Underground sewage treatment plant composite sedimentation tank structure

Abstract

This utility model discloses a composite sedimentation tank structure for an underground wastewater treatment plant, comprising a coagulation tank, a flocculation tank, and an inclined plate sedimentation tank arranged sequentially within the underground wastewater treatment plant. The bottom of the coagulation tank is connected to the flocculation tank via a flow channel, and the flocculation tank and the inclined plate sedimentation tank are connected via a flow channel. A slow-speed agitator is installed at the top of the flocculation tank, and an overflow steel trough is installed on one side of the top of the inclined plate sedimentation tank. A circulation pump is installed at the bottom of the inclined plate sedimentation tank. This utility model relates to the field of wastewater treatment technology. A layer control mechanism is installed at the top of the coagulation tank, and a mechanical stirring component is installed on the moving end of the layer control mechanism. The movable mechanical stirring structure assists coagulation, replacing the traditional fixed-position stirring coagulation. Due to the multi-layer mechanical stirring, the coagulant and wastewater are mixed faster and more thoroughly, which not only enhances the coagulation effect but also saves on reagents.

Description

Technical Field

[0001] This utility model relates to the field of wastewater treatment technology, specifically to the structure of a composite sedimentation tank in an underground wastewater treatment plant. Background Technology

[0002] As urban infrastructure, wastewater treatment plants are a standard feature of modern society. However, traditional wastewater treatment plants are mostly built above ground, occupying large areas, having a significant environmental impact, and often facing the challenge of the "NIMBY (Not In My Backyard) effect." By burying water treatment systems underground and constructing parks, parking lots, stadiums, and other facilities above ground, the NIMBY effect gradually weakens and disappears while saving land. Due to space constraints and environmental requirements, underground wastewater treatment plants typically prioritize intensive, efficient, and space-saving sedimentation tanks. High-efficiency sedimentation tanks (coagulation sedimentation tanks) enhance flocculation by adding coagulants, significantly improving sedimentation efficiency. Their treatment capacity per unit area is 3-5 times that of traditional sedimentation tanks, making them suitable for the limited space of underground enclosures and widely used in underground wastewater treatment plants. In the process of adding coagulants, existing high-efficiency sedimentation tanks usually use mechanical stirring mechanisms to agitate the sewage and coagulants to improve the mixing efficiency of coagulants and sewage. However, the traditional fixed-position stirring mechanism has a relatively simple structure, the mixture is prone to stratification, and the mixing uniformity is poor, which is not conducive to the efficient treatment of sewage. In view of this, in-depth research was conducted on the above problems, which led to the development of this case. Utility Model Content

[0003] To address the shortcomings of existing technologies, this utility model provides a composite sedimentation tank structure for underground sewage treatment plants, solving the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a composite sedimentation tank structure for an underground wastewater treatment plant, comprising a coagulation tank, a flocculation tank, and an inclined plate sedimentation tank arranged sequentially within the underground wastewater treatment plant. The bottom of the coagulation tank is connected to the flocculation tank via a flow channel, and the flocculation tank and the inclined plate sedimentation tank are connected via a flow passage. A slow-speed agitator is installed at the top of the flocculation tank. An overflow steel trough is installed on one side of the top of the inclined plate sedimentation tank. A circulation pump is installed at the bottom of the inclined plate sedimentation tank, and the outlet end of the circulation pump is connected to the flow channel. The lower end of the inclined plate sedimentation tank is connected to a sludge treatment system. A flocculant dosing mechanism is installed at the top of the flocculation tank, and a layer control mechanism is installed on one side of the flocculant dosing mechanism. A mechanical stirring component is installed at the moving end of the layer control mechanism. The layer control mechanism includes a fixed frame, a vertical control component, a guide support component, and a movable seat. The fixed frame is installed at the top of the coagulation tank, the vertical control component is installed inside the fixed frame, the guide support component is symmetrically arranged on both sides of the fixed frame, and the movable seat is installed on the movable end of the vertical adjustment component and connected to the guide support component.

[0005] The aforementioned vertical control component includes a fixed slot, a transmission screw, a screw nut, and a servo drive. The fixed slot is vertically arranged within a fixed frame. The transmission screw is rotatably arranged within the fixed slot. The screw nut is embedded in a movable seat and threadedly engaged with the transmission screw. The output end of the servo drive is connected to the exposed end of the transmission screw.

[0006] The aforementioned servo drive includes a servo motor, a reducer, and an output shaft. The input end of the reducer is connected to the drive end of the servo motor, and one end of the output shaft is connected to the output end of the reducer, while the other end is connected to the transmission lead screw.

[0007] The aforementioned guide support assembly includes a guide rail and a slider. The guide rail is symmetrically arranged on the side wall of the fixed frame, and the slider is slidably fitted on the guide rail and fixedly connected to the movable seat.

[0008] The aforementioned mechanical mixing assembly includes a limiting support sleeve, a mixing shaft, a mixing paddle, a rotary motor, and a reducer. The limiting support sleeve is mounted on a movable seat. The mixing shaft is rotatably inserted into the limiting support sleeve with its lower end extending into the coagulation tank. The mixing paddle is fixedly mounted on the lower end of the mixing shaft. The input end of the reducer is connected to the drive end of the rotary motor, and the output end of the reducer is connected to the upper end of the mixing shaft.

[0009] The aforementioned flocculant dosing mechanism includes a coagulant storage tank, a dosing pump, and an annular injection pipe. The inlet end of the dosing pump is connected to the lower end of the coagulant storage tank. The annular injection pipe is located at the top of the coagulation tank and is coaxially arranged with the mechanical stirring assembly. The lower end of the annular injection pipe has a nozzle along the annular array. The outlet end of the dosing pump is connected to the annular injection pipe through a connecting pipe. Beneficial effects

[0010] This utility model provides a composite sedimentation tank structure for underground sewage treatment plants. The underground wastewater treatment plant's composite sedimentation tank structure features a layer control mechanism at the top of the coagulation tank. A mechanical stirring component is mounted on the movable end of this mechanism, assisting coagulation and replacing traditional fixed-position stirring. This multi-layered mechanical stirring allows for faster and more thorough mixing of the coagulant and wastewater, enhancing the coagulation effect and saving on chemicals. The coagulant is added to the raw water and rapidly mixes with suspended solids under the action of the mechanical stirring component. By neutralizing the negative charge on the particle surface, the particles are destabilized, forming small flocs that then enter the flocculation tank. In the flocculation tank, flocculant is added and a slow-speed stirrer is used to agitate the water, ensuring thorough mixing of the chemicals and flocs without damaging the already formed large flocs. The effluent after flocculation enters the bottom of the inclined plate of the sedimentation tank and flows upwards to the upper collection area. Particles and flocs settle on the surface of the inclined plate and slide down under gravity. The settled water is collected and discharged by stainless steel collection troughs distributed at the top of the inclined plate sedimentation tank. Attached Figure Description

[0011] Figure 1 This is a front view schematic diagram of the composite sedimentation tank structure of the underground sewage treatment plant described in this utility model.

[0012] Figure 2 This utility model Figure 1 A partially enlarged structural diagram.

[0013] Figure 3 This is an isometric structural diagram of the layer control mechanism described in this utility model.

[0014] In the diagram: 1. Coagulation tank; 2. Flocculation tank; 3. Inclined plate sedimentation tank; 4. Slow-speed agitator; 5. Guide channel; 6. Flow channel; 7. Overflow steel trough; 8. Circulation pump; 9. Sludge treatment system; 10. Fixed frame; 11. Moving seat; 12. Fixed groove; 13. Transmission screw; 14. Screw nut; 15. Servo motor; 16. Reducer; 17. Output shaft; 18. Guide rail; 19. Slider; 20. Limit support sleeve; 21. Agitator shaft; 22. Agitator paddle; 23. Rotary motor; 24. Reducer; 25. Coagulant storage tank; 26. Dosing pump; 27. Annular injection pipe. Detailed Implementation

[0015] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0016] Example: Refer to the appendix of the instruction manual Figure 1-3 As can be seen, this application specifically designs a composite sedimentation tank structure for an underground wastewater treatment plant, including a coagulation tank 1, a flocculation tank 2, and an inclined plate sedimentation tank 3 arranged sequentially within the underground wastewater treatment plant. The bottom of the coagulation tank 1 is connected to the flocculation tank 2 via a guide channel 5, and the flocculation tank 2 and the inclined plate sedimentation tank 3 are connected via a flow channel 6. A slow-speed agitator 4 is installed at the top of the flocculation tank 2, an overflow steel trough 7 is installed on one side of the top of the inclined plate sedimentation tank 3, a circulation pump 8 is installed at the bottom of the inclined plate sedimentation tank 3, the outlet end of the circulation pump 8 is connected to the guide channel 5, and the lower end of the inclined plate sedimentation tank 3 is connected to the sludge treatment system 9. A flocculant dosing mechanism is installed at the top of the flocculation tank 2, and a layer control mechanism is installed on one side of the flocculant dosing mechanism. A mechanical stirring component is installed at the moving end of the layer control mechanism. The layer control mechanism includes a fixed frame 10, a vertical control component, a guide support component, and a moving base 11. The fixed frame 10 is installed at the top of the coagulation tank 1, and the vertical control component is installed on the fixed frame 10. Within the 0, guide support components are symmetrically arranged on both sides of the fixed frame 10. The movable seat 11 is located on the movable end of the vertical adjustment component and connected to the guide support components. A layer control mechanism is set at the top of the coagulation tank 1. A mechanical stirring component is set on the movable end of the layer control mechanism. The movable mechanical stirring structure assists coagulation, replacing the traditional fixed-position stirring coagulation. Due to the multi-layer mechanical stirring, the coagulant and sewage are mixed faster and more thoroughly, which not only enhances the coagulation effect but also saves on chemicals. The coagulant is added to the raw water and, under the action of the mechanical stirring component, quickly mixes with the suspended solids in the sewage. By neutralizing the negative charge on the particle surface, the particles are "destabilized" and form small flocs, which then enter the flocculation tank 2. Flocculant is added to the flocculation tank 2 and stirred with a slow stirrer 4. This ensures that the chemicals and flocs are fully mixed without destroying the large flocs that have already formed. After flocculation, the effluent enters the bottom of the inclined plate of the sedimentation tank and then flows upward to the upper collection area. Particles and flocs settle on the surface of the inclined plate and slide down under gravity. The settled water is collected and discharged by the stainless steel water collection tank distributed at the top of the inclined plate sedimentation tank 3.

[0017] In specific implementation, the aforementioned vertical control component includes a fixed groove 12, a transmission screw 13, a screw nut 14, and a servo drive. The fixed groove 12 is vertically arranged within the fixed frame 10. The transmission screw 13 is rotatably arranged within the fixed groove 12. The screw nut 14 is embedded in the movable seat 11 and threadedly engaged with the transmission screw 13. The output end of the servo drive is connected to the exposed end of the transmission screw 13. The servo drive includes a servo motor 15, a reducer 16, and an output shaft 17. The input end of the reducer 16 is connected to the drive end of the servo motor 15. One end of the output shaft 17 is connected to the output end of the reducer 16, and the other end is connected to the transmission screw 13. The aforementioned guide support component includes a guide rail 18 and a slider 19. The guide rail 18 is symmetrically arranged on the side wall of the fixed frame 10. The slider 19 is slidably fitted onto the guide rail 18 and fixedly connected to the movable seat 11. The aforementioned mechanical stirring assembly includes a limiting support sleeve 20, a stirring shaft 21, a stirring paddle 22, a rotary motor 23, and a reducer 24. The limiting support sleeve 20 is mounted on the movable seat 11. The stirring shaft 21 is rotatably inserted into the limiting support sleeve 20, with its lower end extending into the coagulation tank 1. The stirring paddle 22 is fixedly mounted on the lower end of the stirring shaft 21. The input end of the reducer 24 is connected to the drive end of the rotary motor 23, and the output end of the reducer 24 is connected to the upper end of the stirring shaft 21. The flocculant dosing mechanism includes a coagulant storage tank, a drug delivery pump 26, and an annular injection pipe 27. The inlet end of the drug delivery pump 26 is connected to the lower end of the coagulant storage tank. The annular injection pipe 27 is located at the top of the coagulation tank 1 and is coaxially arranged with the mechanical stirring assembly. The lower end of the annular injection pipe 27 has a nozzle along the annular array. The discharge end of the drug delivery pump 26 is connected to the annular injection pipe 27 through a connecting pipe.

[0018] The specific workflow is as follows: Coagulant from the coagulant storage tank is drawn out by the dosing pump 26 and evenly added to the raw water in the coagulation tank 1 through the annular injection pipe 27. During the dosing process, the rotary motor 23 is started, driving the reducer 24 to control the rotation of the stirring shaft 21. Simultaneously, the servo motor 15 is started, and through the cooperation of the servo motor 15 and the reducer 16, the transmission screw 13 rotates, which in turn drives the moving seat 11 to move vertically, achieving multi-level mixing. Under the rotation of the stirring shaft 21 and the stirring paddle 22, the coagulant rapidly mixes with the suspended solids in the wastewater. By neutralizing the negative charge on the particle surface, the particles are destabilized, forming small flocs that then enter the flocculation tank 2. Simultaneously, phosphorus in the raw water reacts with the coagulant to form phosphates, achieving chemical phosphorus removal. The returned sludge and the small flocs formed by coagulation are rapidly mixed by the mechanical stirring components, forming denser and heavier flocs with the sludge as the core, which facilitates rapid sedimentation in the sedimentation tank. Flocculant is added to flocculation tank 2. The flocculant promotes the formation of larger flocs from the small flocs through adsorption, charge neutralization, and mutual bridging. The slow-speed stirrer 4 ensures that the agent and flocs are fully mixed without damaging the already formed large flocs. After flocculation, the effluent enters the bottom of the inclined plate of the sedimentation tank and then flows upward to the upper water collection area. Particles and flocs settle on the surface of the inclined plate and slide down under gravity. The high upward flow velocity and the 60° inclination of the inclined plate can form a continuous self-scraping process, preventing flocs from accumulating on the inclined plate. The sludge slides down the surface of the inclined plate and settles at the bottom of the sedimentation tank. Then, the circulating pump 8 transports part of the sludge to the coagulation and flocculation tank 2, and the remaining sludge flows to the sludge treatment system 9 by gravity. The settled water is collected and discharged by the stainless steel water collection tank distributed at the top of the inclined plate sedimentation tank 3.

[0019] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, the phrase "comprising an element defined as..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0020] Although 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 alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A composite sedimentation tank structure for an underground wastewater treatment plant, comprising a coagulation tank, a flocculation tank, and an inclined plate sedimentation tank arranged sequentially within the underground wastewater treatment plant, characterized in that... The bottom of the coagulation tank is connected to the flocculation tank via a flow channel. The flocculation tank and the inclined plate sedimentation tank are connected via a flow channel. A slow agitator is installed at the top of the flocculation tank. An overflow steel trough is installed on one side of the top of the inclined plate sedimentation tank. A circulation pump is installed at the bottom of the inclined plate sedimentation tank. The outlet end of the circulation pump is connected to the flow channel. The lower end of the inclined plate sedimentation tank is connected to the sludge treatment system. A flocculant dosing mechanism is installed at the top of the flocculation tank. A layer control mechanism is installed on one side of the flocculant dosing mechanism. A mechanical stirring component is installed at the moving end of the layer control mechanism. The layer control mechanism includes a fixed frame, a vertical control component, a guide support component, and a movable seat. The fixed frame is installed at the top of the coagulation tank, the vertical control component is installed inside the fixed frame, the guide support component is symmetrically arranged on both sides of the fixed frame, and the movable seat is installed on the movable end of the vertical adjustment component and connected to the guide support component.

2. The composite sedimentation tank structure for underground wastewater treatment plants according to claim 1, characterized in that, The vertical control component includes a fixed slot, a transmission screw, a screw nut, and a servo drive. The fixed slot is vertically arranged in a fixed frame. The transmission screw is rotatably arranged in the fixed slot. The screw nut is embedded in a movable seat and threadedly engaged with the transmission screw. The output end of the servo drive is connected to the exposed end of the transmission screw.

3. The composite sedimentation tank structure for underground sewage treatment plants according to claim 2, characterized in that, The servo drive includes a servo motor, a reducer, and an output shaft. The input end of the reducer is connected to the drive end of the servo motor, and one end of the output shaft is connected to the output end of the reducer, while the other end is connected to the transmission screw.

4. The composite sedimentation tank structure for underground sewage treatment plants according to claim 1, characterized in that, The guide support assembly includes a guide rail and a slider. The guide rail is symmetrically arranged on the side wall of the fixed frame, and the slider is slidably fitted on the guide rail and fixedly connected to the movable seat.

5. The composite sedimentation tank structure for underground sewage treatment plants according to claim 1, characterized in that, The mechanical stirring assembly includes a limiting support sleeve, a stirring shaft, a stirring paddle, a rotary motor, and a reducer. The limiting support sleeve is mounted on a movable seat. The stirring shaft is rotatably inserted into the limiting support sleeve with its lower end extending into the coagulation tank. The stirring paddle is fixedly mounted on the lower end of the stirring shaft. The input end of the reducer is connected to the drive end of the rotary motor, and the output end of the reducer is connected to the upper end of the stirring shaft.

6. The composite sedimentation tank structure for underground sewage treatment plants according to claim 1, characterized in that, The flocculant dosing mechanism includes a coagulant storage tank, a dosing pump, and an annular injection pipe. The inlet end of the dosing pump is connected to the lower end of the coagulant storage tank. The annular injection pipe is located at the top of the coagulation tank and is coaxially arranged with the mechanical stirring assembly. The lower end of the annular injection pipe has a nozzle along the annular array. The outlet end of the dosing pump is connected to the annular injection pipe through a connecting pipe.

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