Efficient fluidized bed denitrification nitrogen removal tower

Abstract

The utility model discloses an efficient fluidized bed denitrification nitrogen removal tower which comprises a tower body, a water distribution pipe, a water inlet pump, a backflow water pipe and a backflow circulating pump, a fluidization reaction area, a backflow buffer area and a water outlet area are formed in the tower body from bottom to top, and a plurality of lower-layer inclined plates which are arranged in parallel at intervals are fixedly arranged between the backflow buffer area and the fluidization reaction area. A plurality of upper-layer inclined plates which are arranged in parallel at intervals are fixedly arranged between the backflow buffer area and the water outlet area, water passing channels which obliquely extend are formed between the adjacent lower-layer inclined plates and between the adjacent upper-layer inclined plates respectively, a water outlet pipe opening is formed in the side wall of the water outlet area, and a water inlet pump can feed water to be treated into the tower body through a water distribution pipe fixedly arranged at the lower end in the tower body. The side wall of the backflow buffer area is provided with a backflow port, the two ends of the backflow water pipe are communicated with the backflow port and the water distribution pipe, and the backflow circulating pump can pump water and sludge in the backflow buffer area into the water distribution pipe, so that the sludge leakage caused by the ascending velocity is reduced, the sludge amount and the denitrification load in the reactor are ensured, and the device is energy-saving and environment-friendly.

Description

Technical Field

[0001] The utility model relates to a wastewater treatment technology, in particular to a high-efficiency fluidized bed denitrification tower. Background Art

[0002] Conventional denitrification reactors are mainly based on AO, but there are some industries that use a large amount of HNO3, such as stainless steel acid and fluorine chemical industries. The concentration of nitrate nitrogen in their wastewater is as high as thousands, and the volume is large. The conventional AO pool occupies a large area and the treatment cost is also high.

[0003] In response to high-concentration, high-volume nitrate nitrogen wastewater, environmental protection companies have developed tower-type denitrification reactors. By increasing the sludge concentration in the reactor, the sludge (bacteria) is fully contacted with the nitrate nitrogen in the wastewater in the form of a fluidized bed, the treatment load per unit area is increased, and the reactor footprint is reduced, achieving certain breakthroughs. Since the rising velocity in the fluidized bed is relatively high, generally above 4m / h, and the denitrification process itself produces a large amount of nitrogen, the fluidized bed reactor has a large scouring amplitude on the sludge, which is very likely to cause sludge loss and a decrease in the denitrification load. Therefore, the fluidized bed denitrification reactor has relatively high requirements for the stability of the sludge.

[0004] At present, the commonly used method to maintain sludge stability in fluidized beds is to add fillers or carriers, such as activated carbon, quartz sand, polymer suspension fillers, granular sludge, etc., so that the sludge or bacteria are attached to the fillers / carriers, and the weight of the fillers or carriers is used to increase the rising flow rate of the fluidized bed and the scouring of nitrogen produced by denitrification, thereby maintaining the stability of the sludge in the denitrification tower.

[0005] However, the circulation recirculation port of the existing fluidized bed denitrification tower is near the water outlet or shared with the water outlet, which causes the rising flow velocity in the water outlet area to be consistent with the rising flow velocity in the denitrification reaction area. When a large amount of gas gathers in one place in the reactor, causing a sudden increase in instantaneous impulse or the system is unstable, causing the properties of the sludge itself to weaken, it is very easy for the sludge to be carried to the water outlet area, resulting in sludge leakage. Utility Model Content

[0006] In order to overcome the above defects, the utility model provides a high-efficiency fluidized bed denitrification tower, which can effectively reduce the occurrence of mud leakage in the outlet area, ensure the effective denitrification reaction, and save energy and protect the environment.

[0007] The utility model adopts a technical solution to solve the technical problem: a high-efficiency fluidized bed denitrification tower, comprising a tower body, a water distribution pipe, a water inlet pump, a reflux water pipe and a reflux circulation pump, wherein the lower section of the tower body forms a fluidized reaction zone, the water distribution pipe is fixedly arranged in the lower end of the tower body, the water inlet pump can send the water to be treated into the tower body through the water distribution pipe, the upper end of the tower body forms a water outlet zone, the side wall of the water outlet zone is provided with a water outlet pipe port, the water outlet end of the reflux water pipe is connected with the water distribution pipe, a reflux buffer zone is also provided in the tower body, and the reflux buffer zone is provided in the tower body. The flushing zone is located between the fluidized reaction zone and the water outlet zone, a number of lower inclined plates arranged in parallel and spaced apart are fixedly provided between the reflux buffer zone and the fluidized reaction zone, a number of upper inclined plates arranged in parallel and spaced apart are fixedly provided between the reflux buffer zone and the water outlet zone, and inclined and extended water passages are formed between adjacent lower inclined plates and adjacent upper inclined plates, a reflux port is provided on the side wall of the tower body located in the reflux buffer zone, the water inlet end of the reflux water pipe is connected to the reflux port, and the reflux circulation pump can pump the water and mud in the reflux buffer zone into the water distribution pipe.

[0008] As a further improvement of the utility model, a first aeration flushing pipe is fixedly provided below the lower inclined plate, and a second aeration flushing pipe is fixedly provided below the upper inclined plate. The first aeration flushing pipe and the second aeration flushing pipe can perform aeration backwashing on the lower inclined plate and the upper inclined plate respectively.

[0009] As a further improvement of the utility model, the first aeration flushing pipe and the second aeration flushing pipe each include a cross-shaped aeration main pipe and a plurality of circular aeration branch pipes, the plurality of aeration branch pipes are arranged at different intervals with the cross-shaped center of the aeration main pipe as the center of the circle, the plurality of aeration branch pipes are evenly cross-connected with the aeration main pipe, and a plurality of aeration flushing holes are evenly spaced on each aeration branch pipe.

[0010] As a further improvement of the utility model, a water outlet weir is fixedly provided in the water outlet area, the water outlet pipe port is arranged in the water outlet weir of the water outlet area, and a sedimentation water outlet area is formed between the lower part of the water outlet weir and the upper inclined plate.

[0011] As a further improvement of the utility model, a spray pipe is fixedly provided on the tower body above the water outlet area, and the spray pipe can spray clean water onto the water surface of the water outlet area to eliminate foam on the water surface of the water outlet area.

[0012] As a further improvement of the utility model, the spray pipe includes a spray main pipe and a spray branch pipe, a plurality of spray branch pipes are arranged at intervals along the length direction of the spray main pipe, the spray branch pipes are arranged perpendicularly to the spray main pipe, the spray main pipe and the spray branch pipes are connected at the intersection, a blocking structure is formed at the end of the spray main pipe, and a plurality of spray openings are evenly spaced on each spray branch pipe.

[0013] As a further improvement of the present invention, the inclination angle range of the upper inclined plate and the lower inclined plate is 55° to 60°, the height of the upper inclined plate is 400-500mm, and the plate spacing of the upper inclined plate is 30-40mm; the height of the lower inclined plate is 400-500mm, and the plate spacing of the lower inclined plate is 60-80mm.

[0014] As a further improvement of the present utility model, the water distribution pipe includes an upper water distribution pipe and a lower water distribution pipe, and the projections of the upper water distribution pipe and the lower water distribution pipe on the horizontal plane have a horizontal intersection angle, and the horizontal intersection angle of the upper water distribution pipe and the lower water distribution pipe is 20°~30°. The upper water distribution pipe and the lower water distribution pipe both include a water distribution main pipe and a water distribution branch pipe, and a plurality of water distribution branch pipes are arranged at intervals along the length direction of the water distribution main pipe, and the water distribution branch pipes are arranged vertically and crosswise with the water distribution main pipe, and the intersection of the water distribution main pipe and the water distribution branch pipe is connected, the length of the water distribution branch pipe located in the middle part of the water distribution main pipe is greater than the length of the water distribution branch pipe located at both ends of the water distribution main pipe, and the middle part of the upper water distribution main pipe and the lower water distribution main pipe is arranged directly opposite to each other in the up and down directions.

[0015] As a further improvement of the utility model, a plurality of sampling ports that can be opened and closed are arranged at intervals on the side wall of the tower body, and each sampling port is respectively connected to the lower end of the reaction zone, the upper end of the reaction zone and the reflux buffer zone inside the tower body.

[0016] As a further improvement of the utility model, a mud discharge port which can be opened and closed is provided at the lower end of the tower body.

[0017] The beneficial effects of the utility model are as follows: the utility model forms a reflux buffer zone between the upper sloping plate and the lower sloping plate by fixing the upper sloping plate and the lower sloping plate in the tower body, designs the reflux port at the location of the reflux buffer zone, and blocks the reflux buffer zone and the water outlet zone by the upper sloping plate, so that the reflux port is far away from the water outlet zone, and blocks the reflux buffer zone and the reaction zone by the lower sloping plate, so that the muddy water is not affected by the rising flow velocity in the area above the reflux port, thereby reducing the hydraulic disturbance caused by the rising flow velocity in the water outlet zone, and controlling the muddy water in the reflux port. When it reaches the upper inclined plate, there is basically only the flow rate brought by the incoming water, which effectively intercepts the sludge and reduces the sludge running caused by the rising flow rate. The reflux port of the utility model cooperates with the upper inclined plate so that the sludge blocked by the upper inclined plate can return to the bottom of the reactor from the reflux port, ensuring the sludge amount and denitrification load in the reactor. The utility model also installs a spray pipe on the top of the tower body, which sprays the water surface of the outlet area, thereby eliminating the foam floating on the water surface of the outlet area, effectively reducing the foam floating out of the tower, avoiding the foam from polluting the atmosphere, and being more conducive to environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structural principle of the utility model;

[0019] Figure 2 This is a large-scale drawing of the water distribution pipe of the utility model;

[0020] Figure 3 This is a large-scale drawing of the aeration pipeline of the utility model;

[0021] Figure 4 This is a large-scale drawing of the spray pipe of the utility model. DETAILED DESCRIPTION

[0022] Embodiment: A high-efficiency fluidized bed denitrification tower, comprising a tower body, a water distribution pipe, a water inlet pump 15, a reflux water pipe 16 and a reflux circulation pump 17, wherein the lower section of the tower body forms a fluidized reaction zone 1, the water distribution pipe is fixedly arranged in the lower end of the tower body, the water inlet pump 15 can send the water to be treated into the tower body through the water distribution pipe, the upper end of the tower body forms a water outlet zone, the side wall of the water outlet zone is provided with a water outlet pipe 9, the water outlet end of the reflux water pipe 16 is connected to the water distribution pipe, and the tower body is also provided with a reflux buffer zone 2, which is located in the fluidized reaction zone 1 and the water outlet area, a plurality of lower inclined plates 4 arranged in parallel and spaced apart are fixedly provided between the reflux buffer area 2 and the fluidized reaction area 1, a plurality of upper inclined plates 5 arranged in parallel and spaced apart are fixedly provided between the reflux buffer area 2 and the water outlet area, and inclined and extended water passages are formed between adjacent lower inclined plates 4 and adjacent upper inclined plates 5, respectively, a reflux port 8 is provided on the side wall of the tower body located in the reflux buffer area 2, the water inlet end of the reflux water pipe 16 is connected to the reflux port 8, and the reflux circulation pump 17 can pump the water and mud in the reflux buffer area 2 into the water distribution pipe.

[0023] The wastewater entering the tower body rises into the reflux buffer zone 2 after contacting and reacting with the sludge in the fluidized reaction zone 1. The lower inclined plate 4 between the fluidized reaction zone 1 and the reflux buffer zone 2 is used to intercept the sludge in the wastewater flowing from the fluidized reaction zone 1 to the reflux buffer zone 2. The sludge is blocked by the lower inclined plate 4 and sinks back into the fluidized reaction zone 1. When the muddy water rises to a position above the reflux port 8, it is no longer affected by the circulating water flow rate, and the rising flow rate of the muddy water begins to gradually decrease to the rising flow rate brought by the water intake alone. When the muddy water reaches the upper inclined plate 5, there is basically no large rising force. Most of the floating sludge in the muddy water is blocked by the upper inclined plate 5 and stays in the reflux buffer zone 2. As the reflux water flows back to the lower end of the tower, it finally returns to the fluidized reaction zone 1 to participate in the reaction. The fluidized bed denitrification and denitrification tower with the above structure can effectively reduce the sludge running caused by the rising flow rate. The muddy water is blocked by the lower inclined plate 4 and the upper inclined plate 5 to fully realize the sludge retention, thereby ensuring the sludge amount and denitrification load in the reactor.

[0024] A first aeration flushing pipe 12 is fixedly provided below the lower inclined plate 4, and a second aeration flushing pipe 13 is fixedly provided below the upper inclined plate 5. The first aeration flushing pipe 12 and the second aeration flushing pipe 13 can respectively perform aeration backwashing on the lower inclined plate 4 and the upper inclined plate 5. By respectively providing the first aeration flushing pipe 12 and the second aeration flushing pipe 13 below the lower inclined plate 4 and the upper inclined plate 5, the first aeration flushing pipe 12 and the second aeration flushing pipe 13 perform regular backwashing on the lower inclined plate 4 and the upper inclined plate 5, thereby preventing the lower inclined plate 4 and the upper inclined plate 5 from being damaged due to sludge accumulation.

[0025] The first aeration flushing pipe 12 and the second aeration flushing pipe 13 each include a cross-shaped aeration main pipe 121 and a plurality of circular aeration branch pipes 122. The plurality of aeration branch pipes 122 are arranged at intervals in different directions with the cross-shaped center of the aeration main pipe 121 as the center of the circle. Each aeration branch pipe 122 is evenly cross-connected with the aeration main pipe 121, and a plurality of aeration flushing holes 123 are evenly spaced on each aeration branch pipe 122. The first aeration flushing pipe 12 and the second aeration flushing pipe 13 are arranged in a circular shape to ensure the uniformity of flushing. The diameter of the aeration branch pipe 122 is DN25 or DN32, and the aeration flushing hole 123 can be designed according to the large resistance water distribution system. The flushing time is controlled by a time controller or a time program.

[0026] The outlet weir 6 is fixedly provided in the outlet area, and the outlet pipe 9 is provided in the outlet weir 6 of the outlet area, and a sedimentation outlet area 3 is formed between the lower part of the outlet weir 6 and the upper inclined plate 5. The effluent after the reaction in the tower enters the outlet weir 6 and is discharged through the outlet pipe 9, and a very small amount of sludge entering the outlet area sinks in the sedimentation outlet area 3 and finally enters the reflux buffer area 2.

[0027] The tower body is fixedly provided with a spray pipe 14 above the water outlet area, and the spray pipe 14 can spray clean water toward the water surface of the water outlet area to eliminate the foam on the water surface of the water outlet area. During the denitrification reaction, there will be a lot of foam on the water surface at the top of the tower. By regularly opening the water spray, the spray pipe 14 is sprayed toward the water surface of the water outlet area to eliminate the foam on the water surface at the top of the tower, so as to prevent the foam from floating into the atmosphere and causing pollution.

[0028] The spray pipe 14 includes a spray main pipe 141 and a spray branch pipe 142. A plurality of spray branch pipes 142 are arranged at intervals along the length direction of the spray main pipe 141. The spray branch pipes 142 and the spray main pipe 141 are arranged vertically and crosswise. The spray main pipe 141 and the spray branch pipes 142 are connected at the intersection. The end of the spray main pipe 141 forms a blocking structure. A plurality of spray ports 143 are evenly spaced on each spray branch pipe 142. The end of the spray main pipe 141 of the spray pipe 14 is blocked, and water flows out from each spray port 143 on the spray branch pipe 142. The size of the spray port 143 can be designed according to the large resistance water distribution system.

[0029] The inclination angle range of the upper inclined plate 5 and the lower inclined plate 4 is 55°

[0030] ~60°, the height of the upper inclined plate 5 is 400-500mm, and the plate spacing of the upper inclined plate 5 is 30-40mm; the height of the lower inclined plate 4 is 400-500mm, and the plate spacing of the lower inclined plate 4 is 60-80mm. Since the reflux port 8 is below the upper inclined plate 5, there is no need to consider the influence of the rising flow velocity, so the spacing of the upper inclined plate is smaller than that of the lower inclined plate 4, and the sludge interception effect is better.

[0031] The water distribution pipe includes an upper water distribution pipe 71 and a lower water distribution pipe 72. The projections of the upper water distribution pipe 71 and the lower water distribution pipe 72 on the horizontal plane have a horizontal intersection angle b. The horizontal intersection angle of the upper water distribution pipe 71 and the lower water distribution pipe 72 is 20° to 30°. The upper water distribution pipe 71 and the lower water distribution pipe 72 both include a water distribution main pipe 711 and a water distribution branch pipe 712. A plurality of water distribution branch pipes 712 are arranged at intervals along the length direction of the water distribution main pipe 711. The water distribution branch pipes 712 are arranged to cross the water distribution main pipe 711 vertically. The intersection of the water distribution main pipe 711 and the water distribution branch pipes 712 is connected. The length of the water distribution branch pipe 712 located in the middle part of the water distribution main pipe 711 is greater than the length of the water distribution branch pipe 712 located at both ends of the water distribution main pipe 711, and the middle parts of the upper water distribution main pipe 711 and the lower water distribution main pipe 711 are arranged directly opposite to each other in the up and down directions. The water distribution pipes are divided into two layers, the upper and lower layers. The two layers of water distribution pipes cross horizontally to ensure uniform water distribution and improve reaction efficiency. The water distribution holes are designed according to the large resistance water distribution system.

[0032] The side wall of the tower body is provided with a plurality of sampling ports 11 which can be opened and closed, and each sampling port 11 is respectively connected with the lower end of the reaction zone, the upper end of the reaction zone and the reflux buffer zone 2 inside the tower body. Each sampling port 11 is used to sample different heights of the fluidized bed, so as to understand the sludge stratification in the tower and ensure the sludge amount and reaction stability in the tower.

[0033] The lower end of the tower body is provided with a mud discharge vent 10 which can be opened and closed. The mud discharge vent 10 can be used for mud discharge and also used as a vent for tower body maintenance.

Claims

1. A high-efficiency fluidized bed denitrification tower, comprising a tower body, a water distribution pipe, a water inlet pump (15), a reflux water pipe (16) and a reflux circulation pump (17), wherein the lower section of the tower body forms a fluidized reaction zone (1), the water distribution pipe is fixedly arranged in the lower end of the tower body, the water inlet pump can deliver the water to be treated into the tower body through the water distribution pipe, the upper end of the tower body forms a water outlet zone, the side wall of the water outlet zone is provided with a water outlet pipe port (9), the water outlet end of the reflux water pipe is connected to the water distribution pipe, and the characteristics are: A reflux buffer zone (2) is also provided inside the tower body. The reflux buffer zone is located between the fluidized reaction zone and the water outlet zone. A plurality of lower inclined plates (4) arranged in parallel and spaced apart are fixedly provided between the reflux buffer zone and the fluidized reaction zone. A plurality of upper inclined plates (5) arranged in parallel and spaced apart are fixedly provided between the reflux buffer zone and the water outlet zone. Inclined and extending water passages are formed between adjacent lower inclined plates and adjacent upper inclined plates. A reflux port (8) is provided on the side wall of the tower body located in the reflux buffer zone. The water inlet end of the reflux water pipe is connected to the reflux port. The reflux circulation pump can pump water and mud in the reflux buffer zone into the water distribution pipe.

2. The high-efficiency fluidized bed denitrification tower according to claim 1, characterized in that: A first aeration and flushing pipe (12) is fixedly provided below the lower inclined plate, and a second aeration and flushing pipe (13) is fixedly provided below the upper inclined plate. The first aeration and flushing pipe and the second aeration and flushing pipe can respectively perform aeration backwashing on the lower inclined plate and the upper inclined plate.

3. The high-efficiency fluidized bed denitrification tower according to claim 2, characterized in that: The first aeration flushing pipe and the second aeration flushing pipe both comprise a cross-shaped aeration main pipe (121) and a plurality of circular aeration branch pipes (122), wherein the plurality of aeration branch pipes are arranged at intervals in different directions with the cross-shaped center of the aeration main pipe as the center of the circle, and each aeration branch pipe is evenly cross-connected with the aeration main pipe, and each aeration branch pipe is evenly spaced and provided with a plurality of aeration flushing holes (123).

4. The high-efficiency fluidized bed denitrification tower according to claim 1, characterized in that: A water outlet weir (6) is fixedly arranged in the water outlet area, the water outlet pipe opening is arranged in the water outlet weir of the water outlet area, and a sedimentation water outlet area (3) is formed between the lower part of the water outlet weir and the upper inclined plate.

5. The high-efficiency fluidized bed denitrification tower according to claim 1, characterized in that: The tower body is fixedly provided with a spray pipe (14) above the water outlet area, and the spray pipe can spray clean water toward the water surface of the water outlet area to eliminate foam on the water surface of the water outlet area.

6. The high-efficiency fluidized bed denitrification tower according to claim 5, characterized in that: The spray pipe comprises a spray main pipe (141) and a spray branch pipe (142), wherein a plurality of spray branch pipes are arranged at intervals along the length direction of the spray main pipe, the spray branch pipes are arranged perpendicularly to the spray main pipe, the spray main pipe and the spray branch pipes are connected at their intersections, a blocking structure is formed at the end of the spray main pipe, and a plurality of spray ports (143) are evenly spaced on each spray branch pipe.

7. The high-efficiency fluidized bed denitrification tower according to claim 1, characterized in that: The inclination angles of the upper and lower inclined plates range from 55° to 60°, the height of the upper inclined plate is 400-500mm, and the plate spacing of the upper inclined plate is 30-40mm; the height of the lower inclined plate is 400-500mm, and the plate spacing of the lower inclined plate is 60-80mm.

8. The high-efficiency fluidized bed denitrification tower according to claim 1 or 7, characterized in that: The water distribution pipe comprises an upper water distribution pipe (71) and a lower water distribution pipe (72). The projections of the upper water distribution pipe and the lower water distribution pipe on the horizontal plane have a horizontal intersection angle (b). The horizontal intersection angle of the upper water distribution pipe and the lower water distribution pipe is 20° to 30°. The upper water distribution pipe and the lower water distribution pipe both comprise a water distribution main pipe (711) and a water distribution branch pipe (712). A plurality of water distribution branch pipes are arranged at intervals along the length direction of the water distribution main pipe. The water distribution branch pipes are arranged to cross the water distribution main pipe vertically. The water distribution main pipe and the water distribution branch pipe intersection are connected. The length of the water distribution branch pipe located in the middle of the water distribution main pipe is greater than the length of the water distribution branch pipes located at both ends of the water distribution main pipe. The middle of the upper water distribution main pipe and the lower water distribution main pipe are arranged to face each other in the up-down direction.

9. The high-efficiency fluidized bed denitrification tower according to claim 1, characterized in that: A plurality of sampling ports (11) capable of being opened and closed are arranged at intervals on the side wall of the tower body, and each sampling port is respectively connected to the lower end of the reaction zone, the upper end of the reaction zone and the reflux buffer zone inside the tower body.

10. The high-efficiency fluidized bed denitrification tower according to claim 1, characterized in that: The lower end of the tower body is provided with a mud discharge port (10) which can be opened and closed.

Images