A sulfur autotrophic denitrification expanded bed reactor

Abstract

The utility model relates to a kind of sulphur autotrophy denitrification expanded bed reactor, including reactor main body, the bottom of inverted cone of reactor main body lower part is equipped with slag discharge port, water inlet distribution pipe connected with water inlet pipe is set in inverted cone upper portion, the cylindrical inner bottom of reactor main body middle part is equipped with support plate, support plate upper surface is paved with support layer, support layer upper portion is equipped with packing loading area, packing loading area upper portion is packing expansion area, reactor main body upper portion is the larger diameter cylinder two, the top of three-phase separator built-in in cylinder two is connected with exhaust port, cylinder two inner lower portion is equipped with packing degassing sedimentation zone, the upper portion of packing degassing sedimentation zone is equipped with filter screen, the outer periphery of filter screen is equipped with annular overflow weir, annular overflow weir outer is equipped with overflow water outlet;The utility model can realize the self-expansion and fluidization of traditional fixed bed reactor, with higher denitrification load and better load impact resistance, and simple structure, flexible operation, without backwashing system and regular backwashing operation.

Description

[Technical Field]

[0001] This utility model relates to the field of sulfur autotrophic denitrification, specifically a sulfur autotrophic denitrification expanded bed reactor. [Background Technology]

[0002] Sulfur autotrophic denitrification technology mainly adopts a filter bed model, in which sulfur autotrophic granules are filled into a denitrification filter bed to form a fixed-bed bioreactor. Sulfur autotrophic microorganisms grow on the surface of the packing particles, existing in the form of a biofilm. The treated water flows through the packing bed and undergoes a denitrification reaction inside it.

[0003] However, the main problems of the sulfur autotrophic denitrification process in the fixed bed biofilter mode are as follows: (1) the mass transfer efficiency of the biochemical reaction. The fixed bed biofilm method requires a high filtration rate to enhance mass transfer, but it still cannot effectively solve the mass transfer efficiency problem in the near-surface area; (2) uneven water distribution and pressure cause the treated water to flow unevenly into the filter bed, and will cause problems such as fouling and short flow, resulting in a decrease in overall efficiency; (3) the autotrophic denitrification process is a process of consuming alkalinity. The pH gradually decreases along the water flow direction and may be lower than the pH range suitable for the biochemical reaction, resulting in a decrease in overall treatment efficiency; (4) the retention of nitrogen and the accumulation of suspended solids in the influent require regular nitrogen removal and backwashing operations. The filter must be equipped with air washing, water washing and other facilities.

[0004] Therefore, there is an urgent need to develop a sulfur autotrophic denitrification expanded bed reactor to solve the above problems. [Utility Model Content]

[0005] The purpose of this invention is to address the above-mentioned shortcomings by providing a sulfur autotrophic denitrification expanded bed reactor that can achieve self-expansion and fluidization of traditional fixed bed reactors. It has a higher denitrification load and better resistance to load shocks. Moreover, the reactor has a simple structure, flexible operation, and does not require a backwashing system or periodic backwashing operations.

[0006] To achieve the above objectives, a sulfur autotrophic denitrification expanded bed reactor is designed, comprising a reactor body 1, which is composed of upper, middle, and lower parts. The lower part of the reactor body 1 is configured as an inverted cone 4, with a slag discharge port 17 at the bottom. A water inlet pipe 5 is installed in the upper part of the inverted cone 4, connected to a water inlet pipe 18. The middle part of the reactor body 1 is a cylinder, with a support plate 6 installed at the bottom of the inner cavity. A support layer 7 is laid on top of the support plate 6. Above the support layer 7 is a packing filling area 9, and above the packing filling area 9 is a packing expansion area 10. The upper part of the reactor body 1 is a cylinder II with a diameter larger than the middle part. The cylinder II has a three-phase separator 12 inside, and the top of the three-phase separator 12 is connected to an exhaust port 16. The lower part of the cylinder II has a packing degassing and settling area 11, and the upper part of the packing degassing and settling area 11 has a filter screen 13. The outer periphery of the filter screen 13 has an annular overflow weir 14, and the outer periphery of the annular overflow weir 14 has an overflow outlet 15.

[0007] Furthermore, the inlet end of the inlet pipe 18 is connected to the outlet of the inlet pump 3, and the inlet of the inlet pump 3 is connected to the feed tank 2 through a pipe. The denitrification wastewater in the feed tank 2 is pumped into the inverted cone 4 at the bottom of the reactor body 1 by the inlet pump 3 through the inlet pipe 18.

[0008] Furthermore, the water inlet and distribution pipes 5 are arranged in a circular or grid pattern, the water inlet and distribution pipes 5 are fixed under the support plate 6, and the water inlet and distribution pipes 5 are provided with water passage holes of 0.5-2mm.

[0009] Furthermore, the support plate 6 is fixed to the lower edge of the inner cavity of the cylindrical body in the middle of the reactor body 1, and the support plate 6 has circular water passage holes of 0.5-2mm distributed on it.

[0010] Furthermore, the supporting layer 7 is, but is not limited to, any of pebbles or gravel with a particle size of 5-20 mm and a thickness of 10-20 cm.

[0011] Furthermore, the packing zone 9 occupies 20%-70% of the central area of ​​the reactor body 1, and the packing zone 9 is filled with self-expanding composite biological denitrification packing 8.

[0012] Furthermore, the particle size of the self-expanding composite biological denitrification packing 8 is 0.1-0.5 mm, and the internal porosity of the self-expanding composite biological denitrification packing 8 is greater than 50%.

[0013] Furthermore, the three-phase separator 12 has a conical structure, and the opening diameter of the three-phase separator 12 is larger than the diameter of the cylinder in the middle of the reactor body 1. The three-phase separator 12 is used to collect the rising particulate packing.

[0014] Compared with the prior art, this invention introduces water through a bottom pipe in the reactor, with a support layer at a certain distance from the bottom. A layer of pebbles is placed on top of the support layer, and on top of the pebbles is a self-expanding, self-saturating sulfur-based packing material. The upper diameter of the reactor is enlarged, and an overflow outlet is provided. Throughout the reactor, nitrogen gas generated by denitrification causes nitrogen bubbles to adhere to the internal pores and surface of the particles, leading to particle rise and the formation of an expanded bed. This solves the problem of traditional fixed-bed denitrification filters requiring air-water washing, saving on the need for an air distribution system, blower, backwash pump, etc., and simplifying the reactor structure. Furthermore, this invention enhances the mass transfer process, improves biochemical reaction efficiency, eliminates the need for periodic backwashing and nitrogen removal operations, and avoids dead zones.

[0015] In summary, this novel reactor does not require a circulating pump or airlift aeration to provide additional power. Utilizing the self-expanding properties of the self-expanding bed composite biological denitrification packing, it achieves self-expansion and fluidization, similar to a traditional fixed-bed reactor. It has a higher denitrification load and better resistance to load shocks. Furthermore, the reactor has a simple structure, flexible operation, and does not require a backwashing system or periodic backwashing operations. It can achieve rapid denitrification for different water qualities and is worthy of widespread application. [Image Description]

[0016] Figure 1 This is a schematic diagram of the structure of this utility model;

[0017] In the diagram: 1. Reactor body; 2. Feed tank; 3. Water pump; 4. Inverted cone; 5. Water inlet distribution pipe; 6. Support plate; 7. Support layer; 8. Self-expanding composite biological denitrification packing; 9. Packing filling zone; 10. Packing expansion zone; 11. Packing degassing and settling zone; 12. Three-phase separator; 13. Filter screen; 14. Annular overflow weir; 15. Overflow outlet; 16. Exhaust port; 17. Slag discharge port; 18. Water inlet pipe. [Detailed Implementation]

[0018] As attached Figure 1As shown, this utility model provides a sulfur autotrophic denitrification expanded bed reactor, including a reactor body 1, which is composed of upper, middle and lower parts; the lower part of the reactor body 1 is set as an inverted cone 4, and the bottom of the inverted cone 4 is provided with a slag discharge port 17. The upper part of the inverted cone 4 is provided with a water inlet pipe 5, which is connected to a water inlet pipe 18. The water inlet end of the water inlet pipe 18 is connected to the outlet of a water inlet pump 3. The water inlet of the water inlet pump 3 is connected to a feed tank 2 through a pipe. The denitrification wastewater in the feed tank 2 is pumped into the inverted cone 4 at the lower part of the reactor body 1 by the water inlet pump 3 through the water inlet pipe 18; the middle part of the reactor body 1 is a cylinder, and the bottom of the inner cavity of the cylinder is provided with a support plate 6. The support plate 6 is located on the top of the cylinder. A support layer 7 is laid out, and a packing filling area 9 is provided above the support layer 7. A packing expansion area 10 is provided above the packing filling area 9. The upper part of the reactor body 1 is a cylinder II with a diameter larger than that of the middle part. A packing degassing and settling area 11 is provided in the lower part of the cylinder II. A filter screen 13 is provided above the packing degassing and settling area 11. An annular overflow weir 14 is provided on the outer periphery of the filter screen 13. An overflow outlet 15 is provided outside the annular overflow weir 14. A three-phase separator 12 is built into the cylinder II. An exhaust port 16 is connected to the top of the three-phase separator 12. The three-phase separator 12 has a conical structure. The opening diameter of the three-phase separator 12 is larger than the diameter of the cylinder in the middle of the reactor body 1. The three-phase separator 12 is used to collect the rising particulate packing.

[0019] The inlet and distribution pipes 5 are arranged in a circular or grid pattern and are fixed below the support plate 6. Each inlet and distribution pipe has 0.5-2mm water passage holes. The support plate 6 is fixed to the lower edge of the cylindrical inner cavity in the middle of the reactor body 1 and also has 0.5-2mm circular water passage holes. The support layer 7 is, but is not limited to, any type of pebble or gravel with a particle size of 5-20mm and a thickness of 10-20cm. The packing area 9 occupies 20%-70% of the middle area of ​​the reactor body 1. The packing area 9 is filled with self-expanding composite biological denitrification packing 8, which has a particle size of 0.1-0.5mm and an internal porosity greater than 50%.

[0020] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0021] An autotrophic denitrification expanded bed reactor for nitrogen removal includes a reactor body, a raw water tank, a water distribution device, a support layer, a packing filling zone, a packing expansion zone, a packing degassing and settling zone, a three-phase separator, a filter screen, an effluent weir, an effluent outlet, an exhaust outlet, and a slag discharge outlet. This reactor requires no additional power from a circulating pump or airlift aeration. Utilizing the self-expanding properties of the self-expanding bed composite biological nitrogen removal packing, it achieves self-expansion and fluidization, unlike traditional fixed-bed reactors, resulting in higher nitrogen removal loads and better resistance to load shocks. Furthermore, the reactor has a simple structure and flexible operation, eliminating the need for a backwashing system and periodic backwashing operations, and can achieve rapid nitrogen removal for different water qualities. Specifically, this autotrophic denitrification expanded bed reactor for nitrogen removal includes a reactor body 1, which consists of upper, middle, and lower sections.

[0022] (1) The bottom of the reactor is an inverted cone structure, which has the function of collecting sedimentation zone, collecting suspended solids, object impurities, etc. in the sedimentation wastewater, and periodically discharging them from the bottom slag outlet 17; the water inlet distribution pipe 5 is located on the upper part of the bottom inverted cone, distributed in a circular or grid pattern, and fixed below the support plate 6, with 0.5-2mm water passage holes on the water distribution pipe; the water inlet distribution pipe 5 is connected to the water inlet pipe 18; the denitrification wastewater in the feed tank 2 is pumped into the bottom of the reactor by the water inlet pump 3 through the water inlet pipe 18.

[0023] (2) The middle part of the reactor is a circular structure, which is the main area for sulfur autotrophic denitrification and nitrogen removal reaction; the bottom has a support plate 6, which is fixed to the lower edge of the inner cavity of the reactor cylinder. The support plate has a circular water passage hole of 0.5-2mm; a support layer 7 is laid on the support plate 6, which is 10-20cm thick with pebbles, gravel (particle size 5-20mm), etc.; the upper part of the support layer 7 is the packing filling area, accounting for 20%-70% of the middle area; the remaining part of the upper part is the packing expansion area 10.

[0024] (3) The upper part of the reactor is a circular structure with a larger diameter, which is connected to the middle part of the reactor and has a lower surface hydraulic load. It is the packing degassing and settling zone 11. A conical three-phase separator 12 is built in, and its opening diameter is larger than the diameter of the middle part of the reactor to collect the rising particle packing. The three-phase separator is connected to the exhaust port 16. There is a filter screen 13 at the top to intercept the particles flowing out with the water. An annular overflow weir 14 is provided, and an overflow outlet 15 is provided outside the annular overflow weir.

[0025] This invention relates to a self-expanding composite biological denitrification packing material 8, which includes a core component that forms the basis for autotrophic denitrification. The core component is composed of the following raw materials by weight: 50-90 parts elemental sulfur, 5-10 parts carbon powder, and 10-30 parts pH buffer. The internal porous structure provides a larger attachment surface for autotrophic denitrifying bacteria, increasing the reaction area for denitrification and providing a suitable anoxic environment for nitrogen retention during denitrification. An autotrophic denitrifying bacteria biofilm grows on the inner and outer surfaces of the packing particles. The particle size of the packing is 0.1-0.5 mm, and the internal porosity is greater than 50%.

[0026] The overall structure of this reactor conforms to the characteristics of an anaerobic reactor. It has a bottom pipe for water inlet and is equipped with a distributor. A support layer is located at a certain distance from the bottom, and pebbles with a particle size of 10-20 mm and a thickness of 10 cm are placed on top of the pebbles. Sulfate autotrophic packing material with self-expansion is placed on the pebbles. The upper diameter of the reactor is enlarged and there is an overflow outlet. A bubble detacher collects the packing particles that rise to the liquid surface with the bubbles. The bubbles detach from the particles, and the particles fall. The top of the bubble detacher is an exhaust port. In the entire reactor, nitrogen gas is generated due to denitrification. Nitrogen bubbles are attached to the internal pores and surface of the particles, causing the particles to rise and form an expanded bed state.

[0027] This invention can enhance the mass transfer process, improve the efficiency of biochemical reaction, and solve the problem that traditional fixed-bed denitrification filters need to be equipped with air and water washing. It saves the gas distribution system, blower, backwash water pump, etc., simplifies the reactor structure, and eliminates the need for regular backwashing, nitrogen removal and other operations, and does not produce dead zones.

[0028] The contents not described in detail in this specification are existing technologies known to those skilled in the art. The standard parts used can be purchased from the market, and the irregular parts can be customized according to the description and drawings. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the existing technology. The machinery, parts and equipment adopt conventional models in the existing technology, and the circuit connection adopts conventional connection methods in the existing technology, which will not be described in detail here.

[0029] This utility model is not limited to the above-described embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of this utility model shall be considered equivalent substitutions and shall be included within the protection scope of this utility model.

Claims

1. A sulfur-autotrophic denitrification expanded bed reactor, characterized in that: The reactor includes a reactor body (1), which is composed of three parts: upper, middle, and lower. The lower part of the reactor body (1) is set as an inverted cone (4), and the bottom of the inverted cone (4) is provided with a slag discharge port (17). The upper part of the inverted cone (4) is provided with a water inlet pipe (5), which is connected to a water inlet pipe (18). The middle part of the reactor body (1) is a cylinder. The bottom of the inner cavity of the cylinder is provided with a support plate (6), and a support layer (7) is laid on the support plate (6). A packing material is provided above the support layer (7). The packing area (9) is above the packing expansion area (10). The upper part of the reactor body (1) is a cylinder II with a diameter greater than that of the middle part. The cylinder II has a three-phase separator (12) inside. The top of the three-phase separator (12) is connected to an exhaust port (16). The lower part of the cylinder II is provided with a packing degassing and settling area (11). The upper part of the packing degassing and settling area (11) is provided with a filter screen (13). The filter screen (13) is provided with an annular overflow weir (14) on its outer periphery. The annular overflow weir (14) is provided with an overflow outlet (15) outside.

2. The sulfur autotrophic denitrification expanded bed reactor as described in claim 1, characterized in that: The inlet end of the inlet pipe (18) is connected to the outlet of the inlet pump (3). The inlet of the inlet pump (3) is connected to the feed tank (2) through a pipe. The denitrification wastewater in the feed tank (2) is pumped by the inlet pump (3) through the inlet pipe (18) into the inverted cone (4) at the bottom of the reactor body (1).

3. The sulfur autotrophic denitrification expanded bed reactor as described in claim 1, characterized in that: The water inlet and distribution pipes (5) are arranged in a circular or grid pattern. The water inlet and distribution pipes (5) are fixed under the support plate (6). The water inlet and distribution pipes (5) have water passage holes of 0.5-2mm.

4. The sulfur autotrophic denitrification expanded bed reactor as described in claim 1, characterized in that: The support plate (6) is fixed to the lower edge of the inner cavity of the cylindrical body in the middle of the reactor body (1), and the support plate (6) has circular water passage holes of 0.5-2mm distributed on it.

5. The sulfur autotrophic denitrification expanded bed reactor as described in claim 1, characterized in that: The supporting layer (7) is, but is not limited to, any of pebbles or gravel with a particle size of 5-20 mm and a thickness of 10-20 cm.

6. The sulfur autotrophic denitrification expanded bed reactor as described in claim 1, characterized in that: The packing zone (9) occupies 20%-70% of the central area of ​​the reactor body (1), and the packing zone (9) is filled with self-expanding composite biological denitrification packing (8).

7. The sulfur autotrophic denitrification expanded bed reactor as described in claim 6, characterized in that: The particle size of the self-expanding composite biological denitrification packing (8) is 0.1-0.5 mm, and the internal porosity of the self-expanding composite biological denitrification packing (8) is greater than 50%.

8. The sulfur autotrophic denitrification expanded bed reactor as described in claim 1, characterized in that: The three-phase separator (12) has a conical structure and the opening diameter of the three-phase separator (12) is larger than the diameter of the cylinder in the middle of the reactor body (1). The three-phase separator (12) is used to collect the rising particulate packing.

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