A carbon source screening device for enhanced denitrification of sewage treatment

Abstract

This invention belongs to the field of wastewater treatment technology, specifically a carbon source screening device for enhanced denitrification in wastewater treatment. It includes a wastewater tank, with a wastewater inlet pipe installed through one side of the outer wall. A Venturi tube is fixedly connected to one end of the wastewater inlet pipe via a flange. A mesh drum is installed on one end of the Venturi tube. A self-rotating backwashing mechanism is installed inside both the Venturi tube and the mesh drum. The self-rotating backwashing mechanism includes a central tube, an axial flow impeller, a connecting rod, a water inlet pipe, a backwashing pipe, and a flushing nozzle. This invention, through the coordinated operation of the wastewater tank, Venturi tube, self-rotating backwashing mechanism, and scum discharge mechanism, automatically achieves mesh drum rotation, mesh drum backwashing, and simultaneous scum discharge using the power of the wastewater's own water flow. No external power is required, and the entire process is fully automated, effectively solving the problems of difficult scum removal and cleaning, and achieving integrated continuous screening and scum removal.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, and in particular to a carbon source screening device for enhanced denitrification in wastewater treatment. Background Technology

[0002] In the enhanced denitrification process of wastewater treatment, a carbon source needs to be added to the wastewater to promote the denitrification reaction, reducing nitrate nitrogen in the water to nitrogen gas, thereby achieving nitrogen removal and purification. Carbon source screening and solid-liquid separation are key steps in this process, mainly used to intercept suspended solids, flocs, and scum generated during the reaction in the wastewater, preventing impurities from entering subsequent treatment units, while ensuring sufficient mixing and contact between the carbon source and the wastewater. Such equipment typically needs to have functions such as continuous screening, automatic scum removal, and anti-clogging to ensure the stable and efficient operation of the denitrification system and improve wastewater treatment results.

[0003] In existing facilities, the carbon source screening equipment used to enhance denitrification is significantly inadequate, causing numerous problems in actual operation: First, the reaction between wastewater and carbon source agents will produce a large amount of scum and flocculent impurities. These substances have low density and high viscosity, and are very easy to adhere to the screening screen and the inner wall of the equipment. Conventional equipment cannot achieve automatic cleaning, and manual cleaning is required to be stopped regularly, which is cumbersome and labor-intensive. Secondly, the scum is difficult to clean, which not only easily causes the mesh to become clogged, affecting the screening efficiency and water flow, but also leads to the accumulation and decay of impurities, producing odors and breeding bacteria, thus reducing the efficiency of denitrification. In addition, existing equipment mostly relies on external power sources such as motors and water pumps to drive rotation and flushing, resulting in high energy consumption, complex structure, and many failure points. It also suffers from insufficient stability during long-term continuous operation, short maintenance cycles, and high costs. Although some equipment has a simple screening function, it does not achieve coordinated linkage between screening, backwashing, and slag discharge. Scum easily accumulates in the dead corners of the equipment, causing secondary pollution and making it difficult to meet the operational requirements of modern sewage treatment plants. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention provides a carbon source screening device for enhanced denitrification in wastewater treatment, which overcomes the shortcomings of the prior art and effectively solves the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A carbon source screening device for enhanced denitrification in wastewater treatment includes a wastewater tank. A wastewater inlet pipe is installed through one side of the outer wall of the wastewater tank, and a venturi tube is fixedly connected to one end of the outer wall of the wastewater inlet pipe via a flange. A mesh drum is provided on one end of the outer wall of the venturi tube, and a self-rotating backwash mechanism is provided inside the venturi tube and the mesh drum. The self-rotating backwash mechanism includes a core tube, an axial flow impeller, connecting rods, a water inlet pipe, a backwash pipe, and flushing nozzles. The connecting rods are welded to the inner walls of both ends of the mesh drum. The core tube is welded between two sets of connecting rods. The axial flow impeller is installed on the outer wall of the core tube. A rotary joint is installed at the end of the core tube away from the axial flow impeller. The water inlet pipe is rotatably connected to the outer wall of one end of the core tube through the rotary joint. The backwash pipe is fixedly connected to the outer wall of one end of the water inlet pipe. An array of flushing nozzles is installed on the bottom outer wall of the backwash pipe. A slag discharge mechanism is provided on the top inner wall of the mesh drum.

[0006] Preferably, the slag discharge mechanism includes a slag collection trough, a slag baffle plate, and a slag discharge pipe. The slag collection trough is located on the top of the inner wall of the mesh drum, the slag baffle plate is welded to the inner wall of the slag collection trough and is tightly attached to the top inner wall of the mesh drum, and the slag discharge pipe is fixedly installed on the outer wall of one end of the slag collection trough.

[0007] Preferably, the spindle is disposed through the inner spindle of the mesh drum, and the flushing nozzle is located above the mesh drum.

[0008] Preferably, the inner walls of the sewage tank are welded with symmetrically distributed crossbeams, and the outer wall of the top of the crossbeams is welded with mounting brackets. The spindle is rotatably connected between the two mounting brackets through bearings.

[0009] Preferably, the venturi tube includes an inlet, a outlet, and an acceleration port. The inlet is fixedly connected to the outer wall of one end of the wastewater inlet pipe via a flange, the outlet is fixedly connected to the outer wall of one of the mounting brackets via a flange, and the acceleration port is welded between the inlet and the outlet. The axial flow impeller is located inside the acceleration port.

[0010] Preferably, a filter screen is installed at one end of the axial tube near the axial flow impeller, and a scraper is fixedly connected to the inner wall of the acceleration port of the venturi tube, the scraper being tightly attached to one side of the outer wall of the filter screen.

[0011] Preferably, a water-blocking and dispersing disc is welded to the outer wall of the axial tube near the Venturi tube, and axially distributed dispersing strips are provided on one side of the outer wall of the water-blocking and dispersing disc, which is located inside the mesh drum.

[0012] Preferably, the bottom inner wall of the sewage tank is covered with a gravel layer, and the top inner wall of the gravel layer is covered with a quartz sand filter layer.

[0013] Preferably, a fixing plate is welded to the top of each of the two mounting brackets, and a backwash pipe is installed between the two fixing plates. A clamp is fixedly connected to the inner wall of the top of the other mounting bracket by screws, and a slag discharge pipe is installed through the inner wall of the clamp.

[0014] Preferably, a valve is installed on the outer wall of the water inlet pipe.

[0015] The beneficial effects of this invention are as follows: 1. The carbon source screening equipment for enhanced denitrification in wastewater treatment of the present invention, through the linkage of wastewater tank, venturi tube, self-rotating backwash mechanism and slag discharge mechanism, automatically realizes the rotation of the screen drum, backwashing of the screen drum and simultaneous discharge of scum by utilizing the water flow power of the wastewater itself. No external power is required, and the whole process is fully automated. It effectively solves the problems of difficult scum removal and cleaning, and realizes the integration of continuous screening and slag removal. 2. The carbon source screening equipment for enhanced denitrification in wastewater treatment of the present invention uses a venturi tube to accelerate the water flow and drive the axial flow impeller to rotate, which in turn drives the shaft tube and the mesh drum to rotate. In conjunction with the flushing nozzle, the mesh surface is automatically backwashed, which effectively prevents the mesh from clogging, ensures smooth screening, eliminates the need for manual cleaning, and reduces maintenance costs. 3. The carbon source screening equipment for enhanced denitrification in wastewater treatment of the present invention has a slag discharge mechanism installed inside the upper part of the mesh drum. The slag baffle can continuously scrape the floating slag attached to the mesh surface and send it into the slag collection tank, and discharge it uniformly through the slag discharge pipe, so as to realize the simultaneous generation and cleaning of floating slag, avoid the accumulation and decay of impurities, and keep the equipment clean. 4. The carbon source screening device for enhanced denitrification in wastewater treatment of the present invention uses a venturi tube in conjunction with a filter screen and scraper to filter wastewater while accelerating its flow. The scraper automatically cleans impurities from the surface of the filter screen to prevent clogging and ensures stable backwashing of the flushing nozzles, providing favorable conditions for subsequent screening and denitrification reactions. Attached Figure Description

[0016] Figure 1 This is a three-dimensional schematic diagram of the overall structure of a carbon source screening device for enhanced denitrification in wastewater treatment proposed in this invention. Figure 1 ; Figure 2 This is a three-dimensional schematic diagram of the overall structure of a carbon source screening device for enhanced denitrification in wastewater treatment proposed in this invention. Figure 2 ; Figure 3 This is a schematic diagram of the internal structure of a wastewater tank in a carbon source screening device for enhanced denitrification in wastewater treatment, as proposed in this invention. Figure 4 This is a schematic diagram of the mounting frame connection structure of a carbon source screening device for enhanced denitrification in wastewater treatment proposed in this invention; Figure 5 This is a schematic diagram of the internal structure of a venturi tube in a carbon source screening device for enhanced denitrification in wastewater treatment, as proposed in this invention. Figure 6 This is a schematic diagram of the slag discharge mechanism of a carbon source screening device for enhanced denitrification in wastewater treatment proposed in this invention; Figure 7 This is a schematic diagram of a mesh drum structure for a carbon source screening device for enhanced denitrification in wastewater treatment, as proposed in this invention.

[0017] In the diagram: 1. Sewage tank; 2. Wastewater inlet pipe; 3. Venturi tube; 4. Shaft tube; 5. Axial flow impeller; 6. Connecting rod; 7. Mesh drum; 8. Water inlet pipe; 9. Backwash pipe; 10. Flushing nozzle; 11. Slag discharge mechanism; 111. Slag collection trough; 112. Slag baffle plate; 113. Slag discharge pipe; 12. Crossbeam; 13. Mounting frame; 14. Water inlet; 15. Drain outlet; 16. Accelerator port; 17. Filter screen; 18. Scraper bar; 19. Water-blocking and dispersing disc; 20. Dispersing bar; 21. Gravel layer; 22. Quartz sand filter layer; 23. Fixing plate; 24. Clamp; 25. Valve. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0019] Reference Figures 1-7 Example 1: A carbon source screening device for enhanced denitrification in wastewater treatment includes a wastewater tank 1. A wastewater inlet pipe 2 is installed through one side of the outer wall of the wastewater tank 1. A venturi tube 3 is fixedly connected to one end of the outer wall of the wastewater inlet pipe 2 via a flange. A mesh drum 7 is provided on one end of the outer wall of the venturi tube 3. A self-rotating backwash mechanism is provided inside the venturi tube 3 and the mesh drum 7. The self-rotating backwash mechanism includes a core tube 4, an axial flow impeller 5, a connecting rod 6, a water inlet pipe 8, a backwash pipe 9, and a flushing nozzle 10. The connecting rod 6 is welded to the inner walls of both ends of the mesh drum 7. The core tube 4 is welded between two sets of connecting rods 6. The axial flow impeller 5 is installed on the outer wall of the core tube 4. A rotary joint is installed at the end of the core tube 4 away from the axial flow impeller 5. The water inlet pipe 8 is rotatably connected to the outer wall of one end of the core tube 4 through the rotary joint. The backwash pipe 9 is fixedly connected to the outer wall of one end of the water inlet pipe 8. The array of flushing nozzles 10 is installed on the bottom outer wall of the backwash pipe 9.

[0020] Through the above scheme, the sewage tank 1 provides a stable space for sewage treatment and carbon source screening. The wastewater inlet pipe 2 is used to continuously introduce sewage to be treated. The Venturi tube 3 accelerates the water flow through cross-sectional contraction, providing a stable power source for self-rotation. The self-rotating backwash mechanism drives the axial flow impeller 5 to rotate with the power of water flow, which in turn drives the shaft tube 4 and the mesh drum 7 to rotate synchronously, realizing dynamic continuous screening. The water inlet pipe 8, backwash pipe 9 and flushing nozzle 10 form a stable backwashing passage, which can fully cover the mesh surface during the rotation of the mesh drum 7. No external motor or water pump is required throughout the process. Screening and slag removal are automatically completed by utilizing the energy of the water flow itself. The structure is simple and the operation is reliable.

[0021] In this embodiment, the self-rotating backwash mechanism uses the Venturi tube 3 to accelerate the water flow and drive the axial flow impeller 5 to rotate, which in turn drives the shaft tube 4 and the mesh drum 7 to rotate. In conjunction with the flushing nozzle 10, the mesh surface is automatically backwashed, which effectively prevents the mesh from clogging, ensures smooth screening, eliminates the need for manual cleaning, and reduces maintenance costs.

[0022] In embodiment 2, a slag discharge mechanism 11 is provided on the inner wall of the top of the mesh drum 7. The slag discharge mechanism 11 includes a slag collection trough 111, a slag baffle plate 112, and a slag discharge pipe 113. The slag collection trough 111 is located at the top of the inner wall of the mesh drum 7. The slag baffle plate 112 is welded to the inner wall of the slag collection trough 111 and is tightly attached to the top inner wall of the mesh drum 7. The slag discharge pipe 113 is fixedly installed on the outer wall of one end of the slag collection trough 111.

[0023] With the above scheme, the baffle plate 112 in the slag discharge mechanism 11 is always in close contact with the inner side of the mesh surface, which can continuously scrape off the attached slag and flocs and guide them into the slag collection tank 111. The slag collection tank 111 is arranged at an inclination, which can use gravity to stably transport the slag to the slag discharge pipe 113 and discharge it in time, so as to realize the slag is cleaned as it is produced, avoiding accumulation, decay and odor inside the equipment, keeping the inside of the equipment clean and reducing the frequency of manual cleaning.

[0024] In this embodiment, the slag discharge mechanism 11 is installed inside the upper part of the mesh drum 7. The slag baffle 112 can continuously scrape the floating slag attached to the mesh surface and send it into the slag collection tank 111, and discharge it uniformly through the slag discharge pipe 113, so as to realize the simultaneous generation and cleaning of floating slag, avoid the accumulation and decay of impurities, and keep the equipment clean.

[0025] In embodiment 3, the venturi tube 3 includes an inlet 14, an outlet 15, and an acceleration port 16. The inlet 14 is fixedly connected to the outer wall of one end of the wastewater inlet pipe 2 via a flange. The outlet 15 is fixedly connected to the outer wall of one of the mounting brackets 13 via a flange. The acceleration port 16 is welded between the inlet 14 and the outlet 15. The axial flow impeller 5 is located inside the acceleration port 16. A filter screen 17 is installed at one end of the shaft tube 4 near the axial flow impeller 5. A scraper 18 is fixedly connected to the inner wall of the acceleration port 16 of the venturi tube 3. The scraper 18 is tightly attached to one side of the outer wall of the filter screen 17.

[0026] Through the above scheme, the acceleration port 16 of the Venturi tube 3 reduces the cross-section of the water flow, significantly increasing the local flow velocity. The high-speed water flow stably impacts the axial flow impeller 5 and provides continuous rotational torque, providing reliable self-rotation power for the equipment. The filter screen 17 can perform preliminary filtration of the water flow entering the axial tube 4, intercepting large particles of impurities and avoiding clogging of the flushing nozzle 10. The scraper 18 rotates relative to the filter screen 17, which can continuously scrape off the adhering substances on the surface of the filter screen, preventing the filter screen 17 from clogging, ensuring a stable and smooth backwash water source, and creating favorable conditions for subsequent screening and denitrification reactions.

[0027] In this embodiment, the venturi tube 3, together with the filter screen 17 and the scraper 18, can filter the wastewater while accelerating its flow. The scraper 18 automatically cleans impurities from the surface of the filter screen 17, preventing the filter screen 17 from clogging and ensuring stable backwashing of the flushing nozzle 10, thus providing favorable conditions for subsequent screening and denitrification reactions.

[0028] The spindle tube 4 is installed through the inner spindle of the mesh drum 7, and the flushing nozzle 10 is located above the mesh drum 7.

[0029] With the above scheme, the shaft tube 4 serves as the overall rotation center, ensuring that the mesh drum 7 has high concentricity, smooth rotation, and low vibration during operation. The flushing nozzles 10 are evenly arranged along the axial direction of the mesh drum 7 and located directly above the mesh surface, enabling them to fully cover and evenly flush the mesh surface during rotation, resulting in good unblocking effect, long-term unobstructed mesh openings, and stable water flow.

[0030] The inner walls of the sewage tank 1 are welded with symmetrically distributed crossbeams 12, and the outer wall of the top of the crossbeams 12 is welded with mounting brackets 13. The spindle 4 is rotatably connected between the two mounting brackets 13 through bearings.

[0031] Through the above scheme, the crossbeam 12 is firmly connected to the inner wall of the sewage tank 1, providing stable support for the mounting frame 13. The mounting frame 13 adopts a symmetrical structure and supports the shaft tube 4 through bearings, which can effectively reduce rotational friction resistance, ensure that the mesh drum 7 rotates flexibly, and improve the equipment's operational stability and service life.

[0032] A water-blocking and dispersing disc 19 is welded to the outer wall of the shaft tube 4 on the side near the Venturi tube 3, and axially distributed dispersing strips 20 are provided on one side of the outer wall of the water-blocking and dispersing disc 19. The water-blocking and dispersing disc 19 is located inside the mesh drum 7.

[0033] Through the above scheme, the water-blocking and dispersing disc 19 can block the high-speed water flow from directly impacting the mesh surface, avoiding water flow scouring that causes mesh surface deformation or local blockage. The dispersing strip 20 evenly disperses the water flow along the axial direction to each area of ​​the mesh drum 7, prolonging the residence time of sewage in the mesh, allowing the carbon source and sewage to fully mix and contact, and improving the enhanced denitrification effect.

[0034] The bottom inner wall of the sewage tank 1 is covered with a gravel layer 21, and the top inner wall of the gravel layer 21 is covered with a quartz sand filter layer 22.

[0035] Through the above scheme, the gravel layer 21 plays a supporting and water distribution role, while the quartz sand filter layer 22 can deeply purify the effluent after screening, further remove tiny suspended particles and colloidal impurities, reduce the concentration of suspended solids in the effluent, improve the effluent water quality, provide more stable water quality conditions for subsequent denitrification reaction, and improve the overall denitrification efficiency of the system.

[0036] The top of each of the two mounting brackets 13 is welded with a fixing plate 23, and the backwash pipe 9 is installed between the two fixing plates 23. The inner wall of the top of the other mounting bracket 13 is fixedly connected with a clamp 24 by screws, and the slag discharge pipe 113 is installed through the inner wall of the clamp 24.

[0037] Through the above scheme, the fixing plate 23 positions and fixes the backwash pipe 9 to prevent shaking or displacement during operation, ensuring accurate and reliable flushing position. The clamp 24 adopts a detachable structure to firmly fix the slag discharge pipe 113 to prevent it from falling off or shifting, ensuring that the slag can be discharged continuously and smoothly.

[0038] A valve 25 is installed on the outer wall of the water inlet pipe 8.

[0039] With the above solution, valve 25 controls the opening and closing of the backwash water path, and can flexibly open or close the backwash according to the blockage of the mesh drum 7, adjust the flushing intensity, and make it more flexible and energy-saving.

[0040] Working principle: This equipment utilizes the wastewater's own flow to achieve automatic screening, rotation, backwashing, and slag discharge in one integrated operation. The wastewater to be treated enters the Venturi tube 3 through the wastewater inlet pipe 2. At the acceleration port 16, the flow velocity is increased, impacting the axial flow impeller 5 and causing it to rotate at high speed. This drives the shaft tube 4 and the mesh drum 7 to rotate synchronously. The wastewater enters the mesh drum 7 on one hand and flows into the shaft tube 4 after being filtered by the filter screen 17 on the other. The scraper 18 moves relative to the filter screen 17 to automatically clean the impurities on the surface of the filter screen 17, ensuring smooth water flow inside the shaft tube 4. When the sewage comes into contact with the water-blocking and dispersing disc 19, the water-blocking and dispersing disc 19 and the dispersing strip 20 will spread the water evenly. The mesh drum 7 will perform solid-liquid screening on the sewage. The clean water will enter the sewage tank 1 through the mesh and be deeply purified through the gravel layer 21 and the quartz sand filter layer 22. When the mesh drum 7 rotates, valve 25 is opened, and clean water enters the backwash pipe 9 through the shaft pipe 4 and water inlet pipe 8. It is then sprayed downwards by the flushing nozzle 10 to continuously backwash the rotating mesh drum 7, preventing the mesh from clogging. The baffle plate 112 on the top of the inner wall of the mesh drum 7 will continuously scrape the floating scum on the mesh surface and send it into the scum collection tank 111, which is then automatically discharged through the scum discharge pipe 113. The entire process does not require external power or manual retrieval, and automatically completes screening, purification, scum removal, and backwashing, solving the problems of difficult-to-clean floating scum and easy-to-clog filter screen, and ensuring the stable and efficient operation of the enhanced denitrification system. The equipment forms a closed-loop workflow during continuous operation: water intake → acceleration drive → rotary screening → uniform water distribution → backwashing to clear blockages → slag scraping and discharge → deep filtration. Each link works in concert without interfering with the others, allowing for 24-hour uninterrupted operation. The mesh drum 7 is not prone to clogging, scum does not accumulate, and carbon source is fully mixed, significantly improving the treatment efficiency and stability of the enhanced denitrification system and reducing maintenance workload and operating costs.

[0041] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A carbon source screening device for enhanced denitrification in wastewater treatment, comprising a wastewater tank (1), characterized in that, Wastewater inlet pipe (2) is installed through one side of the outer wall of the sewage tank (1), and a venturi pipe (3) is fixedly connected to one end of the outer wall of the wastewater inlet pipe (2) by a flange. A mesh drum (7) is provided on one end of the outer wall of the venturi pipe (3), and a self-rotating backwash mechanism is provided inside the venturi pipe (3) and the mesh drum (7). The self-rotating backwash mechanism includes a core tube (4), an axial flow impeller (5), a connecting rod (6), a water inlet pipe (8), a backwash pipe (9), and a flushing nozzle (10). The connecting rod (6) is welded to the inner walls of both ends of the mesh drum (7). The core tube (4) is welded between two sets of connecting rods (6). The axial flow impeller (5) is installed on the outer wall of the core tube (4). A rotary joint is installed at the end of the core tube (4) away from the axial flow impeller (5). The water inlet pipe (8) is rotatably connected to the outer wall of one end of the core tube (4) through the rotary joint. The backwash pipe (9) is fixedly connected to the outer wall of one end of the water inlet pipe (8). The flushing nozzles (10) distributed in an array are installed on the bottom outer wall of the backwash pipe (9). A slag discharge mechanism (11) is provided on the top inner wall of the mesh drum (7).

2. The carbon source screening equipment for enhanced denitrification in wastewater treatment according to claim 1, characterized in that, The slag discharge mechanism (11) includes a slag collection trough (111), a slag baffle plate (112), and a slag discharge pipe (113). The slag collection trough (111) is located on the top of the inner wall of the mesh drum (7). The slag baffle plate (112) is welded to the inner wall of the slag collection trough (111) and is tightly attached to the top inner wall of the mesh drum (7). The slag discharge pipe (113) is fixedly installed on the outer wall of one end of the slag collection trough (111).

3. The carbon source screening equipment for enhanced denitrification in wastewater treatment according to claim 1, characterized in that, The spindle tube (4) is installed through the inner spindle of the mesh drum (7), and the flushing nozzle (10) is located above the mesh drum (7).

4. The carbon source screening equipment for enhanced denitrification in wastewater treatment according to claim 1, characterized in that, The sewage tank (1) has symmetrically distributed crossbeams (12) welded on the inner walls of both sides, and a mounting frame (13) is welded on the outer wall of the top of the crossbeam (12). The shaft tube (4) is rotatably connected between the two mounting frames (13) through a bearing.

5. A carbon source screening device for enhanced denitrification in wastewater treatment according to claim 1, characterized in that, The Venturi tube (3) includes an inlet (14), a drain (15), and an acceleration port (16). The inlet (14) is fixedly connected to the outer wall of one end of the wastewater inlet pipe (2) by a flange. The drain (15) is fixedly connected to the outer wall of one of the mounting brackets (13) by a flange. The acceleration port (16) is welded between the inlet (14) and the drain (15). The axial flow impeller (5) is located inside the acceleration port (16).

6. A carbon source screening device for enhanced denitrification in wastewater treatment according to claim 1, characterized in that, A filter screen (17) is installed at one end of the shaft tube (4) near the axial flow impeller (5), and a scraper (18) is fixedly connected to the inner wall of the acceleration port (16) of the venturi tube (3), the scraper (18) being tightly attached to one side of the outer wall of the filter screen (17).

7. A carbon source screening device for enhanced denitrification in wastewater treatment according to claim 1, characterized in that, A water-blocking and dispersing disc (19) is welded on the outer wall of the core tube (4) near the venturi tube (3), and axially distributed dispersing strips (20) are provided on the outer wall of one side of the water-blocking and dispersing disc (19). The water-blocking and dispersing disc (19) is located inside the mesh drum (7).

8. A carbon source screening device for enhanced denitrification in wastewater treatment according to claim 1, characterized in that, The bottom inner wall of the sewage tank (1) is covered with a gravel layer (21), and the top inner wall of the gravel layer (21) is covered with a quartz sand filter layer (22).

9. A carbon source screening device for enhanced denitrification in wastewater treatment according to claim 4, characterized in that, The top of each of the two mounting brackets (13) is welded with a fixing plate (23), and the backwash pipe (9) is installed between the two fixing plates (23). The inner wall of the top of the other mounting bracket (13) is fixedly connected with a clamp (24) by screws, and the slag discharge pipe (113) is installed on the inner wall of the clamp (24).

10. A carbon source screening device for enhanced denitrification in wastewater treatment according to claim 1, characterized in that, A valve (25) is installed on the outer wall of the water inlet pipe (8).

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