Circulating oxygen control enhanced biochemical sewage treatment system

Abstract

The utility model provides a circulating oxygen control enhanced biochemical sewage treatment system. The circulating type oxygen control enhanced biochemical sewage treatment system comprises a pool body, a mixing area, a screening area, an enhanced biochemical area, a selection area, a circulating area, a mud-water separation area and a backflow area are sequentially arranged in the pool body in a communicating mode, and a sewage inlet is formed in the mixing area. The screening area, the enhanced biochemical area and the selection area are respectively provided with an aeration device and a dissolved oxygen meter to control the dissolved oxygen concentration, the circulation area is provided with an air lifting and pushing device, the sludge-water separation area is provided with a filler layer, a water outlet and a sludge outlet, the sludge outlet is communicated with the backflow area, and the backflow area is communicated with the mixing area to enable at least part of sludge to flow back to the mixing area. The system disclosed by the utility model can be used for removing different pollutants in the same pool body and in the same microbial environment, and has the advantages of shortening the treatment flow, improving the treatment effect, saving the operation cost and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of sewage treatment, in particular to a circulating oxygen-controlled enhanced biochemical sewage treatment system. Background Art

[0002] Biochemical treatment of sewage belongs to secondary treatment, which is mainly aimed at removing non-settled suspended solids and soluble biodegradable organic matter. It can be divided into biofilm method and activated sludge method. The activated sludge method is an aerobic biological treatment method for sewage. Under artificial oxygenation conditions, sewage and various microbial communities are continuously mixed and cultured to form activated sludge, and the biological coagulation, adsorption and oxidation of activated sludge are used to decompose and remove organic pollutants in sewage. The activated sludge method can remove soluble and colloidal biodegradable organic matter from sewage, as well as suspended solids and other substances that can be adsorbed by activated sludge, and can also remove part of phosphorus and nitrogen.

[0003] At present, the activated sludge method mainly includes AB method, AO method, AAO method, SBR method, etc. The AB method is an adsorption-biodegradation process, in which the A section is mainly based on adsorption, and the B section is mainly based on biodegradation; the AO method is an anaerobic aerobic process, in which the A section is mainly used for nitrogen and phosphorus removal, and the O section is mainly used to remove organic matter in the water; the AAO method is an anaerobic-anoxic-aerobic process, in which the anaerobic section is mainly used to release phosphorus and ammoniate some organic matter, the anoxic section is mainly used for nitrogen removal, and the aerobic section is mainly used for BOD removal, nitrification and phosphorus absorption; the SBR method is an activated sludge sewage treatment technology that operates in an intermittent aeration mode, and its core lies in the SBR reaction tank, which integrates the functions of homogenization, primary sedimentation, biodegradation, and secondary sedimentation, and does not require a sludge return system.

[0004] However, the above-mentioned traditional processes mostly require segmented removal in different tanks and at different stages when removing pollutants from sewage. In addition, the living environment requirements of the microorganisms corresponding to the degradation of COD, ammonia nitrogen and total nitrogen are different, and it is difficult to complete them in the same tank and the same microbial environment, resulting in a waste of treatment tank space and time, and a series of problems such as poor treatment effect, long treatment process, complicated operation and high operating cost.

[0005] In view of this, the present utility model is proposed. Utility Model Content

[0006] The utility model aims to provide a circulating oxygen-controlled enhanced biochemical sewage treatment system, which can remove different pollutants in the same pool and under the same microbial environment.

[0007] The utility model provides a circulating oxygen-controlled enhanced biochemical sewage treatment system, comprising a tank body, in which a mixing area, a screening area, an enhanced biochemical area, a selection area, a circulation area, a mud-water separation area and a reflow area are sequentially connected, a sewage inlet is provided in the mixing area, an aeration device and a dissolved oxygen meter are respectively provided in the screening area, the enhanced biochemical area and the selection area to control the dissolved oxygen concentration, an air lifting device is provided in the circulation area, a packing layer, a water outlet and a mud outlet are provided in the mud-water separation area, the mud outlet is connected with the reflow area, and the reflow area is connected with the mixing area so that at least part of the sludge can flow back to the mixing area.

[0008] Furthermore, the pool body is a rectangular pool body.

[0009] Furthermore, the rectangular pool body is divided into a first partition and a second partition in the width direction, the mixing zone, screening zone, enhanced biochemical zone and selection zone are arranged adjacent to each other in the first partition, and the circulation zone, sedimentation zone and reflux zone are arranged adjacent to each other in the second partition.

[0010] Furthermore, the circulation zone is disposed adjacent to the selection zone, and the recirculation zone is disposed adjacent to the mixing zone.

[0011] Furthermore, adjacent areas in the cell body are arranged with a common wall.

[0012] Furthermore, an overflow weir is provided between the mixing zone and the screening zone.

[0013] Furthermore, a structured composite packing is provided in the screening area.

[0014] Furthermore, an activated sludge inlet and a sludge concentration meter are provided in the enhanced biochemical zone.

[0015] Furthermore, a sludge level meter and a sludge discharge pump are provided in the selection area.

[0016] Furthermore, the mud-water separation area includes a filler sedimentation tank and a clean water area. The filler sedimentation tank is provided with a water distribution area, a filler layer and a sludge area from top to bottom. The water distribution area is connected with the clean water area through the water outlet, and the sludge area is connected with the reflow area through the mud outlet.

[0017] The utility model of the circulating oxygen-controlled enhanced biochemical sewage treatment system divides the main reaction zone into a screening zone, an enhanced biochemical zone and a selection zone. By accurately controlling the dissolved oxygen in each zone, the screening zone is dominated by denitrifying reaction bacteria to form an enhanced denitrification effect, accompanied by nitrification, nitrite reaction and anaerobic ammonia oxidation reaction to form a supplementary denitrification effect, and the enhanced biochemical zone is accompanied by synchronous nitrification and denitrification, full-process autotrophic denitrification, short-range nitrification and denitrification and other biochemical reactions. Various reactions are carried out smoothly and efficiently at the same time, thereby achieving the purpose of removing various pollutants. The selection zone is dominated by denitrifying phosphorus removal bacteria. With multiple processes such as associated biological phosphorus removal, fully autotrophic nitrogen removal and simultaneous nitrification and denitrification, the three areas strengthen the advantages of each area while reacting together. Different reactions in different areas are carried out simultaneously without interfering with each other, thus achieving a more efficient removal effect and realizing the removal of different pollutants in the same pool and under the same microbial environment. The processes of carbon removal and nitrogen removal in sewage treatment are not separated in time and space, which improves the sewage treatment capacity, reduces the treatment time and energy consumption, and makes the operation simpler. It has the advantages of shortening the treatment process, improving the treatment effect and saving the operation cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a structural schematic diagram of the utility model circulating oxygen-controlled enhanced biochemical sewage treatment system.

[0020] Description of reference numerals:

[0021] 1: Mixing zone; 2: Screening zone; 3: Enhanced biochemical zone; 4: Selection zone; 5: Circulation zone; 6: Water distribution zone; 7: Packing layer; 8: Clean water zone; 9: Recirculation zone. DETAILED DESCRIPTION

[0022] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0023] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form also includes the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this description, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0024] The technical solution of the utility model will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0025] Example 1

[0026] Combination Figure 1 As shown, the circulating oxygen-controlled enhanced biochemical sewage treatment system of this embodiment includes a tank body, in which a mixing zone 1, a screening zone 2, an enhanced biochemical zone 3, a selection zone 4, a circulation zone 5, a mud-water separation zone and a reflow zone 9 are sequentially connected. A sewage inlet is provided in the mixing zone 1, and an aeration device and a dissolved oxygen meter are respectively provided in the screening zone 2, the enhanced biochemical zone 3 and the selection zone 4 to control the dissolved oxygen concentration. An air lifting device is provided in the circulation zone 5, and a packing layer 7, a water outlet and a mud outlet are provided in the mud-water separation zone. The mud outlet is connected to the reflow zone 9, and the reflow zone 9 is connected to the mixing zone 1 so that at least part of the sludge can flow back to the mixing zone 1.

[0027] The tank body is a place where sewage is treated in various ways. There is no strict restriction on the arrangement of each zone in the tank body, and it can be reasonably arranged according to actual conditions. In this embodiment, the tank body can adopt a rectangular or quasi-rectangular structure, which is conducive to large-volume hydraulic circulation; the tank body can be divided into a first partition and a second partition in the width direction, wherein the mixing zone 1, the screening zone 2, the enhanced biochemical zone 3 and the selection zone 4 can be arranged adjacent to each other in the first partition in sequence, the circulation zone 5, the sedimentation zone and the recirculation zone 9 can be arranged adjacent to each other in the second partition in sequence, the circulation zone 5 can be arranged adjacent to the selection zone 4, and the recirculation zone 9 can be arranged adjacent to the mixing zone 1, which is conducive to saving reaction time. In addition, adjacent areas in the tank body can be arranged with a common wall, which is conducive to large-volume circulation and saves space, and improves impact resistance.

[0028] The mixing zone 1 is mainly used for mixing raw water with sludge returned from the recirculation zone 9. An overflow weir is provided between the mixing zone 1 and the screening zone 2. The fully mixed sewage enters the screening zone 2 through the overflow weir. A structured combination filler is provided in the screening zone 2. When the characteristic microorganisms in the sewage pass through the structured combination filler, they can adhere to the surface of the structured combination filler and then be intercepted in the screening zone 2.

[0029] An aeration device and a first dissolved oxygen meter are provided in the screening area 2. The screening area 2 is aerated by the aeration device, and the dissolved oxygen concentration in the screening area 2 is monitored by the first dissolved oxygen meter. The aeration device can adopt a pulse oxygen supply mode, or a broadband / disc / tube / liftable hose microporous aerator, whose high oxygenation and dissolved oxygen capacity can provide an appropriate amount of oxygen for the activated sludge in the area, and the dissolved oxygen concentration in the area can be controlled by controlling the installation density of the aeration device in the area. The dissolved oxygen concentration in the screening area 2 is controlled to be 0.1-0.5 mg / L. In the screening area 2, various microorganisms in the activated sludge are screened for the first time, among which the denitrification reaction bacteria are dominant, forming an enhanced denitrification effect; at the same time, nitrification, nitrite reaction and anaerobic ammonia oxidation reaction are accompanied, forming a supplementary denitrification effect.

[0030] An activated sludge inlet and a sludge concentration meter are provided in the enhanced biochemical zone 3. When the system starts to operate, activated sludge is added to the enhanced biochemical zone 3 through the activated sludge inlet, and the concentration of the activated sludge is monitored by the sludge concentration meter. The enhanced biochemical zone 3 is the core area of ​​the entire system and process. An aeration device and a second dissolved oxygen meter are provided in the enhanced biochemical zone 3. The enhanced biochemical zone 3 is aerated by the aeration device, and the dissolved oxygen concentration of the enhanced biochemical zone 3 is monitored by the second dissolved oxygen meter. The aeration device can adopt a broadband microporous aerator. The dissolved oxygen concentration of the enhanced biochemical zone 3 is controlled to be 0.6-1.5 mg / L, which can not only ensure the oxygen demand of the activated sludge to oxidize organic matter, but also meet the environmental conditions of various biochemical reactions such as the accompanying synchronous nitrification and denitrification, the whole autotrophic denitrification, and the short-range nitrification and denitrification. Various reactions are carried out smoothly and efficiently in the enhanced biochemical zone 3 at the same time, so as to achieve the purpose of removing various pollutants.

[0031] After the sewage passes through the enhanced biochemical zone 3, it enters the selection zone 4. The selection zone 4 is provided with an aeration device and a third dissolved oxygen meter. The selection zone 4 is aerated by the aeration device, and the dissolved oxygen concentration of the selection zone 4 is monitored by the third dissolved oxygen meter. The dissolved oxygen concentration of the selection zone 4 is controlled to be 0.15-0.25 mg / L. Various microorganisms in the activated sludge are reselected in the selection zone 4. The phosphorus removal bacteria are dominant in the selection zone 4. The selection zone 4 is provided with a sludge level meter and a sludge discharge pump. The sludge level meter is used to monitor the sludge level in the selection zone 4. The sludge discharge pump is used to discharge the sludge when the sludge level is high. A part of the selected activated sludge is discharged through the sludge discharge pump, and most of the sludge-water mixture enters the circulation zone 5. In the selection zone 4, there are various processes such as biological phosphorus removal, full autotrophic nitrogen removal, and synchronous nitrification and denitrification reactions.

[0032] An air lifting device is provided in the circulation area 5. In the circulation area 5, air lifting is adopted to ensure the internal circulation of the mixed liquid in the entire area and the non-deposition of sludge. The sewage passing through the circulation area 5 then enters the mud-water separation area, which includes a filler sedimentation tank and a clean water area 8. The filler sedimentation tank is provided with a water distribution area 6, a filler layer 7 and a sludge area (not shown) from top to bottom. The water distribution area 6 is connected to the clean water area 8 through the water outlet, and the sludge area is connected to the return area 9 through the mud outlet. Part of the sludge in the return area 9 flows back to the mixing area 1 and mixes with the raw water, thereby completing the overall circulation of the system.

[0033] The use of the above-mentioned circulating oxygen-controlled enhanced biochemical sewage treatment system to treat sewage may include the following steps: S1: sending sewage into the mixing zone 1, sending activated sludge into the enhanced biochemical zone 3, and mixing the sewage with the sludge from the reflow zone 9 in the mixing zone 1; S2: the mixed sewage enters the screening zone 2, the enhanced biochemical zone 3 and the selection zone 4 in turn for treatment, and during the treatment process, the dissolved oxygen concentrations of the screening zone 2, the enhanced biochemical zone 3 and the selection zone 4 are respectively controlled by an aeration device and a dissolved oxygen meter; S3: the treated sewage circulates in the circulation zone 5 and then enters the mud-water separation zone for mud-water separation, and the clean water formed by the mud-water separation is discharged from the circulating oxygen-controlled enhanced biochemical sewage treatment system, and the sludge formed by the mud-water separation enters the reflow zone 9, and at least part of the sludge in the reflow zone 9 is returned to the mixing zone 1.

[0034] During the treatment process, except for controlling the dissolved oxygen concentration in the screening zone 2 to 0.1-0.5 mg / L, the dissolved oxygen concentration in the enhanced biochemical zone 3 to 0.6-1.5 mg / L, and the dissolved oxygen concentration in the selection zone 4 to 0.15-0.25 mg / L, there are no strict restrictions on other process parameters, and other process parameters of the entire process can be adjusted according to the raw water quality.

[0035] When the above-mentioned circulating oxygen-controlled enhanced biochemical sewage treatment system is used to treat urban sewage, the water quality of urban sewage is: COD cr 500mg / L, BOD5 300mg / L, SS250mg / L, NH3-N 30mg / L, TN 40mg / L, TP 5mg / L; the core process parameters in the treatment process are controlled as follows: the dissolved oxygen concentration in the screening area 2 is 0.3mg / L, the dissolved oxygen concentration in the enhanced biochemical area 3 is 0.9mg / L, and the dissolved oxygen concentration in the control selection area 4 is 0.2mg / L; the water quality of the treated clean water is COD cr 50mg / L, BOD5 10mg / L, SS20mg / L, NH3-N 5mg / L, TN 15mg / L, TP 2mg / L.

[0036] When the above-mentioned circulating oxygen-controlled enhanced biochemical sewage treatment system is used to treat heavy sewage, the water quality of the heavy sewage is: CODcr 8000mg / L, BOD5 5000mg / L, SS2000mg / L, NH3-N 1000mg / L, TN 1200mg / L; the core process parameters during the treatment process are controlled as follows: the dissolved oxygen concentration in the screening area 2 is 0.1mg / L, the dissolved oxygen concentration in the enhanced biochemical area 3 is 1.0mg / L, and the dissolved oxygen concentration in the control selection area 4 is 0.25mg / L; the quality of the treated clean water is COD cr 300mg / L, BOD5 20mg / L, SS 70mg / L, NH3-N 40mg / L, TN 70mg / L

[0037] The circulating oxygen-controlled enhanced biochemical sewage treatment system of this embodiment divides the main reaction area into a screening area 2, an enhanced biochemical area 3 and a selection area 4. By accurately controlling the dissolved oxygen in each area, the screening area 2 is dominated by denitrifying reaction bacteria to form an enhanced denitrification effect, accompanied by nitrification, nitrite reaction and anaerobic ammonia oxidation reaction to form a supplementary denitrification effect, and the enhanced biochemical area 3 is accompanied by synchronous nitrification and denitrification, full-process autotrophic denitrification, short-range nitrification and denitrification and other biochemical reactions. Various reactions are carried out smoothly and efficiently at the same time, thereby achieving the purpose of removing various pollutants. The selection area 4 is dominated by denitrifying phosphorus removal bacteria. The three zones strengthen the advantages of each zone while reacting together, and different reactions in different zones are carried out simultaneously without interfering with each other, thus achieving a more efficient removal effect and realizing the removal of different pollutants in the same pool and under the same microbial environment, so that the processes of carbon removal and nitrogen removal in sewage treatment are not separated in time and space, which improves the sewage treatment capacity, reduces the treatment time and energy consumption, and makes the operation simpler, with the advantages of shortening the treatment process, improving the treatment effect, and saving the operation cost.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. A circulating oxygen-controlled enhanced biochemical sewage treatment system, characterized in that: The invention comprises a tank body, in which a mixing zone, a screening zone, an enhanced biochemical zone, a selection zone, a circulation zone, a mud-water separation zone and a reflow zone are sequentially connected. A sewage inlet is arranged in the mixing zone. Aeration devices and dissolved oxygen meters are respectively arranged in the screening zone, the enhanced biochemical zone and the selection zone to control the dissolved oxygen concentration. An air lifting device is arranged in the circulation zone. A packing layer, a water outlet and a mud outlet are arranged in the mud-water separation zone. The mud outlet is connected with the reflow zone, and the reflow zone is connected with the mixing zone so that at least part of the sludge can flow back to the mixing zone.

2. The circulating oxygen-controlled enhanced biochemical sewage treatment system according to claim 1 is characterized in that: The pool body is a rectangular pool body.

3. The circulating oxygen-controlled enhanced biochemical sewage treatment system according to claim 2 is characterized in that: The rectangular pool body is divided into a first partition and a second partition in the width direction. The mixing zone, screening zone, enhanced biochemical zone and selection zone are arranged adjacent to each other in the first partition, and the circulation zone, sedimentation zone and reflux zone are arranged adjacent to each other in the second partition.

4. The circulating oxygen-controlled enhanced biochemical sewage treatment system according to claim 3 is characterized in that: The circulation zone is adjacent to the selection zone, and the reflux zone is adjacent to the mixing zone.

5. The circulating oxygen-controlled enhanced biochemical sewage treatment system according to claim 3 is characterized in that: Adjacent areas in the pool body are arranged with a common wall.

6. The circulating oxygen-controlled enhanced biochemical sewage treatment system according to claim 1 is characterized in that: An overflow weir is provided between the mixing zone and the screening zone.

7. The circulating oxygen-controlled enhanced biochemical sewage treatment system according to claim 1 is characterized in that: A structured composite packing is arranged in the screening area.

8. The circulating oxygen-controlled enhanced biochemical sewage treatment system according to claim 1 is characterized in that: An activated sludge inlet and a sludge concentration meter are provided in the enhanced biochemical area.

9. The circulating oxygen-controlled enhanced biochemical sewage treatment system according to claim 1, characterized in that: Sludge level meter and sludge pump are installed in the selection area.

10. The circulating oxygen-controlled enhanced biochemical sewage treatment system according to claim 1, characterized in that: The mud-water separation area includes a filler sedimentation tank and a clean water area. The filler sedimentation tank is provided with a water distribution area, a filler layer and a sludge area from top to bottom. The water distribution area is connected with the clean water area through the water outlet, and the sludge area is connected with the reflow area through the mud outlet.

Images