Nitrogen and phosphorus removal reactor for domestic sewage

Abstract

The utility model provides a domestic sewage nitrogen and phosphorus removal reactor which comprises a reactor body which is divided into an anaerobic zone, an anoxic zone, an aerobic zone and a water outlet zone from bottom to top, the reactor body is of an integrated cylindrical barrel structure, and a water inlet and sludge return system is arranged in the anaerobic zone; a mixed liquid backflow system is arranged between the anoxic zone and the aerobic zone; an aeration system is arranged at the bottom of the aerobic zone, a filler is arranged at the top of the aerobic zone, the filler is a combined filler formed by arranging hydroformylated fiber polyester yarns with the diameter of 150 in rows and bundles, the distance between every two adjacent filler bundles is 200 mm, and the total length of each filler bundle is 2.5-3.5 m; the water outlet area is composed of a triangular weir and a water outlet groove, and treated sewage is finally conveyed to the next treatment unit through a water outlet pipe. The reactor with the integrated steel cylindrical barrel structure is adopted to replace a tank body with a steel concrete structure, the occupied area of the reactor is greatly reduced, the filler adopts a wiring harness column structure, and the effects of increasing the specific surface area and efficiently removing organic matters in sewage are achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to domestic sewage treatment technical field, concretely relates to a domestic sewage denitrification and phosphorus removal reactor. BACKGROUND

[0002] Domestic sewage is the sewage produced in people's daily life, including kitchen sewage, flushing water, bathing and washing sewage, etc., if these sewage is not treated before discharging, the nitrogen and phosphorus compounds in the sewage will pollute the environment, the polluted environment will destroy the ecological system, and even will lead to biological death, therefore, the sewage needs to be treated before discharging.

[0003] Generally, the domestic sewage of cities and towns is treated in large sewage treatment plants, while the number of people in villages and small towns, schools, hospitals and office buildings is small, and under the condition that the sewage production is small, it is not economical to construct a large steel concrete structure sewage treatment tank with large land occupation and large civil engineering investment. Therefore, we need to design a denitrification and phosphorus removal reactor that meets the condition of small sewage quantity, and the existing sewage treatment technology can treat the sewage, but there are still some problems, first, the water inlet, mixed liquid reflux and sludge reflux of the current sewage treatment equipment or structure are generally in the form of pipe submergence, the pipe is connected to the sewage treatment equipment or structure without a water distribution system, the water distribution is uneven, and the denitrification and phosphorus removal efficiency of microorganisms is affected. Second, the current sewage treatment technology needs to set a submersible mixer in the anaerobic zone and the anoxic zone as a mechanical stirrer to ensure that the sludge does not settle, and the power consumption is large. Third, the design depth of general sewage treatment equipment and structure is limited, and the effective water depth of the current integrated sewage treatment equipment is generally 3-3.5m due to transportation restrictions, and the effective water depth of the steel concrete tank body is generally 4-6m. The shallower the effective water depth is, the shorter the contact time of dissolved oxygen with water is, and the less oxygen dissolved into water is, which is not conducive to the growth of aerobic microorganisms. Therefore, we provide a domestic sewage denitrification and phosphorus removal reactor. SUMMARY

[0004] In view of the problems in the prior art, the utility model provides a domestic sewage denitrification and phosphorus removal reactor.

[0005] To achieve the above purpose, the utility model provides the following technical scheme:

[0006] A domestic sewage denitrification and phosphorus removal reactor, comprising:

[0007] The reactor body is distributed from bottom to top as an anaerobic zone, an anoxic zone, an aerobic zone and a water outlet zone;

[0008] The reactor body is an integrated cylindrical barrel structure, an anaerobic zone is provided with a water inlet and sludge reflux system; a mixed liquid reflux system is provided between the anoxic zone and the aerobic zone; an aeration system is provided at the bottom of the aerobic zone, and a filler is provided at the top of the aerobic zone; the filler is a combined filler of a column of bundles of Φ150 aldehyde fiber polyester filaments, the distance between two adjacent filler bundles is 200mm, and the total length of each filler bundle is 2.5-3.5m; the effluent zone is composed of a triangular weir and an effluent tank, the treated wastewater flows into the effluent tank through the weir, and finally is transported to the next treatment unit through the effluent system.

[0009] As a further improvement of the present scheme, the water inlet and sludge reflux system is composed of a water inlet pipe, a sludge reflux pipe and a water distribution system; the wastewater enters through the water inlet pipe, the reflux sludge enters through the sludge reflux pipe, and the wastewater and the reflux sludge are mixed and enter the water distribution system.

[0010] As a further improvement of the present scheme, the water distribution system includes a water distribution main pipe and a water distribution branch pipe; the water distribution branch pipe is fixed on both sides of the water distribution main pipe to form a circle covering the cross section of the reactor body; the wastewater and sludge mixture enter the water distribution main pipe and are then evenly distributed to each water distribution branch pipe to complete the water inlet and uniform water distribution.

[0011] As a further improvement of the present scheme, the aeration system is composed of an aeration main pipe, an aeration branch pipe and a microporous aerator; the aeration branch pipe is connected around the end of the aeration main pipe to form a square layout covering the cross section of the reactor body; the microporous aerator is installed at equal intervals on the aeration branch pipe.

[0012] As a further improvement of the present scheme, the mixed liquid reflux system is composed of a mixed liquid reflux pump and a mixed liquid water distribution system; the mixed liquid reflux pump draws the mixed liquid in the aerobic zone and enters the anoxic zone through the mixed liquid water distribution system.

[0013] As a further improvement of the present scheme, the filling rate of the filler in the aerobic zone is 50%-80%.

[0014] As a further improvement of the present scheme, the dissolved oxygen content in the anoxic zone is ≤0.5mg / L; the dissolved oxygen content in the aerobic zone is ≥2mg / L.

[0015] As a further improvement of the present scheme, an inspection manhole is provided on the reactor body, and the inspection manhole is located at a position 1m away from the bottom of the reactor body.

[0016] As a further improvement of the present scheme, a sludge discharge port is provided at the bottom of the reactor body, and the center of the sludge discharge port is 200mm away from the bottom of the reactor body.

[0017] As a further improvement of the present scheme, the effluent system is composed of an effluent pipe, and the treated wastewater flows into the next unit through the effluent pipe by gravity, and the flow rate of the effluent pipe is not less than 0.6m / s.

[0018] Compared with existing technologies, this utility model offers the following advantages: 1. The use of an integrated steel cylindrical reactor structure instead of a steel-concrete tank reduces investment; compared to steel-concrete tanks, the construction period is shortened and installation is convenient. Thanks to the cylindrical design, the reactor footprint is significantly reduced, making it particularly suitable for areas with limited land.

[0019] 2. The filler adopts a wire bundle structure, which has the effect of increasing the specific surface area and efficiently removing organic matter in sewage.

[0020] 3. The anoxic zone and anaerobic zone use a water distributor composed of a water distribution system to distribute water, which can play the role of hydraulic mixing and save the investment in submersible mixers.

[0021] 4. The depth of the aerobic zone of the reactor is large, which increases the oxygen transfer coefficient of dissolved oxygen, reduces the required air supply, reduces the air volume of the fan, and saves energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below with reference to the accompanying drawings.

[0023] Figure 1 It is a planar schematic diagram of the utility model;

[0024] Figure 2 It is a cross-sectional schematic diagram of the utility model;

[0025] Figure 3 This is a diagram of the water inlet and return sludge distribution system of the utility model;

[0026] Figure 4 It is a cross-sectional top view of the aeration system of the utility model.

[0027] Markings in the figure: 1-reactor body, 11-anaerobic zone, 12-anoxic zone, 13-aerobic zone, 14-outlet zone, 15-maintenance manhole, 16-sludge outlet, 2-filler, 3-water inlet and sludge return system, 31-water inlet pipe, 32-sludge return pipe, 33-water distribution system, 331-water distribution main pipe, 332-water distribution branch pipe, 4-aeration system, 41-aeration main pipe, 42-aeration branch pipe, 43-microporous aerator, 5-mixed liquor return system, 51-mixed liquor return pump, 52-mixed liquor distribution system, 6-outlet system. DETAILED DESCRIPTION

[0028] 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.

[0029] Example

[0030] like Figures 1-4 As shown, this embodiment provides a domestic sewage denitrification and phosphorus removal reactor, including a reactor body 1, which is distributed from bottom to top into an anaerobic zone 11, an anoxic zone 12, an aerobic zone 13 and a water outlet zone 14, and is provided with an inspection manhole 15 and a mud discharge port 16 at the bottom; the reactor body 1 is an integrated cylindrical barrel structure, specifically an integrated cylindrical steel tank body.

[0031] The anaerobic zone 11 is at the very bottom of the reactor. No dissolved oxygen enters this area. Its main function is for polyphosphate bacteria to release phosphorus anaerobically. The anoxic zone 12 is located between the anaerobic zone 11 and the aerobic zone 13. The dissolved oxygen content is controlled within 0.5 mg / L. Its main function is for microorganisms to carry out denitrification reactions to convert nitrite nitrogen and nitrate nitrogen into nitrogen gas. The aerobic zone 13 is located at the top of the reactor and is the aeration area of ​​the reactor. The dissolved oxygen content is not less than 2 mg / L. Its main function is for microorganisms to carry out nitrification reactions to convert ammonia nitrogen into nitrate and nitrite. At the same time, polyphosphate bacteria can absorb excessive phosphorus in this area, thereby removing total phosphorus from the sewage. The outlet area 14 consists of a triangular weir and an outlet trough. The treated sewage flows into the outlet trough from the weir mouth and is finally transported to the next treatment unit through the outlet pipe. The inspection manhole 15 is located about 1m from the bottom of the reactor to facilitate maintenance inside the reactor. The mud discharge port 16 is located at the bottom of the reactor, with the center 200 mm away from the bottom, and is used to discharge the biofilm (mud film, bottom mud) that falls off the filler.

[0032] The anaerobic zone 11 is equipped with a water inlet and sludge return system 3. A mixed liquor return system 5 connects the anoxic zone 12 and the aerobic zone 13. The aeration system 4 is located at the bottom of the aerobic zone 13, and the top is equipped with a packing 2. The packing 2 is a composite packing composed of Φ150 hydroxylated polyester fibers arranged in bundles, with a spacing of 200 mm between adjacent bundles and a total length of 2.5-3.5 meters per bundle. In practice, the packing ratio in the aerobic zone is 50%-80%, determined by the height of the aerobic zone in the reactor. The packing provides attachment points for microbial growth, forming a highly active biofilm with a large specific surface area on the packing surface, effectively removing organic matter from wastewater.

[0033] The filler adopts a wire bundle structure, which has the effect of increasing the specific surface area and efficiently removing organic matter in sewage.

[0034] The effluent zone 14 is composed of a triangular weir and an effluent tank, the treated sewage flows into the effluent tank through the weir, and is finally transported to the next treatment unit through the effluent system 6.

[0035] The integrated steel cylindrical barrel structure reactor is used instead of the steel-concrete structure pool body, which has less investment and shorter construction period compared with the steel-concrete structure pool body, and is easy to install. Due to the cylindrical barrel design, the reactor occupies less land area, and is particularly suitable for areas with limited land.

[0036] The influent and sludge return system 3 is composed of an influent pipe 31, a sludge return pipe 32 and a water distribution system 33; the sewage enters through the influent pipe 31, the return sludge enters through the sludge return pipe 32, and the sewage and the return sludge are mixed and enter the water distribution system 33.

[0037] The water distribution system 33 includes a water distribution main pipe 331 and water distribution branch pipes 332; the water distribution branch pipes 332 are fixed on both sides of the water distribution main pipe 331 to form a circle covering the cross section of the reactor body 1; the sewage and sludge mixture enters the water distribution main pipe 331 and is then evenly distributed to each water distribution branch pipe 332 to complete the influent and uniform water distribution.

[0038] The sludge return can ensure that the reactor body 1 maintains sufficient sludge concentration, ensuring the efficiency of biochemical reaction. After the return sludge and the sewage are in contact, the organic matter in the sewage is firmly adsorbed by the sludge, and then degraded in the reactor body 1, greatly improving the removal efficiency of organic matter. The water distribution system 33 evenly distributes the mixture of influent and return sludge to every corner of the cross section of the reactor body 1, ensuring that the working conditions of the reactor body 1 are consistent everywhere, and the water distribution system 33 also plays a role in hydraulic stirring, avoiding the large amount of sludge settling at the bottom of the reactor. Compared with the mechanical stirring in the anaerobic zone in the traditional design concept, the investment of the submersible mixer is saved.

[0039] The aeration system 4 is composed of an aeration main pipe 41, an aeration branch pipe 42 and a microporous aerator 43; the aeration branch pipe 42 is connected around the end of the aeration main pipe 41 to form a square layout covering the cross section of the reactor body 1; the microporous aerator 43 is installed at equal intervals on the aeration branch pipe 42.

[0040] Air enters the aerobic zone 13 in the reactor through the aeration main pipe 41, is then evenly distributed to each aeration branch pipe 42, and is finally sprayed out from the microporous aerator 43 installed on each branch pipe to form tiny bubbles, providing sufficient dissolved oxygen for the aerobic zone 13.

[0041] The mixed liquid return system 5 is composed of a mixed liquid return pump 51 and a mixed liquid water distribution system 52; the mixed liquid return pump 51 extracts the mixed liquid in the aerobic zone 13, which enters the anoxic zone 12 through the mixed liquid water distribution system 52.

[0042] The mixed liquor contains large amounts of nitrate and nitrite nitrogen, which, after refluxing, are degraded and purified into nitrogen gas by denitrifying bacteria in the anoxic zone, thus achieving denitrification. Similarly, the mixed liquor distribution system 52 evenly distributes the mixed liquor to every corner of the reactor body, ensuring consistent operating conditions throughout the reactor. Furthermore, the mixed liquor distribution system 52 provides hydraulic agitation, preventing sludge from settling to the bottom of the reactor. Compared to traditional designs that mechanically agitate the anoxic zone, this reduces investment in submerged mixers.

[0043] The outlet system 6 consists of an outlet pipe. After being treated, the sewage flows into the next unit by gravity through the outlet pipe. The flow rate of the outlet pipe is not less than 0.6m / s.

[0044] The above content is merely an example of the structure of the present invention. Technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A domestic sewage denitrification and phosphorus removal reactor, comprising: The reactor body (1) is divided into an anaerobic zone (11), an anoxic zone (12), an aerobic zone (13) and an effluent zone (14) from bottom to top; The invention is characterized in that the reactor body (1) is an integrated cylindrical barrel structure, the anaerobic zone (11) is provided with a water inlet and sludge return system (3); a mixed liquid return system (5) is provided between the anoxic zone (12) and the aerobic zone (13); an aeration system (4) is provided at the bottom of the aerobic zone (13), and a filler (2) is provided at the top, wherein the filler (2) is a combined filler of Φ150 aldehyded polyester fibers arranged in bundles, the distance between adjacent filler bundles is 200 mm, and the total length of each filler bundle is 2.5-3.5 m; the outlet zone (14) is composed of a triangular weir and an outlet trough, and the treated sewage flows into the outlet trough from the weir mouth and is finally transported to the next treatment unit through the outlet system (6).

2. A domestic sewage denitrification and phosphorus removal reactor according to claim 1, characterized in that: The water inlet and sludge return system (3) consists of a water inlet pipe (31), a sludge return pipe (32) and a water distribution system (33); sewage enters through the water inlet pipe (31), and return sludge enters through the sludge return pipe (32), and the sewage and return sludge contact and mix and enter the water distribution system (33).

3. A domestic sewage denitrification and dephosphorization reactor according to claim 2, characterized in that: The water distribution system (33) includes a water distribution main pipe (331) and water distribution branch pipes (332); the water distribution branch pipes (332) are fixed on both sides of the water distribution main pipe (331) to form a circumference covering the cross section of the reactor body (1); the sewage and sludge mixture enters the water distribution main pipe (331) and is then evenly distributed to each water distribution branch pipe (332), completing water intake and uniform water distribution.

4. A domestic sewage denitrification and phosphorus removal reactor according to claim 1, characterized in that: The aeration system (4) consists of an aeration main pipe (41), an aeration branch pipe (42), and a microporous aerator (43); the aeration branch pipe (42) surrounds and connects to the end of the aeration main pipe (41) to form a square layout covering the cross section of the reactor body (1); the microporous aerator (43) is installed on the aeration branch pipe (42) at equal intervals.

5. A domestic sewage denitrification and phosphorus removal reactor according to claim 1, characterized in that: The mixed liquid reflux system (5) is composed of a mixed liquid reflux pump (51) and a mixed liquid water distribution system (52); the mixed liquid reflux pump (51) extracts the mixed liquid from the aerobic zone (13) and enters the anoxic zone (12) through the mixed liquid water distribution system (52).

6. A domestic sewage denitrification and phosphorus removal reactor according to claim 1, characterized in that: The filling rate of the filler (2) in the aerobic zone (13) is 50%-80%.

7. A domestic sewage denitrification and phosphorus removal reactor according to claim 1, characterized in that: The dissolved oxygen content in the anoxic zone (12) is ≤0.5 mg / L; the dissolved oxygen content in the aerobic zone (13) is ≥2 mg / L.

8. The domestic sewage denitrification and phosphorus removal reactor according to claim 1, characterized in that: The reactor body (1) is provided with an inspection manhole (15), and the inspection manhole (15) is located 1 meter away from the bottom of the reactor body (1).

9. The domestic sewage denitrification and phosphorus removal reactor according to claim 1, characterized in that: A mud discharge port (16) is provided at the bottom of the reactor body (1), and the center of the mud discharge port (16) is 200 mm away from the bottom of the reactor body (1).

10. The domestic sewage denitrification and phosphorus removal reactor according to claim 1, characterized in that: The outlet system (6) consists of an outlet pipe. After being treated, the sewage flows into the next unit by gravity through the outlet pipe. The flow rate of the outlet pipe is not less than 0.6m / s.

Images