Efficient nitrogen removal system based on multistage AO series synergistic autotrophic denitrification
By using a multi-stage AO series synergistic autotrophic denitrification system, which combines anaerobic, heterotrophic and autotrophic denitrification zones, and utilizes autotrophic denitrification packing to provide electron donors, the system solves the problem of poor nitrogen removal efficiency in wastewater treatment plants due to insufficient carbon sources and low-temperature environments, thus achieving efficient and energy-saving nitrogen removal.
Patent Information
- Application Number
- CN202422204499.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-09
- Publication Date
- 2025-11-21
- Estimated Expiration
- 2034-09-09
AI Technical Summary
Existing wastewater treatment plants suffer from high operating costs due to insufficient carbon sources, and the autotrophic denitrification process is affected by the biological activity in low-temperature environments, making it difficult to achieve efficient nitrogen removal.
A multi-stage AO series synergistic autotrophic denitrification system is adopted, which combines anaerobic, heterotrophic and autotrophic denitrification zones. The autotrophic denitrification packing provides electron donors, reducing the addition of carbon sources. Combined with a hydraulic mixing and stirring system and an interception net, it ensures that the packing is not lost.
It improves nitrogen removal efficiency, reduces operating costs, solves the problem of poor denitrification effect in low-temperature environments, has a simple structure that saves investment, and is suitable for new or renovated wastewater treatment plants.
Smart Images
Figure CN223576255U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the field of sewage treatment, more particularly to a kind of based on multistage AO series cooperation autotrophic denitrification high-efficiency nitrogen removal system. BACKGROUND
[0002] In existing urban or industrial sewage treatment plant, the problem of serious shortage of carbon source exists in influent, in order to improve the effect of denitrification, a large amount of carbon source as electron donor needs to be added. This leads to high operating cost and complex management problems. Of course, there are also many denitrification using autotrophic denitrification process, this process is generally used in advanced treatment stage as deep denitrification, but after secondary treatment, the water temperature of sewage is reduced obviously, especially in winter, which will affect the biological activity of autotrophic denitrification filter. In addition, the corresponding discharge standard of municipal sewage treatment plant has been introduced in various places, and the index of nitrogen has also been improved accordingly, which requires to explore more efficient and energy-saving technical route to realize stable discharge and achieve the goal of energy saving and low carbon. SUMMARY
[0003] The utility model aims at providing a kind of based on multistage AO series cooperation autotrophic denitrification high-efficiency nitrogen removal system, can more efficiently, more energy-savingly improve the effect of denitrification, reduce operating cost.
[0004] The technical scheme of the utility model is: a kind of based on multistage AO series cooperation autotrophic denitrification high-efficiency nitrogen removal system, first AO unit, multistage second AO unit and third AO unit are sequentially connected in biological pool;First AO unit is composed of anaerobic zone and first aerobic zone, anaerobic zone is equipped with anaerobic water distribution port;Second AO unit is composed of heterotrophic denitrification anoxic zone and second aerobic zone, heterotrophic denitrification anoxic zone is equipped with heterotrophic water distribution port;Third AO unit is composed of autotrophic denitrification anoxic zone and third aerobic zone.
[0005] As a further improvement of the utility model, autotrophic denitrification anoxic zone is equipped with autotrophic water distribution port.
[0006] As a further improvement of the utility model, a plurality of fixed cages are fixedly arranged in autotrophic denitrification anoxic zone, and autotrophic denitrification filler is filled in fixed cage.
[0007] As a further improvement of the utility model, interception net is respectively arranged at the water pass port between second aerobic zone of last stage second AO unit and autotrophic denitrification anoxic zone and the water pass port between autotrophic denitrification anoxic zone and third aerobic zone.
[0008] As a further improvement of the utility model, hydraulic mixing and stirring system is arranged in anaerobic zone, heterotrophic denitrification anoxic zone and autotrophic denitrification anoxic zone.
[0009] As a further improvement of the present application, the anaerobic zone is provided with a sludge backflow port, and the sludge backflow port is connected to the secondary sedimentation tank through a backflow sludge channel.
[0010] The present application has the following advantages:
[0011] 1. The present application combines multi-stage AO with autotrophic denitrification to provide denitrification effect, reduce carbon source dosage, and reduce operation cost.
[0012] 2. The present application sets the autotrophic denitrification filler in the biological tank to solve the problem of poor denitrification effect caused by low temperature in the advanced treatment section.
[0013] 3. The present application has simple structure, saves investment, reduces construction cost, and is more low-carbon and environmentally friendly in operation, and can be applied to the newly built or reconstructed biological tank of a sewage treatment plant. BRIEF DESCRIPTION OF DRAWINGS
[0014] Figure 1 is a schematic view of the planar structure of the present application.
[0015] Figure 2 is Figure 1 A-A view in the
[0016] In the figure: 1-biological tank; 2-anaerobic water distribution port; 3-sludge backflow port; 4-backflow sludge channel; 5-anaerobic zone; 6-first aerobic zone; 7-heterotrophic denitrification anoxic zone; 8-autotrophic denitrification anoxic zone; 9-interception net; 10-fixed cage; 11-hydraulic mixing and stirring system; 13-second aerobic zone; 14-heterotrophic water distribution port; 15-third aerobic zone; 16-autotrophic water distribution port. DETAILED DESCRIPTION
[0017] The present application will be described in detail below with reference to the accompanying drawings.
[0018] As shown in Figure 1 , Figure 2 , a multi-stage AO series-based autotrophic denitrification high-efficiency denitrification system is provided in a biological tank 1, which is provided with a first AO unit, a multi-stage second AO unit and a third AO unit connected in series; the first AO unit is composed of an anaerobic zone 5 and a first aerobic zone 6, and the anaerobic zone 5 is provided with an anaerobic water distribution port 2; the second AO unit is composed of a heterotrophic denitrification anoxic zone 7 and a second aerobic zone 13, and the heterotrophic denitrification anoxic zone 7 is provided with a heterotrophic water distribution port 14; the third AO unit is composed of an autotrophic denitrification anoxic zone 8 and a third aerobic zone 15.
[0019] A plurality of fixed cages 10 are fixedly arranged in the autotrophic denitrification anoxic zone 8, and the fixed cages 10 are filled with autotrophic denitrification fillers.
[0020] Intercepting nets 9 are arranged at the water overflow between the second aerobic zone 13 of the last stage second AO unit and the autotrophic denitrification anoxic zone 8 and at the water overflow between the autotrophic denitrification anoxic zone 8 and the third aerobic zone 15, so as to avoid the autotrophic denitrification filler from flowing away with the water flow.
[0021] Hydraulic mixing and stirring systems 11 are arranged in the anaerobic zone 5, the heterotrophic denitrification anoxic zone 7 and the autotrophic denitrification anoxic zone 8. The hydraulic mixing and stirring systems 11 in the autotrophic denitrification anoxic zone 8 are arranged at intervals with the fixed cages 10.
[0022] The anaerobic zone 5 is provided with a sludge return port 3, which is connected to the secondary sedimentation tank through a sludge return conduit 4.
[0023] The fixed cages 10 are made of stainless steel wires, and the aperture must be smaller than the particle size of the internal filler. The fixed cages 10 are fixed to the bottom and side wall of the autotrophic denitrification anoxic zone 8. The filling volume of the autotrophic denitrification filler accounts for 30%-60% of the volume of the autotrophic denitrification anoxic zone 8, and is selected according to different forms of fillers. The autotrophic denitrification filler can use sulfur or iron-sulfur as medium, and porous hollow spheres and sponges can be used as carriers of the filler, which are in a suspended state in water.
[0024] The autotrophic denitrification anoxic zone 8 can be provided with an autotrophic water supply port 16, so that the water inflow will be subjected to heterotrophic denitrification; or the autotrophic denitrification anoxic zone 8 can not be provided with the autotrophic water supply port 16, so that no water inflow is provided, and autotrophic denitrification is performed. Both modes can be operated.
[0025] Embodiment 1,
[0026] In this embodiment, the autotrophic water supply port 16 is not provided.
[0027] The raw water enters the anaerobic zone 5 through the anaerobic water supply port 2, so as to provide the carbon source required for phosphorus release. The sludge in the secondary sedimentation tank enters the anaerobic zone 5 through the sludge return conduit (pipe) 4 and the sludge return port 3. In the anaerobic zone 5, the sludge and the raw water are fully mixed and reacted by the hydraulic mixing and stirring system 11, and then enter the first aerobic zone 6 to perform the aerobic phosphorus accumulation and nitrification reaction. The sludge-water mixture after the reaction enters the heterotrophic denitrification anoxic zone 7, and is fully mixed with the raw water entering the heterotrophic denitrification anoxic zone 7 through the heterotrophic water supply port 14 by the hydraulic mixing and stirring system 11 to perform the heterotrophic denitrification denitrification, and the denitrification mainly relies on the carbon source in the raw water to provide the electron donor. After the reaction is completed, the sludge-water mixture enters the second aerobic zone 13 to perform the nitrification reaction. In this way, after the multi-stage heterotrophic denitrification-nitrification in the multi-stage second AO unit, the sludge-water mixture enters the autotrophic denitrification anoxic zone 8 to perform the autotrophic denitrification denitrification, and the sulfur and iron in the autotrophic denitrification filler provide the electron donor to replace the traditional carbon source to perform the denitrification. After the denitrification is completed, the sludge-water mixture enters the third aerobic zone 15 to further remove the ammonia nitrogen and organic matter in the water, and then enters the secondary sedimentation tank.
[0028] Embodiment 2,
[0029] The embodiment sets up the autotrophic water distribution port 16. The sludge-water mixture is mixed with raw water through the hydraulic mixing stirring system 11 after the multi-stage heterotrophic denitrification-nitrification in the multi-stage second AO unit, and then enters the third aerobic zone 15 to further remove ammonia nitrogen and organic matter in the water, and then enters the secondary sedimentation tank.
[0030] The utility model can solve the problem that the existing sewage treatment plant is insufficient in carbon source of inlet water, and a large amount of carbon source is added, which leads to high operation cost; also can solve the problem that the autotrophic denitrification filler is simply set in the advanced treatment unit, and the denitrification effect is not good due to low water temperature. The utility model combines heterotrophic denitrification and autotrophic denitrification in the multi-stage AO unit, which can not only exert the high denitrification effect of the multi-stage AO, but also solve the problem of high operation cost. The autotrophic denitrification filler is set in the autotrophic denitrification anoxic zone 8, and air-water backwashing is not needed, so the energy-saving effect is obvious. The utility model does not need an internal reflux pump, and saves equipment and operation cost.
Claims
1. A multi-stage AO series-based synergistic autotrophic denitrification high-efficiency nitrogen removal system, characterized in that: A first AO unit, a plurality of second AO units and a third AO unit are sequentially connected in series in the biological tank (1); the first AO unit is composed of an anaerobic zone (5) and a first aerobic zone (6), and the anaerobic zone (5) is provided with an anaerobic water distribution port (2); the second AO unit is composed of a heterotrophic denitrification anoxic zone (7) and a second aerobic zone (13), and the heterotrophic denitrification anoxic zone (7) is provided with a heterotrophic water distribution port (14); the third AO unit is composed of an autotrophic denitrification anoxic zone (8) and a third aerobic zone (15).
2. The multi-stage AO series-based synergistic autotrophic denitrification high-efficiency nitrogen removal system according to claim 1, characterized in that: The autotrophic denitrification anoxic zone (8) is provided with an autotrophic water distribution port (16).
3. The multi-stage AO series-based high-efficiency denitrification system of claim 1 or 2, characterized in that: A plurality of fixed cages (10) are fixedly arranged in the autotrophic denitrification anoxic zone (8), and the fixed cages (10) are filled with autotrophic denitrification fillers.
4. The multi-stage AO series-based high-efficiency denitrification system of claim 3, characterized in that: An intercepting net (9) is arranged at a water passage between the second aerobic zone (13) of the last-stage second AO unit and the autotrophic denitrification anoxic zone (8) and at a water passage between the autotrophic denitrification anoxic zone (8) and the third aerobic zone (15).
5. The multi-stage AO series-based synergistic autotrophic denitrification high-efficiency nitrogen removal system according to claim 4, characterized in that: A hydraulic mixing and stirring system (11) is arranged in the anaerobic zone (5), the heterotrophic denitrification anoxic zone (7) and the autotrophic denitrification anoxic zone (8).
6. The multi-stage AO series-based synergistic autotrophic denitrification high-efficiency nitrogen removal system according to claim 5, characterized in that: The anaerobic zone (5) is provided with a sludge return port (3) connected to a secondary sedimentation tank through a sludge return channel (4).