Oxygen gradient self-coupled granular sludge partition reactor

Abstract

The present application belongs to the technical field of sewage treatment, and particularly relates to an oxygen gradient self-coupling granular sludge partition reactor, which comprises a reactor body, the reactor body is a vertically arranged tower structure, an aeration system, a water distribution system, a partition assembly, a three-phase separator, a gas collection assembly, a water outlet assembly and a sludge discharge port are arranged in the reactor body, wherein the partition assembly is arranged in at least one layer, and the partition assembly divides the inner cavity of the reactor body into a first reaction functional zone and a second reaction functional zone which are connected in series; the partition assembly comprises PET geotextile, and a grid support plate is arranged on the upper and lower sides of the PET geotextile; the present application integrates the functions of aeration, reaction, separation and water outlet in one body through the vertical tower structure, realizes efficient energy saving of the sewage treatment process, and utilizes the oxygen gradient self-coupling mechanism in the internal aerobic granular sludge to simultaneously complete nitrification and denitrification in a single reactor, so that the traditional nitrification liquid internal reflux and sludge reflux system are not needed, and the energy consumption and operation cost are significantly reduced.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment technology, specifically relating to an oxygen gradient self-coupled granular sludge partitioned reactor. Background Technology

[0002] With the acceleration of urbanization and increasingly stringent environmental protection requirements in my country, efficient, energy-saving, and stable wastewater treatment technologies have become an urgent need in the field of water pollution control. The activated sludge process and its derivative processes are currently the most widely used wastewater treatment technologies in the world. Among them, the traditional anaerobic (anoxic)-aerobic (AO) process and the membrane bioreactor (MBR) process are two representative technologies.

[0003] The AO process requires sludge recirculation, and the anaerobic or anoxic zone needs agitation. If denitrification is required, nitrification liquor recirculation is also necessary, with recirculation ratios typically reaching 200% to 400%. The process is complex and energy-intensive. Furthermore, the sludge concentration is relatively low, resulting in a low overall organic load and a large footprint, leading to high civil engineering costs. Additionally, the system uses ordinary flocculent sludge with poor settling properties, making solid-liquid separation in the secondary sedimentation tank difficult, increasing the suspended solids concentration in the effluent, and even causing sludge loss, thus affecting the stable operation of the system.

[0004] MBR (Membrane Bioreactor) technology is a highly efficient wastewater treatment process that combines membrane separation and biological treatment technologies. It completely replaces the secondary sedimentation tank with microfiltration or ultrafiltration membrane modules, achieving separation of sludge retention time and hydraulic retention time. This process offers advantages such as excellent effluent quality, small footprint, high sludge concentration, and strong load resistance. However, membrane usage and replacement costs are high, and chemical cleaning is required, making operation and maintenance complex. Furthermore, to mitigate membrane fouling, extensive aeration is needed to scrub the membrane surface, with this energy consumption accounting for 30% to 50% of the total system energy consumption, resulting in high operating costs. In addition, this process is highly sensitive to sharp impurities in the influent, requiring meticulous pretreatment, which increases the construction and operating costs of the pretreatment unit. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an oxygen gradient self-coupled granular sludge partitioned reactor that is as compact and efficient as an MBR, producing excellent effluent quality, while overcoming its drawbacks of membrane fouling and high energy consumption. Furthermore, it should possess the advantages of simple management inherent in traditional AO processes, and solve the problems of large footprint, complex processes, and low efficiency associated with AO processes.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A self-coupled oxygen gradient granular sludge partitioned reactor is provided, including a reactor body, which is a vertically arranged tower structure. The reactor body contains, from bottom to top, an aeration zone, a water distribution zone, a biological reaction zone, a three-phase separation zone, a sedimentation zone, and an effluent zone. A sludge discharge port is provided on one side of the reactor body.

[0008] An aeration system is installed at the bottom of the reactor body, located in the aeration zone. A water distribution system is installed above the aeration system, located in the water distribution zone.

[0009] The bioreactor zone is equipped with a partition component, with at least one layer of the partition component. The partition component is horizontally installed inside the reactor body, dividing the inner cavity of the reactor body into a first reaction functional zone and a second reaction functional zone connected in series. The partition component includes PET geotextile, and grid support plates are installed on the upper and lower sides of the PET geotextile.

[0010] A three-phase separator is installed at the top of the reactor body. The three-phase separator is located in the three-phase separation zone and above the separation component. The sedimentation zone is located above the three-phase separator. The water outlet of the three-phase separator is connected to the water outlet component, which is located in the water outlet zone. The gas outlet of the three-phase separator is connected to the gas collection component.

[0011] The beneficial effects of adopting the above technical solution are as follows: This oxygen gradient self-coupled granular sludge partitioned reactor integrates aeration, reaction, separation, and effluent functions into one vertical tower structure, achieving high efficiency and energy saving in the wastewater treatment process. It significantly reduces the floor space required, simplifies the structure, and improves space utilization. Furthermore, by utilizing the oxygen gradient self-coupling mechanism within the aerobic granular sludge, nitrification and denitrification reactions are completed simultaneously within a single reactor, eliminating the need for traditional nitrification liquor recirculation and sludge recirculation systems, thus significantly reducing energy consumption and operating costs. Simultaneously, it eliminates the need for expensive membrane modules, fundamentally avoiding membrane fouling, high maintenance costs, and energy consumption associated with membrane cleaning. The reactor body adopts a vertically arranged tower structure, highly integrating the biological reaction zone, sedimentation zone, and three-phase separator into a single tower structure, significantly reducing the footprint, simplifying connecting pipes, and improving space utilization. The aeration and water distribution systems located at the bottom of the reactor body control the aeration intensity to meet the biological oxygen demand. Simultaneously, the aeration system works in conjunction with the water distribution system to ensure uniform wastewater rise and dynamic hydraulic shear balance, maintaining the formation and stability of granular sludge, preventing clogging and sludge loss, thus ensuring the continuity and efficiency of the wastewater treatment process. The partition components in the biological reaction zone utilize PET geotextile to achieve functional zoning, allowing water and small molecules to pass through. The surface of the PET geotextile provides an ideal environment for microbial attachment and growth, forming a biofilm and constructing a "dynamic filter cake layer," effectively trapping microbial flocs with different functions, achieving functional zoning. Furthermore, the PET geotextile allows for a certain degree of "clogging" and biological... Membrane growth and the grid support plate provide mechanical strength, ensuring the durability and stability of the PET geotextile during long-term operation, thus enhancing the reliability and service life of the reactor. The three-phase separator located at the top of the reactor body achieves efficient separation of gas, liquid, and sludge phases, collecting and discharging gas, allowing sludge to settle back into the biological reaction zone, and the supernatant to enter the sedimentation zone, improving solid-liquid separation efficiency and effluent quality while reducing the burden of subsequent treatment. Simultaneously, the effluent assembly smoothly and evenly collects and discharges the supernatant from the top of the reactor, preventing disturbance to the sludge layer in the sedimentation zone below, ensuring low suspended solids concentration and stable water quality in the effluent. The gas collection assembly enables the orderly collection and efficient export of gas separated by the three-phase separator at the top of the reactor, achieving centralized and safe treatment of waste gas and ensuring the stability of the reactor's internal environment. Furthermore, by controlling the upward flow velocity and residence time in the sedimentation and effluent zones, residual sludge is further separated, ensuring low suspended solids concentration and stable water quality in the effluent, and achieving smooth discharge of treated water.

[0012] Furthermore, the aeration system includes an aerator, the air inlet of which is connected to an air inlet via an air inlet pipe. The air inlet is located on one side of the bottom of the reactor body and is connected to a gas supply device. An air inlet regulating valve is installed on the air inlet pipe.

[0013] The beneficial effects of adopting the above technical solution are as follows: the aeration system supplies oxygen to the reactor through aerators, ensuring a sufficient oxygen supply for microorganisms. The air inlet of the aerator is connected to the air inlet through an air inlet pipe, and an air inlet regulating valve is installed on the air inlet to achieve precise control of the aeration volume. This not only improves oxygen transfer efficiency and reduces energy consumption, but also, through the coordinated work of the aeration system and the water distribution system, a suitable hydraulic shear force can be formed, which is conducive to the formation and long-term stability of aerobic granular sludge, preventing the disintegration or excessive growth of granular sludge and the resulting blockage, thus ensuring the efficient and stable operation of the reactor.

[0014] Furthermore, the water distribution system includes a main water distribution pipe, the water inlet of which is connected to the water inlet via a water inlet pipe, the water inlet being located on one side of the bottom of the reactor body, and a water inlet regulating valve being installed on the water inlet pipe; a number of first water distribution branch pipes and a number of second water distribution branch pipes are provided at intervals on the main water distribution pipe, and water distribution holes are provided at the water outlets of the number of first water distribution branch pipes and second water distribution branch pipes.

[0015] The beneficial effects of adopting the above technical solution are as follows: The water distribution system forms a high-resistance water distribution network through the main water distribution pipe, the first water distribution branch pipes and the second water distribution branch pipes arranged at intervals and with alternating lengths. The water inlet regulating valve is installed on the inlet pipe to achieve effective control of the inlet flow rate and distribution, ensuring that the sewage can rise evenly across the entire bottom cross section of the reactor. This lays the foundation for the formation of a stable upward flow and uniform hydraulic shear force in the reactor. Furthermore, through the synergistic use with the aeration system, it promotes the formation, stabilization and functional maintenance of aerobic granular sludge, and prevents sludge deposition at the bottom of the reactor and blockage of the water distribution system, ensuring the long-term stable operation of the reactor and improving treatment efficiency.

[0016] Furthermore, the diameter of the water distribution holes is 15–25 mm.

[0017] The beneficial effects of adopting the above technical solution are as follows: by setting the size of the water distribution hole to 15-25mm, it can ensure that the sewage maintains a sufficient flow velocity when passing through the hole, thereby forming a jet with high resistance, effectively preventing the attachment and blockage of suspended solids at the water distribution hole. At the same time, it can form strong and uniform hydraulic turbulence at the bottom of the reactor, providing hydraulic shear force for the formation and maintenance of aerobic granular sludge, ensuring the uniformity of water distribution and the stability of the system.

[0018] Furthermore, the side of the grid support plate away from the PET geotextile is provided with steel support.

[0019] The beneficial effects of adopting the above technical solution are as follows: When the reactor span is large, steel supports can be set on the side of the grid support plate away from the PET geotextile, which enhances the structural rigidity and deformation resistance of the entire partition component. It can effectively withstand the continuous static load and dynamic load during operation of the sludge, biofilm and water above it, and prevent the grid support plate from bending or being damaged due to long-term load. This ensures that the PET geotextile is always in a stable working position and shape, maintains the effectiveness of the internal partitioning of the reactor, the unobstructed water flow channel, and the structural safety and reliability of long-term operation.

[0020] Furthermore, the water outlet assembly includes a water outlet weir, the water outlet end of which is connected to a water outlet located on one side of the top of the reactor body.

[0021] The beneficial effects of adopting the above technical solution are as follows: the effluent component can collect and discharge the supernatant at the top of the reactor in a stable and uniform manner through the effluent weir, effectively preventing disturbance to the sludge layer in the sedimentation zone below, avoiding the resuspension of settled sludge, ensuring that the concentration of suspended solids (SS) in the effluent is maintained at a low level, thereby ensuring the final effluent quality.

[0022] Furthermore, the gas collection assembly includes several gas collection branch pipes, the inlet ends of which are connected to the outlet ends of the three-phase separator, the outlet ends of which are connected to the inlet ends of the gas collection main pipe, and the outlet ends of the gas collection main pipe are connected to the exhaust gas purification device.

[0023] The beneficial effects of adopting the above technical solution are as follows: the gas collection component gathers the gas into the gas collection main pipe through the gas collection branch pipe, realizing the orderly collection and efficient export of the gas separated by the three-phase separator at the top of the reactor. The gas collection main pipe promotes gas-liquid separation and finally delivers the collected gas smoothly to the subsequent waste gas purification device, ensuring the stability of the gas-liquid separation interface inside the reactor, ensuring the treatment effect of the three-phase separator, and realizing the centralized and safe treatment of the generated waste gas.

[0024] Furthermore, it also includes a reflux assembly, which includes a reflux outlet located at the top of the reactor body. The reflux outlet is connected to the outlet of the three-phase separator. The reflux outlet is connected to the reflux inlet via a reflux pipe. The reflux inlet is located at the bottom of the reactor body.

[0025] The beneficial effects of adopting the above technical solution are as follows: the reflux component refluxes part of the nitrified liquid (rich in nitrates) after three-phase separation at the top of the reactor to the bottom of the reactor, which is conducive to the denitrification process. It not only enhances the circulation and mixing of water in the reactor, but also improves the denitrification efficiency, especially the removal effect of total nitrogen.

[0026] Furthermore, it also includes a dosing port, which is located between the three-phase separator and the separation component, for adding aluminum salt or iron salt coagulant to the first reaction functional zone.

[0027] The beneficial effects of adopting the above technical solution are as follows: the dosing port is set between the three-phase separator and the separation component, which can accurately add aluminum salt or iron salt coagulant to the first reaction functional zone, so that the coagulant can be fully mixed and reacted with the sewage in the first reaction functional zone. The aluminum salt or iron salt coagulant can effectively adsorb phosphorus and suspended solids (SS) in the sewage, while promoting the destabilization and coagulation of colloidal organic matter (COD component). The formed flocs are precipitated to achieve efficient separation, thereby significantly enhancing the removal effect of the reactor on phosphorus, SS and COD, further improving the effluent quality, effectively solving the membrane fouling problem caused by the existing membrane bioreactors that need to achieve solid-liquid separation through membrane separation, and without the need for additional floor space.

[0028] In summary, the oxygen gradient self-coupled granular sludge partitioned reactor provided by this invention has the following beneficial effects:

[0029] (1) This oxygen gradient self-coupled granular sludge zone reactor integrates the aeration zone, water distribution zone, biological reaction zone, three-phase separation zone, sedimentation zone, and effluent zone into one unit through a vertically arranged tower structure. The compact structure significantly reduces the floor space required, simplifies the structure, and improves space utilization. Furthermore, by utilizing the oxygen gradient self-coupling mechanism within the aerobic granular sludge, nitrification and denitrification reactions can be completed simultaneously within a single reactor, eliminating the need for traditional nitrification liquid recirculation and sludge recirculation systems, thus significantly reducing energy consumption and operating costs. At the same time, it eliminates the need for expensive membrane modules, fundamentally avoiding membrane fouling, high maintenance costs, and membrane cleaning energy consumption problems.

[0030] (2) The aeration system in the reactor is located at the bottom of the reactor body. It supplies oxygen to the biological reaction zone through aerators, ensuring sufficient oxygen supply for microorganisms. The air inlet of the aerator is connected to the air inlet through an air inlet pipe. An air inlet regulating valve is installed on the air inlet to achieve precise control of the aeration volume. This not only improves oxygen transfer efficiency and reduces energy consumption, but also allows the aeration system and the water distribution system to work together to form a suitable hydraulic shear force, which is conducive to the formation and long-term stability of aerobic granular sludge. This prevents the disintegration of granular sludge or blockage caused by excessive growth, and ensures the efficient and stable operation of the reactor.

[0031] (3) The water distribution system in the reactor adopts a high-resistance water distribution network. Through the first and second water distribution branches with alternating lengths, the sewage rises uniformly on the bottom cross section of the reactor, forming a stable upward flow and uniform hydraulic shear force, preventing local short-flow or sludge deposition, and providing ideal hydraulic conditions for the uniform growth and structure maintenance of aerobic granular sludge, thereby improving the system's treatment efficiency and stability.

[0032] (4) The separation components in the reactor realize the functional zoning of the bioreactor zone through PET geotextile and grid support plate, allowing water and small molecules to pass through. The "dynamic filter cake layer" formed on the surface of PET geotextile can effectively trap microbial flocs with different functions, so that the dominant bacteria in different reaction zones are enriched and functional zoning is realized. PET geotextile allows a certain degree of "blockage" and biofilm growth. In addition, the grid support plate provides mechanical strength, ensuring the durability and stability of PET geotextile in long-term operation, maintaining the effectiveness of the internal zoning of the reactor and the unobstructed water flow channel, and enhancing the reliability and service life of the system.

[0033] (5) The three-phase separator in the reactor is set at the top of the reactor to achieve efficient separation of gas, liquid and sludge phases, collect and discharge gas, allow sludge to settle back to the biological reaction zone, and allow the supernatant to enter the sedimentation zone. This improves the solid-liquid separation efficiency and effluent quality, reduces the burden of subsequent treatment, and ensures the stability of the gas-liquid separation interface inside the reactor, thus optimizing the overall treatment effect.

[0034] (6) The sedimentation zone in the reactor can further separate residual sludge, ensuring low concentration of suspended solids in the effluent and stable water quality; the effluent zone uses an effluent weir to collect and discharge the supernatant in a stable and uniform manner, preventing disturbance to the sludge layer below, avoiding sludge re-suspension, and thus ensuring the consistency of the final effluent water quality.

[0035] (7) The reactor can be selectively equipped with a recovery component. The reflux component enhances the denitrification process by returning part of the nitrification liquid to the bottom of the reactor, thereby improving the nitrogen removal efficiency (especially the removal effect of total nitrogen) and promoting the circulation and mixing of water in the reactor, thus optimizing the dynamic balance of reaction conditions.

[0036] (8) The reactor can be selectively equipped with a dosing port, which is located between the three-phase separator and the separation component. It is used to accurately add aluminum salt or iron salt coagulant. Through chemical coagulation, the removal effect of suspended solids and phosphorus in sewage is enhanced, avoiding the interference of coagulant on the subsequent biological reaction zone. While improving the quality of effluent, the reactor structure is kept compact, and the solid-liquid separation problem caused by membrane separation in membrane bioreactors is solved. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of the present invention;

[0038] Figure 2 This is a partially enlarged view of the separating component in this invention;

[0039] Figure 3 This is a schematic diagram of the water distribution system in this invention;

[0040] Figure 4 This is a side view of the water distribution system in this invention;

[0041] The components include: 1. Reactor body; 11. Return outlet; 12. Return inlet; 13. Dosing port; 2. Aeration zone; 21. Aerator; 22. Air inlet pipe; 23. Air inlet; 24. Air inlet regulating valve; 3. Water distribution zone; 31. Inlet; 32. Main water distribution pipe; 33. Inlet pipe; 34. Inlet regulating valve; 35. First water distribution branch pipe; 36. Second water distribution branch pipe; 4. Biological reaction zone; 5. Three-phase separation zone; 51. Three-phase separator; 6. Sedimentation zone; 7. Effluent zone; 71. Effluent weir; 72. Effluent outlet; 8. Separation assembly; 81. First reaction functional zone; 82. Second reaction functional zone; 83. Sludge discharge port; 84. PET geotextile; 85. Grating support plate; 86. Steel support; 9. Gas collection assembly; 91. Gas collection branch pipe; 92. Gas collection main pipe; 93. Gas-liquid separator. Detailed Implementation

[0042] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0043] Example 1

[0044] like Figures 1-3As shown, the oxygen gradient self-coupled granular sludge partitioned reactor provided by the present invention includes a reactor body 1, which is a vertically arranged tower structure. Inside the reactor body 1, from bottom to top, are arranged an aeration zone 2, a water distribution zone 3, a biological reaction zone 4, a three-phase separation zone 5, a sedimentation zone 6, and an effluent zone 7. A sludge discharge port 83 is provided on one side of the reactor body 1. An aeration system is provided at the bottom of the reactor body 1, located in the aeration zone 2. A water distribution system is provided above the aeration system, located in the water distribution zone 3. The biological reaction zone 4 is provided with a partition component 8, with at least one layer of partition components 8, and the partition components 8 are horizontally arranged. The reactor body 1 is placed inside the reactor body 1, dividing the inner cavity of the reactor body 1 into a first reaction functional zone 81 and a second reaction functional zone 82 connected in series. The separation component 8 includes a PET geotextile 84, and grid support plates 85 are provided on the upper and lower sides of the PET geotextile 84. A three-phase separator 51 is provided at the top of the reactor body 1. The three-phase separator 51 is located in the three-phase separation zone 5 and above the separation component 8. The sedimentation zone 6 is located above the three-phase separator 51. The water outlet of the three-phase separator 51 is connected to the water outlet component, which is located in the water outlet zone 7. The gas outlet of the three-phase separator 51 is connected to the gas collection component 9.

[0045] This reactor integrates the aeration zone 2, water distribution zone 3, biological reaction zone 4, three-phase separation zone 5, sedimentation zone 6, and effluent zone 7 into a single vertically arranged tower structure. This achieves high efficiency, energy saving, and a compact layout in the wastewater treatment process, significantly reducing the footprint, simplifying the structure, and improving space utilization. Furthermore, by utilizing the self-coupling mechanism of the oxygen gradient within the aerobic granular sludge, nitrification and denitrification reactions are completed simultaneously within a single reactor, eliminating the need for traditional nitrification liquid recirculation and sludge recirculation systems, thus significantly reducing energy consumption and operating costs. Simultaneously, it eliminates the need for expensive membrane modules, fundamentally avoiding membrane fouling, high maintenance costs, and energy consumption associated with membrane cleaning. Specifically, the aeration system supplies oxygen to the biological reaction zone 4, ensuring a sufficient oxygen supply for the microorganisms. This not only improves oxygen transfer efficiency and reduces energy consumption, but also, the aeration system works in conjunction with the water distribution system to create suitable hydraulic shear force, which is conducive to the formation and long-term stability of aerobic granular sludge. This prevents clogging caused by the disintegration or excessive growth of granular sludge, ensuring the efficient and stable operation of the reactor. The water distribution system can form a high-resistance water distribution structure, ensuring that the wastewater rises uniformly across the bottom cross-section of the reactor, laying the foundation for a stable upward flow and uniform hydraulic shear force within the reactor. The partition component 8 in the biological reaction zone 4 contains at least one layer of PET geotextile 84. The PET geotextile 84 is a long-filament geotextile with a strength of not less than 50~100kN / m. 2The thickness of the grid support plate is 30-50mm, and the PET geotextile 84 is equipped with grid support plates 85 on both the upper and lower sides, dividing the reactor cavity into a first reaction functional zone 81 and a second reaction functional zone 82 connected in series. The PET geotextile 84 allows water and small molecules to pass through, and the "dynamic filter cake layer" formed on the surface of the PET geotextile can effectively trap microbial flocs with different functions, enriching the dominant bacterial species in different reaction zones and realizing functional zoning; the PET geotextile allows a certain degree of "clogging" and biofilm growth; while the grid support plate 85 provides mechanical strength, ensuring the durability and stability of the PET geotextile 84 in long-term operation, enhancing the reliability and service life of the reactor; and the three-phase separator 51 set at the top of the reactor body 1 realizes efficient separation of gas, liquid and sludge phases, can collect and discharge gas, and allow sludge to settle. The supernatant returns to the biological reaction zone 4 and enters the sedimentation zone 6, improving solid-liquid separation efficiency and effluent quality, reducing the burden of subsequent treatment, and ensuring the stability of the gas-liquid separation interface inside the reactor. Simultaneously, the effluent assembly can smoothly and evenly collect and discharge the supernatant from the bottom of the reactor, preventing disturbance to the sludge layer in the sedimentation zone 6 below, ensuring low suspended solids concentration and stable water quality in the effluent. The gas collection assembly 9 can achieve orderly collection and efficient export of the gas separated by the three-phase separator 51 at the top of the reactor, realizing centralized and safe treatment of waste gas and ensuring the stability of the internal environment of the reactor. Furthermore, the upward flow velocity in the sedimentation zone 6 is 0.5~0.8 m / h. By controlling the upward flow velocity or residence time in the sedimentation zone 6 and the effluent zone 7, residual sludge can be further separated, ensuring low suspended solids concentration and stable water quality in the effluent, and achieving smooth discharge of treated water.

[0046] like Figure 1 As shown, the aeration system includes an aerator 21. The air inlet of the aerator 21 is connected to the air inlet 23 via an air inlet pipe 22. The air inlet 23 is located on one side of the bottom of the reactor body 1 and is connected to a gas supply device. An air inlet regulating valve 24 is installed on the air inlet pipe 22. The aeration system supplies oxygen to the reactor through the aerator 21, ensuring a sufficient oxygen supply for the microorganisms. The air inlet of the aerator 21 is connected to the air inlet 23 via the air inlet pipe 22, and the air inlet 23 is equipped with an air inlet regulating valve 24, which enables precise control of the aeration rate. This not only improves oxygen transfer efficiency and reduces energy consumption, but also, through the coordinated operation of the aeration system and the water distribution system, forms a suitable hydraulic shear force, which is conducive to the formation and long-term stability of aerobic granular sludge, preventing clogging caused by the disintegration or excessive growth of granular sludge, and ensuring the efficient and stable operation of the reactor.

[0047] like Figure 1 , Figure 3 and Figure 4As shown, the water distribution system includes a main water distribution pipe 32. The inlet end of the main water distribution pipe 32 is connected to the inlet 31 via an inlet pipe 33. The inlet 31 is located on one side of the bottom end of the reactor body 1. An inlet regulating valve 34 is installed on the inlet pipe 33. Several first water distribution branch pipes 35 and several second water distribution branch pipes 36 are spaced apart on the main water distribution pipe 32. The outlet ends of the first water distribution branch pipes 35 and the second water distribution branch pipes 36 are all provided with water distribution holes with a diameter of 15-25mm. The flow velocity at the orifice of the water distribution hole should be greater than 2m / s, and the water distribution area at each point should not exceed 2m². 2 This ensures the formation of a high-resistance jet, prevents clogging, and provides suitable hydraulic shear force for aerobic granular sludge. The water distribution system is connected to the inlet 31 at the bottom of the reactor via the main water distribution pipe 32, and the water inflow is controlled by the inlet regulating valve 34. At the same time, the first and second water distribution branch pipes 35 and 36, which are of different lengths, achieve uniform distribution and efficient mixing of wastewater in the reactor, avoiding the problem of excessively high or low local loads. This not only improves the reaction efficiency but also reduces the footprint by optimizing the water flow path.

[0048] like Figure 1 and Figure 2 As shown, the preferred type of grid support plate 85 is a fiberglass grid support plate with a thickness of 30-50mm, and a steel support 86 is provided on the side of the grid support plate 85 away from the PET geotextile 84. The steel support 86 is bolted to the grid support plate 85 and the PET geotextile 84. When the reactor span is large, the steel support 86 can be provided on the side of the grid support plate 85 away from the PET geotextile 84, which enhances the structural rigidity and deformation resistance of the entire partition component 8. It can effectively withstand the continuous static load and dynamic load during operation of the sludge, biofilm and water above it, preventing the grid support plate 85 from bending or being damaged due to long-term load. This ensures that the PET geotextile 84 is always in a stable working position and shape, maintaining the effectiveness of the internal partitioning of the reactor, the unobstructed water flow channel, and the structural safety and reliability of long-term operation.

[0049] like Figure 1 As shown, the effluent assembly includes an effluent weir 71, the outlet end of which is connected to an outlet 72, which is located on one side of the top of the reactor body 1. Through the effluent weir 71, the effluent assembly can collect and discharge the supernatant at the top of the reactor in a stable and uniform manner, effectively preventing disturbance to the sludge layer in the sedimentation zone 6 below, avoiding resuspension of the settled sludge, and ensuring that the suspended solids (SS) concentration in the effluent remains at a low level, thereby ensuring the final effluent quality. The upward flow velocity in the sedimentation zone 6 is 0.5~0.8 m / h, and the upward flow time is not less than 1.5h.

[0050] like Figure 1As shown, the gas collection assembly 9 includes several gas collection branch pipes 91. The inlet end of the gas collection branch pipes 91 is connected to the outlet end of the three-phase separator 51, and the outlet end of the gas collection branch pipes 91 is connected to the inlet end of the gas collection main pipe 92. The outlet end of the gas collection main pipe 92 is connected to the waste gas purification device. A gas-liquid separator 93 is installed on the gas collection main pipe 92 to further separate the gas and liquid, ensure the stability of gas transportation and the safety of subsequent treatment devices, and the gas velocity of the gas collection branch pipes 91 is not higher than 1.5 m / s, and the gas collection main pipe 92 is not lower than the outlet water level by 0.5 to 1.0 m. The gas collection assembly 9 collects the gas through the gas collection branch pipe 91 and the gas collection main pipe 92, realizing the orderly collection and efficient export of the gas separated by the three-phase separator 51 at the top of the reactor. The gas collection main pipe 92 promotes gas-liquid separation and finally delivers the collected gas smoothly to the subsequent waste gas purification device, ensuring the stability of the gas-liquid separation interface inside the reactor, ensuring the treatment effect of the three-phase separator 51, and realizing the centralized and safe treatment of the generated waste gas.

[0051] The working principle of the oxygen gradient self-coupled granular sludge partitioned reactor provided by this invention is as follows:

[0052] This reactor achieves efficient wastewater treatment by creating an oxygen gradient within a vertical tower reactor and utilizing PET geotextile 84 to achieve microbial zoning and enrichment. First, wastewater enters through inlet 31 at the bottom of the reactor body 1, rapidly mixing with pre-added activated sludge. Simultaneously, the gas supply device is activated, and oxygen generated by the gas supply device enters the reactor through inlet 23 and aerator 21, acting as a stirrer to ensure more uniform mixing of wastewater and sludge. The bubbles generated by aerator 21, along with the water distribution system, propel the mixed liquor upwards and provide hydraulic shear force, facilitating the formation of aerobic granular sludge. During the upward movement, as oxygen diffuses upwards from the bottom aerator 21 and is consumed by microorganisms, an oxygen gradient gradually decreases from bottom to top within the reactor. The highest oxygen concentration is near the bottom aeration zone 2. As the mixed liquor rises and microorganisms consume and utilize oxygen, the oxygen concentration gradually decreases along the reactor's height, creating a suitable living environment for microorganisms with different oxygen requirements. Subsequently, the mixture passes through multiple functional bioreactor zones 4 separated by PET geotextile 84. PET geotextile 84 is a type of geotextile that is both permeable to water and can trap bacterial flocs. PET geotextile 84 allows water and small molecules to pass through freely, but traps larger bacterial flocs, thus achieving preliminary spatial optimization and separation of microbial communities with different functions. Meanwhile, PET geotextile 84 can trap and enrich microorganisms, forming dense aerobic granular sludge under suitable hydraulic shear force. Inside the aerobic granular sludge, as oxygen diffuses from the external liquid into the main granules, it is consumed layer by layer by the surface microorganisms, causing the dissolved oxygen concentration to decrease from the outside to the inside. This creates a microenvironment within a single granule that is aerobic on the outside and anoxic or anaerobic on the inside. This allows nitrification (which requires oxygen) to mainly concentrate on the outer layer of the granules, while denitrification (which requires anaerobic or anoxic conditions) can take place inside the granules. Through the oxygen gradient change formed inside the reactor, which gradually decreases in dissolved oxygen concentration from bottom to top, simultaneous nitrification and denitrification are achieved. Thus, the denitrification process can be completed without building separate anaerobic, anoxic, and aerobic tanks in the reactor, or relying on an internal reflux system for the nitrified liquid. Finally, the treated mixture rises to the top three-phase separator 51 to achieve efficient separation of gas, liquid and solid phases. That is, the waste gas is collected and discharged, the settled granular sludge is further separated in the sedimentation zone 6 and falls back to the biological reaction zone 4, and the supernatant is discharged as treated effluent that meets the standards.

[0053] Example 2

[0054] like Figure 1As shown, this embodiment, based on Embodiment 1, further includes a reflux assembly. The reflux assembly includes a reflux outlet 11, which is located on one side of the top of the reactor body 1. The reflux outlet 11 is connected to the outlet of the three-phase separator 51. The reflux outlet 11 is connected to a reflux inlet 12 via a reflux pipe, which is located on one side of the bottom of the reactor body 1. The reflux assembly can be used selectively. When needed, the reflux pipe is connected to a reflux pump, and the reflux pump is turned on. This allows a portion of the nitrified liquid (rich in nitrates) after three-phase separation at the top of the reactor to be refluxed to the bottom of the reactor. This facilitates the denitrification process, enhances the circulation and mixing of water within the reactor, and improves the nitrogen removal efficiency, especially the removal of total nitrogen.

[0055] Example 3

[0056] like Figure 1 As shown, this embodiment, based on embodiment 1 or embodiment 2, also includes a dosing port 13. The dosing port 13 is located between the three-phase separator 51 and the separation component 8, and can accurately add aluminum salt or iron salt coagulant to the first reaction functional zone 81, so that the coagulant can fully mix and react with the sewage in the first reaction functional zone 81. The aluminum salt or iron salt coagulant can effectively adsorb phosphorus and suspended solids (SS) in the sewage, and at the same time promote the destabilization and coagulation of colloidal organic matter (COD component). The formed flocs are precipitated to achieve efficient separation, thereby significantly enhancing the removal effect of the reactor on phosphorus, SS and COD, further improving the effluent quality, effectively solving the membrane fouling problem caused by the existing membrane bioreactors that need to achieve solid-liquid separation through membrane separation, and without the need for additional floor space.

Claims

1. An oxygen gradient self-coupled granular sludge partitioned reactor, characterized in that: The reactor body (1) is a vertically arranged tower structure. The reactor body (1) has an aeration zone (2), a water distribution zone (3), a biological reaction zone (4), a three-phase separation zone (5), a sedimentation zone (6), and an effluent zone (7) arranged from bottom to top inside the reactor body (1). A sludge discharge port (83) is provided on one side of the reactor body (1). An aeration system is provided at the bottom of the reactor body (1), the aeration system is located in the aeration zone (2), and a water distribution system is provided above the aeration system, the water distribution system is located in the water distribution zone (3). The water distribution system includes a main water distribution pipe (32), the water inlet of the main water distribution pipe (32) is connected to the water inlet (31) through the water inlet pipe (33), the water inlet (31) is located on one side of the bottom end of the reactor body (1), and the water inlet pipe (33) is provided with a water inlet regulating valve (34); a plurality of first water distribution branch pipes (35) and a plurality of second water distribution branch pipes (36) are provided at intervals on the main water distribution pipe (32), and the water outlets of the plurality of first water distribution branch pipes (35) and second water distribution branch pipes (36) are all provided with water distribution holes; The bioreactor zone (4) is provided with a partition component (8), which has at least one layer. The partition component (8) is horizontally arranged inside the reactor body (1) to divide the inner cavity of the reactor body (1) into a first reaction functional zone (81) and a second reaction functional zone (82) connected in series. The partition component (8) includes a PET geotextile (84), and grid support plates (85) are provided on the upper and lower sides of the PET geotextile (84). A three-phase separator (51) is provided at the top of the reactor body (1). The three-phase separator (51) is located in the three-phase separation zone (5) and above the separation component (8). The sedimentation zone (6) is located above the three-phase separator (51). The water outlet of the three-phase separator (51) is connected to the water outlet component, which is located in the water outlet zone (7). The gas outlet of the three-phase separator (51) is connected to the gas collection component (9).

2. The oxygen gradient self-coupled granular sludge partitioned reactor according to claim 1, characterized in that: The aeration system includes an aerator (21), the air inlet of the aerator (21) is connected to the air inlet (23) through the air inlet pipe (22), the air inlet (23) is located on one side of the bottom of the reactor body (1), the air inlet (23) is connected to the gas supply device, and the air inlet pipe (22) is equipped with an air inlet regulating valve (24).

3. The oxygen gradient self-coupled granular sludge partitioned reactor according to claim 1, characterized in that: The diameter of the water distribution holes is 15-25 mm.

4. The oxygen gradient self-coupled granular sludge partitioned reactor according to claim 1, characterized in that: The grid support plate (85) is provided with a steel support (86) on the side away from the PET geotextile (84).

5. The oxygen gradient self-coupled granular sludge partitioned reactor according to claim 1, characterized in that: The water outlet assembly includes a water outlet weir (71), the water outlet end of which is connected to a water outlet (72), and the water outlet (72) is located on one side of the top of the reactor body (1).

6. The oxygen gradient self-coupled granular sludge partitioned reactor according to claim 1, characterized in that: The gas collection assembly (9) includes several gas collection branch pipes (91), the inlet end of several gas collection branch pipes (91) is connected to the outlet end of the three-phase separator (51), the outlet end of several gas collection branch pipes (91) is connected to the inlet end of the gas collection main pipe (92), and the outlet end of the gas collection main pipe (92) is connected to the waste gas purification device.

7. The oxygen gradient self-coupled granular sludge partitioned reactor according to claim 1, characterized in that: It also includes a reflux assembly, which includes a reflux outlet (11) located on one side of the top of the reactor body (1). The reflux outlet (11) is connected to the outlet of the three-phase separator (51). The reflux outlet (11) is connected to the reflux inlet (12) through a reflux pipe. The reflux inlet (12) is located on one side of the bottom of the reactor body (1).

8. The oxygen gradient self-coupled granular sludge partitioned reactor according to claim 1, characterized in that: It also includes a dosing port (13), which is located between the three-phase separator (51) and the separation component (8) for adding aluminum salt or iron salt coagulant to the first reaction functional zone (81).

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