A device for realizing simultaneous nitrification, denitrification and denitrification of sewage and a method for using the device

Abstract

The present invention discloses a device for realizing simultaneous nitrification and denitrification of sewage denitrification, wherein the reaction chamber used comprises: an inlet pipe, an inlet guide plate, a reactor middle partition, a flow guide plate, a sludge sedimentation inclined plate, a perforated aeration pipe and an overflow weir plate. The reaction chamber is divided into an inlet area, a nitrification reaction area and a sludge sedimentation area; the reactor middle partition is installed at an angle to divide the entire reactor into two parts, the upper end of the partition is connected to the flow guide plate, the bottom end of the partition is connected, and a perforated aeration pipe is laid at the bottom end of the partition, and the lift effect of bubbles is used to cause the two sides of the partition to form ascending and descending flow fields of sludge mixed liquid in sequence. Nitrogen-containing wastewater undergoes nitrification reaction after aeration and mixing, and enters the sedimentation area through the flow guide plate for denitrification reaction. The mud-water mixture deposited at the bottom of the sedimentation area is pulled by bubbles and passes through the channel at the bottom end of the middle partition to enter the ascending flow field again. This system realizes unpowered reflux and performs circulation treatment by reasonably arranging the guide plate and aeration device.

Description

Technical Field

[0001] The invention relates to the technical field of biological denitrification, and in particular to a device for realizing simultaneous nitrification and denitrification of sewage and a use method thereof. Background Art

[0002] Nitrogen is an essential nutrient for the growth and reproduction of microorganisms, but excessive nitrogen content in natural water bodies can easily lead to eutrophication of water bodies, resulting in the crazy growth of lower organisms (such as cyanobacteria) in the water body, and eventually causing the water body to turn black and smelly. The main methods for removing nitrogen from water bodies include physical and chemical methods, microbial activated sludge method and other methods.

[0003] The physical and chemical method is used to treat ammonia nitrogen wastewater. It is a treatment process that mainly uses physical and chemical means to force the ammonia nitrogen in the wastewater to transform or be oxidized and reduced. The main methods used in industry are air stripping, chemical precipitation, breakpoint chlorination and ion exchange.

[0004] Microbial activated sludge denitrification generally refers to the oxidation of NH4+-N in sewage into N2 through a series of processes such as microbial metabolism, ammoniation reaction, nitrification, and denitrification under the action of specific microorganisms in activated sludge, thereby achieving sewage denitrification. Biological denitrification has great advantages such as stable treatment effect and wide application range, and is widely used in industry.

[0005] The traditional biological denitrification process is to separate the nitrification reaction and the denitrification reaction in two different reactors. In the nitrification stage, NH4+-N in the sewage is first oxidized to NO2--N by ammonia oxidizing bacteria (AOB), then oxidized to NO3--N by nitrite oxidizing bacteria (NOB), and then reduced to N2 by denitrifying bacteria. This results in a long process flow, a large floor space, and a high project investment cost.

[0006] Simultaneous nitrification and denitrification (SND) utilizes the interaction of multiple denitrifying bacteria in a structure to achieve nitrification and denitrification reactions in the same reactor at the same time. It has the advantages of small footprint, low oxygen consumption, and no need to adjust pH. However, there are many environmental factors that affect the denitrification effect of simultaneous nitrification and denitrification, such as dissolved oxygen (DO), nutrient ratio (C / N), pH, sludge concentration (MLSS) and sludge age (SRT), and the operation is relatively complicated, making it difficult to control its optimal operating conditions in actual projects. Summary of the invention

[0007] In order to solve the problems existing in the background technology, the purpose of the present invention is to provide a sewage denitrification treatment device which can realize simultaneous nitrification and denitrification, has a short process flow, unpowered sludge return, good effluent water quality and simple control.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A device for realizing simultaneous nitrification, denitrification and denitrification of sewage comprises an aerator, a gas flowmeter and a reaction chamber; the reaction chamber mainly comprises a reaction tank body, a water inlet pipe, a water inlet guide plate, a flow guide plate, a reactor middle partition plate, a sludge sedimentation zone inclined plate, an automatic heater, a perforated aeration pipe and an overflow weir; the water inlet guide plate, the flow guide plate, the reactor middle partition plate and the sludge sedimentation zone inclined plate are fixedly arranged on the side wall of the reaction tank body in sequence, and the reaction tank body is divided into a water inlet zone, a reaction zone and a sedimentation zone; the aerator and the gas flowmeter are connected to the perforated aeration pipe in the reaction chamber through a gas pipeline.

[0010] Furthermore, it also includes a temperature controller, which is arranged at the upper part of the reaction zone; the automatic heater is arranged at the lower part of the reaction zone; the water inlet guide plate is arranged close to the water inlet, and forms a water inlet zone with the side wall of the reaction tank body; the water inlet guide plate is installed in an inclined manner, and its angle with the bottom of the reaction tank body is 45° to 60°, and its top is level with the total height of the reaction tank body.

[0011] Furthermore, the flow guide plate is installed at an angle of 10° to 15° with the bottom of the reaction tank, with its top being 1-10 cm lower than the top of the overflow weir and its bottom being 5-10 cm higher than the bottom of the water inlet guide plate.

[0012] Furthermore, the partition in the reactor is installed in an inclined manner, with an angle of 75° to 85° with the bottom of the reaction tank body, and its top end is located at 2 / 3 of the flow guide plate.

[0013] Furthermore, the perforated aeration pipe is installed horizontally, and the installation position is located directly below the bottom end of the middle partition of the reactor; the aeration pipe has holes staggered 45 degrees downward, and the opening position is toward the water inlet side, and the opening diameter is 1-5mm.

[0014] Furthermore, the inclined plate in the sludge sedimentation area is installed in an inclined manner, and the installation position is located on the left side of the aeration pipe, and the angle between it and the bottom of the reaction tank body is 45° to 65°.

[0015] A method for simultaneous nitrification and denitrification of sewage, the main steps of which are as follows: a) introducing sewage into a reaction chamber containing activated sludge, changing the flow direction of sewage through the diversion of the water inlet guide plate, prompting the nitrogen-containing sewage to flow to the bottom of the reaction tank and mix with the activated sludge in the reaction zone; b) providing dissolved oxygen through the aeration system, and nitrifying bacteria to cause nitrification reaction; c) the buoyancy brought by the rising bubbles in the aeration pipe drives the sludge mixture to pass through the flow guide plate and slowly enter the sedimentation zone; d) in the sedimentation zone, due to the reduction of dissolved oxygen, Denitrification reaction occurs in the system; part of the sewage overflows out of the reactor through the overflow weir, and the other part of the mud-water mixture flows back to the reaction zone through the channel at the bottom end of the partition in the middle of the reactor due to the traction force generated by the rising aeration bubbles in the perforated aeration pipe, and mixes with the mixed liquid in the reaction zone. Under the combined effect of the impact force of the inlet water flow and the buoyancy caused by the rising bubbles, the reflux liquid, the nitrified sludge mixed liquid and the nitrogen-containing sewage form a circulation in the reaction zone, thereby realizing circulation, unpowered reflux, unpowered mixing and stirring, and simultaneous nitrification, denitrification and denitrification.

[0016] Furthermore, when the aeration system provides aeration, the dissolved oxygen (DO) concentration in the reaction zone is controlled to be 1.0 to 2.5 mg / L.

[0017] Furthermore, the sludge concentration (MLSS) in the reaction zone is controlled to be 3500 mg / L to 5500 mg / L, and the sludge age (SRT) is 30-35 days.

[0018] Furthermore, the pH value of the influent is controlled to be 7.5-8.0; the carbon-nitrogen ratio (C / N) of the influent is controlled to be 1:1-3:1; if the carbon source of the influent is insufficient, additional carbon source needs to be added, and the carbon source includes but is not limited to glucose, methanol, ethanol, flour, etc.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] Through the unique internal design of the sewage simultaneous nitrification, denitrification and denitrification device, the water inlet guide plate changes the flow direction of the water, causing the water to flow quickly toward the bottom of the reaction tank. After mixing with the sludge in the reaction zone to undergo nitrification, the water slowly enters the sedimentation zone through the flow guide plate. After sedimentation, a part of the upper clear water overflows the system through the overflow weir, and a part of the mud-water mixture flows back to the reaction zone through the channel at the bottom end of the partition in the middle of the reactor due to the traction force generated by the rising aeration bubbles in the perforated aeration pipe, and mixes with the mixed liquid in the reaction zone, and forms a circulation in the reaction zone, thereby achieving the purpose of unpowered reflux, unpowered mixing and stirring, and simultaneous nitrification, denitrification and denitrification.

[0021] The perforated aeration pipe is installed horizontally, and its installation position is just below the bottom of the middle partition of the reactor. It can not only play the role of aeration, but also increase the fluidity of sewage in the reaction tank, that is, increase the aeration effect.

[0022] The unique design of this application further highlights the advantages of the simultaneous nitrification and denitrification denitrification device, such as small footprint, low oxygen consumption, and no need to adjust pH value.

[0023] The application is simple to operate and its optimal operating conditions can be easily controlled in actual engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A cross-sectional view of the internal structure of a device for achieving simultaneous nitrification and denitrification of sewage

[0025] Markings in the figure: 1. Reaction tank body; 2. Water inlet; 3. Water inlet guide plate; 4. Temperature controller; 5. Flow guide plate; 6. Reactor middle partition; 7. Overflow weir; 8. Sludge sedimentation area inclined plate; 9. Aerator; 10. Gas flow meter; 11. Perforated aeration pipe; 12. Automatic heater. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] See also Figure 1 In an embodiment of the present invention, a device for realizing simultaneous nitrification, denitrification and denitrification of sewage comprises an aerator 9, a gas flowmeter 10 and a reaction chamber; the reaction chamber mainly comprises a reaction tank body 1, a water inlet pipe 2, a water inlet guide plate 3, a temperature controller 4, a flow guide plate 5, a reactor middle partition plate 6, a sludge sedimentation zone inclined plate 8, an automatic heater 12, a perforated aeration pipe 11 and an overflow weir 7; the water inlet guide plate 3, the flow guide plate 5, the reactor middle partition plate 6 and the sludge sedimentation zone inclined plate 8 are fixedly arranged on the side wall of the reaction tank body 1 in sequence, dividing the reaction tank body 1 into a water inlet zone, a reaction zone and a sedimentation zone; the aerator 9 and the gas flowmeter 10 are connected to the perforated aeration pipe 11 in the reaction chamber through a gas pipeline; the temperature controller 4 is arranged at the upper part of the reaction zone; and the automatic heater 12 is arranged at the lower part of the reaction zone.

[0028] The water inlet guide plate 3 is installed in an inclined manner, and the angle between it and the bottom of the reaction tank body 1 is 45° to 60°. The top of the water inlet guide plate 3 is installed in an inclined manner, and the angle between it and the bottom of the reaction tank body 1 is 10° to 15°. The top of the water inlet guide plate 5 is installed in an inclined manner, and the angle between it and the bottom of the reaction tank body 1 is 10° to 15°. The top of the water inlet guide plate 5 is 1-10 cm lower than the top of the overflow weir 7, and the bottom of the water inlet guide plate 3 is 5-10 cm higher than the bottom of the water inlet guide plate 3. The middle partition plate 6 of the reactor is installed in an inclined manner, and the angle between it and the bottom of the reaction tank body 1 is 45° to 60°. The bottom angle is 75° to 85°, and the top is located at 2 / 3 of the flow guide plate 3; the perforated aeration pipe 11 is installed horizontally, and the installation position is located directly below the bottom end of the middle partition plate 6 of the reactor; the perforated aeration pipe 11 is staggered 45 degrees downward, and the opening position is toward the water inlet side, and the opening diameter is 1-5mm; the sludge sedimentation area inclined plate 8 is installed in an inclined manner, and the installation position is located on the left side of the perforated aeration pipe 11, and the angle between it and the bottom of the reaction tank body 1 is 45° to 65°; when in use, the sewage is introduced into the reaction tank body 1 filled with activated sludge, and the sewage flow direction is changed through the diversion of the water inlet guide plate 3, so that the nitrogen-containing sewage flows to the bottom of the reaction tank body 1 and mixed with the activated sludge in the reaction zone; dissolved oxygen is provided by the aeration system, and nitrifying bacteria undergo nitrification reaction; the buoyancy brought by the rising bubbles in the perforated aeration pipe 11 drives the sludge mixed liquid through the flow guide plate 5 and slowly enters the sedimentation zone; in the sedimentation zone, due to the reduction of dissolved oxygen, the system undergoes denitrification reaction; part of the sewage overflows out of the reaction chamber through the overflow weir 7, and the other part of the mud-water mixture flows back to the reaction zone through the bottom channel of the middle partition plate 6 of the reactor, and is mixed with the mixed liquid in the reaction zone by the traction force generated by the rising aeration bubbles in the perforated aeration pipe 11. Under the combined action of the impact force of the inlet water flow and the buoyancy caused by the rising bubbles, the reflux liquid and the nitrifying sewage are The sludge mixture and nitrogen-containing sewage form a circulation in the reaction zone, thereby realizing circulation, unpowered reflux, unpowered mixing and stirring, and simultaneous nitrification, denitrification and denitrification; when the aeration system provides aeration, the dissolved oxygen (DO) concentration in the reaction zone is controlled to be 1.0-2.5 mg / L; the sludge concentration (MLSS) in the reaction zone is controlled to be 3500 mg / L-5500 mg / L, and the sludge age (SRT) is 30-35 d; the influent pH value is controlled to be 7.5-8.0; the influent carbon-nitrogen ratio (C / N) is controlled to be 1:1-3:1; if the influent carbon source is insufficient, additional carbon source needs to be added, and the carbon source includes but is not limited to glucose, methanol, ethanol, flour, etc.

[0029] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for realizing simultaneous nitrification and denitrification of sewage, characterized in that The invention comprises an aerator, a gas flowmeter and a reaction chamber; the reaction chamber mainly comprises a reaction tank body, a water inlet pipe, a water inlet guide plate, a flow guide plate, a reactor middle partition plate, a sludge sedimentation zone inclined plate, an automatic heater, a perforated aeration pipe and an overflow weir; the water inlet guide plate, the flow guide plate, the reactor middle partition plate and the sludge sedimentation zone inclined plate are fixedly arranged on the side wall of the reaction tank body in sequence, and the reaction tank body is divided into a water inlet zone, a reaction zone and a sedimentation zone; the aerator and the gas flowmeter are connected to the perforated aeration pipe in the reaction chamber through a gas pipeline; the flow guide plate is installed in an inclined manner, and the angle between it and the bottom of the reaction tank body is 10°~15°, and its top is lower than The top of the overflow weir is 1-10cm, and its bottom is 5-10cm higher than the bottom of the water inlet guide plate; the middle partition of the reactor is installed in an inclined manner, and its angle with the bottom of the reaction tank body is 75°~85°, and its top is located at 2 / 3 of the flow guide plate; the perforated aeration pipe is installed horizontally, and the installation position is directly below the bottom of the middle partition of the reactor; the aeration pipe has holes staggered 45 degrees downward, and its opening position is toward the water inlet side, and the opening diameter is 1-5mm; the inclined plate of the sludge sedimentation area is installed in an inclined manner, and the installation position is located on the left side of the aeration pipe, and its angle with the bottom of the reaction tank body is 45°~65°.

2. The device for realizing simultaneous nitrification and denitrification of sewage according to claim 1, characterized in that: It also includes a temperature controller, which is arranged at the upper part of the reaction zone; the automatic heater is arranged at the lower part of the reaction zone; the water inlet guide plate is arranged close to the water inlet, and forms a water inlet zone with the side wall of the reaction tank body; the water inlet guide plate is installed in an inclined manner, and its angle with the bottom of the reaction tank body is 45°~60°, and its top is level with the total height of the reaction tank body.

3. A method for treating wastewater by simultaneous nitrification and denitrification using the device for achieving simultaneous nitrification and denitrification of wastewater according to any one of claims 1 to 2, characterized in that: The treatment method comprises the following steps: a) introducing sewage into a reaction chamber containing activated sludge, changing the flow direction of sewage through the water inlet guide plate, causing nitrogen-containing sewage to flow to the bottom of the reaction tank and mix with the activated sludge in the reaction zone; b) providing dissolved oxygen through the aeration system, and causing nitrifying bacteria to undergo nitrification reaction; c) the buoyancy brought by the rising bubbles in the aeration pipe drives the sludge mixed liquid to pass through the flow guide plate and slowly enter the sedimentation zone; d) in the sedimentation zone, due to the reduction of dissolved oxygen, the system undergoes a denitrification reaction; a part of the sewage overflows out of the reactor through the overflow weir, and another part of the mud-water mixture flows back to the reaction zone through the channel at the bottom end of the middle partition of the reactor by the traction force generated by the rising aeration bubbles in the perforated aeration pipe, and mixes with the mixed liquid in the reaction zone; under the combined action of the impact force of the inlet water flow and the buoyancy caused by the rising bubbles, the reflux liquid, the nitrified sludge mixed liquid and the nitrogen-containing sewage form a circulation in the reaction zone, thereby realizing circulation, unpowered reflux, unpowered mixing and stirring, and synchronous nitrification, denitrification and denitrification.

4. The method for treating wastewater by simultaneous nitrification and denitrification according to claim 3, characterized in that: When the aeration system provides aeration, the dissolved oxygen concentration in the reaction zone is controlled to be 1.0~2.5mg / L.

5. The method for treating wastewater by simultaneous nitrification and denitrification according to claim 3, characterized in that: The sludge concentration in the reaction zone is controlled to be 3500mg / L~5500mg / L, and the sludge age is 30-35d.

6. The method for treating wastewater by simultaneous nitrification and denitrification according to claim 3, characterized in that: The pH value of the influent is controlled at 7.5-8.0; the carbon-nitrogen ratio of the influent is controlled at 1:1-3:1; if the carbon source of the influent is insufficient, additional carbon source needs to be added, and the carbon source includes but is not limited to glucose, methanol, ethanol, and flour.

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