Sewage denitrification treatment device

Abstract

The utility model discloses a sewage denitrification treatment device and belongs to the field of wastewater treatment. The reactor adopts an ingenious inner and outer cylinder overlapping design, and is matched with the design of a drainage device, a water distribution device, an aeration device and the like, so that sewage can circulate up and down in the reactor, sludge can be automatically settled, collected, lifted and refluxed in the reactor, and sludge particles can be automatically settled without a secondary sedimentation tank. A drainage device and a water distribution device are arranged for the reactor at the same time, an aeration device is designed to provide airflow and provide power for sewage circulation, continuous flow water inflow is achieved, anaerobic, anoxic, facultative and aerobic multi-aggregation microenvironments can be formed in the reactor at the same time, rapid biological nitrogen removal of sewage is achieved, the concentration of cultured aerobic granular sludge reaches 20000 mg / L, and the concentration of the cultured aerobic granular sludge reaches 20000 mg / L; and the granulation of the aerobic sludge is realized. The height of the whole reactor can reach 15-20 meters, so that the occupied area of the sewage denitrification treatment device is only 1 / 2-1 / 3 of that of a conventional process.

Description

Technical Field

[0001] This utility model belongs to the field of wastewater treatment, and relates to the biochemical treatment technology of organic wastewater, and in particular to a wastewater denitrification treatment device. Background Technology

[0002] Traditional wastewater denitrification processes mainly involve activated sludge processes and their variants, employing nitrification-denitrification for nitrogen removal. However, these processes still suffer from the following problems:

[0003] (a) The sludge concentration of the activated sludge process is generally between 2000 mg / L and 5000 mg / L. The sludge is characterized by being loose and flocculent, with generally poor settling properties. Therefore, it is necessary to use a secondary sedimentation tank to settle and separate the sludge. The process is long, complicated, and requires a large area.

[0004] (ii) Although there are systems that integrate the A tank, O tank and secondary sedimentation tank into one unit, the denitrification rate is often low and the denitrification effect is poor due to unclear interface conditions, resulting in a low rate of promotion and application. Utility Model Content

[0005] The purpose of this invention is to provide a novel wastewater denitrification treatment device that can produce sludge with a concentration of up to 20,000 mg / L. It has high wastewater denitrification efficiency, automatically completes sludge particle settling without the need for a secondary sedimentation tank, has a simple process, a short process flow, and adopts continuous flow water intake, which can improve the wastewater treatment rate. This solves the problems of low denitrification rate, long process flow, and large equipment footprint of the existing wastewater denitrification treatment processes.

[0006] To achieve the above objectives, this utility model provides the following solution:

[0007] This utility model provides a wastewater denitrification treatment device, comprising:

[0008] The reactor includes an outer cylinder and an inner cylinder fitted inside the outer cylinder, with an annular cavity formed between the inner cylinder and the outer cylinder. The top of the inner cylinder is lower than the top of the outer cylinder, and a communication port is provided between the bottom of the inner cylinder and the bottom of the outer cylinder, the communication port connecting the inner cylinder and the annular cavity.

[0009] A water distribution device is installed on the inner cylinder and located near the bottom end of the inner cylinder. The water distribution device is used to supply the wastewater to be treated to the inner cylinder.

[0010] An aeration device is installed inside the inner cylinder and is used to spray aeration airflow toward the top of the inner cylinder. The aeration airflow can drive the wastewater to be treated to flow toward the top of the inner cylinder and stir the wastewater to be treated.

[0011] A drainage device, installed on the outer cylinder, is used to drain the water inside the annular cavity;

[0012] A sludge collection and discharge device is installed at the bottom of the inner cylinder. The sludge collection and discharge device can collect sludge particles that have settled to the bottom of the inner cylinder and the annular cavity, and discharge the sludge particles.

[0013] Preferably, the aeration device is located in the region of 1 / 3 to 2 / 3 of the height of the inner cylinder, and the water distribution device is located inside the inner cylinder and below the aeration device.

[0014] Preferably, the aeration device includes:

[0015] An aeration tube frame is installed inside the inner cylinder. The aeration tube frame includes an annular aeration tube and a supporting aeration tube installed in the inner ring of the annular aeration tube. Both ends of the supporting aeration tube are connected to and communicate with the annular aeration tube.

[0016] An aerator assembly includes multiple aerators, with the aerators provided on both the annular aerator pipe and the supporting aerator pipe, and the aerator holes of any one of the aerators facing the top of the inner cylinder.

[0017] An air inlet pipe has one end connected to the annular aeration pipe or the supporting aeration pipe, and the other end passes through the inner cylinder and extends out of the inner cylinder; the air inlet pipe is used to connect to an air supply device to supply air to each of the aerators.

[0018] Preferably, the water distribution device includes:

[0019] An annular water distribution pipe with water distribution holes is provided on it. The annular water distribution pipe is coaxial with the inner cylinder and fixed to the inner wall of the inner cylinder.

[0020] The water inlet pipe has one end connected to the annular water distribution pipe, and the other end passes through the inner cylinder and the outer cylinder in sequence, and extends out of the outer cylinder; the water inlet pipe is used to connect to the wastewater source.

[0021] Preferably, the drainage device includes:

[0022] An annular water collection trough has an inlet on its inner ring. The annular water collection trough is coaxial with the outer cylinder and fixed to the inner wall of the outer cylinder. The annular water collection trough is located above the annular water distribution pipe and below the aeration device.

[0023] A drainage guide pipe is installed outside the outer cylinder, and the bottom end of the drainage guide pipe passes through the outer cylinder and is connected to the annular water collection trough.

[0024] Preferably, the drainage device further includes an annular drainage pipe, which is sleeved on the outside of the outer cylinder and arranged near the top of the outer cylinder; the top of the drainage guide pipe is connected to the annular drainage pipe.

[0025] Preferably, the height of the outer cylinder is 15 meters to 20 meters.

[0026] Preferably, the top and bottom of the inner cylinder are both open, and the bottom of the inner cylinder is supported above the bottom of the cylinder by a support block, so as to form a height gap between the bottom of the inner cylinder and the bottom of the cylinder, which serves as the communication port;

[0027] The outer wall of the inner cylinder and the inner wall of the outer cylinder are further supported and fixed by a support rod.

[0028] Preferably, the sludge collection and discharge device includes:

[0029] An annular mud collection pipe is provided at the bottom end of the inner cylinder, and multiple mud inlets are provided on the annular mud collection pipe;

[0030] The sludge discharge pipe is arranged at an angle, and its lower end is connected to the annular sludge collection pipe. Its upper end passes through the inner cylinder and the outer cylinder in sequence and extends out of the outer cylinder.

[0031] Preferably, the outer cylinder includes a straight cylinder section and a tapered cylinder section disposed at the bottom of the straight cylinder section, wherein the larger end of the tapered cylinder section is connected to the straight cylinder section, and the smaller end of the tapered cylinder section is the bottom of the cylinder.

[0032] The present invention achieves the following technical advantages over the prior art:

[0033] The wastewater denitrification treatment device disclosed in this utility model has a reasonable structural design. The reactor adopts a clever inner and outer cylinder stacking design, combined with drainage device, water distribution device and aeration device, so that the wastewater can circulate internally in the vertical direction within the reactor. The sludge can automatically complete the settling, collection and lifting return within the reactor. The sludge particles can be automatically settled without the need for a secondary settling tank. The process is simple and the process flow is short.

[0034] The wastewater denitrification treatment device disclosed in this utility model, by simultaneously equipping the reactor with a drainage device and a water distribution device, and designing an aeration device to provide airflow and power for wastewater circulation, achieves continuous water inflow while simultaneously forming a multi-state microenvironment of anaerobic, anoxic, facultative, and aerobic states within the reactor. This enables rapid biological denitrification of wastewater, not only cultivating granular aerobic sludge but also achieving a concentration of up to 20,000 mg / L, which is more than four times that of conventional processes, significantly improving wastewater denitrification efficiency.

[0035] The wastewater denitrification treatment device disclosed in this utility model has a reactor height of 15 to 20 meters. With the continuous flow water intake method, the wastewater denitrification treatment device occupies only 1 / 2 to 1 / 3 of the area of ​​conventional processes, which can reduce the equipment operation and maintenance costs. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the wastewater denitrification treatment device disclosed in an embodiment of this utility model.

[0038] Figure 2 This is a schematic diagram of the internal structure of the wastewater denitrification treatment device disclosed in an embodiment of this utility model.

[0039] Figure 3 This is a schematic diagram illustrating the working principle of the wastewater denitrification treatment device disclosed in an embodiment of this utility model.

[0040] Figure 4 This is a top view of the wastewater denitrification treatment device disclosed in an embodiment of this utility model.

[0041] Figure 5 This is a top view of the inner cylinder disclosed in an embodiment of this utility model.

[0042] In the figure, the reference numerals are as follows: 100-Wastewater denitrification treatment device; 1-Reactor; 11-Outer cylinder; 111-Straight cylinder section; 112-Conical cylinder section; 12-Inner cylinder; 13-Annular cavity; 14-Connecting port; 2-Water distribution device; 21-Annular water distribution pipe; 22-Inlet pipe; 3-Aeration device; 31-Annular aeration pipe; 32-Supporting aeration pipe; 33-Aerator; 34-Air inlet pipe; 4-Drainage device; 41-Annular water collection trough; 42-Inlet trough; 43-Drainage guide pipe; 44-Annular drainage pipe; 5-Sludge collection and discharge device; 51-Annular sludge collection pipeline; 52-Sludge discharge pipe; 6-Support block; 7-Support rod. Detailed Implementation

[0043] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0044] The purpose of this invention is to provide a novel wastewater denitrification treatment device that can produce sludge with a concentration of up to 20,000 mg / L. It has high wastewater denitrification efficiency, automatically completes sludge particle settling without the need for a secondary sedimentation tank, has a simple process, a short process flow, and adopts continuous flow water intake, which can improve the wastewater treatment rate. This solves the problems of low denitrification rate, long process flow, and large equipment footprint of existing wastewater denitrification treatment processes.

[0045] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0046] like Figures 1-3As shown, this embodiment provides a wastewater denitrification treatment device 100, including a reactor 1, a water distribution device 2, an aeration device 3, a drainage device 4, and a sludge collection and discharge device 5. The reactor 1 includes an outer cylinder 11 and an inner cylinder 12 fitted inside the outer cylinder 11. The top of the outer cylinder 11 is open and the bottom is closed. The inner cylinder 12 and the outer cylinder 11 are preferably coaxial, and an annular cavity 13 is formed between the inner cylinder 12 and the outer cylinder 11. The top of the inner cylinder 12 is open and the top of the inner cylinder 12 is lower than the top of the outer cylinder 11 to ensure that the sewage in the inner cylinder 12 can overflow smoothly into the annular cavity 13 through the top of the inner cylinder 12. A connecting port 14 is provided between the bottom of the inner cylinder 12 and the bottom of the outer cylinder 11, and the connecting port 14 connects the inner cylinder 12 and the annular cavity 13. A water distribution device 2 is provided on the inner cylinder 12 and is located near the bottom of the inner cylinder 12. The water distribution device 2 is used to provide the sewage to be treated to the inner cylinder 12. An aeration device 3 is provided inside the inner cylinder 12 and is used to spray aeration air towards the top of the inner cylinder 12. The aeration air can drive the sewage to be treated to flow from the bottom to the top of the inner cylinder 12 and has a stirring effect on the sewage to be treated. A drainage device 4 is installed on the outer cylinder 11 to discharge water from the annular cavity 13. Together with the water distribution device 2, it enables continuous water supply and drainage within the reactor 1, achieving dynamic flow of wastewater and continuous replacement with new wastewater. A sludge collection and discharge device 5 is installed at the bottom of the inner cylinder 12. Sludge particles settling at the bottom of the annular cavity 13 are collected at the bottom of the inner cylinder 12 through the aforementioned connecting port 14, allowing the sludge collection and discharge device 5 to collect the sludge particles settling at the bottom of the inner cylinder 12 and the bottom of the annular cavity 13. The aforementioned wastewater denitrification treatment device 100, through the arrangement of the reactor 1, water distribution device 2, aeration device 3, drainage device 4, and sludge collection and discharge device 5, allows wastewater to enter the inner cylinder 12. The rising airflow from the aeration device 3 carries the wastewater sequentially through the top of the inner cylinder 12, the annular cavity 13, the bottom of the annular cavity 13, and the connecting port 14, ultimately flowing back to the inner cylinder 12. This achieves an internal circulation of wastewater centered on the inner cylinder 12 wall. The treated water can be discharged to the outside of the outer cylinder 11 through the drainage device 4. This design allows the sludge to automatically settle, collect, and be lifted back into the reactor 1, eliminating the need for a secondary settling tank and achieving complete separation of hydraulic retention time (HRT) and sludge retention time (SRT). The process is simple and the flow is short.

[0047] In some implementations, such as Figure 2 and Figure 3 As shown, the aeration device 3 is preferably located within the range of 1 / 3 to 2 / 3 of the height of the inner cylinder 12, with 1 / 2 of the height being optimal. This allows the overall height of the reactor 1 to be set to 15 to 20 meters, while conventional aeration tanks are typically less than 8 meters deep. The water distribution device 2 is located inside the inner cylinder 12, and preferably below the aeration device 3.

[0048] In some implementations, such as Figure 2 and Figure 5 As shown, the aeration device 3 includes an aeration pipe frame, an aerator assembly, and an air inlet pipe 34. The aeration pipe frame is located inside the inner cylinder 12 and includes an annular aeration pipe 31 and a supporting aeration pipe 32 located within the inner ring of the annular aeration pipe 31. Both ends of the supporting aeration pipe 32 are connected to and communicate with the annular aeration pipe 31. Both the annular aeration pipe 31 and the supporting aeration pipe 32 are preferably made of rigid pipes, such as metal pipes. The annular aeration pipe 31 and the supporting aeration pipe 32 can be welded together. The annular aeration pipe 31 and the supporting aeration pipe 32 serve as both the installation support structure for the entire aerator assembly and the air supply channel for the aerator assembly. The annular aeration pipe 31 can adopt a circular, polygonal, or other closed-loop structure. The supporting aeration pipe 32 is preferably a straight pipe structure, supported within the inner ring of the annular aeration pipe 31. Figure 5 Taking the hexagonal structure shown as an example, the supporting aeration pipe 32 is supported at the center of the annular aeration pipe 31. The supporting aeration pipe 32 can both improve the structural strength of the annular aeration pipe 31 and increase the number of aerators that can be installed on the aeration pipe frame. The aerator group includes multiple aerators 33. Aerators 33 are provided on both the annular aeration pipe 31 and the supporting aeration pipe 32, and the aeration holes of any aerator 33 face the top of the inner cylinder 12. Figure 5 As shown, an aerator 33 is installed at each corner of the hexagonal annular aeration pipe 31, and an aerator 33 is also installed at the center of the supporting aeration pipe 32. One end of the air inlet pipe 34 is connected to the annular aeration pipe 31 or the supporting aeration pipe 32, and the other end of the air inlet pipe 34 passes through the inner cylinder 12 and extends outside the inner cylinder 12; the air inlet pipe 34 is used to connect to the air supply device to supply air to each aerator 33. The air supply device includes, but is not limited to, a blower. The air inlet pipe 34 is also made of rigid pipes such as PVC pipes or metal pipes to provide support for the entire aeration device 3.

[0049] When the aforementioned aeration device 3 is installed inside the inner cylinder 12, the air inlet pipe 34, which penetrates the wall of the inner cylinder 12, provides support for the aeration pipe frame. To ensure the stability of the aeration pipe frame, a support block can also be installed on the inner wall of the inner cylinder 12, and the annular aeration pipe 31 can be fixed to the support block. The perforation formed in the inner ring of the annular aeration pipe 31 allows sewage to pass through smoothly.

[0050] In some implementations, such as Figure 3 and Figure 4As shown, the water distribution device 2 includes an annular water distribution pipe 21 and an inlet pipe 22. The annular water distribution pipe 21 has several water distribution holes and is coaxial with the inner cylinder 12, fixed to the inner wall of the inner cylinder 12. To ensure the stability of the annular water distribution pipe 21, a support block is preferably installed on the inner wall of the inner cylinder 12, and the annular water distribution pipe 21 is fixed to the support block. One end of the inlet pipe 22 is connected to the annular water distribution pipe 21, and the other end of the inlet pipe 22 passes through the inner cylinder 12 and the outer cylinder 11 in sequence, extending out of the outer cylinder 11. The inlet pipe 22 is used to connect to a wastewater source. The wastewater source can be a storage tank, water reservoir, or similar container holding wastewater to be treated.

[0051] In some implementations, such as Figures 2-4 As shown, the drainage device 4 includes an annular water collection trough 41 and a drainage guide pipe 43. The annular water collection trough 41 has an inlet trough 42 on its inner ring. The annular water collection trough 41 is located inside the annular cavity 13 and fixed to the inner wall of the outer cylinder 11. The annular water collection trough 41 is coaxial with the outer cylinder 11. Figure 2 and Figure 3 As shown, the annular water collection trough 41 is preferably located above the annular water distribution pipe 21 and below the aeration device 3. To ensure the stability of the annular water collection trough 41, a support block is preferably provided on the inner wall of the inner cylinder 12, and the annular water collection trough 41 is fixed to the support block. The aforementioned drainage guide pipe 43 is located outside the outer cylinder 11, and the bottom end of the drainage guide pipe 43 passes through the outer cylinder 11 and communicates with the annular water collection trough 41.

[0052] In some embodiments, considering that the water flow direction in the annular cavity 13 is always towards the bottom of the cylinder, it is preferable that the water inlet 42 of the annular water collection tank 41 is set downwards, which can prevent sludge particles from entering the annular water collection tank 41 and achieve the effect of mud-water separation.

[0053] In some embodiments, the drainage device 4 further includes an annular drain pipe 44, which is sleeved on the outside of the outer cylinder 11 and arranged near the top of the outer cylinder 11; the top of the drainage guide pipe 43 communicates with the annular drain pipe 44. To ensure the stability of the drainage guide pipe 43, it is preferable to provide a support block on the outer wall of the outer cylinder 11 and fix the drainage guide pipe 43 to the support block. The aforementioned annular drain pipe 44 has a drain outlet or is connected to a drainage pipe to smoothly discharge the sewage collected in the annular water collection tank 41 to the outside of the reactor 1.

[0054] In some embodiments, the top and bottom of the inner cylinder 12 are both open, and the bottom of the inner cylinder 12 is higher than the bottom of the outer cylinder 11, and is supported above the bottom by support blocks 6, so as to form a height gap between the bottom of the inner cylinder 12 and the bottom of the outer cylinder 11. This height gap serves as the aforementioned communication port 14, in which case the interior of the inner cylinder 12 communicates with the annular cavity 13. As a preferred embodiment, the bottom of the inner cylinder 12 is preferably provided with multiple support blocks 6 at intervals, such as three to six, and a height gap (i.e., communication port 14) is formed between any two adjacent support blocks 6. To enhance the connection strength of the inner cylinder 12 within the outer cylinder 11, the outer side wall of the inner cylinder 12 and the inner side wall of the outer cylinder 11 are preferably further supported and fixed by support rods 7, such as... Figure 4 As shown, three support rods 7 are evenly distributed inside the annular cavity 13. The support rods 7 and the support block 6 cooperate to ensure the connection strength between the inner cylinder 12 and the outer cylinder 11.

[0055] In some implementations, such as Figure 2 and Figure 3 As shown, the sludge collection and discharge device 5 includes an annular sludge collection pipe 51 and a sludge discharge pipe 52. The annular sludge collection pipe 51 is located directly below the inner cylinder 12 and within the area enclosed by the support block 6. The annular sludge collection pipe 51 is preferably fixed to the bottom of the outer cylinder 11. Multiple sludge inlets are provided on the annular sludge collection pipe 51 to allow sludge particles to enter the annular sludge collection pipe 51 through the inlets. The sludge discharge pipe 52 is arranged at an angle, such as... Figure 2 and Figure 3 As shown, the lower end of the sludge discharge pipe 52 is connected to the annular sludge collection pipe 51, and the upper end of the sludge discharge pipe 52 passes through the inner cylinder 12 and the outer cylinder 11 in sequence before extending out of the outer cylinder 11. Based on the design of the above-mentioned sludge collection and discharge device 5, there is no need to install a sludge discharge pump; sludge discharge can be achieved by utilizing the pressure difference between the inside and outside water.

[0056] In some embodiments, the outer cylinder 11 includes a straight section 111 and a conical section 112 disposed at the bottom of the straight section 111, with the larger end of the conical section 112 connected to the straight section 111 and the smaller end of the conical section 112 forming the bottom of the cylinder. The inclined wall of the conical section 112 facilitates the guidance of sludge particles to the connecting port 14, allowing the sludge particles settling in the reactor 1 to collect at the connecting port 14 and smoothly enter the annular sludge collection pipe 51 through the connecting port 14.

[0057] In some embodiments, the height of the outer cylinder 11 is preferably 15 to 20 meters. The height of the outer cylinder 11 represents the height of the entire reactor 1. Based on the above design of the outer cylinder 11, the distance between the bottom end of the inner cylinder 12 and the bottom of the outer cylinder 11 (i.e., the height gap) is preferably 20 cm.

[0058] The working principle of the wastewater denitrification treatment device 100 described in this embodiment will be explained in detail below.

[0059] The wastewater to be treated enters the inner cylinder 12 through the annular water distribution pipe 21 at the bottom of the inner cylinder 12. It is lifted by the aeration airflow from each aerator 33. At the same time, the aeration airflow mixes with the wastewater to form an air-water mixture, which rises in the inner cylinder 12. After the air-water mixture flows to the top of the inner cylinder 12, it overflows from the top of the inner cylinder 12 into the inner and outer cylinder reaction zone (i.e., the annular cavity 13). It flows from top to bottom in the inner and outer cylinder reaction zone (i.e., the annular cavity 13) and then flows back to the inner cylinder 12 through the connecting port 14. Thus, the wastewater forms an internal circulation flow in the upper and lower directions in the reactor 1.

[0060] like Figure 3 As shown, because the aeration device 3 is positioned in the middle of the inner cylinder 12, and the overall height of the reactor 1 is relatively high, distinct aerobic, facultative, anoxic, and anaerobic zones are formed during the wastewater circulation reaction. Specifically:

[0061] ① Wastewater first enters the anaerobic zone for pre-denitrification. Heterotrophic denitrifying bacteria use organic matter as a carbon and energy source under anaerobic conditions to reduce nitrates to nitrogen gas. The function of the anaerobic zone is to decompose organic matter and remove total nitrogen. The main reaction formulas are as follows:

[0062] 6NO3 - +5CH з OH + 6H + →3N₂↑+5CO₂↑+13H₂O

[0063] 2NO2 - +3CH3OH+2H + →N₂↑+3CO₂↑+4H₂O

[0064] 10NO3 - +C6H 12 O6+4H + →5N₂↑+6CO₂↑+8H₂O

[0065] 4NO2 - +C6H 12 O6+4H + →2N₂↑+6CO₂↑+6H₂O

[0066] ② Subsequently, the wastewater is lifted upwards by the aeration airflow, simultaneously mixing with the wastewater to form an air-water mixture. This mixture rises and enters the aerobic zone, where dissolved oxygen levels are typically between 2 mg / L and 5 mg / L. In the aerobic zone, microorganisms decompose the organic matter in the wastewater into carbon dioxide and water through aerobic respiration, thereby reducing the chemical oxygen demand (COD) and biochemical oxygen demand (BOD) of the wastewater. Simultaneously, the organic matter is oxidized into nitrate nitrogen under the action of aerobic microorganisms. The main reaction formulas are as follows:

[0067] C6H 12O6 + 6O2 → 6CO2 + 6H2O

[0068] 2NH4 + 3O2 → 2NO2 - +4H + +2H2O

[0069] 2NO2 + O2 → 2NO3 -

[0070] ③ Subsequently, the gas-water mixture overflows from the top of the inner cylinder 12 into the anaerobic and anoxic zones of the annular cavity 13, flowing downwards within the annular cavity 13. The anaerobic zone is a region where aerobic and anaerobic environments coexist, with dissolved oxygen typically between 0.2 and 0.5 mg / L, while the anoxic zone typically has dissolved oxygen levels below 0.3 mg / L. The anaerobic and anoxic zones represent the transitional biochemical reaction zones from aerobic to anaerobic environments. Figure 3 In the middle, the anoxic zone is located inside the annular cavity 13, and the anoxic zone is located above the anoxic zone and below the top of the inner cylinder 12.

[0071] In summary, by simultaneously creating aerobic, facultative, anoxic, and anaerobic zones within the same reactor 1, multiple microenvironments and bioreactors are established, achieving a multi-state reactor. Symbiotic and mutualistic interactions exist among different microorganisms, further enriching the variety and quantity of microbial communities within reactor 1. In the aerobic zone, organic matter is oxidized to nitrate, while in the anoxic and anaerobic zones, nitrate is reduced to N2, rapidly achieving biological denitrification of wastewater.

[0072] In addition, during the wastewater circulation process, the annular water collection tank 41 near the bottom of the cylinder can act as a three-phase separator. That is, in the annular cavity 13, the airflow goes upward and the sludge settles downward. At the same time, water enters the annular water collection tank 41 through the inlet 42 and is discharged out through the drainage guide pipe 43 and the annular drainage pipe 44 in sequence.

[0073] Inside the inner cylinder 12, the air-water mixture is subjected to strong hydraulic agitation by a sufficient aeration flow. Simultaneously, the generation and collapse of numerous bubbles exert significant shearing and screening effects on the sludge, washing away loose microbial aggregates while retaining granular sludge with stronger structure and settling properties. Calcium and magnesium cations can combine with acidic groups in EPS (extracellular polymeric substances), increasing bridging between microbial cells, promoting sludge granulation, and ultimately forming granular sludge. Due to the inclined design of the sludge discharge pipe 52, a height difference is created between its inlet and outlet ends. When water intake and aeration cease in the inner cylinder 12, the granular sludge settles and converges at the bottom of the inner cylinder 12, and is discharged externally through the hydraulic height difference. "Internal and external hydraulic height difference" refers to the height difference between the liquid level inside reactor 1 and the external sludge discharge pipe 52. Reactor 1 is set above ground, not buried underground. The height of reactor 1 is 15 to 20 meters. The sewage inside reactor 1 has a water pressure equivalent to 15 to 20 meters, which can discharge the sludge at the bottom.

[0074] The wastewater denitrification treatment device 100 proposed in this utility model has the following beneficial effects:

[0075] (I) This utility model provides an integrated device for polymerized sludge, granulated sludge, and rapid biological denitrification. It can not only continuously feed water, but also simultaneously create anoxic, facultative, and aerobic microenvironments inside the reactor, thereby accelerating the denitrification efficiency of wastewater.

[0076] (ii) The reactor adopts a clever inner and outer cylinder stacked design, combined with drainage device, water distribution device and aeration device, so that the sewage can circulate up and down in the reactor. The sludge can automatically complete the settling, collection and lifting return in the reactor, eliminating the need for a secondary settling tank and simplifying the structure.

[0077] (III) Through the special structural design inside the reactor, aerobic sludge granules are cultivated. The concentration of aerobic granular sludge can reach 20,000 mg / L, which is more than 4 times that of conventional processes, greatly improving the efficiency of wastewater denitrification.

[0078] (iv) The height of the entire reactor can reach 15 to 20 meters. With the continuous flow water intake method, the wastewater denitrification treatment device occupies only 1 / 2 to 1 / 3 of the area of ​​conventional processes.

[0079] This utility model uses specific examples to illustrate its principles and implementation methods. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the idea of ​​this utility model. In summary, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A wastewater denitrification treatment device, characterized in that, include: The reactor (1) includes an outer cylinder (11) and an inner cylinder (12) fitted inside the outer cylinder (11). An annular cavity (13) is formed between the inner cylinder (12) and the outer cylinder (11). The top of the inner cylinder (12) is lower than the top of the outer cylinder (11), and a communication port (14) is provided between the bottom of the inner cylinder (12) and the bottom of the outer cylinder (11). The communication port (14) connects the inner cylinder (12) and the annular cavity (13). A water distribution device (2) is installed on the inner cylinder (12) and is located near the bottom end of the inner cylinder (12). The water distribution device (2) is used to supply the wastewater to be treated to the inner cylinder (12). An aeration device (3) is installed inside the inner cylinder (12) and is used to spray aeration airflow toward the top of the inner cylinder (12). The aeration airflow can drive the wastewater to be treated to flow toward the top of the inner cylinder (12) and stir the wastewater to be treated. A drainage device (4) is provided on the outer cylinder (11) for draining water from the annular cavity (13); The sludge collection and discharge device (5) is located at the bottom of the inner cylinder (12). The sludge collection and discharge device (5) can collect sludge particles that have settled to the bottom of the inner cylinder (12) and the annular cavity (13) and discharge the sludge particles.

2. The wastewater denitrification treatment device according to claim 1, characterized in that, The aeration device (3) is located in the area of ​​1 / 3 to 2 / 3 of the height of the inner cylinder (12), and the water distribution device (2) is located inside the inner cylinder (12) and below the aeration device (3).

3. The wastewater denitrification treatment device according to claim 2, characterized in that, The aeration device (3) includes: An aeration tube frame is installed inside the inner cylinder (12). The aeration tube frame includes an annular aeration tube (31) and a supporting aeration tube (32) installed in the inner ring of the annular aeration tube (31). Both ends of the supporting aeration tube (32) are connected and communicate with the annular aeration tube (31). An aerator group includes multiple aerators (33), and the aerators (33) are provided on both the annular aeration pipe (31) and the supporting aeration pipe (32), and the aeration holes of any aerator (33) face the top of the inner cylinder (12). An air inlet pipe (34) has one end connected to the annular aeration pipe (31) or the supporting aeration pipe (32), and the other end passes through the inner cylinder (12) and extends out of the inner cylinder (12); the air inlet pipe (34) is used to connect an air supply device to supply air to each of the aerators (33).

4. The wastewater denitrification treatment device according to claim 2 or 3, characterized in that, The water distribution device (2) includes: An annular water distribution pipe (21) is provided with water distribution holes. The annular water distribution pipe (21) is coaxial with the inner cylinder (12) and fixed to the inner wall of the inner cylinder (12). The water inlet pipe (22) is connected at one end to the annular water distribution pipe (21), and at the other end passes through the inner cylinder (12) and the outer cylinder (11) in sequence, and extends out of the outer cylinder (11); the water inlet pipe (22) is used to connect to the wastewater source.

5. The wastewater denitrification treatment device according to claim 4, characterized in that, The drainage device (4) includes: The annular water collection trough (41) has an inlet trough (42) on its inner ring. The annular water collection trough (41) is coaxial with the outer cylinder (11) and fixed to the inner wall of the outer cylinder (11). The annular water collection trough (41) is located above the annular water distribution pipe (21) and below the aeration device (3). A drainage guide pipe (43) is disposed outside the outer cylinder (11), and the bottom end of the drainage guide pipe (43) passes through the outer cylinder (11) and is connected to the annular water collection trough (41).

6. The wastewater denitrification treatment device according to claim 5, characterized in that, The drainage device (4) further includes an annular drainage pipe (44), which is sleeved on the outside of the outer cylinder (11) and arranged near the top of the outer cylinder (11); the top of the drainage guide pipe (43) is connected to the annular drainage pipe (44).

7. The wastewater denitrification treatment device according to any one of claims 1 to 3, characterized in that, The outer cylinder (11) has a height of 15 meters to 20 meters.

8. The wastewater denitrification treatment device according to any one of claims 1 to 3, characterized in that, The top and bottom of the inner cylinder (12) are both open, and the bottom of the inner cylinder (12) is supported above the bottom of the cylinder by a support block (6) to form a height gap between the bottom of the inner cylinder (12) and the bottom of the cylinder, which serves as the communication port (14). The outer wall of the inner cylinder (12) and the inner wall of the outer cylinder (11) are also supported and fixed by a support rod (7).

9. The wastewater denitrification treatment device according to claim 8, characterized in that, The sludge collection and discharge device (5) includes: An annular mud collection pipe (51) is provided at the bottom end of the inner cylinder (12), and multiple mud inlets are provided on the annular mud collection pipe (51); The mud discharge pipe (52) is arranged at an angle, and the lower end of the mud discharge pipe (52) is connected to the annular mud collection pipe (51). The upper end of the mud discharge pipe (52) passes through the inner cylinder (12) and the outer cylinder (11) in sequence, and then extends out of the outer cylinder (11).

10. The wastewater denitrification treatment device according to claim 9, characterized in that, The outer cylinder (11) includes a straight cylinder section (111) and a conical cylinder section (112) disposed at the bottom of the straight cylinder section (111), wherein the large end of the conical cylinder section (112) is connected to the straight cylinder section (111), and the small end of the conical cylinder section (112) is the bottom of the cylinder.

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