CN112142198A - Denitrification reaction sewage treatment system - Google Patents

Abstract

A denitrification sewage treatment system comprising: a water inlet part for inputting sewage to be treated; the peristaltic pump is used for conveying the sewage of the water inlet part to the reactor; a reactor for purifying sewage by a denitrification reaction; the water outlet pipe is arranged at the bottom of the reactor and is used for outputting the water purified by the reactor; the input sewage with different C/N ratios is stored in different containers, and the sewage in the different containers is mixed into the sewage with the expected C/N ratio and input into the reactor for treatment, so that the carbon source is reasonably distributed and efficiently utilized, and the efficient denitrification efficiency is ensured.

Description

Denitrification reaction sewage treatment system

Technical Field

The invention relates to the technical field of sewage treatment, in particular to a denitrification sewage treatment system.

Background

Water is an indispensable resource for human beings to live and develop, the pressure of water resource environment is continuously increased along with the rapid growth of population and the deep promotion of urbanization and industrialization, and the problem of water pollution is increasingly serious, so that the water becomes an important factor for restricting the social and economic development.

The prior process for denitrification and denitrification of sewage mainly comprises a physical and chemical method and a biological method. The physical and chemical methods comprise ion exchange, electrodialysis, reverse osmosis and the like, the capital construction and daily operation costs of the methods are high, and the high-salinity wastewater generated during operation is not easy to treat. The biological method utilizes denitrifying bacteria to convert NO 3-N into nontoxic and harmless nitrogen, has low cost, and is the most widely used denitrification technology which is the best developed at present. In the biological denitrification process, carbon source organic matters play an important role, and are not only carbon source substances for survival and propagation of heterotrophic denitrifying bacteria, but also hydrogen donors for denitrification conversion of nitrates.

In the biological treatment process, an organic carbon source in sewage is generally used as a nutrient element for growth of the sewage, but certain requirements are imposed on C/N, and if the carbon source is insufficient, the growth of microorganisms is influenced, so that the normal denitrification reaction is changed, and the denitrification efficiency is poor. Therefore, how to reasonably distribute and efficiently utilize the limited carbon resources becomes a problem which needs to be solved urgently in sewage treatment.

In the prior art, in order to ensure high-efficiency denitrification efficiency, an additional carbon source is arranged in a sewage treatment device to improve the C/N ratio of sewage, so that the denitrification efficiency is improved. However, since the value of the C/N ratio in the sewage is not fixed and constant, and the C/N of the sewage is different at different stages, when the C/N ratio of the sewage is changed, for the sewage treatment with high C/N, too much extra carbon source is not needed, the carbon source in the sewage treatment device can increase the extra sludge yield, and waste of the carbon source can be generated.

Disclosure of Invention

The present invention addresses the above-described deficiencies of the prior art by providing a sewage treatment system and a sewage treatment method that address the above-described problems.

As an aspect of the present invention, there is provided a sewage treatment system comprising: a water inlet part for storing sewage to be treated; the peristaltic pump is used for conveying the sewage of the water inlet part to the reactor through the water inlet pipe; a reactor for performing sewage purification by denitrification reaction; the water outlet pipe is arranged at the bottom of the reactor and used for outputting the purified water passing through the reactor; the water inlet part comprises a buffer part which is provided with a C/N ratio detector for detecting the C/N ratio of sewage in the buffer part; the water inlet tank is used for introducing the sewage in the buffer part into the water inlet tank when the C/N ratio of the buffer part is between a first threshold value and a second threshold value; a first water storage tank for inputting the sewage of the buffer part into the first water storage tank when the C/N ratio of the buffer part is larger than a first threshold value; a second water storage tank for inputting the sewage of the buffer part into the second water storage tank when the C/N ratio of the buffer part is less than a second threshold value; a C/N determining part which determines the C/N ratio in the first water storage tank or the second water storage tank when the first water storage tank or the second water storage tank is introduced with the sewage of the buffer part; a blending part which inputs the sewage in the first water storage tank and the sewage in the second water storage tank with determined proportion into a water inlet part according to the C/N ratio of the sewage in the first water storage tank, the C/N ratio in the second water storage tank and the expected C/N ratio; and the controller is used for conveying the sewage of the water inlet part to the reactor for treatment through the peristaltic pump when the height of the sewage in the water inlet tank is greater than a threshold value.

Furthermore, the volume of the water inlet tank is 2-3 times that of the first water storage tank and the second water storage tank.

Furthermore, the volume of the buffer part is 1/8-1/4 of the volume of the first water storage tank and the second water storage tank.

Further, the C/N determining part determines the C/N ratio in the first water storage tank or the second water storage tank as follows: tn = (ToVo + Tvff)/(Vo + Vf), wherein To is the C/N ratio in the first water storage tank or the second water storage tank before the sewage is introduced into the buffer part, Vo is the anhydrous volume in the first water storage tank or the second water storage tank before the sewage is introduced into the buffer part, Tf is the C/N ratio of the sewage in the buffer part, and Vf is the sewage volume in the buffer part.

Further, the mixing part determines the ratio X = (T2-Te)/(Te-T1) of the sewage in the first water storage tank and the sewage in the second water storage tank according to the following way; where T2 is the C/N ratio in the second tank, T1 is the C/N ratio in the first tank, and Te is the expected C/N ratio.

Further, a denitrification reaction packing layer is arranged in the reactor; the denitrification reaction filler layer contains a solid carbon source, and the content of the solid carbon source increases along with the increase of the height of the filler layer; a water inlet channel is arranged in the reactor, and the water inlet channel comprises an outer wall with a water outlet hole on the side surface and a height adjusting part; the height adjusting part comprises a fixed bottom and a plurality of height adjusting blocks; and the controller determines the height of the height adjusting part when the sewage in the water inlet tank enters the reactor for purification according to the C/N ratio of the sewage in the water inlet tank.

Furthermore, the water inlet channel penetrates through the denitrification reaction filler layer.

Further, when the sewage in the water inlet tank enters the reactor for purification, the height of the height adjusting part is reduced along with the increase of the C/N ratio of the sewage in the water inlet tank.

Further, the reactor is internally provided with a plurality of water inlet channels.

Furthermore, the height of the water inlet pipe is the same as the highest position of the denitrification reaction packing layer.

Furthermore, the denitrification reaction filler layer is a biological denitrification reaction filler layer.

Further, the biological denitrification reaction filler layer comprises a filler and a solid carbon source.

Further, the filler is ceramsite.

Further, the solid carbon source includes corncob, bagasse, sapropel, and the like.

Furthermore, the volume content of the solid carbon source is 10-20% at the bottom of the denitrification reaction filler layer and 50-60% at the top of the denitrification reaction filler layer.

Furthermore, the height of the single height adjusting block is equal to the distance between the water outlet holes on the outer wall.

Further, the height adjusting part closes the water outlet hole below the height of the height adjusting part.

As another aspect of the present invention, there is provided a sewage treatment method comprising the steps of: (1) introducing the sewage into a buffer part, detecting the C/N ratio of the buffer part after the buffer part is filled, and entering the step (5) if the C/N ratio is between a first threshold value and a second threshold value, or entering the step (2); (2) when the C/N ratio of the buffer part is larger than a first threshold value, inputting the sewage of the buffer part into a first water storage tank; when the C/N ratio of the buffer part is smaller than a first threshold value, inputting the sewage of the buffer part into a second water storage tank; (3) when the first water storage tank or the second water storage tank is filled with the sewage of the buffer part, determining the C/N ratio in the first water storage tank or the second water storage tank; (4) inputting the sewage in the first water storage tank and the sewage in the second water storage tank of the water inlet tank into a water inlet part according to the C/N ratio of the sewage in the first water storage tank, the C/N ratio in the second water storage tank and the expected C/N ratio; (5) and (3) when judging whether the height of the sewage in the water inlet tank is greater than a threshold value, if so, conveying the sewage in the water inlet part to the reactor through the peristaltic pump for treatment, and otherwise, returning to the step (1).

Drawings

FIG. 1 is a schematic view of the composition of a sewage treatment system according to an embodiment of the present invention.

FIG. 2 is a schematic view showing the composition of a reactor of the sewage treatment system according to the preferred embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

Referring to fig. 1, the sewage treatment system according to the embodiment of the present invention includes a water inlet part for inputting sewage to be treated. The water inlet part comprises a buffer part 10, a water inlet tank 11, a first water storage tank 12 and a second water storage tank 13. A sewage line to be treated is inputted to the buffer section 10, and the buffer section 10 is provided with a C/N ratio detector for detecting the C/N ratio of the sewage in the buffer section 10. The water inlet tank 11 is connected with the buffer part 10 and the peristaltic pump 20 through valves and is used for storing sewage needing to enter the reactor 40; when the C/N ratio of the buffer part 10 is between the first threshold value and the second threshold value, the sewage in the buffer part 10 is introduced into the water inlet tank 11. Inputting the sewage of the buffer part 10 into the first water storage tank 12 when the C/N ratio of the buffer part 10 is larger than a first threshold value; and when the C/N ratio of the buffer part 10 is smaller than a second threshold value, inputting the sewage of the buffer part 10 into a second water storage tank. The first threshold value corresponds to sewage with high C/N ratio and can be set to be 10-12, and the second threshold value corresponds to sewage with low C/N ratio and can be set to be 2-4. Can set up buffer 10, the case 11 of intaking, the volume of first storage water tank 12, second storage water tank 13, specifically can set up into case 11 and be 2~3 times of first storage water tank 12, the second storage water tank 13 volume, the volume of buffer 10 is 1/8~1/4 of first storage water tank 12, the second storage water tank 13 volume.

And a C/N determining part which determines the C/N ratio in the first water storage tank 12 or the second water storage tank 13 when the sewage in the buffer part 10 is introduced into the first water storage tank 12 or the second water storage tank 13. Specifically, the C/N determining section determines the C/N ratio in the first water storage tank 12 or the second water storage tank 13 as follows: tn = (ToVo + TfVf)/(Vo + Vf), where To is the C/N ratio of the sewage in the first water storage tank 12 or the second water storage tank 13 before the sewage is introduced into the buffer portion, Vo is the volume of the sewage in the first water storage tank 12 or the second water storage tank 13 before the sewage is introduced into the buffer portion, Tf is the C/N ratio of the sewage in the buffer portion 10, and Vf is the volume of the sewage in the buffer portion 10.

And a blending part for inputting the sewage in the first water storage tank 12 and the sewage in the second water storage tank 13 in a determined ratio into the water inlet tank 11 according to the C/N ratio of the sewage in the first water storage tank 12, the C/N ratio of the sewage in the second water storage tank 13 and the expected C/N ratio after the sewage is introduced into the first water storage tank 12 or the second water storage tank 13. Specifically, the blending part determines the ratio X = (T2-Te)/(Te-T1) of the sewage in the first water storage tank 12 and the sewage in the second water storage tank 13 as follows; where T2 is the C/N ratio in the second tank 13, T1 is the C/N ratio in the first tank 12, and Te is the expected C/N ratio.

And a peristaltic pump 20 for delivering the sewage from the water inlet tank 10 to the reactor 40 through the water inlet pipe 30. When the height of the sewage in the water inlet tank 11 is greater than the threshold value, the controller conveys the sewage in the water inlet part 11 to the reactor 40 through the peristaltic pump 20 for treatment. The reactor 40 is subjected to a denitrification reaction to purify the sewage. And the water outlet pipe 50 is arranged at the bottom of the reactor 40 and is used for outputting the purified water passing through the reactor 40.

In a preferred embodiment of the present invention, referring to FIG. 2, a layer 41 of denitrification reaction packing is provided in the reactor 40. The denitrification reaction filler layer 41 is a biological denitrification reaction filler layer, and comprises a filler and a solid carbon source. The filler can be ceramsite with the particle size of 4-10 mm. The solid carbon source can be agricultural waste such as corn cobs, bagasse, sapropel and the like, and can also be biodegradable polymers. Different contents of solid carbon sources are set for different heights of the denitrification reaction filler layer 41, and the content of the solid carbon sources increases with the increase of the height of the denitrification reaction filler layer 41. For example, the volume content of the solid carbon source can be increased from 10-20% of the bottom of the denitrification reaction filler layer 41 to 50-60% of the top. The reactor 40 is provided with one or more water inlet channels 42, one water inlet channel 42 is located at the center of the reactor 40, and when the number of the water inlet channels 42 is multiple, the water inlet channels are uniformly distributed in the reactor 40. The inlet of the inlet pipe 30 is positioned in the inlet channel 42, and the height of the inlet pipe is the same as the highest position of the denitrification reaction packing layer 41.

The water inlet channel 42 penetrates through the denitrification reaction packing layer 41 and comprises an outer wall 43 with a water outlet hole 46 on the side surface and a height adjusting part. The height adjustment portion includes a fixed base 44 and a plurality of height adjustment blocks 45. The height of the single height adjusting block 45 is equal to the distance between the outer wall water outlet holes 46. The height adjustment block 45 is closed at the top and at the sides, and after it is placed on the fixed bottom 44, closes off the outlet opening 46 of the outer wall 43 below its height. And a control part for determining the height of the height adjusting part when the sewage in the water inlet tank 30 enters the reactor 40 for purification according to the C/N ratio of the sewage in the water inlet tank 30, wherein the height of the height adjusting part is reduced along with the increase of the C/N ratio of the sewage in the water inlet tank. Specifically, an altimeter corresponding to the C/N ratio can be set, the controller searches for the corresponding height in the altimeter according to the C/N ratio of the sewage in the water inlet tank 30, and the height adjusting block 45 is placed into the water inlet channel 42 or taken out from the water inlet channel 42, so that the height of the height adjusting part in the water inlet channel 42 reaches the expected height.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. The particular features, structures, materials, or characteristics described in this disclosure may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.

Claims (4)

1. A wastewater treatment system comprising: a water inlet part for inputting sewage to be treated; the peristaltic pump is used for conveying the sewage of the water inlet part to the reactor; a reactor for purifying sewage by a denitrification reaction; the water outlet pipe is arranged at the bottom of the reactor and is used for outputting the water purified by the reactor; the method is characterized in that: the water inlet part comprises a buffer part which is provided with a C/N ratio detector for detecting the C/N ratio of sewage in the buffer part; the water inlet tank is used for introducing the sewage in the buffer part into the water inlet tank when the C/N ratio of the buffer part is between a first threshold value and a second threshold value; a first water storage tank for inputting the sewage of the buffer part into the first water storage tank when the C/N ratio of the buffer part is larger than a first threshold value; a second water storage tank for inputting the sewage of the buffer part into the second water storage tank when the C/N ratio of the buffer part is less than a second threshold value; a C/N determining part which determines the C/N ratio in the first water storage tank or the second water storage tank when the first water storage tank or the second water storage tank is introduced with the sewage of the buffer part; a mixing part which inputs the sewage in the first water storage tank and the sewage in the second water storage tank with determined proportion into the water inlet tank according to the C/N ratio of the sewage in the first water storage tank, the C/N ratio in the second water storage tank and the expected C/N ratio; and the controller is used for conveying the sewage of the water inlet part to the reactor for treatment through the peristaltic pump when the height of the sewage in the water inlet tank is greater than a threshold value.

2. The wastewater treatment system according to claim 1, wherein: the volume of the water inlet tank is 2-3 times of the volume of the first water storage tank and the volume of the second water storage tank.

3. The wastewater treatment system according to claim 1, wherein: the volume of the buffer part is 1/8-1/4 of the volumes of the first water storage tank and the second water storage tank.

4. The wastewater treatment system according to claim 1, wherein: the C/N determining part determines the C/N ratio in the first water storage tank or the second water storage tank according to the following modes: tn = (ToVo + Tvff)/(Vo + Vf), wherein the ratio of C/N in the first water storage tank or the second water storage tank when sewage is not introduced into the buffer portion, the volume of no water in the first water storage tank or the second water storage tank when the sewage is not introduced into the buffer portion, Tf is the ratio of C/N of the sewage in the buffer portion, and Vf is the volume of the sewage in the buffer portion.

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