided inside the third tower body (3), and an inspection port (25) is provided outside the third tower body (3).

3. The multi-stage Fenton tower for high-concentration wastewater pretreatment according to claim 1, characterized in that: One side of the first tower body (1), the second tower body (2) and the third tower body (3) are all connected to a second water inlet pipe (13), and the other side of the first tower body (1), the second tower body (2) and the third tower body (3) are all connected to a water outlet pipe (30).

4. The multi-stage Fenton tower for high-concentration wastewater pretreatment according to claim 1, characterized in that: The first dosing component comprises an acid barrel (4) and an alkali barrel (5) arranged on one side of a water reservoir (7); the tops of the acid barrel (4) and the alkali barrel (5) are both connected to a delivery pipe (6); the other end of the delivery pipe (6) is connected to the outside of the water reservoir (7); and a pH meter (8) is arranged inside the water reservoir (7).

5. The multi-stage Fenton tower for high-concentration wastewater pretreatment according to claim 1, characterized in that: The connecting assembly comprises a first water inlet pipe (10) connected to one side of the water reservoir (7), the other end of the first water inlet pipe (10) being connected to a connecting pipe at the bottom of the first tower body (1), the outside of the first water inlet pipe (10) being connected to a first return pipe (11), the other end of the first return pipe (11) being connected to the outside of a second water inlet pipe (13), the water outlet pipe (30) of the first tower body (1) being connected to a third water inlet pipe (26), the other end of the third water inlet pipe (26) being connected to the connecting pipe at the bottom of the second tower body (2), the outside of the third water inlet pipe (26) being connected to a second return pipe (28), the other end of the second return pipe (28) being connected to the second tower body (2) The outside of the second water inlet pipe (13) of the second tower body (2) is connected to the outside of the water outlet pipe (30), the outside of the second tower body (2) is connected to a fourth water inlet pipe (27), the other end of the fourth water inlet pipe (27) is connected to the connecting pipe at the bottom of the third tower body (3), the outside of the fourth water inlet pipe (27) is connected to a third return pipe (29), the other end of the third return pipe (29) is connected to the outside of the second water inlet pipe (13) of the third tower body (3), a return pump (12) is provided on the outside of the first return pipe (11), the second return pipe (28) and the third return pipe (29), and a water inlet pump (9) is provided on the outside of the first water inlet pipe (10), the third water inlet pipe (26) and the fourth water inlet pipe (27).

6. The multi-stage Fenton tower for high-concentration wastewater pretreatment according to claim 1, characterized in that: The second dosing assembly comprises a ferrous barrel (14) arranged on the top of the first tower body (1); the bottom of the ferrous barrel (14) is connected to a first dosing pipe (15); the first dosing pipe (15) extends to the bottom of the filter plate (18); one end of the first dosing pipe (15) is connected to a first drug distribution pipe (16); the first drug distribution pipe (16) is fixedly connected to a support block (17).

7. The multi-stage Fenton tower for high-concentration wastewater pretreatment according to claim 1, characterized in that: The third dosing component comprises a hydrogen peroxide bucket (19) arranged on the top of the first tower body (1) and the second tower body (2); the bottom of the hydrogen peroxide bucket (19) is connected to two symmetrically distributed second dosing pipes (20); the two second dosing pipes (20) extend to the interior of the first tower body (1) and the second tower body (2), respectively; one end of each of the second dosing pipes (20) is connected to a second drug dispensing pipe (21); and the second drug dispensing pipe (21) is fixedly connected to the support block (17).

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