High-efficiency phosphorus removal integrated process

Abstract

The application provides a high-efficiency phosphorus removal integrated process, comprising the following steps: S1, sewage to be treated enters a coagulation zone, and an aluminum salt coagulant is mixed with the sewage by a first stirrer; S2, effluent of the coagulation zone flows into a flocculation zone by itself, and a flocculant is mixed with the sewage by a second stirrer; S3, effluent of the flocculation zone flows into a water distribution area at the bottom of a sedimentation tank from both sides by itself, flows upward from the bottom in the water distribution area at the bottom of the sedimentation tank, then is precipitated in an inclined pipe filler layer, and then reaches the effluent weir of the surface layer of the sedimentation tank to flow into a sedimentation effluent channel, wherein sludge is discharged through a sludge discharge perforated pipe at the bottom of the water distribution area at the bottom of the sedimentation tank. The application has the beneficial effects that the coagulation-flocculation-precipitation-air flotation process is integrated, a complex structure is reasonably constructed, different scale phosphorus-containing pollutants are effectively removed, the land occupation is reduced, the phosphorus removal efficiency is high, and the functions of super-low phosphorus discharge are realized.

Description

Technical Field

[0001] This invention relates to wastewater treatment equipment, and more particularly to a highly efficient integrated phosphorus removal process. Background Technology

[0002] With the rapid development of urban construction, seasonal algal blooms are common in urban landscape water bodies, especially during the hot summer months when they occur frequently due to both external and internal pollution. Eutrophication of water bodies produces toxic substances and emits unpleasant odors; in severe cases, it can lead to the mass death of aquatic organisms and exacerbate water pollution. Phosphorus is a nutrient element for algal growth and a crucial limiting factor for controlling eutrophication. The OECD (Organisation for Economic Co-operation and Development) eutrophication threshold for total phosphorus is 0.035 mg / L. Traditional processes often result in high phosphorus concentrations, which, when the receiving water has poor flow or insufficient exchange capacity, easily lead to eutrophication and other water pollution problems.

[0003] Therefore, there is an urgent need to develop a highly efficient phosphorus removal device that can achieve ultra-low phosphorus emissions and reduce the phosphorus burden on water bodies. Summary of the Invention

[0004] To address the problems in the existing technology, this invention provides an integrated high-efficiency phosphorus removal process, which can achieve ultra-low phosphorus emissions and realize the goal of reducing phosphorus emissions in water bodies.

[0005] This invention provides a highly efficient integrated phosphorus removal process and a highly efficient integrated phosphorus removal device, comprising an integrated coagulation zone, a flocculation zone, a lower sedimentation zone, and an upper flotation zone. The coagulation zone is connected to an inlet pipe and has a first mixer installed within it. The outlet of the coagulation zone is connected to the inlet of the flocculation zone, and a second mixer is provided within the flocculation zone. The lower sedimentation zone includes a bottom water distribution area at the bottom, an inclined tube packing layer in the middle, a sedimentation tank effluent weir at the top surface, and a sedimentation effluent channel at the top surface. The sedimentation tank effluent weir and the sedimentation effluent channel are arranged adjacent to each other. The outlet of the flocculation zone is connected to the bottom of the sedimentation tank. The water inlets of the water distribution area are connected. The upper air flotation zone includes an air flotation inlet area, an air flotation mixing area, an air flotation separation area, and an air flotation outlet channel. The sedimentation outlet channel is adjacent to the air flotation inlet area. Water flows into the air flotation inlet area from the sedimentation outlet channel. The outlet of the air flotation inlet area is connected to the inlet of the air flotation mixing area. The outlet of the air flotation mixing area is connected to the inlet of the air flotation separation area. A lower perforated plate is provided in the air flotation separation area. The lower perforated plate is located between the air flotation separation area and the air flotation outlet channel. Water enters the air flotation outlet channel from the air flotation separation area through the lower perforated plate. The air flotation outlet channel is connected to an air flotation outlet pipe.

[0006] Based on the aforementioned high-efficiency integrated phosphorus removal device, the following steps are performed:

[0007] S1. The wastewater to be treated enters the coagulation zone, where aluminum salt coagulant is mixed with the wastewater by the first mixer;

[0008] S2. The effluent from the coagulation zone flows by gravity into the flocculation zone, where the flocculant is mixed with the wastewater by a second mixer.

[0009] S3. The effluent from the flocculation zone flows by gravity from both sides into the bottom water distribution area of ​​the sedimentation tank. In the bottom water distribution area of ​​the sedimentation tank, it flows upward from the bottom and then settles in the inclined tube packing layer. It then reaches the surface sedimentation tank effluent weir and flows into the sedimentation effluent channel. The sludge is discharged through the sludge discharge perforated pipe at the bottom of the bottom water distribution area of ​​the sedimentation tank.

[0010] S4. The sedimentation effluent flows by gravity into the flotation inlet area, where chitosan is added and micro-coagulation is carried out under the hydraulic stirring of the height difference.

[0011] S5. The water after micro-coagulation in the air flotation inlet zone enters the air flotation mixing zone from the bottom, mixes and adheres with the excess microbubbles released by the dissolved air releaser, forming a three-phase mixture of air, water and sludge, which flows vertically upward into the air flotation separation zone.

[0012] S6. The water in the air flotation separation zone enters the air flotation outlet channel through the lower perforated plate.

[0013] S7. The return liquid of the air flotation effluent from the air flotation outlet channel enters the multiphase pressurization pump through the return liquid inlet pipe. The multiphase pressurization pump cuts the large bubbles in the air-water mixture into small bubbles. Under the high pressure of the pump chamber, the small bubbles and water mix rapidly, so that the gas reaches saturation solubility. Then it enters the pressure stabilization pipe for pressure stabilization, and then is transported to the dissolved air release device through the dissolved air water pipe. The dissolved air release device releases the gas into the water under reduced pressure, generating a large number of microbubbles. In the vertical air flotation mixing zone, the sewage and microbubbles mix rapidly.

[0014] S8. Finally, the effluent after deep phosphorus removal is discharged through the air flotation effluent channel and then through the air flotation effluent pipe.

[0015] As a further improvement of the present invention, the high-efficiency integrated phosphorus removal device further includes a reflux liquid pipeline, which includes a reflux liquid inlet pipe, a multiphase pressurizing pump, a pressure stabilizing pipe, a dissolved air water pipe, and a dissolved air release device. The air flotation outlet pipe is connected to the reflux liquid inlet pipe, the reflux liquid inlet pipe is connected to the inlet of the multiphase pressurizing pump, the outlet of the multiphase pressurizing pump is connected to the inlet of the pressure stabilizing pipe, the outlet of the pressure stabilizing pipe is connected to the inlet of the dissolved air water pipe, and the outlet of the dissolved air water pipe is connected to the dissolved air release device. The dissolved air release device is located in the air flotation mixing zone.

[0016] As a further improvement of the present invention, the outlet of the flocculation zone includes a flocculation zone through hole and a flocculation zone culvert, and the flocculation zone through hole and the flocculation zone culvert are respectively connected to the inlets on both sides of the water distribution zone at the bottom of the sedimentation tank.

[0017] As a further improvement of the present invention, a sludge discharge perforated pipe is provided at the bottom of the water distribution area at the bottom of the sedimentation tank. The sludge discharge perforated pipe has a cross-shaped hole at an angle of 45 degrees. The sludge discharge perforated pipe is connected to a sludge discharge pipe, and a sludge discharge valve is provided on the sludge discharge pipe.

[0018] As a further improvement of the present invention, the inlet of the air flotation mixing zone is located at its bottom, and the outlet of the air flotation mixing zone is located at its top.

[0019] As a further improvement of the present invention, the high-efficiency integrated phosphorus removal device also includes a traveling automatic slag scraper, and a slag discharge trough is provided on the air flotation separation zone, and the slag discharge trough is connected to a slag discharge pipe.

[0020] As a further improvement of the present invention, the first mixer is a fast mixer, the second mixer is a slow mixer, and a micro-coagulation dosing mechanism is provided on the air flotation inlet area.

[0021] As a further improvement of the present invention, the coagulation zone and the flocculation zone are located in the upper layer of the high-efficiency phosphorus removal integrated device, and the water flows by gravity to undergo coagulation and flocculation reactions in sequence. The lower sedimentation zone is located in the lower layer of the high-efficiency phosphorus removal integrated device, and the upper air flotation zone is located in the upper layer of the high-efficiency phosphorus removal integrated device. Furthermore, there is a height difference between the effluent from the sedimentation outlet of the lower sedimentation zone and the inlet of the air flotation zone of the upper air flotation zone.

[0022] The beneficial effects of this invention are: it integrates coagulation-flocculation-sedimentation-air flotation processes, and through the rational construction of a complex structure, it enhances the effective removal of phosphorus-containing pollutants of different scales, achieving the functions of saving land, high phosphorus removal efficiency and ultra-low phosphorus emissions. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other solutions can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a plan view of an integrated high-efficiency phosphorus removal device according to the present invention;

[0025] Figure 2 for Figure 1 AA section view in the middle;

[0026] Figure 3 for Figure 1 BB cross-section diagram in the middle;

[0027] Figure 4 for Figure 1 CC cross-section view in the middle;

[0028] Figure 5 for Figure 1 DD cross-section view in the middle;

[0029] Figure 6 for Figure 1 EE cross-section diagram;

[0030] Figure 7 for Figure 1 FF cross-section diagram;

[0031] Figure 8 for Figure 1 GG cross-section diagram. Detailed Implementation

[0032] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0033] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0035] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0036] like Figures 1 to 8 As shown, a high-efficiency integrated phosphorus removal device includes a coagulation zone 2, a flocculation zone 3, a lower sedimentation zone 6, and an upper air flotation zone, wherein the coagulation zone 2, the flocculation zone 3, the lower sedimentation zone 6, and the upper air flotation zone are constructed in an integrated manner.

[0037] The coagulation zone 2 and the flocculation zone 3 are located in the upper layer of the structure, and the water flows by gravity and undergoes coagulation and flocculation reactions in sequence.

[0038] The lower sedimentation zone 6 is located in the lower layer of the structure. Wastewater after coagulation and flocculation reaction enters the lower inclined tube sedimentation zone through the corridor water distribution. Large floc particles that are easy to settle are removed here, while small, lightweight particles that are not easy to settle are discharged into the sedimentation effluent weir 12.

[0039] Inspection can be carried out through inspection well 30 in the lower sedimentation zone.

[0040] The upper air flotation zone is located on the upper part of the structure. A small amount of coagulant is added at the air flotation inlet. The sedimented effluent enters the air flotation distribution zone to form a height difference. Under the hydraulic flushing and stirring, the sewage and coagulant are fully mixed.

[0041] The coagulation zone 2 is connected to a water inlet pipe 1, and a high-speed mixer is installed in the coagulation zone 2.

[0042] The outlet of the coagulation zone 2 is connected to the inlet of the flocculation zone 3, and a slow mixer 5 is provided in the flocculation zone 3.

[0043] The lower sedimentation zone 6 includes a bottom water distribution zone 10 at the bottom of the sedimentation tank, an inclined tube packing layer 11 in the middle, a sedimentation tank effluent weir 12 at the top surface, and a sedimentation effluent channel 13 at the top surface.

[0044] The sedimentation tank effluent weir 12 is arranged adjacent to the sedimentation effluent channel 13, and the outlet of the flocculation zone 3 is connected to the inlet of the bottom water distribution zone 10 of the sedimentation tank.

[0045] The upper air flotation zone includes an air flotation inlet zone 7, an air flotation mixing zone 8, an air flotation separation zone 9, and an air flotation outlet channel 21.

[0046] The sedimentation outlet channel 13 is arranged adjacent to the air flotation inlet zone 7, and water flows into the air flotation inlet zone 7 through the sedimentation outlet channel 13.

[0047] The outlet of the air flotation inlet zone 7 is connected to the inlet of the air flotation mixing zone 8, and the outlet of the air flotation mixing zone 8 is connected to the inlet of the air flotation separation zone 9.

[0048] The air flotation separation zone 9 is provided with a lower perforated plate 20, which is located between the air flotation separation zone 9 and the air flotation outlet channel 21. Water enters the air flotation outlet channel 21 from the air flotation separation zone 9 through the lower perforated plate 20. The air flotation outlet channel 21 is connected to an air flotation outlet pipe 29.

[0049] The upper air flotation zone and the lower sedimentation zone 6 are isolated by upper and lower partitions 24 to avoid mutual disturbance between air flotation and sedimentation, which would affect the effluent. The sedimentation-air flotation process is connected in series to achieve sedimentation before air flotation, thereby improving the system's deep phosphorus removal efficiency.

[0050] The high-efficiency integrated phosphorus removal device also includes a reflux liquid pipeline, which includes a reflux liquid inlet pipe 15, a multiphase booster pump 16, a pressure stabilizing pipe 17, a dissolved air water pipe 18, and a dissolved air release device 19. The air flotation outlet pipe 29 is connected to the reflux liquid inlet pipe 15, the reflux liquid inlet pipe 15 is connected to the inlet of the multiphase booster pump 16, the outlet of the multiphase booster pump 16 is connected to the inlet of the pressure stabilizing pipe 17, the outlet of the pressure stabilizing pipe 17 is connected to the inlet of the dissolved air water pipe 18, and the outlet of the dissolved air water pipe 18 is connected to the dissolved air release device 19. The dissolved air release device 19 is located in the air flotation mixing zone 8.

[0051] The multiphase pressurization pump 16, also known as the multiphase flow pressurization pump, can be connected to the dissolved air tank. The multiphase flow pressurization pump pressurizes and dissolves gas in the return water. The gas and sewage are pressurized and mixed in the multiphase flow pressurization pump chamber, and then further dissolved and pressurized in the dissolved air tank to the pressure stabilizing pipe 17 for flow stabilization.

[0052] The effluent from the dissolved air tank is transported to multiple evenly distributed dissolved air releasers 19 via pressure stabilizing pipe 17 and dissolved air water pipe 18. The depressurized water is released into the water to generate a large number of microbubbles. In the vertical air flotation mixing zone 8, the sewage and microbubbles are rapidly mixed.

[0053] In the air flotation separation zone 9, low-density bubbles form a bubble flow that carries small particles upwards, which diffuse on the surface to form a bubble film, further separating and removing particles in the wastewater that are not easy to settle.

[0054] The outlet of the flocculation zone 3 includes a flocculation zone through hole 32 and a flocculation zone culvert 31, which are respectively connected to the inlets on both sides of the bottom water distribution zone 10 of the sedimentation tank.

[0055] The bottom of the water distribution area 10 at the bottom of the sedimentation tank is provided with a sludge discharge perforated pipe 25. The sludge discharge perforated pipe 25 has a cross-shaped hole at an angle of 45 degrees. The sludge discharge perforated pipe 25 is connected to a sludge discharge pipe 26. A sludge discharge valve 27 is provided on the sludge discharge pipe 26.

[0056] Multiple perforated discharge pipes 25 are used. The diameter of the perforated discharge pipe 25 is 200-300mm, the diameter of the circular opening is 20-30mm, and the spacing between the openings is 500mm. The sludge is discharged through the discharge pipe 26 by pressure difference. Each discharge pipe 26 is equipped with a discharge valve 27, and the discharge is rotated according to the sedimentation time.

[0057] The inlet of the air flotation mixing zone 8 is located at its bottom, and the outlet of the air flotation mixing zone 8 is located at its top.

[0058] The high-efficiency phosphorus removal integrated device also includes a traveling automatic slag scraper 23, and a slag discharge trough 22 is provided on the air flotation separation zone 9, and the slag discharge trough 22 is connected to a slag discharge pipe 28.

[0059] The air flotation inlet zone 7 is equipped with a micro-coagulation dosing mechanism 14.

[0060] A highly efficient integrated phosphorus removal process, using the aforementioned highly efficient integrated phosphorus removal device for wastewater treatment, specifically includes the following steps:

[0061] S1. The wastewater to be treated enters the coagulation zone 2, where aluminum salt coagulant is mixed with the wastewater by a high-speed mixer 4. The coagulation reaction time is 15-30 minutes.

[0062] S2. The effluent from coagulation zone 2 flows by gravity into flocculation zone 3, where flocculant (PAM) is mixed with the wastewater by a slow mixer 5. The flocculation reaction time is 15-30 minutes. The effluent from flocculation zone 3 flows by gravity from both sides through the flocculation zone through-hole 32 and the flocculation zone culvert 31 into the water distribution zone 10 at the bottom of the sedimentation tank.

[0063] S3, the effluent from flocculation zone 3 flows by gravity from both sides into the bottom distribution zone 10 of the sedimentation tank. In the bottom distribution zone 10, it flows upwards from the bottom, then settles in the inclined tube packing layer 11, and finally reaches the surface sedimentation tank effluent weir 12 for discharge, flowing into the sedimentation effluent channel 13. Sludge is discharged through the sludge discharge perforated pipe 25 at the bottom of the bottom distribution zone 10. The surface loading of the inclined tube packing layer 11 is 1.5-3m. 3 / m 2 h, the depth of the lower sedimentation zone 6 is 2.5-3m;

[0064] S4. The sedimentation outlet 13 flows by gravity into the air flotation inlet zone 7. Chitosan is added in the air flotation inlet zone 7 and micro-coagulation is carried out under the high-difference hydraulic stirring. Chitosan can increase the viscoelasticity of the air-water interface, improve the surface adhesion of microbubbles, promote the aggregation of small particles and colloidal particles, and reduce the merging and rupture of microbubbles, thereby increasing the removal effect of small particles.

[0065] S5. The water after micro-coagulation in the air flotation inlet zone 7 enters the air flotation mixing zone 8 from the bottom, where it mixes and adheres to the excess microbubbles released by the dissolved air releaser, forming a three-phase mixture of air, water, and sludge. This mixture flows vertically upward into the air flotation separation zone 9. In the air flotation separation zone 9, a large number of microbubbles in the wastewater adhere to suspended solids and diffuse to the water surface, forming a milky white sludge layer. Microbubbles and micro-coagulated flocs are continuously formed, capturing particulate matter in the residual water as they rise, further removing small-sized phosphorus-containing particles. The pollutant sludge is scraped to the sludge discharge trough 22 by a traveling automatic scraper 23.

[0066] S6. Water from the air flotation separation zone 9 enters the air flotation outlet channel 21 through the lower perforated plate 20. The lower perforated plate 20 has multiple round holes arranged in a square pattern, with a diameter of 5mm and a spacing of 10cm. The hydraulic load of the air flotation separation zone 9 is 5-10m³. 3 / m 2 h, the air flotation zone depth is 1.5-2.5m;

[0067] S7. 10-15% of the effluent from the flotation outlet channel 21 is returned to the multiphase booster pump 16 through the return liquid inlet pipe 15. The multiphase booster pump 16 cuts the large bubbles in the gas-water mixture into small bubbles. Under the high pressure of the pump chamber, the small bubbles and water are rapidly mixed to make the gas reach saturation solubility. Then it enters the pressure stabilizing pipe 17 for pressure stabilization. The residence time in the pressure stabilizing pipe 17 is 1-2 minutes. Then it is transported to the dissolved air release device 19 through the dissolved air water pipe 18. The dissolved air release device 19 releases the water under pressure to generate a large number of microbubbles. In the vertical flotation mixing zone 8, the sewage and microbubbles are rapidly mixed.

[0068] S8. Finally, the effluent after deep phosphorus removal is discharged through the air flotation effluent channel and then through the air flotation effluent pipe 29.

[0069] The present invention provides an integrated high-efficiency phosphorus removal device and process, which has the following advantages:

[0070] (1) Traditional sedimentation and flotation tanks are connected in series and occupy a large area. This invention uses the shallow pool theory to make full use of vertical space and adopts a double-layer duplex structure to build an integrated sedimentation and flotation tank, which is land-saving and has strong resistance to shock loads.

[0071] (2) Traditional sedimentation processes or magnetic coagulation sedimentation (high-density sedimentation tank) processes have a certain removal effect on phosphorus, but the effluent concentration can only reach 0.2-0.5 mg / L. With the improvement of water quality targets, relying solely on the above processes cannot meet the phosphorus concentration requirements of easily eutrophic water bodies. This invention has a high removal efficiency for phosphorus-containing pollutants with a large range of mesoscale distribution in wastewater, meets the ultra-low phosphorus discharge requirements, and can reduce the total phosphorus in the effluent to approximately below 0.03 mg / L.

[0072] The present invention provides an efficient integrated phosphorus removal device and process. Application scenario one is a wastewater deep treatment project with ultra-low phosphorus emission requirements, and application scenario two is deep phosphorus removal and circulation purification treatment for eutrophic landscape water bodies.

[0073] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A highly efficient integrated phosphorus removal process, characterized in that: A high-efficiency integrated phosphorus removal device is provided, comprising an integrated coagulation zone, a flocculation zone, a lower sedimentation zone, and an upper air flotation zone. The coagulation zone is connected to an inlet pipe and contains a first mixer. The outlet of the coagulation zone is connected to the inlet of the flocculation zone, and a second mixer is located within the flocculation zone. The lower sedimentation zone includes a bottom water distribution area, a middle inclined tube packing layer, a top surface sedimentation weir, and a top surface sedimentation outlet channel. The sedimentation weir and the sedimentation outlet channel are adjacent to each other. The outlet of the flocculation zone is connected to the inlet of the bottom water distribution area. The upper air flotation zone includes an air flotation inlet area, an air flotation mixing area, an air flotation separation area, and an air flotation outlet channel. The sedimentation outlet channel is adjacent to the air flotation inlet area. The water is separated by the sedimentation... The water flows into the flotation inlet area via the outlet channel. The outlet of the flotation inlet area is connected to the inlet of the flotation mixing area. The outlet of the flotation mixing area is connected to the inlet of the flotation separation area. A lower perforated plate is provided in the flotation separation area. The lower perforated plate is located between the flotation separation area and the flotation outlet channel. Water flows from the flotation separation area through the lower perforated plate into the flotation outlet channel. The flotation outlet channel is connected to a flotation outlet pipe. The coagulation zone and flocculation zone are located in the upper layer of the high-efficiency integrated phosphorus removal device. The water flows by gravity and undergoes coagulation and flocculation reactions sequentially. The lower sedimentation zone is located in the lower layer of the high-efficiency integrated phosphorus removal device. The upper flotation zone is located in the upper layer of the high-efficiency integrated phosphorus removal device. Furthermore, there is a height difference between the effluent from the sedimentation outlet channel of the lower sedimentation zone and the flotation inlet area of ​​the upper flotation zone. Based on the aforementioned high-efficiency integrated phosphorus removal device, the following steps are performed: S1. The wastewater to be treated enters the coagulation zone, where aluminum salt coagulant is mixed with the wastewater by the first mixer; S2. The effluent from the coagulation zone flows by gravity into the flocculation zone, where the flocculant is mixed with the wastewater by a second mixer. S3. The effluent from the flocculation zone flows by gravity from both sides into the bottom water distribution area of ​​the sedimentation tank. In the bottom water distribution area of ​​the sedimentation tank, it flows upward from the bottom and then settles in the inclined tube packing layer. It then reaches the surface sedimentation tank effluent weir and flows into the sedimentation effluent channel. The sludge is discharged through the sludge discharge perforated pipe at the bottom of the bottom water distribution area of ​​the sedimentation tank. S4. The sedimentation effluent flows by gravity into the flotation inlet area, where chitosan is added and micro-coagulation is carried out under the hydraulic stirring of the height difference. S5. The water after micro-coagulation in the air flotation inlet zone enters the air flotation mixing zone from the bottom, mixes and adheres with the excess microbubbles released by the dissolved air releaser, forming a three-phase mixture of air, water and sludge, which flows vertically upward into the air flotation separation zone. S6. The water in the air flotation separation zone enters the air flotation outlet channel through the lower perforated plate. S7. The return liquid of the air flotation effluent from the air flotation outlet channel enters the multiphase pressurization pump through the return liquid inlet pipe. The multiphase pressurization pump cuts the large bubbles in the air-water mixture into small bubbles. Under the high pressure of the pump chamber, the small bubbles and water mix rapidly, so that the gas reaches saturation solubility. Then it enters the pressure stabilization pipe for pressure stabilization, and then is transported to the dissolved air release device through the dissolved air water pipe. The dissolved air release device releases the gas into the water under reduced pressure, generating a large number of microbubbles. In the vertical air flotation mixing zone, the sewage and microbubbles mix rapidly. S8. Finally, the effluent after deep phosphorus removal is discharged through the air flotation effluent channel and then through the air flotation effluent pipe.

2. The high-efficiency integrated phosphorus removal process according to claim 1, characterized in that: In step S7, 10-15% of the effluent from the flotation outlet channel 21 is returned to the multiphase booster pump 16 through the return liquid inlet pipe 15.

3. The high-efficiency integrated phosphorus removal process according to claim 1, characterized in that: In step S1, the coagulation reaction time is 15-30 min; in step S2, the flocculation reaction time is 15-30 min.

4. The high-efficiency integrated phosphorus removal process according to claim 1, characterized in that: The high-efficiency integrated phosphorus removal device also includes a reflux liquid pipeline, which includes a reflux liquid inlet pipe, a multiphase pressurizing pump, a pressure stabilizing pipe, a dissolved air water pipe, and a dissolved air release device. The air flotation outlet pipe is connected to the reflux liquid inlet pipe, the reflux liquid inlet pipe is connected to the inlet of the multiphase pressurizing pump, the outlet of the multiphase pressurizing pump is connected to the inlet of the pressure stabilizing pipe, the outlet of the pressure stabilizing pipe is connected to the inlet of the dissolved air water pipe, and the outlet of the dissolved air water pipe is connected to the dissolved air release device. The dissolved air release device is located in the air flotation mixing zone.

5. The high-efficiency integrated phosphorus removal process according to claim 1, characterized in that: The outlet of the flocculation zone includes a flocculation zone through hole and a flocculation zone culvert, which are respectively connected to the inlets on both sides of the water distribution zone at the bottom of the sedimentation tank.

6. The high-efficiency integrated phosphorus removal process according to claim 1, characterized in that: The bottom of the water distribution area at the bottom of the sedimentation tank is provided with a sludge discharge perforated pipe. The sludge discharge perforated pipe has a cross-shaped hole at a 45-degree angle. The sludge discharge perforated pipe is connected to a sludge discharge pipe, and the sludge discharge pipe is provided with a sludge discharge valve.

7. The high-efficiency integrated phosphorus removal process according to claim 1, characterized in that: The inlet of the air flotation mixing zone is located at its bottom, and the outlet of the air flotation mixing zone is located at its top.

8. The high-efficiency integrated phosphorus removal process according to claim 1, characterized in that: The high-efficiency integrated phosphorus removal device also includes a traveling automatic slag scraper, and a slag discharge trough is provided on the air flotation separation zone, with a slag discharge pipe connected to the slag discharge trough.

9. The high-efficiency integrated phosphorus removal process according to claim 1, characterized in that: The first mixer is a high-speed mixer, the second mixer is a slow-speed mixer, and a micro-coagulation dosing mechanism is provided on the air flotation inlet area.

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