WO2018040753A1

WO2018040753A1 - Double-biomembrane sewage treatment system and method

Info

Publication number: WO2018040753A1
Application number: PCT/CN2017/092589
Authority: WO
Inventors: 刘川; 刘晓川
Original assignee: 武汉东川自来水科技开发有限公司
Priority date: 2016-08-29
Filing date: 2017-07-12
Publication date: 2018-03-08
Also published as: CN106348437A; CN106348437B

Abstract

A double-biomembrane sewage treatment system and amethod. The system comprises a pre-aeration adjusting tank (1), a vertical three-phase fluidized bed (2), a two-stage biological aerated filter (3), and a middle water tank (4) which are connected in sequence. The vertical three-phase fluidized bed (2) comprises: a reaction cylinder (21) with the lower end being connected to the pre-aeration adjusting tank (1); a flow guiding cylinder (22) provided in the reaction cylinder (21); an aeration mechanism (23) that comprises an aeration fan (231) and is provided with multiple aeration discs (232) and aeration pipes (233); and a water outlet mechanism (24) provided right above the flow guiding cylinder (22) and connected to the two-stage biological aerated filter (3). Pre-aeration adjustment, internal-circulation biochemical treatment, and two-stage aeration biochemical treatment are performed successively. According to the system, on one hand, the flow guiding cylinder (22) and the aeration mechanism (23) matching each other are provided in the vertical three-phase fluidized bed (2) to form an aerobic zone inside the flow guiding cylinder (22) and an anaerobic zone and a facultative zone outside the flow guiding cylinder (22), so that a suspended filler is circulated inside and outside the flow guiding cylinder (22), and then nitrification and de-nitrification performed alternately and circularly; on the other hand, secondary biomembrane treatment is performed by means of the two-stage biological aerated filter (3) to improve the sewage treatment effect.

Description

Double biofilm sewage treatment system and treatment method

Technical field

The invention relates to sewage treatment technology, in particular to a double biofilm sewage treatment system and a treatment method.

Background technique

Water is the source of human life and the basis of survival. With the development of industrial and agricultural production, the water environment problem has become more and more serious, and the water quality problem has seriously affected the normal life of our human beings. Therefore, effective sewage purification technologies must be sought to achieve sustainable use of water resources.

In recent years, many mature and effective sewage treatment methods have been established, such as the activated sludge method in domestic large city sewage treatment plants. At the same time as the application of activated sludge process, AB method, A/O method, A2/O method, CASS method, SBR method, oxidation ditch method, stable pond method, land treatment method, etc. are also obtained in the construction of sewage treatment plant. application. The advantage of sewage treatment technology based on activated sludge process is that the sewage has strong adaptability and low construction cost, and the disadvantage is that the operation stability is poor, sludge expansion and sludge loss are easy to occur, and the separation effect is not ideal. The activated sludge process mainly uses the biological activity of microorganisms to remove pollutants such as COD, ammonia nitrogen and phosphorus in the sewage. In order to achieve the desired sewage treatment effect, various bacterial communities need to work together under different conditions, such as: heterotrophic bacteria oxidative decomposition of organic matter under aerobic conditions, autotrophic bacteria (nitrifying bacteria) in aerobic Under the condition of oxidation of ammonia nitrogen (nitrification reaction), heterotrophic bacteria use anaerobic conditions for the reduction of nitrite/nitrate by organic matter (denitrification reaction). It is generally believed that the nitrification process is an important process in the whole process of ammonia nitrogen degradation, and the process is slow and difficult. Mainly because nitrifying bacteria are autotrophic bacteria, including nitrosomonas and nitrobacter. Both types of bacteria are obligate aerobic bacteria. Oxygen is used as the final electron acceptor in the oxidation process, and inorganic carbon (usually carbon dioxide) is used as the sole source of energy. Therefore, the nitrifying bacteria have a long metabolic time, the reproduction is very slow, and the growth environment is harsh. Some common nitrite species take an average of 26 hours to multiply, while the nitric acid species have a longer reproductive cycle, which takes an average of 60 hours. Can multiply. Therefore, under many conditions, it is impossible to gain an advantage in the growth competition with heterotrophic microorganisms.

However, the biofilm process using microorganisms for sewage treatment in the same manner as the activated sludge method does not have the above disadvantages, but the conventional biofilm method has the drawbacks of low sewage treatment efficiency and high energy consumption.

Summary of the invention

The object of the present invention is to overcome the above technical deficiencies, and to provide a dual biofilm sewage treatment system and a treatment method thereof, which solve the technical problem of low efficiency and high energy consumption of the biofilm method in the prior art.

In order to achieve the above technical purpose, the technical solution of the present invention provides a dual biofilm sewage treatment system, which comprises a pre-aeration regulating tank, a vertical three-phase fluidized bed, a second-stage aerated biological filter and an intermediate pool connected in sequence. The vertical three-phase fluidized bed includes:

a reaction cartridge vertically disposed, wherein a reaction chamber having a lower end connected to the pre-aeration conditioning tank is formed in the reaction cylinder;

a guide tube coaxially built into the reaction chamber;

An aeration mechanism comprising an aeration fan, a plurality of aeration disks disposed directly below the flow guide tube, and an aeration tube connecting the aeration fan and the aeration disk;

The water outlet mechanism is disposed coaxially above the draft tube, and the water outlet end of the water outlet mechanism is connected to the water inlet end of the second aerated biological filter.

Preferably, the water discharge mechanism comprises an outer rectifying cylinder, an inner rectifying cylinder, a carrier separator and an overflow weir, and the inner rectifying cylinder is coaxially built in the outer rectifying cylinder and forms a rectifying chamber with the outer rectifying cylinder, An outlet chamber communicating with the lower end of the rectifying chamber is formed between the outer rectifying cylinder and the reaction cylinder, and a water outlet end of the carrier separator is in communication with the rectifying chamber, and one end of the overflow weir and the water outlet chamber The upper end is connected and the other end is connected to the water inlet end of the second aerated biological filter.

Preferably, the vertical three-phase fluidized bed further comprises a conical cover whose outer diameter gradually increases from top to bottom, the upper end of the conical cover is connected to the inner rectifying cylinder, and the upper end of the guiding tube is extended Inside the conical cover.

Preferably, the carrier separator is plural and uniformly arranged circumferentially along the inner wall of the inner rectifying cylinder, and each of the carrier separators comprises:

a separation cylinder, the separation cylinder sidewall is provided with a plurality of separation holes;

a water discharge cylinder built in the separation cylinder, a separation cavity is formed between the water discharge cylinder and the separation cylinder, and one end of the water discharge cylinder passes through the separation cylinder and communicates with the rectification chamber, and the other end is along The separation cylinder extends axially and forms a gap with the separation chamber at the end of the separation cylinder.

Preferably, the vertical three-phase fluidized bed further includes a first backwashing mechanism, the first backwashing mechanism includes a first backwash pump connected to the intermediate pool at a water inlet end, and the first The backwash pump is connected with an annular backwashing main pipe and a plurality of backwashing pipes, each of which has one end communicating with the backwashing main pipe and the other end communicating with the separating cavity.

Preferably, the second aerated biological filter comprises a first aerated biological filter, a second aerated biological filter and an overflow pipe, and the water inlet end and the overflow of the first aerated biological filter The outlet end of the flowing water is connected, one end of the overflow pipe is connected to the upper end of the first aerated biological filter, and the other end is connected to the water inlet end of the second aerated biological filter.

Preferably, the second aerated biological filter comprises a second backwashing mechanism, and the second backwashing mechanism comprises a first connected to the lower ends of the first aerated biological filter and the second aerated biological filter respectively. a backwashing inlet pipe and a second backwashing inlet pipe, respectively disposed at the upper end of the first aerated biological filter and the second aerated biological filter, and a second backwashing outlet pipe, A backwashing inlet pipe and a second backwashing inlet pipe are both connected to the intermediate pool at one end, and the inlet end of the first backwashing outlet pipe is provided with a plurality of first communicating with the first aerated biological filter A water outlet is provided, and the water inlet end of the second backwashing water pipe is provided with a plurality of second water outlets communicating with the second aerated biological filter.

Preferably, the second backwashing mechanism further includes a transition pool connected to the water outlet end of the first backwash outlet pipe and the second backwash outlet pipe, and a drain pipe and a return pipe connected to the bottom of the transition pool. The return pipe is lower than the drain pipe and the water outlet end of the return pipe is connected to the top end of the pre-aeration tank.

At the same time, the present invention also provides a double biofilm sewage treatment method, comprising the following steps:

(1) Pre-aeration treatment through the pre-aeration tank and adjusting the pH, water quality and water volume of the sewage;

(2) The wastewater treated by the step (1) is entered from the bottom of the reaction chamber of the vertical three-phase fluidized bed, the suspended filler is added and the aeration device is turned on, so that the suspended filler inside and outside the guide tube is circulated;

(3) The sewage treated in the step (2) is subjected to biochemical treatment through a secondary aerated biological filter.

Preferably, the biochemical treatment of the step (3) comprises the first-stage treatment of the sewage into the first biological aerated filter and the overflow of the sewage treated by the first biological biological filter to the second biological biological filter. The secondary treatment in the tank, in the primary treatment and the secondary treatment, respectively aerating the first aerated biological filter and the second aerated biological filter to make the oxygen in the second biological filter The concentration is greater than the oxygen concentration in the second aerated biological filter.

Compared with the prior art, the present invention provides a matching draft tube and an aeration mechanism in a vertical three-phase fluidized bed to form an aerobic zone in the draft tube, an anaerobic zone outside the draft tube, and In the oxygen zone, the suspended filler is circulated inside and outside the guide tube, and then the nitrification and denitrification alternate reactions are cycled. On the other hand, the secondary aerated biofilter and the secondary biofilm treatment are used to improve the sewage treatment effect.

DRAWINGS

Figure 1 is a schematic view showing the connection structure of the double biofilm sewage treatment system of the present invention;

Figure 2 is an enlarged view of a portion A of Figure 1 of the present invention;

Figure 3 is a schematic structural view of a carrier separator of the present invention;

Figure 4 is a schematic view showing the distribution of the aeration disk of the present invention.

detailed description

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

1 to 4, an embodiment of the present invention provides a dual biofilm sewage treatment system, comprising a pre-aeration conditioning tank, a vertical three-phase fluidized bed, and a second-stage biological aerated filter 3, which are sequentially connected. And an intermediate pool 4, the vertical three-phase fluidized bed 2 comprises:

a reaction cartridge 21 disposed vertically, and a reaction chamber having a lower end connected to the pre-aeration conditioning tank 1 is formed in the reaction cylinder 21;

Coaxial tube 22 coaxially built into the reaction chamber;

The aeration mechanism 23 includes an aeration fan 231, a plurality of aeration discs 232 disposed directly below the draft tube 22, and an aeration tube 233 connecting the aeration fan 231 and the aeration tray 232; and

The water outlet mechanism 24 is disposed coaxially above the draft tube 22, and the water outlet end of the water outlet mechanism 24 is connected to the water inlet end of the secondary aerated biological filter 3.

When sewage treatment, the sewage first enters the pre-aeration conditioning tank 1 for pre-aeration treatment and preliminary oxidation treatment of the sewage, and at the same time adjusts the pH, water quality and water volume of the sewage; the reaction of the vertical three-phase fluidized bed 2 after adjustment The bottom of the cavity is filled with water, and the infill water is simultaneously added to the suspended filler and the aeration mechanism 23 is opened. When the water level in the reaction chamber reaches the inside of the guide tube 22, since the plurality of aeration trays 232 are located directly below the guide tube 22, the aeration is performed. At this time, the gas is only aerated in the gas guiding cylinder 22, and no aeration is performed between the gas guiding cylinder 22 and the reaction cylinder 21, so that an aerobic zone is formed in the gas guiding cylinder 22, and the gas guiding cylinder 22 and the reaction cylinder 21 are An anaerobic zone and a facultative zone are formed to cause nitrification and denitrification reactions respectively inside and outside the guide tube 22; when the water level reaches a certain amount, the guide tube 22 is submerged, and under the action of the aeration disk 232, the guide tube The suspended filler in the 22 moves from bottom to top, and the suspended filler between the guide tube 22 and the reaction cylinder 21 moves from top to bottom, thereby forming a circulating motion of the suspended filler inside and outside the guide tube 22, thereby causing the sewage to alternate. Nitrification and denitrification, which achieve the same reaction The nitrification and denitrification reactions alternately occur in the cylinder 21, which reduces energy consumption, construction cost, and improves sewage treatment efficiency. After the biochemical reaction, the clear liquid located at the upper end of the reaction chamber can enter the second aerated biological filter 3 through the water outlet mechanism 24, and undergo secondary biochemical treatment through the second aerated biological filter 3 to further reduce the COD and ammonia nitrogen content. Among them, in the above-mentioned nitrification and denitrification reaction, with the suspension filler The depth of the biofilm is different, and short-range nitrification and anaerobic ammonium nitridation are formed in the biofilm, thereby further improving the sewage treatment efficiency and the deamination rate of the inside and outside of the guide tube 22 of the present embodiment.

As shown in FIG. 4, in order to increase the cooperative aeration effect of the aeration mechanism 23 and the guide tube 22, a plurality of the aeration discs 232 of the embodiment are arranged in an annular array directly below the guide tube 22. Arranging the plurality of aeration discs 232 in an annular array arrangement can cooperate with the flow guide barrel 22 to promote the upward movement of the suspended packing within the flow guide barrel 22.

Specifically, the water discharge mechanism 24 of the present embodiment includes an outer rectifying cylinder 241, an inner rectifying cylinder 242, a carrier separator 243, and a weir 244. The inner rectifying cylinder 242 is coaxially built into the outer rectifying cylinder 241 and externally. A rectifying chamber is formed between the rectifying cylinders 241, and a water outlet chamber communicating with the lower end of the rectifying chamber is formed between the outer rectifying cylinder 241 and the reaction cylinder 21, and the water outlet end of the carrier separator 243 is The rectifying chamber is in communication, and one end of the weir 244 is connected to the upper end of the water outlet chamber, and the other end is connected to the water inlet end of the second aerated biological filter 3. The vertical three-phase fluidized bed 2 of the present embodiment is intermittently fed with water. After the reaction is completed, since the activated sludge can pass through the carrier separator 243 and enter the rectifying chamber, the carrier separator 243 enters the rectifying chamber. The sludge can be precipitated, while the water entering the water outlet is clarified water, and the clarified water in the outlet chamber can overflow through the overflow weir 244. Among them, when suspended, the suspended filler is easy to collapse due to the absence of water and aeration support, and under the action of gravity, the collapsed suspended fillers collide with each other, causing the biofilm formed on the suspended filler to fall off and regenerate, thereby The next influent wastewater treatment provides conditions.

The carrier separator 243 is provided in the embodiment to facilitate the separation of the suspended filler during the water discharge process, to ensure that the clarified water in the rectifier chamber does not contain the suspended filler, and the loss rate of the suspended filler is reduced, and the cooperation of the outer rectifying cylinder 241 and the inner rectifying cylinder 242 can be reduced. The clarified water in the rectifying chamber is affected by the reaction zone inside and outside the draft tube 22 to ensure the clarity of the clarified water in the rectifying chamber.

As shown in Figure 1, Figure 2, Figure 3. In order to improve the balance of the separation of the carrier separator 243 and the water discharge efficiency, the carrier separator 243 is plural and uniformly arranged circumferentially along the inner wall of the inner rectifying cylinder 242, and each of the carrier separators 243 includes a separation cylinder 243a. And the water discharge cylinder 243b, a plurality of separation holes are disposed on the side wall of the separation cylinder 243a, the water discharge cylinder 243b is built in the separation cylinder 243a and a separation cavity is formed between the separation cylinder 243a, and the water discharge cylinder 243b is worn at one end. The separation cylinder 243a passes through the rectifying chamber, and the other end extends axially along the separation cylinder 243a and forms a gap with the separation chamber 243a. That is, the clarified water enters the rectifying chamber from the separation hole, and enters the water discharge cylinder 243b through the gap between the end of the separation cylinder 243a and the water discharge cylinder 243b, and then enters the rectifying chamber and overflows through the overflow weir 244.

Each of the separation holes in the embodiment is an arc-shaped hole arranged circumferentially along the separation cylinder 243a, and the plurality of separation holes are evenly arranged along the axial direction of the separation cylinder 243a, and the arc hole can be used to improve The water discharge effect of the separation cylinder 243a rate.

The vertical three-phase fluidized bed 2 of the present embodiment further includes a tapered cover 25 whose outer diameter gradually increases from top to bottom, and the upper end of the tapered cover 25 is connected to the inner rectifying cylinder 242, and the guide The upper end of the flow tube 22 extends into the conical cover 25. Further, there is a gap between the outer edge of the tapered cover 25 and the inner wall of the reaction tube 21. During the drowning, the sewage enters the rectifying chamber from the inner rectifying cylinder 242 through the carrier separator 243, and the sludge entering the rectifying chamber moves downward along the outer wall of the conical cover 25 to between the guiding tube 22 and the reaction tube 21. And the suspended filler which is moved into the inner cone cover 25 by the gap at the time of aeration flows to the upper surface of the cone cover 25 with the sludge, so that a flocculation clear layer is formed on the upper surface of the cone cover 25, and the flocculation is clarified. The layer can be subjected to a secondary reaction with the effluent-sewing water, which is advantageous for improving the reaction efficiency.

In order to improve the sewage treatment effect and avoid equipment clogging, the vertical three-phase fluidized bed 2 further includes a first backwashing mechanism 26, and the first backwashing mechanism 26 includes a water inlet end connected to the intermediate pool 4. a first backwashing pump 261, an annular backwashing main pipe 262 connected to the first backwashing pump 261, and a plurality of backwashing pipes 263, each of the backwashing pipes 263 having one end and the backwashing The main pipe 262 is in communication and the other end is in communication with the separation chamber. In specific use, the first backwash pump 261 can be turned on for a certain period of time to backwash the carrier separator 243 to avoid clogging of the carrier separator 243.

As shown in FIG. 1 , the second aerated biological filter 3 of the embodiment includes a first aerated biological filter 31, a second aerated biological filter 32 and an overflow pipe 33, and the first aerated organism The water inlet end of the filter tank 31 is connected to the water outlet end of the overflow weir 244, and one end of the overflow pipe 33 is connected to the upper end of the first aerated biological filter tank 31, and the other end is connected to the second aerated organism. The water inlet end of the filter tank 32 is connected. The treatment process is as follows: the sewage first enters the first aerated biological filter 31 for primary treatment, and after the first treatment, overflows from the overflow pipe 33 connected to the upper end of the first aerated biological filter 31 to the second exposure. The secondary biological treatment is carried out in the gas biological filter 32. In order to improve the processing efficiency of the primary treatment and the secondary treatment, the present embodiment increases the aeration power in the first biological aerated filter 31, thereby improving the first biological filtration. The concentration of oxygen in the pool 31 is such that the concentration of oxygen in the first aerated biofilter 31 is greater than the concentration of oxygen in the second aerated biofilter 32. Increasing the concentration of oxygen in the first aerated biofilter 31 may be advantageous. The dominant strains that easily remove COD are cultured, thereby promoting the removal efficiency of COD; while the second aerated biological filter 32 is relatively set to a lower oxygen concentration, which is advantageous for cultivating the dominant strains for removing ammonia nitrogen to promote the removal of ammonia nitrogen. effectiveness.

The oxygen concentration in the first aerated biological filter 31 and the second aerated biological filter 32 in the present embodiment can be controlled as needed, thereby separately controlling the culture of the first aerated biological filter 31 and the second aerated organism. The dominant species of COD and ammonia nitrogen in the filter tank 32 improves the COD and ammonia nitrogen removal efficiency as a whole.

The second aeration biological filter 3 includes a second backwashing mechanism 34, and the second backwashing mechanism 34 includes a first aerated biological filter 31 and a second aerated biological filter 32, respectively. The first backwash connection of the lower end The water pipe 341 and the second backwashing water inlet pipe 342 are disposed at the upper end of the first aerated biological filter 31 and the second aerated biological filter 32, respectively, and the first backwashing water outlet pipe 343 and the second backwashing water outlet pipe 344. The first backwashing inlet pipe 341 and the second backwashing inlet pipe 342 are both connected to the intermediate pool 4 at one end, and specifically connected to the second backwashing water pump 340 built in the intermediate pool 4, the first backwashing The water inlet end of the water pipe 343 is provided with a plurality of first water outlets 343a communicating with the first aerated biological filter 31, and the water inlet end of the second backwash water outlet pipe 344 is provided with the second aeration organism A plurality of second outlets 344a are connected to the filter tank 32. During the biochemical treatment of the wastewater, the backwashing may be periodically performed to ensure the processing efficiency of the second aerated biological filter 3, and the first backwashing outlet pipe 343 and the second backwashing outlet pipe 344 of the present embodiment are respectively set to be first. The outlet tank 343a and the second outlet tank 344a form overflow water, thereby reducing transportation energy consumption.

The plurality of the first water outlets 343a are evenly arranged along the longitudinal direction of the first backwash water outlet pipe 343, and the plurality of the second water outlet water tanks 344a are evenly distributed along the length of the second backwash water outlet pipe 344. Arranged to increase the overflow area and promote overflow efficiency.

In the initial stage of the backwashing water, the effluent contains sewage and a small amount of sludge, and forms a turbid state. In order to avoid turbid water discharge, the second backwashing mechanism 34 further includes a first backwashing water outlet 343 and a second a transition tank 345 connected to the outlet end of the backwash outlet pipe 344 and a drain pipe 346 and a return pipe 347 communicating with the bottom of the transition tank 345, the return pipe 347 being lower than the drain pipe 346 and the return pipe 347 The water outlet end is connected to the top end of the pre-aeration conditioning tank 1. When the water is backwashed, it can enter the transition tank 345, and the turbid water can be directly returned to the pre-aeration tank 1 through the return pipe 347 at the bottom of the transition tank 345 for subsequent re-treatment, and when the backwash water is clarified water The return valve on the return pipe 347 can be closed. Since the drain pipe 346 is higher than the return pipe 347, when the clarified water accumulated in the transition pool 345 is higher than the drain pipe 346, the water can be automatically discharged through the drain pipe 346.

In this embodiment, the connection of the secondary aerated biological filter 3 through the overflow pipe 33 and the setting of the second backwashing mechanism 34 make the water discharge overflow, which reduces the energy consumption for driving the sewage flow.

Further, the second backwashing mechanism 34 of the embodiment further includes a three-way valve 348 and a gas-barrier failure well 349. The two water inlet ends of the three-way valve 348 are respectively associated with the first backwashing water outlet 343 and the first The two backwashing water outlet pipes 344 are connected, and the water outlet end of the three-way valve 348 communicates with the upper end of the transition pool 345 through the gas-resistance destruction well 349, and a gas-resistance well 349 is disposed to avoid the formation of air resistance during backwashing. Therefore, the recoil water can flow smoothly.

The sewage treatment process of the double biofilm sewage treatment system of the embodiment is as follows: first, the sewage enters the pre-aeration conditioning tank for pre-aeration treatment and preliminary oxidation treatment of the sewage, and at the same time adjusts the pH, water quality and water volume of the sewage; The water is fed from the bottom of the reaction chamber of the vertical three-phase fluidized bed, and the suspended water is added to the influent water to start the aeration mechanism. When the water level in the reaction chamber is in the guide tube, the plurality of aeration discs are located in the guide tube. Below, so when aerating, The gas is only aerated in the guiding tube, and no aeration is performed between the guiding tube and the reaction tube, so that an aerobic zone is formed in the guiding tube, and an anaerobic zone and facultative gas are formed between the guiding tube and the reaction tube. Zone, the nitrification and denitrification reactions are carried out inside and outside the guide tube respectively; when the water level reaches a certain amount, the guide tube is submerged, and under the action of the aeration disc, the suspended filler in the guide tube moves from bottom to top, and the guide The suspended filler between the flow tube and the reaction tube moves from top to bottom, thereby forming a cyclic movement of the suspended filler inside and outside the guide tube, so that the sewage is alternately subjected to nitrification and denitrification reaction, which realizes nitrification in the same reaction tube, The alternating denitrification reaction reduces the energy consumption and construction cost and improves the sewage treatment efficiency; the clarification liquid located at the upper end of the reaction chamber after the biochemical reaction can enter the second aerated biological filter through the water outlet mechanism, and pass through the second The aerated biological filter is subjected to secondary biochemical treatment, and the sewage first enters the first aerated biological filter for primary treatment, and after the primary treatment, the overflow pipe connected to the upper end of the first aerated biological filter Flowing into the second aerated biological filter for secondary treatment, in order to improve the treatment efficiency of the primary treatment and the secondary treatment, the present embodiment increases the aeration power in the first biological aerated filter, thereby improving the first exposure. The oxygen concentration in the gas biological filter makes the oxygen concentration in the first aerated biological filter larger than the oxygen concentration in the second biological filter, and increasing the oxygen concentration in the first biological filter can facilitate the cultivation. The dominant species of COD is easily removed, thereby promoting the removal efficiency of COD; while the second aerated biological filter is relatively set to a lower oxygen concentration, which is advantageous for cultivating the dominant species for removing ammonia nitrogen to promote the removal efficiency of ammonia nitrogen. Among them, in the process of nitrification and denitrification of the vertical three-phase fluidized bed, short-distance nitrification and anaerobic ammonium nitridation are formed in the biofilm as the depth of the biofilm of the suspended filler is different, thereby further improving the diversion of the present embodiment. Sewage treatment efficiency and deamination rate inside and outside the cylinder.

The specific embodiments of the invention described above are not intended to limit the scope of the invention. Any other various changes and modifications made in accordance with the technical idea of the present invention are intended to be included within the scope of the appended claims.

Claims

A dual biofilm sewage treatment system, comprising: a pre-aeration regulating tank, a vertical three-phase fluidized bed, a second aerated biological filter and an intermediate pool connected in sequence, wherein the vertical three-phase fluidized bed comprises :

a reaction cartridge vertically disposed, wherein a reaction chamber having a lower end connected to the pre-aeration conditioning tank is formed in the reaction cylinder;

a guide tube coaxially built into the reaction chamber;

An aeration mechanism comprising an aeration fan, a plurality of aeration disks disposed directly below the flow guide tube, and an aeration tube connecting the aeration fan and the aeration disk;

The water outlet mechanism is disposed coaxially above the draft tube, and the water outlet end of the water outlet mechanism is connected to the water inlet end of the second aerated biological filter.
The dual biofilm sewage treatment system according to claim 1, wherein the water discharge mechanism comprises an outer rectifying cylinder, an inner rectifying cylinder, a carrier separator, and an overflow weir, and the inner rectifying cylinder is coaxially built in the outer rectifying Forming a rectifying chamber between the cylinder and the outer rectifying cylinder, a water outlet chamber communicating with the lower end of the rectifying chamber is formed between the outer rectifying cylinder and the reaction cylinder, and the water outlet end of the carrier separator is The rectifying chamber is in communication, and one end of the weir is connected to the upper end of the water outlet chamber, and the other end is connected to the water inlet end of the second aerated biological filter.
The dual biofilm sewage treatment system according to claim 2, wherein said vertical three-phase fluidized bed further comprises a conical cover whose outer diameter gradually increases from top to bottom, and an upper end of said conical cover Connected to the inner rectifying cylinder, the upper end of the draft tube extends into the conical cover.
The dual biofilm sewage treatment system according to claim 3, wherein the carrier separator is plural and uniformly arranged circumferentially along the inner wall of the inner rectifying cylinder, and each of the carrier separators comprises:

a separation cylinder, the separation cylinder sidewall is provided with a plurality of separation holes;

a water discharge cylinder built in the separation cylinder, a separation cavity is formed between the water discharge cylinder and the separation cylinder, and one end of the water discharge cylinder passes through the separation cylinder and communicates with the rectification chamber, and the other end is along The separation cylinder extends axially and forms a gap with the separation chamber at the end of the separation cylinder.
The dual biofilm sewage treatment system according to claim 4, wherein said vertical three-phase fluidized bed further comprises a first backwashing mechanism, said first backwashing mechanism comprising a water inlet end and said middle a first backflushing pump connected to the pool, an annular backwashing main pipe connected to the first backwashing pump, and a plurality of backwashing pipes, each of the backwashing pipes having one end and the backwashing pipe The other end is in communication with the separation chamber.
A dual biofilm sewage treatment system according to any one of claims 1 to 5, wherein said secondary The aerated biological filter comprises a first aerated biological filter, a second aerated biological filter and an overflow pipe, and the inlet end of the first aerated biological filter is connected to the outlet end of the overflow weir, One end of the overflow pipe is connected to the upper end of the first aerated biological filter, and the other end is connected to the water inlet end of the second aerated biological filter.
The dual biofilm sewage treatment system according to claim 6, wherein the secondary aeration biological filter comprises a second backwashing mechanism, and the second backwashing mechanism comprises the first aeration respectively The first backwashing inlet pipe and the second backwashing inlet pipe connected to the lower end of the biological filter and the second aerated biological filter are respectively disposed at the upper ends of the first aerated biological filter and the second aerated biological filter a first backwashing outlet pipe and a second backwashing outlet pipe, wherein the first backwashing inlet pipe and the second backwashing inlet pipe are both connected to the intermediate pool, and the inlet end of the first backwashing outlet pipe is provided with a plurality of first outlets communicating with the first aerated biological filter, and a water inlet end of the second backwashing outlet is provided with a plurality of second outlets in communication with the second aerated biological filter.
The dual biofilm sewage treatment system according to claim 7, wherein said second backwashing mechanism further comprises a transition to the outlet end of said first backwash outlet pipe and said second backwash outlet pipe a pool and a drain pipe and a return pipe communicating with the bottom of the transition pool, the return pipe being lower than the drain pipe and the water outlet end of the return pipe being connected to the top end of the pre-aeration regulating tank.
A double biofilm sewage treatment method, comprising the following steps:

(1) Pre-aeration treatment through the pre-aeration tank and adjusting the pH, water quality and water volume of the sewage;

(2) The wastewater treated by the step (1) is entered from the bottom of the reaction chamber of the vertical three-phase fluidized bed, the suspended filler is added and the aeration device is turned on, so that the suspended filler inside and outside the guide tube is circulated;

(3) The sewage treated in the step (2) is subjected to biochemical treatment through a secondary aerated biological filter.
The dual biofilm sewage treatment method according to claim 9, wherein the biochemical treatment of the step (3) comprises the first treatment of the sewage into the first biological aerated filter and the first aeration organism. The sewage treated by the filter overflows to the secondary treatment in the second biological aerated filter, and in the primary treatment and the secondary treatment, the first aerated biological filter and the second aerated biological filter respectively The aeration is performed such that the concentration of oxygen in the second aerated biological filter is greater than the concentration of oxygen in the second aerated biological filter.