Biodopp biochemical reaction system and wastewater treatment method
Patent Information
- Application Number
- AE202602999
- Authority / Receiving Office
- AE · AE
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-06-21
- Filing Date
- 2024-08-19
Smart Images
Figure ABST_ABST
Abstract
Description
Full specification BIODOPP BIOCHEMICAL REACTION SYSTEM AND WASTEWATER TREATMENT METHODCROSS-REFERENCE TO RELATED APPLICATIONSThe present application claims priority to the Chinese Patent Application No. 202410806634X, filed on June 21, 2024, entitled “Biodopp Biochemical Reaction System and Wastewater Treatment Method”, and the entire disclosure of which is incorporated herein by reference.TECHNICAL FIELDThe present application relates to the technical field of wastewater treatment, and in particular to a BioDopp biochemical reaction system and a wastewater treatment method.BACKGROUNDCompared to conventional biochemical reactors, BioDopp biochemical reactors offer advantages such as saving space, operating continuously and efficiently, increasing the ratio of simultaneous nitrification and denitrification reactions, and short-cut nitrification and denitrification reactions, thereby saving operating costs and simplifying operation.In existing BioDopp biochemical reactors, two technical solutions are usually adopted to return the sludge separated by sedimentation in the sludge and water separation zone to a biochemical tank. One technical solution adopts a method of pure hydraulic entrainment, that is, an average hydraulic flow velocity of 0.3 m / s or more is reached in the bottom channel of the sludge and water separation zone by means of airlift return, so that the settled sludge is entrained back to the biochemical tank. The other technical solution adopts a sludge suction machine, a sludge scraper, or a sludge suction-scraping machine to mechanically transport the sludge directionally back to a suitable location in the biochemical tank. However, in the case of pure hydraulic entrainment, once the length of the sludge and water separation zone exceeds a certain limit, it will affect the entrainment capacity, severely impact the sedimentation effect, and thus affect the entire biochemical system. In the case of pure mechanical transport, on the one hand, it will increase equipment investment, and on the other hand, since the main working elements of the sludge suction machine, the sludge scraper, or the sludge suction-scraping machine operate in a submerged working mode, once a mechanical failure occurs, maintenance will be relatively troublesome, which will bring inconvenience to actual operation.Therefore, there is an urgent need for a BioDopp biochemical reaction system and a wastewater treatment method to solve the above problems.BRIEF SUMMARYAccording to the present application, there is provided a BioDopp biochemical reaction system and a wastewater treatment method to solve the defects of existing BioDopp biochemical reactors, such as unstable entrainment capacity, high energy consumption, and difficult maintenance. It achieves dual carbon utilization, effectively saving carbon source consumption for nitrogen and phosphorus removal. Moreover, it has a simple structural layout, saving floor space, reducing mechanical equipment, and effectively reducing construction and operating costs.According to an embodiment of the present application, there is provided a BioDopp biochemical reaction system, comprising an anaerobic zone, an anoxic zone, a first aerobic zone, a second aerobic zone, a three-phase separator, and a gas release and deoxygenation zone;wherein a tail end of the anaerobic zone is in communication with the anoxic zone, a tail end of the anoxic zone is in communication with the first aerobic zone, a tail end of the first aerobic zone is in communication with the second aerobic zone, a tail end of the second aerobic zone is in communication with the gas release and deoxygenation zone, and a tail end of the gas release and deoxygenation zone is in communication with the anoxic zone;wherein the three-phase separator is arranged at the top of a tail end of the second aerobic zone, and the three-phase separator comprises a gas collection unit and a water collection unit;wherein the gas collection unit comprises a main gas collection hood, an exhaust pipe, and a plurality of branch gas collection hood layers, the main gas collection hood covers the branch gas collection hood layers located at the top, a gas inlet end of the exhaust pipe is in communication with the main gas collection hood, a gas exhaust end of the exhaust pipe is in communication with the first aerobic zone, the branch gas collection hood layer comprises a plurality of branch gas collection hoods arranged at intervals, a gas collection space is formed inside the branch gas collection hood, an outer wall of the branch gas collection hood forms a sludge guide surface, the branch gas collection hoods of adjacent branch gas collection hood layers are arranged in an alternating manner, a tortuous gap is formed between the branch gas collection hoods of the plurality of branch gas collection hood layers, and the tortuous gap is in communication with the second aerobic zone; andwherein the water collection unit comprises a water collection trough and a drainage channel, the water collection trough is arranged at the top of the main gas collection hood, and the drainage channel is in communication with the water collection trough.According to an embodiment of the present application, the BioDopp biochemical reaction system further comprises a first flow passage, wherein a head end of the first flow passage is in communication with the tail end of the anoxic zone, and a tail end of the first flow passage is in communication with the first aerobic zone; andwherein the first flow passage is provided with a first return device, a head end of the first return device is in communication with the tail end of the anoxic zone, and a tail end of the first return device is in communication with the anaerobic zone.According to an embodiment of the present application, the BioDopp biochemical reaction system further comprises a second flow passage, wherein a head end of the second flow passage is in communication with the anaerobic zone, and a tail end of the second flow passage is in communication with the anoxic zone.According to an embodiment of the present application, the BioDopp biochemical reaction system further comprises a third flow passage, wherein the bottom of the third flow passage is in communication with the tail end of the second aerobic zone, the top of the third flow passage is in communication with the gas release and deoxygenation zone, and the third flow passage is provided with a airlift device;and / or, further comprising a fourth flow passage, wherein the bottom of the fourth flow passage is in communication with the tail end of the anoxic zone, the top of the fourth flow passage is in communication with the first aerobic zone, and the fourth flow passage is provided with a airlift device.According to an embodiment of the present application, the anoxic zone and / or the first aerobic zone are provided with guide walls for extending a water flow path.According to an embodiment of the present application, a horizontal inclination angle of the sludge guide surface is greater than or equal to 45°;a spacing between the adjacent branch gas collection hoods in each of the branch gas collection hood layers is greater than or equal to 80 mm;an overlap distance between the branch gas collection hoods in the adjacent branch gas collection hood layers is greater than or equal to 80 mm; anda width of the tortuous gap is greater than or equal to 80 mm.According to an embodiment of the present application, the tail end of the second aerobic zone and / or the gas release and deoxygenation zone are provided with at least one of an DO online monitoring element and an ORP online monitoring element.According to an embodiment of the present application, there is provided a wastewater treatment method based on the BioDopp biochemical reaction system as described in any of the above, comprising:introducing wastewater into the anaerobic zone, and conducting an anaerobic phosphorus release reaction after mixing carbon source in the wastewater with a denitrified sludge mixed liquor returned from the anoxic zone to the anaerobic zone, to obtain an anaerobic phosphorus release mixed liquor;introducing the anaerobic phosphorus release mixed liquor into a head end of the anoxic zone, and conducting a denitrifying nitrogen and phosphorus removal reaction and a denitrifying nitrogen and carbon removal reaction after mixing the anaerobic phosphorus release mixed liquor with a nitrified sludge mixed liquor, which has been subjected to degassing and dissolved oxygen removal in the gas release and deoxygenation zone, to obtain a denitrified sludge mixed liquor;returning a portion of the denitrified sludge mixed liquor to the anaerobic zone for circulation, and sequentially introducing another portion of the denitrified sludge mixed liquor into the first aerobic zone and the second aerobic zone to perform an aerobic phosphorus uptake reaction, an aerobic carbon removal reaction, and a nitrification reaction, to obtain a nitrified sludge mixed liquor; andintroducing the nitrified sludge mixed liquor into the three-phase separator, allowing effluent separated by gas collection and sedimentation to flow out, conveying gas to the first aerobic zone and / or the second aerobic zone for reuse, and allowing nitrified sludge separated by sedimentation to slide down along a path to the second aerobic zone, to accumulate at the tail end of the second aerobic zone, and to flow towards the gas release and deoxygenation zone, wherein a portion of the nitrified sludge is discharged at the tail end of the second aerobic zone and / or discharged from the gas release and deoxygenation zone, and another portion of the nitrified sludge mixed liquor is introduced into the head end of the anoxic zone via the gas release and deoxygenation zone for circulation.According to an embodiment of the present application, the dissolved oxygen at the tail end of the second aerobic zone is controlled to be less than or equal to 2.0 mg / L, and / or the oxidation-reduction potential at the tail end of the second aerobic zone is controlled to be less than or equal to +150.0 mV;and / or the dissolved oxygen at the tail end of the gas release and deoxygenation zone is controlled to be less than or equal to 1.0 mg / L, and / or the oxidation-reduction potential at the tail end of the gas release and deoxygenation zone is controlled to be less than or equal to +100.0 mV.According to an embodiment of the present application, a return ratio from the anoxic zone to the anaerobic zone is less than or equal to 200%, and a circulation ratio from the anoxic zone to the first aerobic zone is greater than or equal to 300%.According to an embodiment of the present application, there is provided a BioDopp biochemical reaction system. Firstly, the existing sludge and water separation zone is replaced with a three-phase separator. On the one hand, it can reduce the use of mechanical equipment such as a sludge suction machine, a sludge scraper, or a sludge suction-scraping machine, save investment, lower operating costs, reduce equipment failures, and facilitate operation and maintenance. On the other hand, the three-phase separator allows for more efficient use of the existing tank volume, as the bottom of the three-phase separator can still be used as an aerobic zone, the time for aerobic biochemical reaction is increased, which is conducive to increasing the volume of treated water or saving floor space. Secondly, a gas release and deoxygenation zone is added after the aerobic zone, which can significantly reduce the content of dissolved oxygen in the nitrified sludge mixed liquor returned to the anoxic zone. This greatly reduces the consumption of carbon source in the raw water by dissolved oxygen of the nitrified sludge mixed liquor in the anoxic zone. It not only directly saves carbon source addition and operating costs, but also directly enhances the denitrifying nitrogen removal efficiency of the reactor. At the same time, it indirectly enhances the phosphorus release efficiency in the anaerobic zone, thereby enhancing the overall nitrogen and phosphorus removal efficiency of the reactor.Compared with conventional A2O biochemical reactors, the BioDopp biochemical reaction system provided by the present application has a compact integrated tank layout. The use of a three-phase separator not only further saves floor space, but also eliminates the need for specialized sludge collection and return facilities. The separated sludge is finally entrained back to the anoxic zone by the nitrified liquor return for cyclic biochemical reaction.Other advantages, objectives, and features of the present application will be set forth to some extent in the following description, and to some extent, will be obvious to a person skilled in the art based on the investigation and study of the following content, or may be taught from the practice of the present application. The objectives and other advantages of the present application can be achieved and obtained through the following description.BRIEF DESCRIPTION OF THE DRAWINGSTo illustrate solutions of the present application or in the prior art more clearly, accompanying drawings used in the description of the embodiments or the prior art are briefly described below. Obviously, the drawings described below are only some embodiments of the present application. For a person skilled in the art, other drawings may also be obtained based on these drawings without creative effort.FIG. 1 is a schematic diagram of a BioDopp biochemical reaction system according to a first embodiment of the present application;FIG. 2 is the A-A sectional view from FIG. 1;FIG. 3 is the B-B sectional view from FIG. 1;FIG. 4 is a schematic diagram of a BioDopp biochemical reaction system according to a second embodiment of the present application;FIG. 5 is the C-C sectional view from FIG. 4;FIG. 6 is the D-D sectional view from FIG. 4;FIG. 7 is a schematic diagram of a BioDopp biochemical reaction system according to a third embodiment of the present application;FIG. 8 is the E-E sectional view from FIG. 7;FIG. 9 is the F-F sectional view from FIG. 7;FIG. 10 is a schematic diagram of a BioDopp biochemical reaction system according to a fourth embodiment of the present application;FIG. 11 is the G-G sectional view from FIG. 10;FIG. 12 is the H-H sectional view from FIG. 10;FIG. 13 is a schematic diagram of a BioDopp biochemical reaction system according to a fifth embodiment of the present application;FIG. 14 is the I-I sectional view from FIG. 10;FIG. 15 is the J-J sectional view from FIG. 10; andFIG. 16 is a schematic diagram of a wastewater treatment method based on the BioDopp biochemical reaction system according to an embodiment of the present application.Reference numerals:1. Anaerobic zone; 2. anoxic zone; 3. first aerobic zone; 4. second aerobic zone; 5. three-phase separator; 501. main gas collection hood; 502. exhaust pipe; 503. branch gas collection hood; 504. water collection trough; 505. drainage channel; 6. gas release and deoxygenation zone; 7. first flow passage; 8. second flow passage; 9. third flow passage; 10. anaerobic mixing zone; 11. first return device; 12. return pipe; 13. airlift device; 14. fourth flow passage; 15. DO online monitoring element; 16. ORP online monitoring element.SPECIFIC MODES FOR CARRYING OUT THE EMBODIMENTSTo illustrate the objectives, solutions, and advantages of the present application clearly, the solutions of the present application are described clearly and completely below in combination with the drawings in the present application. The described embodiments are part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by a person skilled in the art based on the embodiments of the present application, without any creative effort, shall fall within the scope of the present application.In the description of the embodiments of the present application, it should be noted that the orientation or positional relationships indicated by the terms such as “center”, “longitudinal”, “lateral”, “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, and “outside” are based on the orientation or positional relationship shown in the drawings, and are merely for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or component stated must have a particular orientation, or be constructed and operated in a particular orientation, and thus cannot be understood as limitation to the embodiments of the present application. Furthermore, the terms “first”, “second”, and “third” are only used for descriptive purposes and should not be construed as indicating or implying a relative importance.In the description of embodiments of the present application, it should be noted that, unless otherwise explicitly stated and defined, the terms “connected to” and “connected” shall be understood broadly. For example, it may refer to a fixed connection, a detachable connection, or an integrated connection. It may refer to a mechanical connection or an electric connection, or it may refer to a direct connection or an indirect connection through an intermediate medium. The specific meanings of the terms above in embodiments of the present application may be understood by a person skilled in the art in accordance with specific circumstances.In the embodiments of the present application, unless otherwise explicitly stated and defined, the first feature being located “on” or “under” the second feature may refer to that the first feature is in direct contact with the second feature or the first feature is in indirect contact with the second feature by an intermediate medium. In addition, the first feature being “on”, “above”, and “over” the second feature may refer to that the first feature is directly above or obliquely above the second feature, or simply refer to that the level of the first feature is higher than that of the second feature. The first feature being “under,” “below,” and “beneath” the second feature may refer to that the first feature is directly below or obliquely below the second feature, or simply refer to that the level of the first feature is lower than that of the second feature.In the description of the present specification, the description with reference to the terms “one embodiment,” “some embodiments,” “an example,” “specific example,” “some examples” and the like, refers to that specific features, structures, materials or characteristics described in combination with an embodiment or an example are included in at least one embodiment or example of the embodiments of the present application. In the present specification, the schematic expressions of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. In addition, a person skilled in the art may combine different embodiments or examples described in the description, as well as the features of different embodiments or examples, without conflicting with each other.The BioDopp biochemical reaction system and wastewater treatment method provided by the present application are described below with reference to FIG. 1 to FIG. 16.It should be noted that the term “head end” as described below specifically refers to the inflow end of wastewater, and the term “tail end” as described below specifically refers to the outflow end of wastewater. For example, “the head end of the first flow passage 7 being in communication with the tail end of the anoxic zone 2” specifically refers to that the inflow end of the first flow passage 7 is in communication with the outflow end of the anoxic zone 2.Referring to FIG. 1 to FIG. 3, there is provided a BioDopp biochemical reaction system according to an embodiment of the present application, comprising: an anaerobic zone 1, an anoxic zone 2, a first aerobic zone 3, a second aerobic zone 4, a three-phase separator 5, and a gas release and deoxygenation zone 6, wherein a tail end of the anaerobic zone 1 is in communication with the anoxic zone 2, a tail end of the anoxic zone 2 is in communication with the first aerobic zone 3, a tail end of the first aerobic zone 3 is in communication with the second aerobic zone 4, a tail end of the second aerobic zone 4 is in communication with the gas release and deoxygenation zone 6, and a tail end of the gas release and deoxygenation zone 6 is in communication with the anoxic zone 2;wherein the three-phase separator 5 is arranged at the top of a tail end of the second aerobic zone 4, and the three-phase separator 5 comprises a gas collection unit and a water collection unit;wherein the gas collection unit comprises a main gas collection hood 501, an exhaust pipe 502, and a plurality of branch gas collection hood layers, the main gas collection hood 501 covers the branch gas collection hood layers located at the top, a gas inlet end of the exhaust pipe 502 is in communication with the main gas collection hood 501, a gas exhaust end of the exhaust pipe 502 is in communication with the first aerobic zone 3, the branch gas collection hood layer comprises a plurality of branch gas collection hoods 503 arranged at intervals, a gas collection space is formed inside the branch gas collection hood 503, an outer wall of the branch gas collection hood 503 forms a sludge guide surface, the branch gas collection hoods 503 of adjacent branch gas collection hood layers are arranged in an alternating manner, a tortuous gap is formed between the branch gas collection hoods 503 of the plurality of branch gas collection hood layers, and the tortuous gap is in communication with the second aerobic zone 4; andwherein the water collection unit comprises a water collection trough 504 and a drainage channel 505, the water collection trough 504 is arranged at the top of the main gas collection hood 501, and the drainage channel 505 is in communication with the water collection trough 504.According to an embodiment of the present application, there is provided a BioDopp biochemical reaction system. Firstly, the existing sludge and water separation zone is replaced with a three-phase separator 5. On the one hand, it can reduce the use of mechanical equipment such as a sludge suction machine, a sludge scraper, or a sludge suction-scraping machine, save investment, lower operating costs, reduce equipment failures, and facilitate operation and maintenance. On the other hand, the three-phase separator 5 allows for more efficient use of the existing tank volume, as the bottom of the three-phase separator 5 can still be used as an aerobic zone, the time for aerobic biochemical reaction is increased, which facilitates a higher volume of treated water, or saves floor space. Secondly, a gas release and deoxygenation zone 6 is added after the aerobic zone, which can significantly reduce the content of dissolved oxygen in the nitrified sludge mixed liquor returned to the anoxic zone 2. This greatly reduces the consumption of carbon source in the raw water by dissolved oxygen of the nitrified sludge mixed liquor in the anoxic zone 2. It not only directly saves carbon source addition and operating costs, but also directly enhances the denitrifying nitrogen removal efficiency of the reactor. At the same time, it indirectly enhances the phosphorus release efficiency in the anaerobic zone 1, thereby strengthening the overall nitrogen and phosphorus removal efficiency of the reactor. In addition, after the division of aerobic zones (divided into the first aerobic zone 3 and the second aerobic zone 4), it is convenient to achieve different levels of aeration in different aerobic zones, which is more conducive to controlling the aerobic biochemical reaction rate and to controlling the dissolved oxygen in the nitrified return liquor at the tail end of the aerobic zones to be low, thereby further enhancing the overall removal efficiency of pollutants such as carbon, nitrogen, and phosphorus in the reactor. Compared with conventional A2O biochemical reactors, the BioDopp biochemical reaction system provided by the present application has a compact integrated tank layout. The use of a three-phase separator 5 not only further saves floor space, but also eliminates the need for specialized sludge collection and return facilities. The separated sludge is finally entrained back to the anoxic zone 2 by the nitrified liquor return for cyclic biochemical reaction.In an embodiment as shown in FIG. 1, the number of each of the anaerobic zone 1, the anoxic zone 2, the first aerobic zone 3, and the second aerobic zone 4 is one. The anaerobic zone 1, the anoxic zone 2, the first aerobic zone 3, and the second aerobic zone 4 are disposed adjacent to each other sequentially. The head end of the anaerobic zone 1 is provided with an inlet pipe for introducing wastewater into the anaerobic zone 1. A second flow passage 8 is provided between the anaerobic zone 1 and the anoxic zone 2. The head end of the second flow passage 8 is in communication with the tail end of the anaerobic zone 1, and the tail end of the second flow passage 8 is in communication with the head end of the anoxic zone 2, wherein the tail end of the anaerobic zone 1 is provided with a water passage hole to connect the anaerobic zone 1 and the second flow passage 8. A first flow passage 7 is provided between the anoxic zone 2 and the first aerobic zone 3. The head end of the first flow passage 7 is in communication with the tail end of the anoxic zone 2, and the tail end of the first flow passage 7 is in communication with the head end of the first aerobic zone 3. The tail end of the anoxic zone 2 is provided with a water passage hole to connect the anoxic zone 2 and the first flow passage 7. A third flow passage 9 is provided between the second aerobic zone 4 and the gas release and deoxygenation zone 6. The bottom of the third flow passage 9 is in communication with the end of the second aerobic zone 4, and the top of the third flow passage 9 is in communication with the gas release and deoxygenation zone 6.Referring to FIGS. 2, 5, 8, 11, and 14, the gas collection unit comprises a main gas collection hood 501, an exhaust pipe 502, and two branch gas collection hood layers. Each of the branch gas collection hood layers comprises a plurality of branch gas collection hoods 503 arranged horizontally at intervals. The cross-section of the branch gas collection hood 503 is an inverted “V” shape, a gas collection space is formed inside the branch gas collection hood 503, and two outer side walls of the branch gas collection hood 503 form sludge guide surfaces. In the three-phase separator 5, the gas generated by the reaction is disposed in the gas collection space, and moves upward through the gaps between adjacent branch gas collection hoods 503 and converges into the main gas collection hood 501. Finally, it is discharged into the first aerobic zone 3 through the exhaust pipe 502. The sludge moves downward under the collection and guidance of the sludge guide surface and reaches the tail end of the second aerobic zone 4 under the driving effect of the water flow. The water collection unit comprises a plurality of water collection troughs 504 and a drainage channel 505. The drainage channel 505 is arranged along the arrangement direction of a plurality of branch gas collection hoods 503, and its tail end is in communication with a drainage pipe. The plurality of water collection troughs 504 are arranged along the direction of the drainage channel 505 at intervals, to collect water from different locations into the drainage channel 505 and finally discharged through the drainage pipe.The head end of the anaerobic zone 1 is provided with an anaerobic mixing zone 10. Both the anaerobic mixing zone 10 and the gas release and deoxygenation zone 6 are provided with stirring and mixing devices (such as a submersible mixer or an anaerobic agitator). The stirring and mixing devices can promote sufficient contact between wastewater and microorganisms. Through stirring and mixing, the distribution of organic matter in wastewater can be enhanced, or the organic matter in wastewater can be adsorbed onto microbial flocs, promoting the contact between microorganisms and wastewater, and increasing wastewater treatment efficiency. Stirring and mixing can prevent settling of wastewater and sludge in the anaerobic zone 1 and the gas release and deoxygenation zone 6 to maintain the homogeneity of the reaction system, thereby promoting the growth and metabolism of microorganisms. Furthermore, the stirring and mixing devices can effectively prevent sludge deposition within the reactor.Referring to FIG. 1, according to some embodiments of the present application, a first return device 11 is provided in the first flow passage 7. The head end of the first return device 11 is in communication with the tail end of the anoxic zone 2, and the tail end of the first return device 11 is in communication with the anaerobic zone 1. Due to a large number of nitrate nitrogen electron acceptors carried in the sludge return of the anaerobic zone 1 of the classic A2O bioreactor, some high-quality carbon sources (Volatile Fatty Acids (VFAs)) in the wastewater will be wasted from a biochemical perspective, the carbon sources are directly used for denitrification, thereby affecting the anaerobic phosphorus release reaction process and thus impacting the entire biological phosphorus removal process. However, the BioDopp biochemical reaction system provided by the present application can return the mixed liquor after denitrification to the anaerobic zone 1 for a cyclic anaerobic phosphorus release reaction, which can minimize this impact. Although the UCT process can reduce this impact, it requires three sets of return facilities: one set of sludge return facility and two sets of mixed liquor return facilities, that is, the sludge returns to the anoxic zone 2, the nitrified liquor from the aerobic tank returns to the anoxic zone 2, and the denitrified liquor from the anoxic zone 2 returns to the anaerobic zone 1. The solution of the present application essentially combines sludge return and nitrified liquor return into one, which not only saves one set of return facility, but more importantly, reduces one control point, making the operation simpler and convenient for operation and maintenance management.In an embodiment, the first return device 11 is a submersible axial flow pump or an anaerobic airlift device, and the first return device 11 is in communication with a return pipe 12 that is in communication with the head end of the anaerobic zone 1. The submersible axial flow pump is characterized by high efficiency, compact structure, strong adaptability, and high reliability. It can provide high flow rate and low head, suitable for the requirements of high flow rate and low head pumping. At the same time, because it is entirely submerged in water, the structure is compact, the floor space is small, and it is installed in water, so it is less affected by external factors, and the operation is stable and reliable.Referring to FIGS. 1 and 2, according to some embodiments of the present application, the bottom of the third flow passage 9 is in communication with the tail end of the second aerobic zone 4, and the top of the third flow passage 9 is in communication with the gas release and deoxygenation zone 6. A airlift device 13 is provided within the third flow passage 9. By providing the airlift device 13 within the third flow passage 9, the return energy consumption is greatly reduced, and the return flow rate can be increased within an acceptable energy consumption range. This not only enhances the denitrification efficiency but also increases the sludge concentration in the reactor, increases the volumetric loading, reduces the tank volume, and further saves floor space.Referring to FIGS. 4, 7, 10, and 13, according to some embodiments of the present application, the BioDopp biochemical reaction system further comprises a fourth flow passage 14. The bottom of the fourth flow passage 14 is in communication with the tail end of the anoxic zone 2, and the top of the fourth flow passage 14 is in communication with the first aerobic zone 3. A airlift device 13 is provided inside the fourth flow passage 14.In an embodiment, the fourth flow passage 14 is arranged adjacent to the first flow passage 7, and the bottom of the fourth flow passage 14 is in communication with the tail end of the anoxic zone 2 through the first flow passage 7.It should be noted that, in specific embodiments, the airlift device 13 can be provided inside the third flow passage 9, or inside the fourth flow passage 14, or inside both the third flow passage 9 and the fourth flow passage 14, depending on different working conditions.Referring to FIGS. 7, 10, and 13, according to some embodiments of the present application, the anoxic zone 2 and / or the first aerobic zone 3 are provided with guide walls for extending a water flow path. By providing guide walls for extending the water flow path in the anoxic zone 2 and / or the first aerobic zone 3, the reaction time of wastewater in the anoxic zone 2 and / or the first aerobic zone 3 can be increased, thereby improving the treatment efficiency of the wastewater treatment system. Extending the water flow path allows wastewater to remain in the anoxic zone 2 and the first aerobic zone 3 for a longer period, which is beneficial for the degradation and removal of organic matter in the wastewater by microorganisms. The provision of guide walls can effectively guide the water flow, allowing it to flow along a predetermined path, avoiding phenomena such as vortex and short circuit caused by direct channels, ensuring that the wastewater is fully mixed and in contact with microorganisms throughout the reactor, improving the wastewater treatment efficiency and removal rate, and enhancing the performance and stability of the treatment system.In some embodiments, the arrangement of the guide walls can be referred to FIG. 7. A plurality of guide walls are arranged at intervals along the transverse direction as shown in FIG. 7 inside the anoxic zone 2 and the first anaerobic zone 1. Each of the guide walls is provided with a water passage. The wastewater flows tortuously in the anoxic zone 2 and the first anaerobic zone 1, which can effectively increase its reaction time in the anoxic zone 2 and the first anaerobic zone 1.In some embodiments, the arrangement of the guide walls can be referred to FIGS. 10 and 13. Two arc-shaped guide walls are provided opposite each other in the anoxic zone 2. The two arc-shaped guide walls are provided in the transverse direction, as shown in FIGS. 10 and 13. The upper and lower sides of the guide walls arranged transversely form guide zones, respectively, to delay the wastewater reaction time in the anoxic zone 2. A plurality of guide walls are arranged at intervals along the vertical direction in the first aerobic zone 3. Each of the guide walls is provided with a water passage. The wastewater flows tortuously in the first anaerobic zone 1, which can effectively increase its reaction time in the anoxic zone 2 and the first anaerobic zone 1.It can be seen from the above embodiments that in the BioDopp biochemical reaction system provided by the present application, the guide walls in the anoxic zone 2 and the first aerobic zone 3 can be arranged according to actual needs, and are not limited to the above methods.According to some embodiments of the present application, a horizontal inclination angle of the sludge guide surface is greater than or equal to 45°. Under the premise of being able to collect and guide the sludge, the sludge collected on the sludge guide surface can fall smoothly, preventing the sludge from accumulating on the guide surface.According to some embodiments of the present application, a spacing between the adjacent branch gas collection hoods 503 in each of the branch gas collection hood layers is greater than or equal to 80 mm, an overlap distance between the branch gas collection hoods 503 in the adjacent branch gas collection hood layers is greater than or equal to 80 mm, and a width of the tortuous gap is greater than or equal to 80 mm. With the above arrangement, it is possible to prevent bubbles from escaping to the upper sedimentation and water collection unit, avoiding affecting the sedimentation effect and causing the effluent quality to deteriorate.Referring to FIGS. 1, 4, 7, 10, and 13, according to some embodiments of the present application, the tail end of the second aerobic zone 4 and the gas release and deoxygenation zone 6 are provided with an DO online monitoring element 15 and an ORP online monitoring element 16. The DO online (dissolved oxygen) monitoring element can monitor the content of dissolved oxygen in the water in real time. Dissolved oxygen is an important parameter for the survival of aquatic organisms and the wastewater treatment process. It reflects the oxygen content in the water and is crucial for the growth of organisms and the degradation of organic matter in wastewater. Therefore, the DO online monitoring element 15 can help monitor changes in dissolved oxygen in the water, providing real-time data support for the wastewater treatment process for timely regulation and management. The ORP online (oxidation-reduction potential) monitoring element can monitor the oxidation-reduction potential in the water. The oxidation-reduction potential reflects the balance between oxidizing and reducing substances in the water and is of great significance for chemical reactions and electrochemical processes in the wastewater treatment process. By monitoring the ORP value, the redox environment in the water can be understood, thereby optimizing the wastewater treatment process, controlling the redox reaction, and ensuring the normal operation of the wastewater treatment system.In some embodiments, depending on actual needs, only the tail end of the second aerobic zone 4 is provided with at least one of the DO online monitoring element 15 and the ORP online monitoring element 16, and the gas release and deoxygenation zone 6 is provided with at least one of the DO online monitoring element 15 and the ORP online monitoring element 16.Referring to FIG. 16, according to the present application, the wastewater treatment method comprises:S1, introducing wastewater into the anaerobic zone 1, and conducting an anaerobic phosphorus release reaction after mixing high-quality carbon source in the wastewater with a denitrified sludge mixed liquor returned from the anoxic zone 2 to the anaerobic zone 1, to obtain an anaerobic phosphorus release mixed liquor;S2, introducing the anaerobic phosphorus release mixed liquor into a head end of the anoxic zone 2, and conducting a denitrifying nitrogen and phosphorus removal reaction and a denitrifying nitrogen and carbon removal reaction after mixing the anaerobic phosphorus release mixed liquor with a nitrified sludge mixed liquor, which has been subjected to degassing and dissolved oxygen removal in the gas release and deoxygenation zone 6, to obtain a denitrified sludge mixed liquor;S3, returning a portion of the denitrified sludge mixed liquor to the anaerobic zone 1 for circulation, and sequentially introducing another portion of the denitrified sludge mixed liquor into the first aerobic zone 3 and the second aerobic zone 4 to perform an aerobic phosphorus uptake reaction, an aerobic carbon removal reaction, and a nitrification reaction, to obtain a nitrified sludge mixed liquor; andS4, introducing the nitrified sludge mixed liquor into the three-phase separator 5, allowing effluent separated by gas collection and sedimentation to flow out, conveying gas to the first aerobic zone 3 and / or the second aerobic zone 4 for reuse, and allowing nitrified sludge separated by sedimentation to slide down along a path to the second aerobic zone 4, to accumulate at the tail end of the second aerobic zone 4, and to flow towards the gas release and deoxygenation zone 6, wherein a portion of the nitrified sludge is discharged at the tail end of the second aerobic zone and / or discharged from the gas release and deoxygenation zone 6, and another portion of the nitrified sludge mixed liquor is introduced into the head end of the anoxic zone 2 via the gas release and deoxygenation zone 6 for circulation.In an embodiment, in step S1, phosphate-accumulating organisms (PAOs) can only store high-quality carbon sources (VFAs) intracellularly in the form of PHA or PHB and complete the phosphorus release process under anaerobic conditions when there is no dissolved oxygen or electron acceptors such as nitrate nitrogen. When the wastewater is introduced into the anaerobic zone 1, the high-quality carbon sources (VFAs) in the wastewater are mixed with the denitrified sludge mixed liquor returned from the anoxic zone 2 to anaerobic zone 1. The sludge mixed liquor after denitrification can better meet the above-mentioned anaerobic phosphorus release environment, with very low dissolved oxygen and electron acceptors such as nitrate nitrogen, which can efficiently complete the biochemical reaction process of anaerobic phosphorus release and obtain the anaerobic phosphorus release mixed liquor.In step S2, when the anaerobic phosphorus release mixed liquor is introduced into the anoxic zone 2, it mixes with the nitrified sludge, which returns to the anoxic zone 2 from the gas release and deoxygenation zone 6, and is subjected to the denitrifying nitrogen and phosphorus removal reaction and the denitrifying nitrogen and carbon removal reaction. This mainly involves the conversion of nitrate nitrogen and organic waste. In the denitrifying nitrogen and phosphorus removal reaction, the PHA or PHB within the phosphate-accumulating organisms (PAOs) are used as electron donors to reduce nitrate nitrogen to nitrogen gas, and absorb an excess amount of orthophosphate simultaneously, thus achieving denitrifying nitrogen and phosphorus removal. Simultaneously, in the denitrifying nitrogen and carbon removal reaction, other remaining organic carbon sources in the wastewater are also used as electron donor to reduce nitrate nitrogen to nitrogen gas under the utilization of denitrifying bacteria, thus achieving denitrifying nitrogen and carbon removal. The wastewater after the denitrifying nitrogen and phosphorus removal reaction, as well as the denitrifying nitrogen and carbon removal reaction, is transformed into the denitrified sludge mixed liquor.In step S3, a portion of the denitrified sludge mixed liquor is introduced into the anaerobic zone 1 for repeated circulation above. Phosphate-accumulating organisms are continuously supplied to the anaerobic zone 1 to complete the anaerobic phosphorus release reaction for circulation. Another portion of the denitrified sludge mixed liquor is sequentially introduced into the first aerobic zone 3 and the second aerobic zone 4, which are subjected to an aerobic phosphorus uptake reaction, an aerobic carbon removal reaction, and a nitrification reaction, to obtain the nitrified sludge mixed liquor ultimately. Under aerobic conditions, phosphorus in the wastewater is excessively adsorbed and stored by phosphorus-accumulating organisms (PAOs) (referred to as the aerobic phosphorus uptake reaction). Simultaneously, the remaining organic waste is oxidized and decomposed, further removing carbon. During the process, nitrification also occurs, converting ammonia nitrogen into nitrate nitrogen. In step S3, after the division of aerobic zones (divided into the first aerobic zone 3 and the second aerobic zone 4), it is convenient to achieve different levels of aeration in different aerobic zones, which is more conducive to controlling the aerobic biochemical reaction rate and the low dissolved oxygen in the nitrified return liquor at the tail end of the aerobic zones, thereby further enhancing the overall removal efficiency of pollutants such as carbon, nitrogen, and phosphorus in the reactor.In step S4, after the nitrified sludge mixed liquor is treated by the three-phase separator 5, three products, including effluent, gas, and nitrified sludge, are obtained. The clearer water, separated by gas collection and sedimentation, flows out of the three-phase separator 5. The gas is conveyed to the first aerobic zone 3 and / or the second aerobic zone 4 for reuse to provide oxygen and promote the wastewater treatment reaction. The nitrified sludge separated by sedimentation slides down along a path to the second aerobic zone 4, and accumulates at the tail end of the second aerobic zone. A portion of the nitrified sludge is discharged at the tail end of the second aerobic zone 4, while another portion of the nitrified sludge flows toward the gas release and deoxygenation zone 6; or all of the nitrified sludge flows toward the gas release and deoxygenation zone 6, wherein a portion of the nitrified sludge is discharged from the gas release and deoxygenation zone 6. The nitrified sludge mixed liquor is introduced into the head end of the anoxic zone 2 via the gas release and deoxygenation zone 6 for circulation, thus maintaining the continuous denitrification reaction and ultimately achieving complete nitrogen removal.According to some embodiments of the present application, the dissolved oxygen at the tail end of the second aerobic zone 4 is less than or equal to 2.0 mg / L, and / or the oxidation-reduction potential at the tail end of the second aerobic zone 4 is less than or equal to +150.0 mV. The dissolved oxygen at the tail end of the gas release and deoxygenation zone 6 is less than or equal to 1.0 mg / L, and the oxidation-reduction potential at the tail end of the gas release and deoxygenation zone 6 is less than or equal to +100.0 mV. These parameters are used to monitor dissolved oxygen (DO) and oxidation-reduction potential (ORP) in the water. In practice, adjusting these parameters can help optimize the operation of the wastewater treatment system. For example, at the tail end of the second aerobic zone 4, if the dissolved oxygen is less than or equal to 1.0 mg / L and / or the oxidation-reduction potential is less than or equal to +100.0 mV, it may mean that it is necessary to increase aeration or increase oxygen supply to ensure that the wastewater is adequately oxidized here. At the tail end of the gas release and deoxygenation zone 6, if the dissolved oxygen is less than or equal to 1.0 mg / L and the oxidation-reduction potential is less than or equal to +100.0 mV, it may be necessary to increase aeration or increase oxygen supply to ensure that the wastewater is adequately oxidized here. By monitoring and adjusting the above parameters, the operation of the wastewater treatment system can be better monitored and controlled, ensuring that the system can operate efficiently and stably, and achieve the expected wastewater treatment effect.According to some embodiments of the present application, a return ratio from the anoxic zone 2 to the anaerobic zone 1 is less than or equal to 200%, and a circulation ratio from the anoxic zone 2 to the first aerobic zone 3 is greater than or equal to 300%. By controlling the return ratio from the anoxic zone 2 to the anaerobic zone 1 and the circulation ratio from the anoxic zone 2 to the aerobic zone, the anaerobic phosphorus release reaction, denitrifying phosphorus removal reaction, aerobic phosphorus uptake reaction, aerobic carbon removal reaction, nitrification reaction, and denitrification reaction can be controlled. Adjusting the return ratio and circulation ratio facilitates increasing the biological nitrogen and phosphorus removal efficiency of the biochemical reaction system.According to the description of the embodiments above, it can be seen that there is provided the BioDopp biochemical reaction system and wastewater treatment method, which have at least the following advantages:1. the use of three-phase separator 5 can reduce the use of mechanical equipment such as a sludge suction machine, a sludge scraper, or a sludge suction-scraping machine, save investment, lower operating costs, reduce equipment failures, and facilitate operation and maintenance, and further increase the existing tank volume for use as aerobic zones, increase the time for aerobic biochemical reaction, which is conducive to increasing the volume of treated water or saving floor space;2. the added gas release and deoxygenation zone 6 can significantly reduce the content of dissolved oxygen in the nitrified sludge mixed liquor returned to the anoxic zone 2, which can directly and effectively save carbon source addition and operating costs, and indirectly enhance the overall nitrogen and phosphorus removal efficiency of the reactor;3. after the division of aerobic zones (divided into the first aerobic zone 3 and the second aerobic zone 4), it is convenient to achieve different levels of aeration in different aerobic zones, which is more conducive to controlling the aerobic biochemical reaction rate and to controlling the content of the dissolved oxygen in the nitrified return liquor at the tail end of the aerobic zones to be low, thereby further enhancing the overall removal efficiency of pollutants such as carbon, nitrogen, and phosphorus in the reactor; and4. after adding substantial anaerobic functional zoning and adopting denitrification sludge return, the high-quality carbon source (VFAs) in the raw water can be utilized more efficiently for anaerobic phosphorus release, forming PHA or PHB in the microorganisms. Then, the denitrifying phosphorus removal reaction and the aerobic phosphorus uptake reaction are carried out in the subsequent anoxic zone 2 and aerobic zones, respectively, which greatly improves the phosphorus removal effect and achieves “dual carbon utilization”.It should be noted that the above embodiments are only used to explain the solutions of the present application, and are not limited thereto. Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by a person skilled in the art that modifications to the solutions recited in the foregoing embodiments and equivalent substitutions to a part of the features may be made. However, these modifications and substitutions do not make the essence of the corresponding solutions depart from the scope of the solutions of various embodiments of the present application.INDUSTRIAL APPLICABILITYThe present application provides a BioDopp biochemical reaction system and a wastewater treatment method. The system comprises an anaerobic zone, an anoxic zone, a first aerobic zone, a second aerobic zone, a three-phase separator, and a gas release and deoxygenation zone. The anaerobic zone is in communication with the anoxic zone, the anoxic zone is in communication with the first aerobic zone, the first aerobic zone is in communication with the second aerobic zone, the second aerobic zone is in communication with the gas release and deoxygenation zone, and the gas release and deoxygenation zone is in communication with the anoxic zone. The three-phase separator is arranged at the top of a tail end of the second aerobic zone, and the three-phase separator comprises a gas collection unit and a water collection unit. The gas collection unit comprises a main gas collection hood, an exhaust pipe, and a plurality of branch gas collection hood layers. The main gas collection hood covers the branch gas collection hood layers located at the top. A gas inlet end of the exhaust pipe is in communication with the main gas collection hood, and a gas exhaust end of the exhaust pipe is in communication with the first aerobic zone. The present application achieves dual carbon utilization, effectively saving carbon source consumption for nitrogen and phosphorus removal. It also features a simple structural layout, saves floor space, reduces construction and operating costs, and has good economic value and application prospects.
Claims
1. A BioDopp biochemical reaction system, comprising an anaerobic zone, an anoxic zone, a first aerobic zone, a second aerobic zone, a three-phase separator, and a gas release and deoxygenation zone; wherein a tail end of the anaerobic zone is in communication with the anoxic zone, a tail end of the anoxic zone is in communication with the first aerobic zone, a tail end of the first aerobic zone is in communication with the second aerobic zone, a tail end of the second aerobic zone is in communication with the gas release and deoxygenation zone, and a tail end of the gas release and deoxygenation zone is in communication with the anoxic zone;wherein the three-phase separator is arranged at the top of a tail end of the second aerobic zone, and the three-phase separator comprises a gas collection unit and a water collection unit;wherein the gas collection unit comprises a main gas collection hood, an exhaust pipe, and a plurality of branch gas collection hood layers, the main gas collection hood covers the branch gas collection hood layers located at the top, a gas inlet end of the exhaust pipe is in communication with the main gas collection hood, a gas exhaust end of the exhaust pipe is in communication with the first aerobic zone, the branch gas collection hood layer comprises a plurality of branch gas collection hoods arranged at intervals, a gas collection space is formed inside the branch gas collection hood, an outer wall of the branch gas collection hood forms a sludge guide surface, the branch gas collection hoods of adjacent branch gas collection hood layers are arranged in an alternating manner, a tortuous gap is formed between the branch gas collection hoods of the plurality of branch gas collection hood layers, and the tortuous gap is in communication with the second aerobic zone; andwherein the water collection unit comprises a water collection trough and a drainage channel, the water collection trough is arranged at the top of the main gas collection hood, and the drainage channel is in communication with the water collection trough. 2. The BioDopp biochemical reaction system of claim 1, further comprising a first flow passage, wherein a head end of the first flow passage is in communication with the tail end of the anoxic zone, and a tail end of the first flow passage is in communication with the first aerobic zone; andwherein the first flow passage is provided with a first return device, a head end of the first return device is in communication with the tail end of the anoxic zone, and a tail end of the first return device is in communication with the anaerobic zone. 3. The BioDopp biochemical reaction system of claim 1, further comprising a second flow passage, wherein a head end of the second flow passage is in communication with the anaerobic zone, and a tail end of the second flow passage is in communication with the anoxic zone. 4. The BioDopp biochemical reaction system of claim 1, further comprising a third flow passage, wherein the bottom of the third flow passage is in communication with the tail end of the second aerobic zone, the top of the third flow passage is in communication with the gas release and deoxygenation zone, and the third flow passage is provided with a airlift device;and / or, further comprising a fourth flow passage, wherein the bottom of the fourth flow passage is in communication with the tail end of the anoxic zone, the top of the fourth flow passage is in communication with the first aerobic zone, and the fourth flow passage is provided with a airlift device. 5. The BioDopp biochemical reaction system of claim 1, wherein the anoxic zone and / or the first aerobic zone are provided with guide walls for extending a water flow path. 6. The BioDopp biochemical reaction system of claim 1, wherein a horizontal inclination angle of the sludge guide surface is greater than or equal to 45°;wherein a spacing between the adjacent branch gas collection hoods in each of the branch gas collection hood layers is greater than or equal to 80 mm;wherein an overlap distance between the branch gas collection hoods in the adjacent branch gas collection hood layers is greater than or equal to 80 mm; andwherein a width of the tortuous gap is greater than or equal to 80 mm. 7. The BioDopp biochemical reaction system of claim 1, wherein the tail end of the second aerobic zone and / or the gas release and deoxygenation zone are provided with at least one of an DO online monitoring element and an ORP online monitoring element. 8. A wastewater treatment method based on the BioDopp biochemical reaction system of claim 1, comprising:introducing wastewater into the anaerobic zone, and conducting an anaerobic phosphorus release reaction after mixing carbon source in the wastewater with a denitrified sludge mixed liquor returned from the anoxic zone to the anaerobic zone, to obtain an anaerobic phosphorus release mixed liquor;introducing the anaerobic phosphorus release mixed liquor into a head end of the anoxic zone, and conducting a denitrifying nitrogen and phosphorus removal reaction and a denitrifying nitrogen and carbon removal reaction after mixing the anaerobic phosphorus release mixed liquor with a nitrified sludge mixed liquor, which has been subjected to degassing and dissolved oxygen removal in the gas release and deoxygenation zone, to obtain a denitrified sludge mixed liquor;returning a portion of the denitrified sludge mixed liquor to the anaerobic zone for circulation, and sequentially introducing another portion of the denitrified sludge mixed liquor into the first aerobic zone and the second aerobic zone to perform an aerobic phosphorus uptake reaction, an aerobic carbon removal reaction, and a nitrification reaction, to obtain a nitrified sludge mixed liquor; andintroducing the nitrified sludge mixed liquor into the three-phase separator, allowing effluent separated by gas collection and sedimentation to flow out, conveying gas to the first aerobic zone and / or the second aerobic zone for reuse, and allowing nitrified sludge separated by sedimentation to slide down along a path to the second aerobic zone, to accumulate at the tail end of the second aerobic zone, and to flow towards the gas release and deoxygenation zone, wherein a portion of the nitrified sludge is discharged at the tail end of the second aerobic zone and / or discharged from the gas release and deoxygenation zone, and another portion of the nitrified sludge mixed liquor is introduced into the head end of the anoxic zone via the gas release and deoxygenation zone for circulation. 9. The wastewater treatment method based on the BioDopp biochemical reaction system of claim 8, wherein the dissolved oxygen at the tail end of the second aerobic zone is controlled to be less than or equal to 2.0 mg / L and / or the oxidation-reduction potential at the tail end of the second aerobic zone is controlled to be less than or equal to +150.0 mV;and / or the dissolved oxygen at the tail end of the gas release and deoxygenation zone is controlled to be less than or equal to 1.0 mg / L, and / or the oxidation-reduction potential at the tail end of the gas release and deoxygenation zone is controlled to be less than or equal to +100.0 mV. 10. The wastewater treatment method based on the BioDopp biochemical reaction system of claim 8, wherein a return ratio from the anoxic zone to the anaerobic zone is less than or equal to 200%, and a circulation ratio from the anoxic zone to the first aerobic zone is greater than or equal to 300%.