A high-efficiency and low-risk disinfection device for tail water of a sewage treatment plant

Abstract

A high-efficiency and low-risk disinfection device for wastewater treatment plant effluent includes: a disinfection tank with an inlet and an outlet on its sidewall, the outlet being positioned higher than the inlet, and the disinfection tank used to store and disinfect the effluent; a water circulation assembly connected to the inlet and outlet, used for the inflow and outflow of effluent from the disinfection tank; a dosing assembly including a storage tank, a dosing pump, and a dosing pipe, the storage tank storing peracetic acid solution, and the dosing pipe connecting the disinfection tank and the storage tank; and an ultraviolet lamp assembly suspended inside the disinfection tank, used to irradiate the effluent and react with the peracetic acid solution. This application utilizes a bottom-in, top-out flow pattern to extend the water flow path, creating a plug-flow reaction environment that ensures sufficient contact and mixing between the effluent and the disinfectant. By combining the ultraviolet lamp assembly with the peracetic acid solution dosing, disinfection efficiency can be improved, the amount of disinfectant used can be reduced, and the generation of disinfection byproducts can be minimized, thus improving disinfection efficiency and effectiveness without increasing maintenance costs.

Description

Technical Field

[0001] This application relates to the field of wastewater treatment technology, specifically to a high-efficiency and low-risk disinfection device for wastewater treatment plant effluent. Background Technology

[0002] Currently, chlorine disinfection is the primary method used for effluent disinfection in wastewater treatment plants. However, residual chlorine-containing disinfectants in wastewater can further react with dissolved organic matter and other substances in the water, generating large amounts of toxic secondary disinfectant pollutants with carcinogenic risks (such as trihalomethanes and haloacetonitrs), posing significant threats to aquatic life and human health. Moreover, the structures of more than 50% of secondary total organochlorides have not yet been identified, and our understanding of their toxic effects is clearly insufficient.

[0003] In existing technologies, the control of secondary disinfection pollutants from chlorine disinfection mainly includes water treatment process optimization (such as the selection of new disinfectants such as chloramine and ozone) or subsequent advanced treatment (such as membrane treatment, activated carbon adsorption, advanced oxidation degradation, etc.). Although these processes have their own advantages, they also have certain application defects, such as susceptibility to interference from coexisting substances, high operation and maintenance costs, and secondary pollution. Utility Model Content

[0004] This application provides a high-efficiency and low-risk disinfection device for wastewater treatment plant effluent, which reduces secondary disinfection pollutants and secondary pollution without increasing maintenance costs.

[0005] According to this application, one embodiment provides a high-efficiency and low-risk disinfection device for wastewater treatment plant effluent, comprising:

[0006] A disinfection tank has an inlet and an outlet on its side wall, the outlet being positioned higher than the inlet, and the disinfection tank is used to store and disinfect wastewater.

[0007] A water circulation component is connected to the inlet and outlet and is used for the inlet and outlet of the effluent in the disinfection tank.

[0008] The dosing assembly includes a storage tank, a dosing pump, and a dosing pipe. The storage tank is used to store peracetic acid solution, the dosing pipe is used to connect the disinfection tank and the storage tank, and the dosing pump is used to provide power for the peracetic acid solution to enter the disinfection tank.

[0009] An ultraviolet lamp assembly is suspended inside the disinfection tank and is used to irradiate the effluent and react with the peracetic acid solution.

[0010] In another embodiment, the disinfection pool has an opening at the top, and the opening is covered with a cover plate to seal the disinfection pool.

[0011] In another embodiment, the water circulation assembly includes an inlet pipe, an outlet pipe, and a circulation pump. One end of the inlet pipe is connected to the inlet, and the other end is used to connect to the previous process and send tailwater in. One end of the outlet pipe is connected to the outlet, and the other end is used to connect to the next process. The circulation pump is installed on the inlet pipe and the outlet pipe.

[0012] In another embodiment, a vertical connecting pipe is provided inside the disinfection tank, with the lower end of the connecting pipe located near the bottom wall of the disinfection tank, and the connecting pipe is connected to the water outlet pipe to control the liquid level in the disinfection tank.

[0013] In another embodiment, the upper end of the connecting pipe is located near the cover plate, and the water outlet pipe is connected to the side wall of the connecting pipe.

[0014] In another embodiment, the cover plate is provided with a dosing port and an exhaust port. The dosing port is used to connect to the dosing pipe, and the exhaust port is connected to the exhaust gas treatment device through an exhaust pipe.

[0015] In another embodiment, a discharge port is provided at the bottom of the disinfection pool, and the discharge port is connected to a liquid level pipe parallel to the disinfection pool, so that the liquid level pipe and the disinfection pool form a communicating vessel.

[0016] In another embodiment, the ultraviolet lamp assembly includes a lifting bracket, a power supply box, and a plurality of lamp posts distributed on the lifting bracket. The cover plate is provided with a slot for the lamp posts to extend into. The lifting bracket is used to close the slot. The power supply box is disposed on the lifting bracket and is used to connect the power supply.

[0017] In another embodiment, a stirring assembly is also included, which is mounted on the cover plate and extends into the bottom of the disinfection tank.

[0018] In another embodiment, a control system is also included. Both the inlet and outlet are equipped with water quality detection devices. The water quality detection devices, stirring components, water circulation components, dosing components, and ultraviolet lamp components are all communicatively connected to the control system so that the control system can adjust the inlet flow rate, liquid level, and dosing parameters or actions according to the effluent water quality.

[0019] The wastewater treatment plant effluent high-efficiency and low-risk disinfection device according to the above embodiments forms a plug-flow reaction environment through water circulation at a low-level inlet and a high-level outlet. Structurally, this ensures full contact between the effluent and the disinfectant. By combining ultraviolet lamps with peracetic acid solution, disinfection efficiency can be improved, the amount of disinfectant used can be reduced, and the generation of disinfection byproducts such as trihalomethanes and haloacetonitrs can be decreased. The ultraviolet / peracetic acid disinfection combined technology has advantages such as economy, high efficiency, and no secondary pollution, improving disinfection efficiency and disinfection effect without increasing maintenance costs. Attached Figure Description

[0020] Figure 1 A schematic diagram of the overall structure of a high-efficiency and low-risk disinfection device for wastewater treatment plant effluent.

[0021] Figure 2 This is a top view of the overall structure of the disinfection device in one embodiment.

[0022] Possession Mark:

[0023] 1. Disinfection tank; 11. Inlet; 12. Outlet; 13. Discharge outlet; 14. Drain pipe; 15. Liquid level pipe;

[0024] 2. Cover plate; 21. Dosing port; 22. Vent hole;

[0025] 3. Water circulation components; 31. Inlet pipe; 32. Outlet pipe; 33. Circulation pump; 34. Connecting pipe;

[0026] 4. Dosing assembly; 41. Dosing tank; 42. Dosing pump; 43. Dosing hose;

[0027] 5. UV lamp assembly; 51. Lifting bracket; 52. Lamp post;

[0028] 6. Stirring assembly; 61. Drive motor; 62. Stirring paddle;

[0029] 7. Control system;

[0030] 8. Mounting bracket. Detailed Implementation

[0031] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments. Similar elements in different embodiments are referred to by related similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the present application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to the present application are not shown or described in the specification. This is to avoid obscuring the core parts of the present application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0032] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments, and the operational steps involved in each embodiment can also be rearranged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the specification and drawings are only for clearly describing a particular embodiment and do not imply that they represent the necessary components and / or order.

[0033] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0034] Wastewater treatment plant effluent disinfection primarily uses chlorine disinfection. However, residual chlorine disinfectants in wastewater can further react with dissolved organic matter and other substances in the water, generating large amounts of toxic secondary pollutants with carcinogenic risks. Current technologies for controlling these secondary pollutants mainly involve optimizing water treatment processes (such as using novel disinfectants like chloramines and ozone) or subsequent advanced treatments (such as membrane treatment, activated carbon adsorption, and advanced oxidative degradation). While these processes each have their advantages, they also have certain drawbacks, such as susceptibility to interference from coexisting substances, high operating and maintenance costs, and the potential for secondary pollution.

[0035] In recent years, peracetic acid (PAA) disinfectant has received widespread attention in the field of water treatment. Compared with traditional chlorine disinfectants, peracetic acid disinfectant has advantages such as high disinfection efficiency, convenient process operation, and low probability of secondary pollutant generation. However, the application of this technology in actual wastewater treatment plant effluent has not yet been carried out.

[0036] This application provides a high-efficiency and low-risk disinfection device for wastewater treatment plant effluent. It combines peracetic acid and ultraviolet lamps in a technical design and applies it to the field of wastewater treatment plant effluent disinfection, reducing secondary disinfection pollutants and secondary pollution without increasing maintenance costs.

[0037] Please refer to Figure 1 and Figure 2A high-efficiency and low-risk disinfection device for wastewater treatment plant effluent includes: a disinfection tank 1, with an inlet 11 and an outlet 12 on its side wall, the outlet 12 being positioned higher than the inlet 11, and the disinfection tank 1 being used to store and disinfect effluent; a water circulation assembly 3, connected to the inlet 11 and the outlet 12, and used for the inflow and outflow of effluent into the disinfection tank 1; a dosing assembly 4, including a storage tank 41, a dosing pump 42, and a dosing pipe 43, the storage tank 41 being used to store peracetic acid solution, the dosing pipe 43 being used to connect the disinfection tank 1 and the storage tank 41, and the dosing pump 42 being used to provide power for the peracetic acid solution to enter the disinfection tank 1; and an ultraviolet lamp assembly 5, suspended inside the disinfection tank 1, used to irradiate the effluent and react with the peracetic acid solution.

[0038] UV / peracetic acid disinfection technology boasts advantages such as strong oxidizing power, synergistic effects of multiple factors, and no secondary pollution. Its disinfection efficiency in inactivating intestinal microorganisms is higher than that of UV light, hydrogen peroxide, and traditional chlorine disinfection. When applied to wastewater treatment plant effluent, it can significantly reduce the amount of disinfectant used and decrease the generation of disinfection byproducts such as trihalomethanes and haloacetonits. Peracetic acid disinfectant generates a large number of highly oxidizing free radicals through catalytic decomposition, significantly improving the efficiency of wastewater sterilization and the degradation of organic pollutants. The combined UV / peracetic acid disinfection technology offers advantages such as economy, high efficiency, and no secondary pollution.

[0039] This embodiment uses water circulation through a low-level inlet 11 and a high-level outlet 12 to create a plug-flow reaction environment, structurally ensuring sufficient contact between the effluent and the disinfectant. By combining the ultraviolet lamp assembly with peracetic acid solution, disinfection efficiency can be improved, the amount of disinfectant used can be reduced, and the generation of disinfection byproducts such as trihalomethanes and haloacetonitrs can be decreased. The ultraviolet / peracetic acid disinfection combined technology has advantages such as economy, high efficiency, and no secondary pollution, improving disinfection efficiency and disinfection effect without increasing maintenance costs.

[0040] For details, please refer to Figure 1 and Figure 2 The disinfection pool 1 is designed as a container with an open top. It can be rectangular, cylindrical, or other shapes and is made of UPVC material. The opening at the top of the disinfection pool 1 is covered by a cover plate 2 to seal the disinfection pool 1.

[0041] Please refer to Figure 1 and Figure 2 The height difference design of disinfection tank 1 forms a bottom-in, top-out flow pattern, which extends the water flow path and ensures that the effluent and disinfectant are fully in contact and mixed. Discharge port 13 is set at the bottom of disinfection tank 1. Discharge port 13 is equipped with an empty valve and an empty pipe 14 for timed emptying, so as to achieve zero sludge deposition and avoid affecting the transparency of the water body, thereby affecting the penetration performance of the ultraviolet lamp and interfering with the disinfection efficiency.

[0042] In other embodiments, the discharge port 13 is connected to a liquid level pipe 15 parallel to the disinfection pool 1, so that the liquid level pipe 15 and the disinfection pool 1 form a communicating vessel. The liquid level pipe 15 is made of transparent glass so that the liquid level height of the disinfection pool 1 can be observed intuitively from the outside.

[0043] For further details, please refer to... Figure 1 and Figure 2 The water circulation component 3 includes an inlet pipe 31, an outlet pipe 32, and a circulation pump 33. One end of the inlet pipe 31 is connected to the inlet 11, and the other end is used to connect to the previous process and send the tailwater in. One end of the outlet pipe 32 is connected to the outlet 12, and the other end is used to connect to the next process. The circulation pump 33 is installed on the inlet pipe 31 and the outlet pipe 32. In this embodiment, the connection between the pipes is a flange connection. The inlet pipe 31 connects the outlet of the secondary sedimentation tank of the sewage treatment plant and the disinfection tank 1, and the outlet pipe 32 connects the disinfection tank 1 and the clear water tank.

[0044] Furthermore, the circulation pump 33 can be a corrosion-resistant peristaltic pump, which is installed at the corresponding positions of the inlet pipe 31 and the outlet pipe 32. The flow rate can be controlled by controlling the peristaltic pump. The circulation pump 33 forces the water flow to form an internal circulation vortex, which, together with the high-level outlet 12, eliminates short-circuiting and ensures the uniformity of the reaction throughout the pool.

[0045] Furthermore, water quality testing devices are installed at both the inlet 11 and the outlet 12. The effect of effluent disinfection can be intuitively understood based on the water quality monitoring data, which facilitates the adjustment of the hydraulic retention time (HRT) to ensure sufficient reaction time until qualified water quality is achieved.

[0046] For further details, please refer to... Figure 1 and Figure 2 The disinfection tank 1 is equipped with a vertical connecting pipe 34. The lower end of the connecting pipe 34 is located near the bottom wall of the disinfection tank 1 and is connected to the outlet pipe 32 to control the liquid level in the disinfection tank 1. The upper end of the connecting pipe 34 is located near the cover plate 2. The outlet pipe 32 is connected to the side wall of the connecting pipe 34. Specifically, the outlet pipe 32 is horizontally welded to the side wall of the connecting pipe 34. The lower end of the connecting pipe 34 can extend into the bottom of the tank, which facilitates water discharge at various liquid levels and achieves continuous water intake and discharge.

[0047] For further details, please refer to... Figure 1 and Figure 2 The cover plate 2 has a dosing port 21 and an exhaust port 22. The dosing port 21 is used to connect to the dosing pipe 43, and the exhaust port 22 is connected to the exhaust gas treatment device through the exhaust pipe. In this embodiment, all pipe holes are installed with flange connections.

[0048] Specifically, the dosing pipe 43 is vertically inserted into the dosing port 21 of the cover plate 2 and locked through the flange. The lower end of the dosing pipe 43 can extend into the liquid surface to avoid solution splashing and facilitate solution contact and mixing for disinfection at the lower inlet 11. The vent 22 can discharge irritating gases, and an activated carbon filter can be installed at the end of the vent pipe to reduce irritating gas pollution.

[0049] For further details, please refer to... Figure 1 and Figure 2 The ultraviolet lamp assembly 5 includes a lifting bracket 51, a power supply box, and several lamp posts 52 distributed on the lifting bracket 51. The cover plate 2 is provided with a slot for the lamp posts 52 to extend into. The lifting bracket 51 is used to close the slot. The power supply box is set on the lifting bracket 51 and is used to connect the power supply.

[0050] Specifically, in other embodiments, the cover plate 2 can be provided with a door for closing and opening the slot, and the door is equipped with a handle. The lifting bracket 51 can also be fixed above the liquid surface inside the disinfection pool 1 by bolts. The ultraviolet lamp assembly 5 can be seen by opening the slot with the handle, and can be replaced or other operations can be performed.

[0051] Please refer to Figure 1 and Figure 2 The lamp post 52 can be made of three sets. The inside of the lamp post 52 is a UV lamp body, and the outside is a light-transmitting protective lamp tube to isolate the water body. The power box is fixed on the upper end of the lifting bracket 51. The connection part between the wire and the lamp post 52 is above the liquid surface, so it is not easy to be corroded. The power box is set away from the liquid to improve the safety of use. The UV lamp assembly 5 can be lifted out as a whole through the lifting bracket 51 for easy replacement.

[0052] In other embodiments, the lifting bracket 51 can be designed as a semi-automatic structure with a rocker arm and screw, or an automatic drive structure such as a motor / cylinder, to reduce manual operation, improve safety, and make the lifting and lowering of the ultraviolet lamp assembly 5 more stable.

[0053] For further details, please refer to... Figure 1 and Figure 2 A stirring assembly 6 is installed on the cover plate 2 and extends into the bottom of the disinfection tank 1. Specifically, the stirring assembly 6 includes a drive motor 61 and a stirring paddle. The drive motor 61 is installed on the cover plate 2; one end of the stirring paddle is connected to the output end of the drive motor 61, and the other end of the paddle extends into the interior of the disinfection tank 1. The paddle can be positioned directly below the ultraviolet lamp. By stirring, radial flow shearing free radical clusters are generated, which enhances the collision and mixing of the peracetic acid solution and the wastewater, thereby improving the disinfection efficiency.

[0054] Furthermore, a stirring frame with a welded stroke via angle steel is provided on the cover plate 2. The stirring frame is bolted to the cover plate 2, and the base of the drive motor 61 is bolted to the stirring frame, thereby improving the stability of the stirring assembly 6.

[0055] In this embodiment, sealing structures, such as sealing rings or other locking structures, are provided at the locations that need to be sealed, such as between the cover plate 2 and the disinfection pool 1, and between the lifting bracket 51 and the cover plate 2. For example, a locking buckle structure is provided between the cover plate 2 and the edge of the disinfection pool 1. The specific locations can be designed and optimized according to the sealing location and structural requirements.

[0056] In this embodiment, please refer to Figure 1 and Figure 2 The disinfection device is designed with a special mounting frame 8, which is fixed by welding square steel. The disinfection pool 1 is fixed to the upper end of the mounting frame 8, and the dosing component 4 is set below the disinfection pool 1 on the mounting frame 8 and connected by a pipe. The pipe can be arranged and fixed along the frame of the mounting frame 8.

[0057] The disinfection device is used in wastewater treatment plant effluent and needs to be tested. In this embodiment, the test scale is 5 m3 / d. The ultraviolet / peracetic acid disinfection tank 1 is made of UPVC material with an effective volume of 35L. The hydraulic retention time (HRT) is controlled by the liquid level and is 10 min. The ultraviolet lamp assembly 5 has 3 lamp columns 52, each with a length of 550 mm, a tube diameter of 23 mm, an ultraviolet intensity of 85 μW / cm2, a power of 40 W, and a wavelength of 254 nm. The peracetic acid dosage is controlled to be 2~5 mg / L and the contact time is 10 min by adjusting the dosing pump 42. The water quality of the influent and effluent of the device is monitored regularly.

[0058] In the aforementioned large-scale tests, no fecal coliforms were found in the effluent from the UV / peracetic acid disinfection tank 1. Compared to chlorine disinfectants, this device can achieve good disinfection results under low concentration and low hydraulic retention time conditions. The effluent concentrations of disinfection byproducts trihalomethanes, haloacetonitrs, haloketones, and chloride hydrates were 1.97 μg / L, 0.58 μg / L, 0.77 μg / L, and 0.56 μg / L, respectively. The total concentration of disinfection byproducts generated was reduced by 92.8% compared to that generated by chlorine disinfectants, greatly reducing the risk of pollution from disinfection byproducts.

[0059] In this embodiment, all components of the disinfection device are controlled and regulated as a whole by the control system 7. The water quality detection device, stirring component 6, water circulation component 3, dosing component 4, and ultraviolet lamp component 5 are all communicatively connected to the control system 7. The water quality detection device can be equipped with an online COD meter at the inlet 11 and other residual detection and analysis equipment such as a residual chlorine analyzer at the outlet 12. The control system 7 receives inlet and outlet flow rates and water quality data through a PLC controller and dynamically adjusts the corresponding actions such as the frequency of the dosing pump 42 and the speed of the circulation pump 33. In this embodiment, the control system 7 and the corresponding operating hardware are integrated on one side of the disinfection tank 1.

[0060] The above-described specific examples are for illustrative purposes only and are not intended to limit the scope of this invention. Those skilled in the art to which this invention pertains can make various simple deductions, modifications, or substitutions based on the concept of this invention.

Claims

1. A device for efficient and low risk disinfection of effluent water from a sewage treatment plant, characterized in that, include: The disinfection tank (1) has an inlet (11) and an outlet (12) on its side wall. The outlet (12) is set higher than the inlet (11), and the disinfection tank (1) is used to store and disinfect the wastewater. The water circulation component (3) is connected to the inlet (11) and outlet (12) and is used for the inlet and outlet of the tailwater in the disinfection tank (1); The dosing assembly (4) includes a storage tank (41), a dosing pump (42), and a dosing pipe (43). The storage tank (41) is used to store peracetic acid solution, the dosing pipe (43) is used to connect the disinfection tank (1) and the storage tank (41), and the dosing pump (42) is used to provide power for the peracetic acid solution to enter the disinfection tank (1). The ultraviolet lamp assembly (5) is suspended in the disinfection tank (1) and is used to irradiate the tailwater and react with the peracetic acid solution.

2. The sanitizing device of claim 1, wherein, The disinfection pool (1) has an opening at the top, and the opening of the disinfection pool (1) is covered by a cover plate (2) to seal the disinfection pool (1).

3. The sanitizing device of claim 2, wherein, The water circulation component (3) includes an inlet pipe (31), an outlet pipe (32), and a circulation pump (33). One end of the inlet pipe (31) is connected to the inlet (11), and the other end is used to connect to the previous process and send tailwater. One end of the outlet pipe (32) is connected to the outlet (12), and the other end is used to connect to the next process. The circulation pump (33) is installed on the inlet pipe (31) and the outlet pipe (32).

4. The sanitizing device of claim 3, wherein, The disinfection tank (1) is equipped with a vertical connecting pipe (34). The lower end of the connecting pipe (34) is located close to the bottom wall of the disinfection tank (1), and the connecting pipe (34) is connected to the water outlet pipe (32) to control the liquid level of the disinfection tank (1).

5. The sanitizing device of claim 4, wherein, The upper end of the connecting pipe (34) is located near the cover plate (2), and the water outlet pipe (32) is connected to the side wall of the connecting pipe (34).

6. The sanitizing device of claim 2, wherein, The cover plate (2) is provided with a dosing port (21) and an air outlet (22). The dosing port (21) is used to connect to the dosing pipe (43), and the air outlet (22) is connected to the exhaust gas treatment device through the exhaust pipe.

7. The sanitizing device of claim 6, wherein, The bottom of the disinfection pool (1) is provided with a discharge port (13), and the discharge port (13) is connected to a liquid level pipe (15) parallel to the disinfection pool (1) so that the liquid level pipe (15) and the disinfection pool (1) form a communicating vessel.

8. The sanitizing device of claim 2, wherein, The ultraviolet lamp assembly (5) includes a lifting bracket (51), a power supply box, and a number of lamp posts (52) distributed on the lifting bracket (51). The cover plate (2) is provided with a slot for the lamp posts (52) to extend into. The lifting bracket (51) is used to close the slot. The power supply box is provided on the lifting bracket (51) and is used to connect the power supply.

9. The sterilization apparatus of any one of claims 2-8, wherein, It also includes a stirring assembly (6), which is installed on the cover plate (2) and extends into the bottom of the disinfection pool (1).

10. The sanitizing device of claim 9, wherein, It also includes a control system (7), and the inlet (11) and outlet (12) are equipped with water quality detection devices. The water quality detection devices, stirring components (6), water circulation components (3), dosing components (4) and ultraviolet lamp components (5) are all connected to the control system (7) so that the control system (7) can adjust the inlet flow rate, liquid level and dosing parameters or actions according to the effluent water quality.

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