1. A denitrification filter, comprising: the denitrification filter comprises a denitrification filter body, a water inlet pipe (1), a mixing tank (2), a water distribution channel (4), a water distribution weir (6), a water outlet channel (14), a backwashing blower (16) and a backwashing water pump (17);

wherein, one end of the water inlet pipe (1) is connected with an input water source, and the other end is connected with the mixing tank (2); a carbon source adding system (3) is arranged in the mixing tank (2), the mixing tank (2) is communicated with a water distribution channel (4), a gate (5) is arranged in the water distribution channel (4), the water distribution channel (4) is communicated with a water distribution weir (6), a polyurethane soft packing layer is arranged at the lower part of the inner wall of the water distribution weir (6), and a water distribution pipe (7) communicated with the denitrification filter body is arranged at the bottom;

an air-water distribution chamber (8), an air distribution and distribution filter block set (9), a supporting layer (10), a buffer layer (11) and a graphene sponge filler layer (12) are sequentially arranged in the inner cavity of the denitrification filter body from bottom to top, a water outlet weir (13) is arranged near the upper edge of the inner wall of the denitrification filter body, the water outlet weir (13) is connected with a water outlet channel (14) arranged on the outer wall of the denitrification filter body, and a water outlet pipe (15) is arranged at the bottom of the water outlet channel (14) and is used for discharging a treated water source; the water distribution pipe (7), the back flush blower (16) and the back flush water pump (17) are respectively communicated with the gas-water distribution chamber (8).

2. The denitrification filter tank according to claim 1, wherein the carbon source adding system (3) comprises a carbon source storage tank, a carbon source adding pump, a carbon source adding pipeline and a stirrer; wherein, the carbon source feeding pump is communicated with the carbon source storage tank; two ends of the carbon source feeding pipeline are respectively connected with a water inlet pipe (1) and a carbon source feeding pump; the stirrer is arranged in the inner cavity of the mixing pool (2) and mixes the carbon source with the input water source.

3. The denitrification filter tank according to claim 1 or 2, wherein the carbon source dosing system (3) is further provided with a feed-forward-feedback composite control system.

4. A denitrification filter according to any of claims 1-3, wherein the air distribution filter block set (9) is made of high density polyethylene.

5. The denitrification filter of any one of claims 1-4, wherein the support layer (10) is natural quartz sand; more preferably, the natural quartz stone has a particle size of 8 to 38 mm.

6. The denitrification filter according to any one of claims 1-5, wherein the filler of the graphene sponge filler layer (12) is graphene sponge.

7. A denitrification filter according to any one of claims 1-6, wherein the denitrification filter body is provided with a constant liquid level control system.

8. The denitrification filter according to any one of claims 1-7, comprising a central control system, wherein the central control system is electrically connected with a carbon source adding system (3), a gate (5), a constant liquid level control system, a backwashing blower (16) and a backwashing water pump (17), respectively.

Background

In recent years, with the emphasis of national and local pollution control, the national standard requirements for sewage treatment are more strict, and the discharge standard of sewage treatment plants in various regions is gradually improved from primary B of discharge standard of pollutants for municipal sewage treatment plants (GB18918-2002) to primary A standard, or surface IV water body standard, even special discharge limit standard. The high discharge standard is mainly to control organic matters and nitrogen and phosphorus of a sewage treatment plant more strictly, so that the arrangement of advanced treatment process in modification needs to be focused or improved, and particularly the application of a denitrification filter tank needs to be realized.

The denitrification filter tank is a filter tank with denitrification function and capable of further removing total nitrogen, is the most important component in the deep treatment of a sewage treatment plant, and is commonly used at present as an active sand filter tank, a denitrification biological filter tank, a denitrification deep bed filter tank and the like. However, the active sand filter has high investment and complex operation management, and the denitrification biological filter and the deep bed filter have the problems of filler hardening, low concentration of a filter material layer biological membrane, low denitrification load, easy generation of air resistance and the like, thereby greatly influencing the quality of effluent water.

Disclosure of Invention

The invention aims to provide a denitrification filter.

Therefore, the technical scheme of the invention is as follows:

a denitrification filter comprising: the denitrification filter comprises a denitrification filter body, a water inlet pipe, a mixing tank, a water distribution channel, a water distribution weir, a water outlet channel, a backwashing blower and a backwashing water pump;

wherein, one end of the water inlet pipe is connected with an input water source, and the other end is connected with the mixing tank; a carbon source adding system is arranged in the mixing tank, the mixing tank is communicated with a water distribution channel, a gate is arranged in the water distribution channel, the water distribution channel is communicated with a water distribution weir, a polyurethane soft packing layer is arranged at the lower part of the inner wall of the water distribution weir, and a water distribution pipe communicated with the denitrification filter body is arranged at the bottom of the polyurethane soft packing layer;

an air-water distribution chamber, an air distribution and distribution filter brick set, a supporting layer, a buffer layer and a graphene sponge filler layer are sequentially arranged in the inner cavity of the denitrification filter body from bottom to top, a water outlet weir is arranged near the upper edge of the inner wall of the denitrification filter body and is connected with a water outlet channel arranged on the outer wall of the denitrification filter body, and a water outlet pipe is arranged at the bottom of the water outlet channel and is used for discharging a treated water source; the water distribution pipe, the back washing blower and the back washing water pump are respectively communicated with the gas-water distribution chamber.

Preferably, the carbon source adding system comprises a carbon source storage tank, a carbon source adding pump, a carbon source adding pipeline and a stirrer; wherein, the carbon source feeding pump is communicated with the carbon source storage tank; the two ends of the carbon source feeding pipeline are respectively connected with a water inlet pipe and a carbon source feeding pump; the stirrer is arranged in the inner cavity of the mixing pool and mixes the carbon source with the input water source.

Preferably, the carbon source adding system is also provided with a feed-forward-feedback composite control system, the feed-forward flow of the filter tank is automatically obtained, the nitrate concentration and dissolved oxygen DO concentration of the inlet water and the outlet water of the filter tank are combined, the carbon source adding value is periodically corrected in a small proportion by the calculation of built-in software and the feedback mechanism after the nitrate nitrogen is discharged, an instruction is sent to control the carbon source adding amount of the adding pump, the excessive and insufficient carbon source adding is avoided, the accurate adding of the carbon source is ensured, and the quality of the discharged water is ensured.

Preferably, the water and gas distribution filter brick group is made of high-density polyethylene, has excellent structural strength and toughness, ensures that water and gas are uniformly distributed at each diffusion hole on the length of the filter brick in structural design, and provides super-strong backwashing water and gas distribution performance.

Preferably, the bearing layer is natural quartz sand; more preferably, the natural quartz stone has a particle size of 8-38mm, such as 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, 31mm, 32mm, 33mm, 34mm, 35mm, 36mm, 37mm, 38mm and all values in the range, which are not listed due to space limitation. Within the range, the structure of the bearing layer can be ensured to keep stable and certain strength, if the structure is below the range, the strength is insufficient, and the stability and the cost performance are reduced above the range.

Preferably, the filler of the graphene sponge filler layer is graphene sponge, the graphene sponge is a three-dimensional porous network structure formed by mutually crosslinking graphene sheets, the specific surface area is high, the biological adhesiveness is strong, high-concentration denitrifying biological floras inhabit in and out of filler holes are high in denitrifying load, and hardening is not easy to occur. The adsorption capacity of the filter is far higher than that of the traditional filter material, and the specific surface area is high, the porosity is large, so that nitrogen accumulation can not be caused, the air resistance problem of the traditional denitrification filter is greatly relieved, the head loss of the filter in operation is reduced, and the filtering speed of the filter is ensured.

Preferably, the denitrification filter body is provided with a constant liquid level control system, so that the increase of dissolved oxygen caused by over-high water drop of filter inlet water is effectively avoided, carbon source consumption is caused, the thickness of a filter layer in an effective anoxic state is reduced, and the quality of outlet water is influenced.

Preferably, the denitrification filter tank comprises a central control system, and the central control system is respectively and electrically connected with a carbon source feeding system, a gate, a constant liquid level control system, a backwashing blower and a backwashing water pump.

Compared with the prior art, the denitrification filter provided by the invention realizes uniform water distribution of the denitrification filter body through the design of the water distribution channel, the water distribution weir and the gate, and uniformly distributes input water sources; the feed-forward-feedback composite control system is arranged to realize accurate addition of the carbon source, reduce the operation cost and simplify the management complexity. In addition, the problems of filler hardening, low concentration of a filter material layer biofilm, low denitrification load, easy generation of air resistance and the like existing in the prior art for a long time are solved, and the effluent quality is greatly improved.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Detailed Description

The present invention will be further described with reference to the following examples, which are not intended to limit the invention in any way.

As shown in FIG. 1, the denitrification filter provided by the invention comprises: the denitrification filter comprises a denitrification filter body, a water inlet pipe 1, a mixing tank 2, a water distribution channel 4, a water distribution weir 6, a water outlet channel 14, a backwashing blower 16 and a backwashing water pump 17;

wherein, one end of the water inlet pipe 1 is connected with an input water source, and the other end is connected with the mixing tank 2; a carbon source adding system 3 is arranged in the mixing tank 2, the mixing tank 2 is communicated with a water distribution channel 4, a gate 5 is arranged in the water distribution channel 4, the water distribution channel 4 is communicated with a water distribution weir 6, a polyurethane soft packing layer is arranged at the lower part of the inner wall of the water distribution weir 6, and a water distribution pipe 7 communicated with the denitrification filter body is arranged at the bottom;

an air-water distribution chamber 8, an air distribution and distribution filter brick group 9, a supporting layer 10, a buffer layer 11 and a graphene sponge filler layer 12 are sequentially arranged in the inner cavity of the denitrification filter body from bottom to top, a water outlet weir 13 is arranged near the upper edge of the inner wall of the denitrification filter body, the water outlet weir 13 is connected with a water outlet channel 14 arranged on the outer wall of the denitrification filter body, a water outlet pipe 15 is arranged at the bottom of the water outlet channel 14, and a treated water source is discharged; the water distribution pipe 7, the back flush blower 16 and the back flush water pump 17 are respectively communicated with the gas-water distribution chamber 8.

The carbon source adding system 3 comprises a carbon source storage tank, a carbon source adding pump, a carbon source adding pipeline and a stirrer; wherein, the carbon source feeding pump is communicated with the carbon source storage tank; two ends of the carbon source feeding pipeline are respectively connected with a water inlet pipe 1 and a carbon source feeding pump; the stirrer is arranged in the inner cavity of the mixing pool 2 and mixes the carbon source with the input water source.

The carbon source adding system 3 is also provided with a feedforward-feedback composite control system.

The water and gas distribution filter brick set 9 is made of high-density polyethylene.

The bearing layer 10 is made of natural quartz sand; the particle size of the natural quartz stone is 8-38 mm.

The filler of the graphene sponge filler layer 12 is graphene sponge.

The denitrification filter body is provided with a constant liquid level control system.

The denitrification filter tank comprises a central control system, and the central control system is respectively and electrically connected with a carbon source adding system 3, a gate 5, a constant liquid level control system, a backwashing blower 16 and a backwashing water pump 17.

The working principle of the invention is firstly explained as follows:

a water source enters a mixing tank 2 through a water inlet pipe 1, a carbon source adding system 3 in the mixing tank 2 realizes water quality analysis of the water source through a feedforward-feedback composite control system to realize accurate adding, specifically, the amount to be added is calculated through a controller, then a carbon source adding pump extracts the carbon source from a carbon source storage tank, the carbon source is added into the mixing tank 2 through a carbon source adding pipeline, and the carbon source is stirred through a stirrer. Then, a certain amount of water enters the water distribution channel 4, and the instantaneous water amount entering the water distribution pipe 7 is controlled through the cooperation of the gate 5 and the water distribution weir 6; and then the water enters a tank of the denitrification filter body, sequentially passes through an air-water distribution chamber 8, a water and air distribution filter brick group 9, a supporting layer 10, a buffer layer 11 and a graphene sponge filler layer 12, and passes through a backwashing blower 16 and a backwashing water pump 17 when passing through the air-water distribution chamber 8. Then enters the outlet channel 14 through the outlet weir 13 and flows out of the outlet pipe 15 at the bottom of the outlet channel 14, and the denitrification treatment is completed.

In conclusion, the denitrification filter provided by the invention realizes uniform water distribution of the denitrification filter body through the design of the water distribution channel, the water distribution weir and the gate, and uniformly distributes input water sources; the feed-forward-feedback composite control system is arranged to realize accurate addition of the carbon source, reduce the operation cost and simplify the management complexity. In addition, the problems of filler hardening, low concentration of a filter material layer biofilm, low denitrification load, easy generation of air resistance and the like existing in the prior art for a long time are solved, and the effluent quality is greatly improved.

It is to be noted and understood that various modifications and improvements can be made to the invention described in detail above without departing from the spirit and scope of the invention as claimed in the appended claims. Accordingly, the scope of the claimed subject matter is not limited by any of the specific exemplary teachings provided.

The applicants hereby give notice that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.