An anaerobic ammonia oxidation reactor

Abstract

The application discloses an anaerobic ammonia oxidation reactor, which comprises a reactor body, wherein the reactor body is in a cylindrical or cuboid structure, a water inlet and a sludge inlet are arranged at the bottom of the side wall, a floating sludge outlet is arranged at the middle of the side wall, a water outlet and an aeration air inlet are arranged at the upper part of the side wall, a breathing hole and a sludge recovery hole are arranged at the top, a water inlet distribution system is arranged at the bottom of the reactor body and adopts a perforated water distribution form, and an aeration system adopts a microporous aeration form and comprises one or more of an aeration main pipe, an aeration distribution pipe and a microporous aerator.

Description

Technical Field

[0001] This invention relates to the field of reactor technology, and more particularly to an anaerobic ammonia oxidation reactor. Background Technology

[0002] Biological denitrification is widely used in ammonia nitrogen wastewater treatment due to its advantages of high removal rate and low treatment cost. Among them, the traditional nitrification / denitrification (A / O) denitrification process is the most basic process form. Its principle is: first, under aerobic conditions, nitrifying bacteria oxidize ammonia nitrogen into nitrate, and then under anoxic conditions, denitrifying bacteria use organic matter (COD, carbon source) to reduce nitrate into nitrogen gas.

[0003] Anaerobic ammonia oxidation (A / O) is also a biological nitrogen removal process, but it differs from the traditional A / O process in that it utilizes a special type of bacteria—anaerobic ammonia oxidizing bacteria. In A / O, only about 50% of the ammonia nitrogen needs to be oxidized to nitrite, and the remaining ammonia nitrogen and nitrite react directly to form nitrogen gas under the catalysis of the A / O bacteria. Compared to the traditional A / O process, A / O has the following advantages: it is a fully autotrophic process requiring no external carbon source; it has low oxygen demand and low aeration energy consumption; and it saves tank volume and floor space. Especially with A / O reactors using granular sludge, the sludge concentration can reach 3-5 times that of flocculent sludge, resulting in higher volumetric loading and a smaller footprint.

[0004] The final product of biological denitrification is nitrogen gas. Most of the nitrogen gas diffuses into the water and then escapes through the liquid surface. However, some tiny nitrogen gas bubbles inevitably adhere to the surface of the granular sludge or exist inside the granules, causing the granular sludge to become lighter and difficult to settle, resulting in its loss with the effluent.

[0005] Patent application number CN201721014649.4 discloses an anaerobic ammonia oxidation granular sludge reactor, comprising a tank, a degassing sedimentation separator, a separation screen, and an effluent pump. Wastewater enters the tank and, after denitrification in the reaction chamber, flows to the integrated degassing sedimentation separator. First, gas separation occurs in the degassing zone, where the sludge-water mixture flows downwards. Then, the mixture flows into the sedimentation zone equipped with inclined plates or tubes, where granular sludge settles and returns to the reaction chamber through the sludge outlet. The water separated from the sludge is collected in an overflow tank and discharged from the reactor through the outlet. To recover the sludge lost in the effluent, a bypass is connected to the reactor's effluent pipe and an effluent pump, which pumps the effluent to the separation screen. The granular sludge retained on the screen returns to the reaction chamber, while flocculent bacteria and water return to the effluent overflow tank. While this method of sludge recycling is effective, it is an "end-of-pipe" treatment approach where sludge is lost first and then recycled, meaning the source of sludge loss remains uncontrolled. Furthermore, it can only recycle sludge from the bypass flow, not from the water discharged from the reactor. Therefore, it only provides some relief from sludge loss and cannot fundamentally solve the problem.

[0006] In addition, the reactor described above uses a mixing method that primarily relies on aeration and stirring, supplemented by mechanical stirring. Because the aerators and stirrers are at a certain height from the reactor bottom plate, heavier granular sludge may settle at the bottom, failing to fully contact the wastewater and thus affecting the treatment effect.

[0007] Therefore, we designed an anaerobic ammonia oxidation reactor to solve the above problems. Summary of the Invention

[0008] The purpose of this invention is to address the shortcomings of existing technologies by proposing an anaerobic ammonia oxidation reactor.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: An anaerobic ammonia oxidation reactor, comprising: The reactor body has an inlet and a sludge outlet at the bottom of the side wall, a sludge floating outlet in the middle of the side wall, an outlet and an aeration air inlet at the top of the side wall, and a breathing port and a sludge recovery port at the top. The water inlet distribution system is installed at the bottom of the reactor body and adopts a perforated water distribution form; The aeration distribution system adopts a microporous aeration method, including an aeration main pipe, an aeration distribution pipe, and microporous aerators; The upper separator is installed at the top of the reactor body and is used to collect the water, gas and mud mixture after the denitrification reaction and to separate the gas and floating mud in advance. The lower separator is installed at the bottom of the reactor body and is used to separate the granular sludge in the effluent from the upper separator by sedimentation. An air-lift mixing pipe, installed within the reactor body, is used to lift and mix sludge; A sludge pump is installed outside the reactor body, and the pump suction port is connected to the sludge port and the floating sludge port of the reactor body; A sludge filter, installed on top of the reactor body, is used to filter sludge from the sludge pump.

[0010] Preferably, one or more upper separators are installed, and the upper separator includes: The outer cylinder is cylindrical at the top with an overflow inlet at the top and conical at the bottom with an outlet. The inner cylinder is a cylinder concentric with the outer cylinder, with its top opening 200-800mm lower than the outer cylinder, and its bottom opening communicating with the outer cylinder; The vortex distributor 19 is installed inside the outer cylinder 17 and consists of a ring of umbrella-shaped plates. The angle between the plates and the generatrix of the umbrella cone is 10-60°. The plates overlap and have gaps that allow liquid to pass through. The top of the vortex distributor 19 is provided with a vent. The inner cylinder 18 is provided with a sludge-floating pipe that slopes downwards at 30-60° at the upper part. The sludge-floating pipe passes through the outer cylinder and is connected to the sludge-floating port of the reactor body.

[0011] Preferably, the lower separator is a fully enclosed type, comprising: The sedimentation module has a top plate with an inlet that connects to the outlet of the upper separator. The sludge hopper is equipped with a sludge return port at the bottom, which is connected to the air-lift mixing pipe; The sedimentation module has an outlet on its end plate, which is connected to the outlet of the reactor body.

[0012] Preferably, the precipitation module includes: The shell consists of two end plates, two side plates and a top plate; the internal partition is arranged longitudinally inside the shell to divide the sedimentation module into a first compartment and a second compartment, with the water flow path being "U" shaped. A horizontal partition divides the first compartment and the second compartment into an inlet area, a sedimentation area and an outlet area, and the horizontal partition is provided with water passage holes; An inclined plate is set in the sedimentation zone, with multiple layers arranged from top to bottom, running longitudinally through the entire sedimentation zone. The cross-section of the inclined plate is an inverted "V" shape.

[0013] Preferably, the bottom end of the air-lift mixing pipe is 0.5-2m away from the bottom plate of the reactor body, and the top end is open, 1-4m lower than the liquid level of the reactor body. An air release device is provided at the center of the air-lift mixing pipe 200-600mm from the bottom end, which is connected to the air-lift air distribution pipe.

[0014] Preferably, the sludge filter comprises: Filter screen, with a pore size of 0.2-0.5mm; A filtrate tank is used to collect the filtrate that has passed through a filter screen. Sludge collection tank, used to collect particulate sludge trapped on the filter screen; A frame is used to support the filter screen, filtrate tank, and sludge collection tank.

[0015] Preferably, the reactor body is either a cylindrical structure or a cuboid structure; When the reactor body is a cylindrical structure, the diameter is 4-20m and the height is 8-15m; When the reactor body is a cuboid structure, the side length is 4-20m and the height is 7-15m.

[0016] Preferably, the outer cylinder diameter of the upper separator is 400-1500mm, the inner cylinder diameter is 200-800mm, the total height is 1000-2000mm, and the surface load is u < 0.5m. 3 / (m 2 ·s).

[0017] Preferably, the lower separator is provided with 1-4 sludge hoppers, and the sludge hoppers are tilted at an angle of 50-60°.

[0018] Preferably, the inclined plates consist of 2-6 layers, with an inclination angle of 50-60°, a sludge return slit size of 50-150 mm, and a surface loading rate of 0.5-3 m² in the sedimentation zone. 3 / (m 2 The horizontal flow velocity is 1-7 mm / s, and the flow velocity through the water passage is <0.5 m / s.

[0019] Compared with the prior art, the beneficial effects of the present invention are: Multiple measures are employed to enhance degassing: First, in the upper separator, a cyclone distributor disperses the incoming water into droplets, increasing the gas-liquid contact area and facilitating the escape of free gas from the water into the gas phase. Second, the inertial collision of water flow on the umbrella-shaped plate promotes the separation of bubbles adhering to the surface of granular sludge. Third, for bubbles within the granular sludge that cannot be removed in the first two steps, the low density and easy floating of gas-laden sludge are utilized to cause them to accumulate in the inner cylinder. The gas is then discharged through the sludge pump and returned to the reactor. Fourth, the higher pressure at the bottom of the reactor converts the gas into a dissolved state, reducing the amount of gas carried by the mixed liquid entering the sedimentation module. Degassing is a prerequisite for sludge settling; enhanced degassing reduces sludge loss at the source and ensures stable reactor operation. Inside the upper separator, the incoming water is dispersed into droplets by the vortex distributor and falls into the annular area between the outer and inner cylinders, causing continuous disturbance to the liquid surface in this area and preventing the formation of a floating mud layer; while the inner cylinder is in a hydraulically static state, which is conducive to the accumulation of floating mud in the inner cylinder. The lower separator adopts a horizontal flow inclined plate sedimentation, with the water flow direction and sludge settling direction at an angle of 90°, which will not interfere with the downward sludge settling; the compartment design requires the wastewater to flow through the entire length of the U-shaped channel to reach the effluent area, preventing water flow short-circuiting and making higher use of the sedimentation area. The air-lift mixing pipe creates a reciprocating circulation flow between the sludge settled in the lower separator and the mixed liquid at the bottom of the reactor, preventing sludge from accumulating at the bottom of the reactor and forming a dead zone, thus improving the mixing effect. At the same time, the hydraulic shearing brought by the circulation flow helps to promote the formation of microbial aggregates, washing out flocculent sludge, and also prevents the sludge particles from being too large and affecting the transfer of the substrate to the deeper particles.

[0020] Sludge is periodically screened through a sludge filter to prevent the proliferation of flocculent bacteria in the reactor and to ensure the dominant growth of anaerobic ammonia-oxidizing bacteria. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of an anaerobic ammonia oxidation reactor proposed in this invention; Figure 2 This is a plan view of the upper separator of an anaerobic ammonia oxidation reactor proposed in this invention; Figure 3 This is a cross-sectional view of the upper separator of an anaerobic ammonia oxidation reactor proposed in this invention; Figure 4 This is a schematic diagram of a sludge filter in an anaerobic ammonia oxidation reactor proposed in this invention; Figure 5 This is a schematic diagram of the lower separator of an anaerobic ammonia oxidation reactor proposed in this invention; Figure 6 This is a side view of the lower separator of an anaerobic ammonia oxidation reactor proposed in this invention; Figure 7 This is a top view of the lower separator of an anaerobic ammonia oxidation reactor proposed in this invention.

[0022] In the diagram: 1 Reactor body, 2 Inlet water distribution system, 3 Aeration system, 4 Upper separator, 5 Lower separator, 6 Air lift mixing pipe, 7 Sludge pump, 8 Sludge filter, 10 Sludge inlet, 11, 12 Floating sludge inlet, 14 Aeration air inlet, 15 Breathing, 16 Sludge recovery port, 17 Outer cylinder, 18 Inner cylinder, 19 Swirl distributor, 20 Floating sludge pipe, 22 Sedimentation module, 23 Sludge hopper, 24 Top plate, 27 Sludge return port, 28 Two end plates, 29 Two side plates, 30 Internal partition, 31 First compartment, 32 Second compartment, 33 Horizontal partition, 34 Water passage hole, 35 Inclined plate, 36 Air release device, 37 Filter screen, 38 Filtration tank, 39 Sludge collection tank, 40 Frame. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0024] The purpose of this invention is to address the shortcomings of the existing technology by improving the degassing sedimentation separator and adopting multiple enhancement measures to effectively control sludge loss at the source. Simultaneously, the mixing method of the reactor has also been improved to achieve better mixing and hydraulic shearing effects, which is beneficial for increasing the denitrification reaction rate and maintaining sludge particle size.

[0025] Example 1

[0026] like Figure 1 As shown, an anaerobic ammonia oxidation reactor includes: a reactor body 1, an influent distribution system 2, an aeration system 3, an upper separator 4, a lower separator 5, an air-lift mixing pipe 6, a sludge pump 7, and a sludge filter 8.

[0027] The reactor body 1 is cylindrical in shape, made of corrosion-resistant carbon steel, with a diameter of 7m, a height of 9m, and an effective water depth of 8m. The bottom of the side wall is equipped with a water inlet and a sludge inlet 10, the middle of the side wall is equipped with a sludge floating inlet 12, the upper part of the side wall is equipped with a water outlet and an aeration air inlet 14, and the top is equipped with a vent 15 and a sludge recovery inlet 16.

[0028] The water distribution system 2 is installed at the bottom of the reactor 1. It adopts a perforated water distribution form with an opening diameter of 24mm and the center of the water distribution pipe is 0.25m away from the bottom plate.

[0029] Aeration system 3 adopts a microporous aeration method, including an aeration main pipe, an aeration distribution pipe, and microporous aerators. The center of the aeration distribution pipe is 0.25m away from the bottom plate.

[0030] The upper separator 4 is installed at the top of the reactor 1 to collect the water, gas, and sludge mixture after the denitrification reaction, and to pre-separate the gas and floating sludge, as shown in the attached diagram. Figures 2-3 As shown.

[0031] The upper separator 4 includes an outer cylinder 17, an inner cylinder 18, and a vortex water distributor 19.

[0032] The outer cylinder 17 has a cylindrical upper part with an overflow inlet at the top and a conical lower part with an outlet at the bottom. A vortex distributor 19 is installed inside the outer cylinder 17 and consists of a ring of umbrella-shaped plates. The angle between the plates and the generatrix of the umbrella cone is 45°. The plates overlap and have gaps to allow liquid to pass through. The top of the vortex distributor 19 has a vent. The inner cylinder 18 is a cylinder concentric with the outer cylinder 17, with its top opening 400mm lower than the outer cylinder and its bottom opening communicating with the outer cylinder 17. A sludge-floating pipe 20 is installed at the top of the inner cylinder 18, angled downwards at 45°. The sludge-floating pipe 20 passes through the outer cylinder and connects to the sludge-floating port 12 in the middle of the side wall of the reactor 1.

[0033] In this embodiment, a single upper separator 4 is installed inside reactor 1. The outer cylinder has a diameter of 800 mm, the inner cylinder a diameter of 300 mm, and the total height is 1500 mm. The top surface of the outer cylinder is flush with the liquid level. The surface loading u = 0.013 m. 3 / (m 2 .s).

[0034] The lower separator 5 is installed at the bottom of the reactor 1 and is used to settle and separate the granular sludge in the effluent from the upper separator 4, as shown in the attached diagram. Figures 5-7 As shown.

[0035] The lower separator 5 is fully enclosed and includes a sedimentation module 22 and a sludge hopper 23. The sedimentation module 22 has a top plate 24, on which an inlet is provided, which is connected to the outlet of the upper separator 4. The sludge hopper 23 has a sludge return port 27 at the bottom, which is connected to the air-lift mixing pipe 6 in the reactor. The sedimentation module 22 has an outlet on its end plate 28, which is connected to the outlet pipe 13 on the upper side wall of the reactor 1.

[0036] The housing of the sedimentation module 22 consists of two end plates 28, two side plates 29, and a top plate 24. An internal longitudinal partition 30 is provided inside to divide the module into a first compartment 31 and a second compartment 32. Water enters from the first compartment 31, deflects at 180° at the end of the first compartment 31 and enters the second compartment 32, and exits from the end of the second compartment 32. The water flow path is "U".

[0037] The sedimentation module 22 is also equipped with two horizontal partitions 33, which divide the compartment into an inlet area, a sedimentation area and an outlet area. The horizontal partitions 33 have water passage holes 34.

[0038] Five inclined plates 35 are installed vertically throughout the sedimentation zone, running from top to bottom. The cross-section of each inclined plate 35 is an inverted "V" shape, and the wastewater flows horizontally within the sedimentation zone. Sludge settles to the surface of the inclined plates 35 under gravity and then falls into the sludge hopper for collection through the sludge return slits between the inclined plates 35. The sludge return slits are 55 mm in size.

[0039] Two sludge hoppers are installed along the length of the sedimentation module 22, with the sludge hoppers tilted at an angle of 55°.

[0040] In this embodiment, a lower separator 5, with external dimensions of 4000×2200×3500mm, is installed inside reactor 1 and fixed to the side wall of the reactor by support beams. It includes five layers of inclined plates with an inclination angle of 50° and a sludge return slit size of 55mm. The surface loading of the sedimentation zone is 0.9m². 3 / (m 2 The horizontal flow velocity is 2.6 mm / s, and the flow velocity through the water passage is 0.05 m / s.

[0041] In this embodiment, a total of four air-lift mixing pipes 6, each with a diameter of 300 mm, are installed inside reactor 1. The service area of ​​a single air-lift mixing pipe is 9.6 m². 2 The bottom of the air-lift mixing pipe 6 is 0.7m from the bottom plate of the reactor, and the top is open, 2m lower than the reactor liquid level. Two of the air-lift mixing pipes 6 are connected at their bottoms to the two sludge return pipes of the lower separator 5, while the bottoms of the other two air-lift mixing pipes are directly open. An air release device 36 is installed at the center of the air-lift mixing pipe 6, 300mm from the bottom, and is connected to the air-lift distribution pipe.

[0042] The sludge pump 7 is installed outside the reactor 1. Its suction port is connected to the sludge inlet 10 at the bottom of the reactor 1 sidewall and the floating sludge pipe inlet 12 on the sidewall and in the middle. The pump outlet is connected to the sludge filter 8. The sludge pump 7 is a screw pump. In this embodiment, one sludge pump is used, with a flow rate of 5 m³ / s. 3 / h.

[0043] Reference Figure 4 In this reactor, a sludge filter 8 is installed at the top of the reactor 1 and consists of a filter screen 37, a filtrate tank 38, a sludge collection tank 39, and a frame 40. The filter screen 37 has a pore size of 0.42 mm. Sludge from the sludge pump 7 flows down from the top of the filter screen 37. Granular sludge is trapped on the filter screen 37 and carried by the water flow into the sludge collection tank 39, returning to the reactor through the sludge recovery pipe 16 at the top of the reactor 1. The filtrate containing flocculent bacteria passes through the filter screen 37, is collected in the filtrate tank 38, and is discharged together with the reactor effluent through a pipe.

[0044] In this embodiment, a sludge filter is provided, with a filter screen area of ​​1m². 2 .

[0045] Comparative Example 1 The anaerobic ammonia oxidation reactor, without the gas stripping mixing pipe, is otherwise the same as in Example 1; Comparative Example 2 The anaerobic ammonia oxidation reactor has a diameter of 8m, a height of 9m, and an effective water depth of 8m. It adopts an integrated degassing sedimentation separator. Part of the effluent is recycled as sludge through a separation screen. There is no air-lift mixing pipe. The rest is the same as in Example 1. Application Example 1 Example 1 and Comparative Examples 1 and 2 were used to treat ammonia nitrogen wastewater from the electronics industry, with a designed treatment capacity of 500 m³ for each example. 3 / d, the design influent total nitrogen is 1000mg / L.

[0046] Example 1, Comparative Example 1, and Comparative Example 2 were all inoculated with anaerobic ammonia oxidation granular sludge, with an average sludge concentration of 5.5 g / L.

[0047] The treatment effects of Example 1, Comparative Example 1, and Comparative Example 2 are shown in Table 1: Table 1. Comparison of treatment effects of anaerobic ammonia oxidation reactors in Example 1, Comparative Example 1 and Comparative Example 2

[0048] The changes in sludge during the operation of Example 1, Comparative Example 1, and Comparative Example 2 are shown in Table 2: Table 2. Comparison of sludge changes in Example 1, Comparative Example 1, and Comparative Example 2

[0049] As shown in Tables 1 and 2, the volumetric loading rate for treating ammonia nitrogen wastewater in this embodiment reaches 1.8 kg / (m³). 3 (d) The total nitrogen removal rate reached 85%, which is better than that of Comparative Example 1 and Comparative Example 2. During operation, the sludge concentration increased significantly while maintaining good particle size and sludge properties, and the sludge particle size was more uniform. This indicates that the improvements to the separator in this embodiment effectively prevented sludge loss and achieved a steady increase in sludge volume. The addition of the air-lift mixing pipe created better mixing and hydraulic shear conditions, improving mass transfer efficiency. Both ammonia nitrogen removal rate and total nitrogen removal rate were improved, flocculent sludge was washed out, and the sludge particle size distribution was more optimized.

[0050] Comparative Example 1 lacks an air-lift mixing tube, resulting in a slightly worse mass transfer effect compared to this embodiment. This is manifested in lower ammonia nitrogen removal rate and total nitrogen removal rate in the effluent, incomplete washing out of flocculent bacteria, and partial inhibition of the growth dominance of anaerobic ammonia oxidizing bacteria.

[0051] Comparative Example 2 uses an integrated degassing sedimentation separator without an air-lift mixing pipe, relying solely on aeration and stirring for mixing. This results in poor mass transfer, low ammonia nitrogen removal rate, and low total nitrogen removal rate. Although the effluent is equipped with a separation screen to recover sludge, significant sludge loss still occurs, and the sludge concentration gradually decreases. Sludge accumulation may exist at the bottom of the reactor, leading to poor sludge bed fluidization, insufficient washing out of flocculent sludge, excessive proliferation of miscellaneous bacteria crowding out the living space of anaerobic ammonia oxidizing bacteria, and sludge fragmentation with poor particle size.

[0052] Example 2

[0053] An anaerobic ammonia oxidation reactor includes: a reactor body 1, an influent distribution system 2, an aeration system 3, an upper separator 4, a lower separator 5, an air-lift mixing pipe 6, a sludge pump 7, and a sludge filter 8.

[0054] The reactor body 1 is a rectangular prism with a reinforced concrete structure, measuring 13m in length, 6.8m in width, and 8m in height, with an effective water depth of 7m. The bottom of the sidewall has an inlet and a sludge inlet 10, the middle of the sidewall has a sludge floating inlet 12, the upper part of the sidewall has an outlet and an aeration air inlet 14, and the top has a vent 15 and a sludge recovery inlet 16.

[0055] The water distribution system 2 is installed at the bottom of the reactor 1. It adopts a perforated water distribution form with an opening diameter of 21mm and the center of the water distribution pipe is 0.25m away from the bottom plate.

[0056] Aeration system 3 adopts a microporous aeration method, including an aeration main pipe, an aeration distribution pipe, and microporous aerators. The center of the aeration distribution pipe is 0.25m away from the bottom plate.

[0057] Two upper separators 4 are installed inside reactor 1. The outer cylinder has a diameter of 1000 mm, the inner cylinder has a diameter of 500 mm, and the total height is 2000 mm. The top surface of the outer cylinder is flush with the liquid level. The surface loading u = 0.024 m. 3 / (m 2 .s).

[0058] Two lower separators 5, each with dimensions of 5600×2200×3500mm, are installed inside reactor 1. Three sludge hoppers are provided, fixed to the reactor sidewalls by support beams. Five layers of inclined plates are incorporated, with an inclination angle of 50° and a sludge return slit size of 55mm. The surface loading of the sedimentation zone is 1.44m³. 3 / (m 2 The horizontal flow velocity is 6.24 mm / s, and the flow velocity through the water passage is 0.12 m / s.

[0059] Ten stripping mixing pipes 6, each 500 mm in diameter, are installed inside reactor 1. Each stripping mixing pipe serves a service area of ​​8.8 m². 2 The bottom of the air-lift mixing pipe 6 is 0.7m from the bottom plate of the reactor, and the top is open, 1m lower than the reactor liquid level. Six of the air-lift mixing pipes are connected at their bottoms to the six sludge return pipes of the lower separator, while the remaining four air-lift mixing pipes are open at the bottom. An air release device 36 is installed 300mm from the bottom of the air-lift mixing pipe 6 at its center, and is connected to the air-lift distribution pipe.

[0060] In this embodiment, two sludge pumps, screw pumps, are installed with a flow rate of 8m³ / h. 3 / h. Two sludge filters (8 units) are installed on top of reactor 1, each with a filter screen area of ​​1.6m². 2 The filter mesh size is 0.42mm.

[0061] Comparative Example 3 The anaerobic ammonia oxidation reactor is a reinforced concrete structure, 11m long, 8.5m wide, and 8m high, with an effective water depth of 7m. It employs an integrated degassing sedimentation separator without an air-lift mixing pipe. All effluent is discharged after sludge recovery via a filter screen with a mesh size of 0.42mm.

[0062] Application Example 2 Organic ammonia nitrogen wastewater was treated using Example 2 and Comparative Example 3, respectively. The reactor was designed to treat a flow rate of 2400 m³. 3 / d, total nitrogen concentration in influent 500mg / L.

[0063] The treatment effects of Example 2 and Comparative Example 3 are shown in Table 3: Table 3. Comparison of treatment effects of anaerobic ammonia oxidation reactors in Example 2 and Comparative Example 3

[0064] The changes in sludge during the operation of Example 2 and Comparative Example 3 are shown in Table 4: Table 4. Comparison of sludge changes between Example 2 and Comparative Example 3

[0065] As can be seen from Tables 3 and 4, the volumetric loading rate of ammonia nitrogen wastewater treated in Example 2 is close to 2 kg / (m³). 3 .d), the total nitrogen removal rate reached 80~86%, which is better than the control example 3. During the operation, the sludge concentration increased significantly, while maintaining good particle size and sludge properties, and the sludge particle size was more uniform.

[0066] Comparative Example 3 used an integrated degassing sedimentation separator without an air-lift mixing pipe. Its mass transfer effect was worse than that of Example 2, manifested in lower ammonia nitrogen and total nitrogen removal rates in the effluent. A significant drop in removal rates occurred at higher influent loads, indicating that the influent load exceeded the reactor's maximum processing capacity. All effluent was filtered to recover sludge, but the removal of flocculent bacteria was incomplete, inhibiting the growth of anaerobic ammonia oxidation granular sludge. The average sludge concentration gradually decreased, mainly due to the disintegration of granular sludge and the gradual flocculation of the sludge, leading to a decrease in the total sludge volume.

[0067] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention, all of which fall within the scope of protection claimed by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. An anaerobic ammonia oxidation reactor, characterized in that, include: The reactor body (1) has an inlet and a sludge inlet (10) at the bottom of the side wall, a sludge inlet (12) in the middle of the side wall, an outlet and an aeration air inlet (14) at the top of the side wall, and a breathing port (15) and a sludge recovery port (16) at the top. The water inlet distribution system (2) is installed at the bottom of the reactor body (1) and adopts a perforated water distribution form; The aeration distribution system (3) adopts a microporous aeration form, including an aeration main pipe, an aeration distribution pipe and a microporous aerator; The upper separator (4) is installed on the upper part of the reactor body (1) to collect the water, gas and mud mixture after the denitrification reaction and to separate the gas and floating mud in advance; The lower separator (5) is installed at the bottom of the reactor body (1) and is used to separate the granular sludge in the effluent of the upper separator (4). An air-lift mixing pipe (6) is installed inside the reactor body (1) for lifting and mixing sludge; A sludge pump (7) is installed outside the reactor body (1), and the pump suction port is connected to the sludge port (10) and the floating sludge port (12) of the reactor body (1). A sludge filter (8) is installed on top of the reactor body (1) for filtering sludge from the sludge pump (7); One or more upper separators (4) are installed, and the upper separator (4) includes: The outer cylinder (17) is cylindrical at the top, with an overflow inlet at the top and a conical shape at the bottom, with an outlet at the bottom. The inner cylinder (18) is a cylinder concentric with the outer cylinder (17), with its top opening 200-800mm lower than the outer cylinder (17) and its bottom opening communicating with the outer cylinder (17); The vortex distributor (19) is installed inside the outer cylinder (17) and consists of a ring of umbrella-shaped plates. The angle between the plates and the generatrix of the umbrella cone is 10-60°. The plates overlap and have gaps that allow liquid to pass through. The top of the vortex distributor (19) is provided with an air vent. The inner cylinder (18) is provided with a sludge-floating pipe (20) that slopes downward at 30-60°. The sludge-floating pipe (20) passes through the outer cylinder (17) and is connected to the sludge-floating port (12) of the reactor body (1).

2. The anaerobic ammonia oxidation reactor according to claim 1, characterized in that, The lower separator (5) is a fully enclosed type, including: The sedimentation module (22) has a top plate (24) on top, and the top plate (24) is provided with an inlet that is connected to the outlet of the upper separator (4); The sludge hopper (23) has a sludge return port (27) at the bottom, which is connected to the air-lift mixing pipe (6); The sedimentation module (22) has an outlet on its end plate (28) which is connected to the outlet of the reactor body (1).

3. The anaerobic ammonia oxidation reactor according to claim 2, characterized in that, The precipitation module (22) includes: The shell consists of two end plates (28), two side plates (29) and a top plate (24); the internal partition (30) is arranged longitudinally inside the shell to divide the sedimentation module (22) into a first compartment (31) and a second compartment (32), with the water flow path being "U" shaped; A transverse partition (33) divides the first compartment (31) and the second compartment (32) into an inlet area, a sedimentation area and an outlet area. The transverse partition (33) is provided with water passage holes (34). Inclined plate (35) is set in the sedimentation zone, with multiple layers from top to bottom, running longitudinally through the entire sedimentation zone. The cross-section of the inclined plate (35) is an inverted "V" shape.

4. The anaerobic ammonia oxidation reactor according to claim 1, characterized in that, The bottom end of the gas lift mixing pipe (6) is 0.5-2m away from the bottom plate of the reactor body (1), and the top end is open, which is 1-4m lower than the liquid level of the reactor body (1). An air release device (36) is provided in the center of the gas lift mixing pipe (6) 200-600mm from the bottom end, which is connected to the gas lift air distribution pipe.

5. The anaerobic ammonia oxidation reactor according to claim 1, characterized in that, The sludge filter (8) includes: Filter screen (37), with a pore size of 0.2-0.5mm; A filtrate tank (38) is used to collect the filtrate passing through the filter screen (37); Sludge collection tank (39) is used to collect particulate sludge trapped on filter screen (37); A frame (40) is used to support the filter screen (37), the filtrate tank (38), and the sludge collection tank (39).

6. The anaerobic ammonia oxidation reactor according to claim 1, characterized in that, The reactor body (1) is either a cylindrical structure or a cuboid structure; When the reactor body (1) is a cylindrical structure, the diameter is 4-20m and the height is 8-15m; When the reactor body (1) is a cuboid structure, the side length is 4-20m and the height is 7-15m.

7. The anaerobic ammonia oxidation reactor according to claim 1, characterized in that, The outer cylinder (17) of the upper separator (4) has a diameter of 400-1500 mm, the inner cylinder (18) has a diameter of 200-800 mm, the total height is 1000-2000 mm, and the surface load is u < 0.5 m. 3 / (m 2 ·s).

8. An anaerobic ammonia oxidation reactor according to claim 1, characterized in that, The lower separator (5) is equipped with 1-4 sludge hoppers, and the sludge hoppers are tilted at an angle of 50-60°.

9. An anaerobic ammonia oxidation reactor according to claim 3, characterized in that, The inclined plates (35) consist of 2-6 layers, with an inclination angle of 50-60°, a sludge return slit size of 50-150 mm, and a surface loading of 0.5-3 m² in the sedimentation zone. 3 / (m 2 The horizontal flow velocity is 1-7 mm / s, and the flow velocity through the water passage is <0.5 m / s.

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