CN217555892U

CN217555892U - Deep bed filter of denitrification of back flush intake pipe installation of burying end

Info

Publication number: CN217555892U
Application number: CN202221307792.3U
Authority: CN
Inventors: 蒋懿敏; 张德顺; 陈栋; 满宜江
Original assignee: Suzhou Zhenyu Environmental Protection Technology Co ltd
Current assignee: Suzhou Zhenyu Environmental Protection Technology Co ltd
Priority date: 2022-05-26
Filing date: 2022-05-26
Publication date: 2022-10-11
Anticipated expiration: 2032-05-26

Abstract

The utility model discloses a deep bed filter of denitrification of back flush intake pipe installation of burying end, including cell body, piping lane within a definite time, a plurality of precoat, a plurality of back flush trachea. The backwashing gas distribution square pipe is provided with a backwashing gas branch pipe, one end of the backwashing gas inlet main pipe is communicated with the backwashing gas distribution square pipe, and the other end of the backwashing gas inlet main pipe extends into the pipe gallery; the bottom of the pool has still seted up the water catch bowl, and the water catch bowl is connected with the outlet pipe, and the top of partition wall is equipped with the canal that catchments, through the spillway hole intercommunication between canal and the filtering pond, the canal connection has the collector pipe, and the collector pipe all extends to the piping lane within a definite time and connects and be equipped with the diverter valve in junction between them with the outlet pipe, still is equipped with on the outlet pipe with water through in the outlet pipe flow direction water catch bowl and the upflow in order to carry out the backwash pump of water distribution backwash to the precoat. The problem of prior art take place about easily to flow, influence the backwash effect and influence the outward appearance image is solved.

Description

Deep bed filtering pond of denitrification of installation is buried at end to back flush intake pipe

Technical Field

The utility model relates to the technical field of environmental protection, concretely relates to back flush intake pipe buries deep bed filtering pond of denitrification of end installation.

Background

With the improvement of the national discharge standard of sewage treatment plants, in order to reach the national discharge standard of pollutants for municipal sewage treatment plants, the standards of a plurality of sewage treatment plants in China are upgraded from the first-class B to the first-class A. The denitrification deep-bed filter tank has the function of synchronously removing total nitrogen, suspended matters and total phosphorus, and can effectively improve the discharge standard from a first level B to a first level A, so that the denitrification deep-bed filter tank is favored by various manufacturers and design houses.

The working principle of the denitrification deep bed filter is that nitrate nitrogen is converted into nitrogen by denitrifying bacteria attached to and growing on the surface of quartz sand by utilizing a carbon source in water to complete a denitrification reaction process, and the total nitrogen in sewage is removed. In the denitrification process, as nitrate nitrogen is continuously reduced into nitrogen, a large amount of nitrogen is gradually gathered in the deep bed filter, on one hand, the nitrogen can cause sewage to flow around media, the contact between microorganisms and water flow is increased, and the filtering efficiency is improved. However, when too many nitrogen bubbles are accumulated in the filter, head loss is caused, and when suspended matters or propagating microorganisms are trapped in the filter material layer to a certain degree, the filter layer needs to be backwashed regularly, during backwashing, water and gas are distributed uniformly through the gas distribution pipe and the water distribution pipe, and upward force is generated by the water and the gas to disperse the nitrogen bubbles out of the filter and flush the trapped suspended matters or propagating microorganisms in the filter material layer to recover the head.

Chinese patent CN 206666221U discloses a deep-bed denitrification filter, which comprises a filter, a main water inlet channel, a filter water distribution channel, a quartz sand layer, a filter material layer, a back-flushing water pipe and a back-flushing air pipe, wherein the inner wall of the filter is provided with the quartz sand layer, the bottom end of the filter water distribution channel is provided with a back-flushing drain pipe, the bottom end of the inside of the filter is provided with a filter brick layer, the top end of the filter brick layer is covered with the filter material layer, one end of the back-flushing air pipe extends into the space between the filter brick layer and the filter material layer along the vertical direction, and the other end of the back-flushing air pipe is connected with a back-flushing fan outside the filter. The technical scheme is that a water flow penetrates through a filter material layer to form a series flow weak part when a quartz sand layer and a smooth partition wall are combined, an air inlet main pipe is transversely arranged on the surface of a tank and is not beneficial to the appearance of the surface of the tank, and a backwashing air pipe is inserted into a backwashing air distribution pipe at the bottom of the tank from the surface of the tank and is connected with the backwashing air distribution pipe at the bottom of the tank, so that the potential hazard of the filter material layer that the filter material layer flows up and down in series is increased. Therefore, how to arrange the backflushing air pipes reasonably becomes a technical problem to be solved.

SUMMERY OF THE UTILITY MODEL

At least one of the technical problem to the aforesaid existence, the utility model aims at providing a back flush intake pipe buries the deep bed filtering pond of denitrification of end installation, has solved among the prior art back flush trachea and has increased the possibility and influence treatment effect and be unfavorable for the problem of pond face outward appearance image of series flow from top to bottom in vertical inserting the filter bed of filter material.

The technical scheme of the utility model is that:

an object of the utility model is to provide a back flush intake pipe buries deep bed filtering pond of denitrification of end installation, including the cell body, the cell body still includes including a plurality of filtering pond that the partition wall that is set up by a plurality of edge cell body length direction extensions separates:

the pipe gallery is arranged outside one end of the tank body in the length direction;

the filter material layers are correspondingly paved on the bottom surfaces of the filter tanks one by one;

the backwashing air distribution main pipes are arranged in the pipe gallery and connected with a backwashing fan;

the bottom surface of any filter pool is also provided with a water collecting tank extending along the length direction of the filter pool, one end of the water collecting tank facing the pipe gallery is connected with a water outlet pipe, the top end of the partition wall and/or the pool wall of the filter pool in the length direction is provided with a water collecting channel, the water collecting channel is communicated with the filter pool through an overflow hole, one end of the water collecting channel facing the pipe gallery is connected with a water collecting pipe, the water collecting pipe and the water outlet pipe both extend into the pipe gallery, and the water outlet pipe is connected with a backwashing pump which flows water into the water collecting tank through the water outlet pipe and flows upwards to carry out water distribution backwashing on the filter material layer.

Preferably, the backwash air inlet main pipe is connected with the corresponding backwash air distribution square pipe through an elbow;

the back-flushing air inlet main pipes of the two adjacent filter tanks are U-shaped.

Preferably, the backwash air inlet main pipe and the corresponding backwash air distribution square pipe are welded through an elbow, and a welding line has no leakage.

Preferably, when the backwashing air inlet main pipe is installed, a pipe groove is formed downwards at a position, far away from the pipe gallery, of the bottom surface of the corresponding filter tank and faces the direction between the pipe galleries;

laying the backwashing air inlet main pipe in the pipe groove and filling concrete to the bottom surface of the tank, wherein the pipe groove at the joint of the backwashing air inlet main pipe and the backwashing air distribution square pipe is not filled with concrete to reserve an operation space for welding the elbow, and after the welding is finished, filling the operation space with concrete until the operation space is level to the bottom surface of the tank.

Preferably, any one of the pipe troughs extends downwards from the central position of the length of the bottom surface of the corresponding filter tank and towards the direction between the pipe galleries.

Preferably, the side surface of any one of the backwashing air distribution square pipes is flush with and fixed to the bottom wall surface of the partition wall of the corresponding filter tank, and the bottom surface of the backwashing air distribution square pipe is flush with and fixed to the bottom surface of the corresponding filter tank.

Preferably, the connection position of the backwash air inlet main pipe and the corresponding backwash air distribution square pipe is located at the center of the length direction of the corresponding filter tank.

Preferably, the length direction of any one back-washing air distribution square pipe extends along the length direction of the corresponding filter chamber; and/or

The length center of the backwashing air distribution square pipe is superposed with the length center of the corresponding filter tank.

Preferably, an air-water distribution block layer formed by splicing a plurality of block structures is further laid at the bottom of the filter material layer, and an avoidance gap for backwashing gas and backwashing water to pass through and face the filter material layer is formed between the adjacent block structures.

Preferably, a bearing layer is further arranged between the filter material layer and the gas-water distribution block layer, the filter material layer is sand filter, and the bearing layer is pebbles.

Compared with the prior art, the utility model has the advantages that:

the utility model discloses a deep bed filtering pond of denitrification of installation is buried to back flush intake pipe, the utility model discloses a arrange back flush inlet manifold below the bottom of the pool face, solved among the prior art directly insert the filter bed and be connected the problem that leads to streaming about taking place easily and influence the problem of backwash effect with the back flush gas distribution pipe of bottom of the pool along vertical direction with back flush inlet manifold, set up between the piping lane, with back flush intake-tube connection's back flush fan and the components and parts on the pipeline and be used for the pipeline of back flush water distribution and the components and parts setting on the pipeline in the piping lane of keeping apart with the cell body, make cell body top surface outward appearance clean, solved the visual problem of influence outward appearance that leads to among the prior art.

Drawings

The invention will be further described with reference to the following drawings and examples:

FIG. 1 is a sectional view of a denitrification deep bed filter mounted with a backwash inlet pipe buried in the bottom according to an embodiment of the present invention;

FIG. 2 isbase:Sub>A schematic view ofbase:Sub>A cross-sectional structure along the direction A-A of the denitrification deep-bed filter in FIG. 1;

FIG. 3 is a sectional structure view along the direction B-B of the denitrification deep-bed filter in FIG. 1;

FIG. 4 is a schematic view of a vertical plane sectioning structure of a denitrification deep bed filter chamber installed with a backwash air inlet pipe buried at the bottom, wherein a filter material layer, a supporting layer and an air-water distribution block layer are not laid, and an operation space is not filled with water;

FIG. 5 is a schematic view of a C-C direction sectioning structure of the denitrification deep-bed filter in FIG. 4;

FIG. 6 is a D-D direction sectioning structure schematic diagram of the denitrification deep bed filter tank of FIG. 4;

FIG. 7 is a schematic diagram of a partial enlarged structure of a gas-water distribution block of the denitrification deep-bed filter in FIG. 1.

Wherein: 1. a tank body; 10. a partition wall; 11. the bottom of the pool; 2. among the pipe galleries; 31. backwashing the air inlet main pipe; 311. a pneumatic butterfly valve; 32. backwashing the gas distribution square pipe; 33. backwashing the bronchus; 34. bending the pipe; 35. an operating space; 41. a water collecting channel; 42. a water collection pipe; 43. a water collection tank; 44. a water outlet pipe; 45. an overflow hole; 46. A backwash pump; 5. a filter material layer; 6. a support layer; 7. a gas-water distribution block layer; 71. a block-like structure; 72. avoiding the gap.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings. It should be understood that the description is intended to be illustrative only and is not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.

Referring to fig. 1 to 6, a denitrification deep bed filter with a back flush air inlet pipe installed in the embodiment of the present invention includes a tank body 1, a pipe gallery 2, a plurality of filter material layers 5 and a plurality of back flush air pipes. As shown in fig. 3 and 6, the tank body 1 comprises a plurality of filter chambers, and adjacent filter chambers are separated by a partition wall 10 extending along the length direction of the tank body 1. The tube gallery 2 is arranged outside one end of the cell body 1 in the length direction, i.e. the left end of the cell body 1 as shown in fig. 1, 2 and 4, 5. A plurality of filter material layers 5 are correspondingly paved on the bottom surfaces 11 of the plurality of filter tanks one by one. The back flushing air pipes are arranged in the filter tanks in a one-to-one correspondence manner. The back-flushing air pipe in any filter comprises a back-flushing air distribution square pipe 32 and a back-flushing air inlet main pipe 31. The back flush air distribution pipe 32 is arranged at the bottom end of the partition wall 10 in the filter. Preferably, the length direction of the backwashing air distribution pipe 32 extends along the length direction of the partition wall 10 or the filter or the tank body 1, so that the backwashing branch pipe 33 can cover any position of the filter material layer 5, backwashing is more sufficient and thorough, and the effect is better. And the backwashing gas distribution square pipe 32 is provided with a backwashing branch pipe 33 which can distribute gas towards the filter material layer 5 on the bottom surface 11 of the corresponding filter tank. The back flush air inlet main pipe 31 is arranged below the bottom surface 11 of the filter tank, one end of the back flush air inlet main pipe is connected with the back flush air distribution square pipe 32, and the other end of the back flush air inlet main pipe extends into the pipe gallery space 2 and is connected with a back flush fan (not shown) arranged in the pipe gallery space 2 or an electric room adjacent to the pipe gallery space 2. The part of the back flush air inlet main pipe 31, which is positioned in the pipe gallery space 2, is also provided with a pneumatic butterfly valve 311. The backwash air intake manifold 31 is disposed below the tank bottom surface 11, and the backwash air distribution pipe 32 is not particularly limited as long as the backwash air distribution pipe 33 can distribute air toward the filter material layer 5 on the tank bottom surface 11, and may be entirely below the tank bottom surface 11 or partially below the tank bottom surface 11, that is, partially exposed from the tank bottom surface 11. As shown in fig. 6, the preferred backwash gas distribution pipe 32 in the embodiment of the present invention is partially exposed from the tank bottom surface 11. In the preferred embodiment of the present invention, the backwash air distribution pipe 33 is disposed on the top end surface of the backwash air distribution pipe 32 and the air distribution direction is along the vertical upward direction. In addition, when the separation walls 10 are not arranged in all the filter tanks, the two sides of the bottom ends of all the separation walls 10 are provided with back washing air distribution square pipes 32 for back washing of the filter material layers 5 of the corresponding filter tanks. When the filter chamber is also provided with the partition walls 10, at this time, the back-flushing air distribution square pipes 32 are not required to be arranged at the bottom ends of the two wall surfaces of all the partition walls 10, only the back-flushing air distribution square pipes 32 are required to be arranged at the bottom end of one partition wall 10 or part of partition walls 10 in the filter chamber, and only the back-flushing air pipes in each filter chamber are required to be ensured to carry out air distribution back flushing. In the case of the partition wall 10 in each filter chamber, the filter chamber is not completely partitioned by the partition wall 10 in the filter chamber, for example, only one end is connected to both side walls in the width direction of the filter chamber or both ends are not connected to both side walls in the width direction of the filter chamber. As shown in fig. 3 and 6, only one filter chamber and two partition walls 10 in the filter chamber are shown, wherein a back flush air distribution pipe 32 is respectively arranged on two sides of the bottom end of the left partition wall 10 in the figure, and the back flush air distribution pipe 32 is not arranged on two sides of the bottom end of the right partition wall 10 in the figure. In addition, the partition wall 10 may be provided not only in the longitudinal direction of the filter chamber as shown in FIGS. 3 and 6, but also in both the longitudinal and wide width directions, and the backwash inlet manifold 31 may be provided in the longitudinal direction of the filter chamber regardless of whether the partition wall 10 is provided only in the longitudinal direction of the filter chamber or the partition wall 10 is provided in both the longitudinal and wide width directions. Still be equipped with the water catch bowl 43 that extends towards 2 directions between the pipe gallery on the bottom surface 11 of the pool in filtering pond, the water catch bowl has been linked towards the one end of 2 between the pipe gallery has outlet pipe 44, and the outlet pipe extends to 2 between the pipe gallery in. As shown in fig. 3 or 6, a U-shaped water collecting channel 41 extending in the longitudinal direction of the partition wall 10, that is, in the longitudinal direction of the cell body 1 is provided at the top end of the cell wall in the longitudinal direction of the partition wall 10 and the filter cell. Alternatively, the header channel 41 may be provided only at the top end of the re-partition wall 10 or the header channel 41 may be provided only at the top end of the re-partition wall 10. The water collecting channel 41 is provided with a plurality of overflow holes 45 arranged at intervals along the length direction of the water collecting channel 41 on the wall surface facing the inside of the corresponding filter tank, one end of the water collecting channel 41 facing the pipe gallery 2 is connected with a water collecting pipe 42, the water collecting pipe 42 extends into the pipe gallery 2, a water outlet pipe 44 is connected with a backwashing pump 46, a backwashing valve is arranged on the backwashing pump 46, the backwashing pump 46 is a conventional backwashing pump in the existing market, and the specific structure and the working principle are not described and limited herein, and the person skilled in the art knows. Through the switching of the valve, the water enters the water collecting tank 43 from the water outlet pipe 44 and backwashes the filter material layer 5 upwards. Optionally, the backwash pump 46 may be connected to the water collection pipe 42 to realize circulation, that is, the dirty water after backwashing enters the backwash pump 46 through the water collection pipe 42 and is filtered by the filter in the backwash pump 46 (that is, the backwash pump 46 is a filter backwash pump), and then is backwashed again through the water outlet pipe 44 for use, so as to reduce the use and waste of water resources. The water collecting tank 43, the water outlet pipe 44, the overflow hole 45, the water collecting channel 41, the water collecting pipe 42 and the backwashing pump 46 together constitute a backwashing water pipe assembly. During backwashing, backwashing water enters the water collecting tank 43 through the water outlet pipe 44 by the backwashing pump 46 and flows upwards to perform water distribution backwashing on the filter material layer 5. The dirty water after the reverse washing enters the collecting channel 41 through the overflow hole 45 and is finally discharged through the collecting pipe 42.

It should be noted that, in the embodiment of the present invention, the pool bottom 11 refers to the upper surface of the pool bottom leveled by the mortar, the height of the pool bottom is also the upper surface of the pool bottom not leveled by the mortar, and the height of the pool bottom is slightly lower than the pool bottom 11. The utility model discloses a arrange back flush inlet manifold 31 below tank bottom surface 11, solved among the prior art directly with back flush inlet manifold 31 along vertical direction insert the filter bed 5 and be connected the problem that leads to streaming about taking place easily and influence the problem of backwash effect with the back flush gas distribution pipe at the bottom of the pool, set up 2 between the piping lane, the back flush fan with back flush intake-tube connection and the components and parts on the pipeline and the components and parts setting on the pipeline that are used for the back flush water distribution are 2 between the piping lane of keeping apart with cell body 1, make 1 top surface outward appearance of cell body clean, the visual problem of influence outward appearance that leads to among the prior art has been solved.

According to some preferred embodiments of the present invention, as shown in fig. 2 and 4, the backwash air intake manifold 31 is connected to the corresponding backwash air distribution pipe 32 through a 90 ° elbow pipe 34 (preferably fixed by welding and ensuring that the weld is intact and has no leakage). Optionally, the backwash air intake manifold 31, the backwash air distribution square pipe 32 and the elbow pipe 34 may be connected by other means known to those skilled in the art and easily implemented, such as a threaded connection, which only needs to ensure that the connection is sealed and has no leakage. As shown in fig. 2 and 4, for the case where there is no partition wall 10 in each filter, the backwash air intake manifold 31 of the adjacent two filters is U-shaped. When the partition wall 10 is still present in the filter, the backwash air distribution pipe 32 and the backwash air intake main pipe 31 on both sides of the partition wall 10, which are provided with the backwash air distribution pipe 32 and the backwash air intake main pipe 31, respectively, should be formed in a U shape.

According to some preferred embodiments of the present invention, as shown in fig. 4 to 6, when installing the backwash air intake manifold 31, a part (preferably, the central position of the length of the bottom surface 11, not the central position of the bottom surface of the filter tank, shown as the central position of a long side close to the partition wall 10, is provided with a water collecting tank 43 on the long side far from the partition wall 10) away from the inter-pipe gallery 2 of the bottom surface 11 of the corresponding filter tank is preceded, and the central point of the length of the bottom surface 11 of the filter tank is easy to find and easy to back flush the air distribution pipe 32 and arrange to both sides along the center of the back flush air distribution pipe 32, so as to cover any position of the filter material layer 5, so that the backwashing is more efficient and thorough) below the elevation and open the pipe slot towards the inter-pipe gallery 2 direction. The backwash air intake manifold 31 is laid in the pipe chase (note that the height of the backwash air intake manifold 31 is lower than the depth of the pipe chase) and filled with concrete to the level of the tank bottom surface 11, preferably, leveled with mortar. As shown in fig. 5 and 6, concrete is not poured into the pipe groove at the joint of the backwash air intake main pipe 31 and the backwash air distribution square pipe 32 to reserve an operation space 35 for elbow welding, the operation space 35 is filled with concrete after the welding is completed, and then mortar is used for leveling until the operation space is leveled with the pool bottom surface 11. Correspondingly, the joint of the backwash air inlet main pipe 31 and the corresponding backwash air distribution square pipe 32 is positioned at the center of the length direction of the corresponding filter tank. Preferably, the length center of the back flush air distribution square pipe 32 coincides with the length center of the corresponding filter tank.

According to some preferred embodiments of the present invention, the side of any one of the back-washing air distribution pipes 32 is flush with and fixed to the bottom wall surface of the partition wall 10 of the corresponding filter chamber, and the bottom surface of the back-washing air distribution pipe 32 is flush with and fixed to the lower surface of the bottom surface 11 of the corresponding filter chamber, that is, the back-washing air distribution pipe 32 is partially below the bottom surface 11 and partially above the bottom surface 11. The length direction of the backwashing air distribution square pipe 32 is ensured to be horizontal, the vertical surface is ensured to be vertical, and the backwashing air distribution square pipe is firmly fixed with the wall surface of the pool wall and the pool bottom surface 11. As shown in fig. 6, because the back-washing air distribution square pipe 32 is partially disposed below the pool bottom surface 11 and partially exposed above the pool bottom surface 11 in the embodiment of the present invention, the back-washing air distribution square pipe 32 can be prevented from falling off from the wall surface of the pool wall due to the gravity effect when the filter material layer 5, the air water distribution block layer 7 and the support layer 6 are laid on the pool bottom surface 11 or used for a long time.

According to some preferred embodiments of the present invention, as shown in fig. 1 and fig. 7, a gas-water distribution block 7 composed of a plurality of blocks 71 is further laid on the bottom of the filter material layer 5, and an avoidance gap 72 for passing backwash gas and backwash water and performing backwash toward the filter material layer 5 is formed between adjacent blocks 71. It should be noted that the backwash gas pipe 33 may only face the avoidance gap 72 without extending into the avoidance gap 72, so that the backwash gas can be blown to the filter material layer 5 through the avoidance gap 72. Alternatively, the backwash gas pipe 33 may extend into the escape slit 72 and extend to the filter bed 5. The utility model discloses the filter sand that filter material layer 5 adopted, the specification of filter sand is 2-4 mm's quartz stone filter sand. It should be noted that the size of the avoiding gap 72 is smaller than the specification of the filtered sand, that is, smaller than 2-4mm, so as to prevent the filtered sand from entering the avoiding gap 72 to cause the blockage of the avoiding gap 72, thereby affecting the backwashing effect.

Further preferably, as shown in fig. 1 and 3, a support layer 6 is further provided between the filter material layer 5 and the gas-water distribution block layer 7, and the support layer 6 is pebbles, and in this case, the size of the avoiding gap 72 is not limited to a range of less than 2 to 4 mm. Because the filter material layer 5 is the filter sand with smaller particle size, the pebble layer with larger particle size is arranged at the bottom of the filter material layer 5, so that the filter sand with small particle size can be prevented from blocking the avoiding gap 72 and even blocking the backwashing bronchus 33, and the backwashing effect is influenced. Alternatively, as shown in fig. 7, the block structure 71 is substantially inverted U-shaped.

It should be understood that the above-described embodiments of the present invention are merely illustrative of or explaining the principles of the invention and are not to be construed as limiting the invention. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. Further, it is intended that the appended claims cover all such variations and modifications as fall within the scope and boundaries of the appended claims or the equivalents of such scope and boundaries.

Claims

1. The utility model provides a deep bed filtering pond of denitrification of installation is buried at bottom to back flush intake pipe, includes the cell body, the cell body is including a plurality of filtering pond that is separated by a plurality of partition walls that extend the setting along cell body length direction, its characterized in that still includes:

the filter comprises a filter chamber, a partition wall and/or a filter wall, wherein the filter chamber is provided with a water collecting tank, the bottom surface of the filter chamber is also provided with a water collecting tank extending along the length direction of the filter chamber, one end of the water collecting tank facing the space between the pipe galleries is connected with a water outlet pipe, the top end of the partition wall and/or the top end of the wall of the filter chamber in the length direction is provided with a water collecting channel, the water collecting channel is communicated with the filter chamber through an overflow hole, one end of the water collecting channel facing the space between the pipe galleries is connected with a water collecting pipe, the water collecting pipe and the water outlet pipe both extend into the space between the pipe galleries, and the water outlet pipe is connected with a backwashing pump which flows water into the water collecting tank through the water outlet pipe and flows upwards to carry out water distribution backwashing on the filter material layer.

2. The deep bed denitrification filter with the embedded-bottom installed back-flushing air inlet pipe according to claim 1, wherein the back-flushing air inlet main pipe is connected with the corresponding back-flushing air distribution square pipe through an elbow;

the back-flushing air inlet main pipes of two adjacent filter tanks are U-shaped.

3. The deep bed denitrification filter with the embedded-bottom installed back-flushing air inlet pipe according to claim 2, wherein the back-flushing air inlet main pipe and the corresponding back-flushing air distribution square pipe are welded through an elbow and have no leakage in a welding seam.

4. The deep bed denitrification filter mounted with the backwash air inlet pipe buried at the bottom according to claim 3, wherein when the backwash air inlet main pipe is mounted, a pipe groove is formed downwards and towards the direction between the pipe galleries at a certain position, far away from the pipe galleries, of the bottom surface of the corresponding filter;

laying the backwash air inlet main pipe in the pipe groove and filling concrete to the bottom surface of the pool, wherein the pipe groove at the joint of the backwash air inlet main pipe and the backwash air distribution square pipe is not filled with concrete to reserve an operation space for welding the elbow, and after welding is finished, filling the operation space with concrete until the operation space is level to the bottom surface of the pool.

5. The deep bed filter of claim 4, wherein any one of the tube slots extends from the center of the length of the bottom of the filter chamber to the center of the tube channel.

6. The deep bed filter of claim 1, wherein the side of each backwash air distribution pipe is flush with and fixed to the bottom wall surface of the partition wall of the corresponding filter, and the bottom of each backwash air distribution pipe is flush with and fixed to the bottom surface of the corresponding filter.

7. The deep bed filter of claim 1, wherein the connection between the main backwash inlet pipe and the corresponding backwash air distribution square pipe is located at the center of the length direction of the filter corresponding to the main backwash inlet pipe.

8. The deep bed denitrification filter mounted with the backwash air inlet pipe buried at the bottom according to claim 1, wherein the length direction of any backwash air distribution square pipe extends along the length direction of the corresponding filter; and/or

9. The deep bed denitrification filter with the backwash inlet pipe installed at the buried bottom of the claim 1 is characterized in that a gas-water distribution block layer formed by splicing a plurality of block structures is laid at the bottom of the filter material layer, and an avoidance gap for backwash gas and backwash water to pass through and backwash towards the filter material layer is formed between the adjacent block structures.

10. The deep bed denitrification filter tank with the embedded bottom for backwashing air inlet pipes of claim 9, wherein a bearing layer is further arranged between the filter material layer and the air-water distribution block layer, the filter material layer is filter sand, and the bearing layer is pebbles.