Efficient denitrification biological filter bed for treating low C / N reclaimed water

Abstract

The utility model discloses an efficient denitrification biological filter bed for treating low C / N reclaimed water, which comprises a water flow assembly, the water flow assembly comprises a filter tank, a water distribution well, a water distribution channel, a valve well, a water distribution main pipe, a water distribution branch pipe, a water outlet hole, a biological filter bed partition wall and a water collecting channel, the water distribution well is arranged in the middle of one side of the inner side wall of the filter tank, and the valve well is arranged in the water distribution branch pipe; a water distribution channel and a valve well are arranged in the water distribution well. According to the utility model, reducing electrons are provided by the denitrification filler, and an inorganic carbon source in water is used as a microbial carbon base, so that an autotrophic efficient denitrification environment with thiobacillus denitrificans as a main component is formed, and under the promotion of microorganisms, electron donors in water are further consumed, nitrate nitrogen / nitrite nitrogen is reduced into nitrogen, and the nitrogen / nitrite nitrogen conversion efficiency is improved. And finally, efficient removal of nitrate / nitrite under the condition of no external carbon source is realized, the biomass generated by the reaction is relatively low, and the method has the remarkable advantages of high denitrification efficiency, low operation cost, low sludge yield, no COD (Chemical Oxygen Demand) standard exceeding risk and the like.

Description

Technical field:

[0002] The utility model relates to the technical field of sewage treatment, in particular to a high-efficiency denitrification biological filter bed for treating low C / N recycled water. Background technology:

[0004] The mainstream process for deep removal of total nitrogen from tailwater from municipal sewage treatment plants, both domestically and internationally, is to use biochemical methods, build or renovate sewage treatment facilities to enhance denitrification, and ultimately achieve stable and effective total nitrogen removal. Specific approaches include extending the retention time of the anoxic tank, implementing multi-point water inlet, and implementing multi-stage AO processes to maximize the utilization of carbon sources in the raw water to improve the denitrification capacity of the anoxic tank; or using novel carbon sources with higher COD equivalents to enhance denitrification reactions; or enhancing terminal denitrification capacity. However, in the face of a lack of carbon sources in the raw water, additional carbon sources must still be added to ensure denitrification. However, improper addition not only fails to enhance denitrification but also increases the burden on the nitrification reaction and causes COD levels in the effluent to exceed standards. Therefore, a high-efficiency denitrification biofilter for treating low-C / N recycled water was proposed. Utility model content:

[0006] The purpose of the utility model is to provide a high-efficiency denitrification biological filter bed for treating low C / N recycled water, so as to solve one of the problems raised in the above background technology.

[0007] The utility model is implemented by the following technical scheme: a high-efficiency denitrification biological filter bed for treating low C / N recycled water, including a water flow component, the water flow component including a filter tank, a water distribution well, a water distribution channel, a valve well, a water distribution main pipe, a water distribution branch pipe, a water outlet hole, a biological filter bed partition wall and a water collection channel, a water distribution well is provided in the middle of one side of the inner wall of the filter tank, a water distribution channel and a valve well are provided inside the water distribution well, a water distribution main pipe penetrates the side of the inner wall of the valve well away from the water distribution channel, a plurality of water distribution branch pipes are connected to the outer wall of the water distribution main pipe, a plurality of water outlet holes are opened on the outer wall of the water distribution branch pipe, a biological filter bed partition wall is provided on the side of the filter tank away from the water distribution well, a water collection channel is provided on the side of the biological filter bed partition wall away from the filter tank, and a biological filter bed assembly is provided inside the filter tank near the outer side of the water distribution well.

[0008] As a further preferred embodiment of the present technical solution: the biological filter bed assembly includes an anti-seepage layer, a water distribution layer, a filler layer and a clean water layer; the inner bottom wall of the filter tank is provided with an anti-seepage layer, the upper surface of the anti-seepage layer is provided with a water distribution layer, the upper surface of the water distribution layer is provided with a filler layer, and the upper surface of the filler layer is provided with a clean water layer.

[0009] As a further preferred embodiment of the present technical solution: the water distribution main pipe and the water distribution branch pipe are arranged inside the water distribution layer.

[0010] As a further preferred embodiment of the present technical solution: a manual gate is installed at one end of the water distribution main pipe close to the valve well, and the manual gate is arranged inside the valve well.

[0011] As a further preferred embodiment of the present technical solution: the interior of the water distribution layer is filled with graded crushed stone fillers and zeolite fillers.

[0012] As a further preferred embodiment of the present technical solution: the interior of the packing layer is filled with denitrification packing, and aquatic plants are arranged on the upper surface of the packing layer.

[0013] As a further preferred embodiment of the present technical solution: the upper parts of both sides of the outer wall of the water distribution main pipe are connected with ventilation pipes, the tops of the ventilation pipes pass through the bottoms of the filler layer and the clean water layer, and a ventilation cap is installed on the top of the ventilation pipes.

[0014] As a further preferred embodiment of the present technical solution: a manhole cover is fixedly connected to the upper surface of the water distribution well.

[0015] Advantages of this utility model:

[0016] 1. The utility model provides reducing electrons through denitrification fillers and uses inorganic carbon sources in water as carbon base for microorganisms to form an autotrophic and efficient denitrification environment dominated by denitrifying Thiobacillus. Under the promotion of microorganisms, electron donors in water are further consumed to reduce nitrate nitrogen / nitrite nitrogen to nitrogen gas, ultimately achieving efficient nitrate / nitrite removal without an external carbon source, and the biomass produced by the reaction is low, with significant advantages such as high denitrification efficiency, low operating cost, low sludge production, and no risk of COD exceeding the standard.

[0017] 2. Compared with traditional wetlands, the present invention has a high total nitrogen load, with a total nitrogen reduction load of about 20 to 100 g / (m2·d), and occupies a small area, which is about 40% of the traditional wetland, effectively solving the problem of large area occupied by traditional wetlands.

[0018] 3. The utility model overflows the water through the clear water layer, and there is no need to set a water collection pipe on the surface, which reduces investment and facilitates the maintenance of the biofilter bed in the later stage and the supplement of sulfur element in the high-efficiency denitrification filler. Description of the drawings:

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0022] Figure 2 This is a schematic diagram of the cross-section structure of the water distribution well and biological filter bed assembly of the utility model;

[0023] Figure 3 This is a schematic diagram of the structure of the water distribution main pipe and water distribution branch pipe of the utility model;

[0024] Figure 4 This is a schematic diagram of the cross-sectional structure of the water distribution branch pipe of the present utility model.

[0025] In the figure: 1. Water flow component; 2. Biofilter bed component; 11. Filter tank; 12. Water distribution well; 13. Water distribution channel; 14. Valve well; 15. Water distribution main pipe; 16. Water distribution branch pipe; 17. Water outlet; 18. Biofilter bed partition wall; 19. Water collection channel; 20. Anti-seepage layer; 21. Water distribution layer; 22. Filling layer; 23. Clear water layer; 24. Manual gate; 25. Graded crushed stone filler; 26. Zeolite filler; 27. Denitrification filler; 28. Aquatic plants; 29. Vent pipe; 30. Vent cap; 31. Manhole cover. Specific implementation method:

[0027] 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.

[0028] Example

[0029] See also Figure 1-4, the present utility model provides a technical solution: an efficient denitrifying biological filter bed for treating low C / N reclaimed water, including a water flow component 1. The water flow component 1 includes a filtration tank 11, a distribution well 12, a distribution channel 13, a valve well 14, a main water distribution pipe 15, branch water distribution pipes 16, water outlet holes 17, a biological filter bed partition wall 18, and a collection channel 19. In the middle of one side of the inner wall of the filtration tank 11, a distribution well 12 is provided. Inside the distribution well 12, a distribution channel 13 and a valve well 14 are provided. On the side of the inner wall of the valve well 14 away from the distribution channel 13, a main water distribution pipe 15 penetrates through. On the outer wall of the main water distribution pipe 15, a plurality of branch water distribution pipes 16 are connected. On the outer wall of the branch water distribution pipes 16, a plurality of water outlet holes 17 are provided. On the side of the filtration tank 11 away from the distribution well 12, a biological filter bed partition wall 18 is provided. On the side of the biological filter bed partition wall 18 away from the filtration tank 11, a collection channel 19 is provided. Inside the filtration tank 11, near the outside of the distribution well 12, a biological filter bed component 2 is provided. The size of the distribution channel 13 is 0.6m×1.3m, the size of the valve well 14 is 1.3×1.3m, and the depth is 2.5m. The width of the collection channel 19 is 1m and the depth is 2.2m. The reclaimed water enters the distribution channel 13 in the distribution well 12. After the water level in the distribution channel 13 reaches a certain elevation, it overflows into the valve well 14 and is distributed to each branch water distribution pipe 16 through the main water distribution pipe 15 connected by the valve well 14. The main water distribution pipe 15 and the branch water distribution pipes 16 adopt a "rich" - shaped water distribution method. The branch water distribution pipes 16 adopt perforated flower pipes. The incoming water is evenly distributed to the biological filter bed component 2 through the water outlet holes 17 on the branch water distribution pipes 16 for treatment, and finally overflows into the collection channel 19 through the biological filter bed partition wall 18 and is discharged into the external water body.

[0030] In this embodiment, specifically: the biological filter bed component 2 includes an anti - seepage layer 20, a water distribution layer 21, a filler layer 22, and a clear water layer 23. The anti - seepage layer 20 is provided on the inner bottom wall of the filtration tank 11. On the upper surface of the anti - seepage layer 20, a water distribution layer 21 is provided. On the upper surface of the water distribution layer 21, a filler layer 22 is provided. On the upper surface of the filler layer 22, a clear water layer 23 is provided. The total nitrogen volume load of the biological filter bed component 2 is 0.05 kg / (d·m 3 ), the hydraulic retention time is 2 h, and the treated water volume is 6000 m 3 / d.

[0031] In this embodiment, specifically: the main water distribution pipe 15 and the branch water distribution pipes 16 are arranged inside the water distribution layer 21. Due to the main water distribution pipe 15 and the branch water distribution pipes 16 being located in the water distribution layer 21, the water flows from the bottom to the top of the biological filter bed, flowing through the filler layer 22 in sequence, and finally being collected by the clear water layer 23 at the top and overflowing into the collection channel 19 through the biological filter bed partition wall 18 and then discharged into the external water body.

[0032] In this embodiment, specifically: a manual gate 24 is installed at one end of the water distribution main pipe 15 close to the valve well 14, and the manual gate 24 is arranged inside the valve well 14. The manual gate 24 installed on the water distribution main pipe 15 can facilitate the adjustment of the water inlet volume.

[0033] In this embodiment, specifically: the interior of the water distribution layer 21 is filled with graded crushed stone filler 25 and zeolite filler 26, the thickness of the water distribution layer 21 is 0.4m, the particle size of the graded crushed stone filler 25 filled in the water distribution layer 21 is 16-32mm, and the particle size of the zeolite filler 26 is 8-16mm.

[0034] In this embodiment, specifically: the interior of the packing layer 22 is filled with a denitrifying filler 27, and the upper surface of the packing layer 22 is provided with aquatic plants 28. The thickness of the packing layer 22 is 0.5m, and the particle size of the denitrifying filler 27 filled in the packing layer 22 is 8-12mm. The denitrifying filler 27 is synthesized from sulfur and limestone into high-porosity slow-release spherical solid particles. Denitrifying Thiobacillus uses sulfide or elemental sulfur in the denitrifying filler 27 as an electron donor to reduce nitrate to nitrogen gas, thereby achieving efficient nitrate / nitrite removal without an external carbon source. The aquatic plants 28 are reeds, yellow irises, and cattails, and the planting density is 15 plants / m 2 .

[0035] In this embodiment, specifically: the upper parts of both sides of the outer wall of the water distribution main pipe 15 are connected with ventilation pipes 29, the top of the ventilation pipe 29 passes through the bottom sides of the filler layer 22 and the clean water layer 23, and a ventilation cap 30 is installed on the top of the ventilation pipe 29. The ventilation pipe 29 adopts a DN110 UPVC pipe, and a ventilation cap 30 is installed on the top. The ventilation cap 30 is 300mm higher than the clean water layer 23.

[0036] In this embodiment, specifically: a manhole cover 31 is fixedly connected to the upper surface of the water distribution well 12 , and the manhole cover 31 protects the interior of the water distribution well 12 .

[0037] Working principle or structural principle, when in use, the recycled water enters the distribution channel 13 in the water distribution well 12, and the water level in the distribution channel 13 reaches a certain elevation and overflows into the valve well 14. By opening the manual gate 24, the recycled water in the valve well 14 flows into the water distribution branch pipes 16 through the water distribution main pipe 15, and the incoming water is evenly distributed to the water distribution layer 21 in the biological filter bed assembly 2 along the outlet holes 17 on the water distribution branch pipes 16. The water flows from the water distribution layer 21 to the top, and flows through the packing layer 22 in turn. The high-porosity slow-release spherical solid particle denitrification filler 27 filled with sulfur and limestone inside the packing layer 22 reduces nitrate to nitrogen, thereby realizing efficient nitrate / nitrite removal without an external carbon source. Finally, it flows into the top clear water layer 23 and is collected. After overflowing through the biological filter bed partition wall 18, it enters the collection channel 19 and is discharged to the external water body.

[0038] The purified water source in this embodiment is the tail water of the sewage treatment plant. The water quality of the project inlet water complies with the Beijing local standard "Water Pollutant Discharge Standard for Urban Sewage Treatment Plants" (DB11 / 890-2012) B standard (TN≤15mg / L). The project effluent is used for river ecological replenishment, TN≤10mg / L.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-efficiency denitrification biofilter for treating low C / N recycled water, characterized in that: The invention comprises a water flow component (1), wherein the water flow component (1) comprises a filter tank (11), a water distribution well (12), a water distribution channel (13), a valve well (14), a water distribution main pipe (15), a water distribution branch pipe (16), a water outlet (17), a biological filter bed partition wall (18) and a water collection channel (19), wherein a water distribution well (12) is provided in the middle of one side of the inner wall of the filter tank (11), a water distribution channel (13) and a valve well (14) are provided inside the water distribution well (12), and the inner wall of the valve well (14) is away from the water distribution channel (13). A water distribution main pipe (15) passes through one side of the water distribution main pipe (15), a plurality of water distribution branch pipes (16) are connected to the outer wall of the water distribution branch pipe (16), a plurality of water outlet holes (17) are opened on the outer wall of the water distribution branch pipe (16), a biological filter bed partition wall (18) is provided on the side of the filter tank (11) away from the water distribution well (12), a water collection channel (19) is provided on the side of the biological filter bed partition wall (18) away from the filter tank (11), and a biological filter bed assembly (2) is provided inside the filter tank (11) near the outer side of the water distribution well (12); The biological filter bed assembly (2) comprises an impermeable layer (20), a water distribution layer (21), a packing layer (22) and a clear water layer (23); the inner bottom wall of the filter tank (11) is provided with the impermeable layer (20); the upper surface of the impermeable layer (20) is provided with the water distribution layer (21); the upper surface of the water distribution layer (21) is provided with the packing layer (22); and the upper surface of the packing layer (22) is provided with the clear water layer (23); The interior of the packing layer (22) is filled with a denitrifying filler (27), and aquatic plants (28) are arranged on the upper surface of the packing layer (22). The denitrifying filler (27) filled in the packing layer (22) has a particle size of 8 to 12 mm, and the denitrifying filler (27) is a high-porosity slow-release spherical solid particle synthesized from sulfur and limestone.

2. The high-efficiency denitrification biological filter bed for treating low C / N recycled water according to claim 1, characterized in that: The water distribution main pipe (15) and the water distribution branch pipe (16) are arranged inside the water distribution layer (21).

3. The high-efficiency denitrification biological filter bed for treating low C / N recycled water according to claim 1, characterized in that: A manual gate (24) is installed at one end of the water distribution main pipe (15) close to the valve well (14), and the manual gate (24) is arranged inside the valve well (14).

4. The high-efficiency denitrification biological filter bed for treating low C / N recycled water according to claim 1, characterized in that: The interior of the water distribution layer (21) is filled with graded crushed stone filler (25) and zeolite filler (26).

5. The high-efficiency denitrification biological filter bed for treating low C / N recycled water according to claim 1, characterized in that: The upper portions of both sides of the outer wall of the water distribution main pipe (15) are connected to ventilation pipes (29), the top of the ventilation pipe (29) passes through the bottom of the packing layer (22) and the clear water layer (23), and a ventilation cap (30) is installed on the top of the ventilation pipe (29).

6. The high-efficiency denitrification biological filter bed for treating low C / N recycled water according to claim 1, characterized in that: A well cover (31) is fixedly connected to the upper surface of the water distribution well (12).

Images