CN115608009A - Assembled secondary sedimentation tank and sewage treatment equipment - Google Patents
Assembled secondary sedimentation tank and sewage treatment equipment Download PDFInfo
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- CN115608009A CN115608009A CN202211393300.1A CN202211393300A CN115608009A CN 115608009 A CN115608009 A CN 115608009A CN 202211393300 A CN202211393300 A CN 202211393300A CN 115608009 A CN115608009 A CN 115608009A
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- pipe
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D21/00—Separation of suspended solid particles from liquids by sedimentation
- B01D21/02—Settling tanks with single outlets for the separated liquid
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D21/00—Separation of suspended solid particles from liquids by sedimentation
- B01D21/24—Feed or discharge mechanisms for settling tanks
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D21/00—Separation of suspended solid particles from liquids by sedimentation
- B01D21/24—Feed or discharge mechanisms for settling tanks
- B01D21/2405—Feed mechanisms for settling tanks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D21/00—Separation of suspended solid particles from liquids by sedimentation
- B01D21/24—Feed or discharge mechanisms for settling tanks
- B01D21/2444—Discharge mechanisms for the classified liquid
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/02—Aerobic processes
- C02F3/12—Activated sludge processes
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/10—Biological treatment of water, waste water, or sewage
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- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Biodiversity & Conservation Biology (AREA)
- Microbiology (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Activated Sludge Processes (AREA)
Abstract
The invention discloses an assembled secondary sedimentation tank and sewage treatment equipment, wherein the assembled secondary sedimentation tank comprises a tank body and also comprises: an aeration system, a water distribution system, a solid-liquid-gas separation system and a water outlet system which are arranged in the secondary sedimentation tank body from bottom to top; the aeration system, the water distribution system, the solid-liquid-gas separation system and the water outlet system are detachably connected with the pool body; the aeration system comprises an aeration pipe and an aerator arranged on the aeration pipe; the water distribution system comprises a main water distribution pipe and branch water distribution pipes, one end of the main water distribution pipe extends to the outer side of the tank body to form a water inlet end, the other end of the main water distribution pipe is a blind end, and the branch water distribution pipes are arranged on two sides of the main water distribution pipe at intervals; the solid-liquid-gas separation system comprises a solid-liquid-gas separator and a gas collection chamber arranged on the solid-liquid-gas separator, and the problem of anaerobic sludge turning in the prior art is solved.
Description
Technical Field
The invention relates to the field of sewage treatment, in particular to an assembled secondary sedimentation tank and sewage treatment equipment.
Background
The secondary sedimentation tank is an important component of an activated sludge system, is used for clarifying mixed liquor and recovering and concentrating activated sludge, and has good and bad effect, and the quality of effluent and the concentration of return sludge are directly influenced. Because the precipitation and concentration effects are poor, the activity of the effluent can be increased to obtain mud suspended matters, so that the BOD mass concentration of the effluent is increased; meanwhile, the concentration of the returned sludge is reduced, so that the concentration of mixed liquid in the aeration tank is reduced, and the purification effect is influenced.
The secondary sedimentation tank of a general sewage treatment plant mostly adopts a traditional advection type sedimentation tank or a radial type sedimentation tank, the main design parameter is surface load, and the range of the surface load is 1.0-2.0 (m) 3 /m 2 H) and a mud scraper is required. Chinese patent CN202110765083.3 discloses a rectangular sloping plate secondary sedimentation tank, which comprises a sedimentation tank body, a water inlet part, a sloping plate part, a water outlet part, a mud discharging part and a chain plate type mud scraping and skimming part, wherein the water inlet part comprises a water inlet channel, the water inlet channel is arranged along the edge of the sedimentation tank body, and the bottom of the water inlet channel is uniformly provided with water distribution holes; the inclined plate part is arranged on the upper part of the sedimentation tank body, the inclined plate part is provided with a perforated aeration pipe, and anaerobic sludge turning is easy to occur in daily operation, so that SS and TP standard exceeding of system effluent is caused.
Disclosure of Invention
The invention provides an assembled secondary sedimentation tank and sewage treatment equipment, which solve the problem of anaerobic sludge turning in the prior art, can improve the surface load of the equipment, enhance the treatment capacity and reduce the land cost of the equipment when in application; the assembled type can be used for civil construction and can also be used for steel structure construction.
In order to solve the technical problem, the invention provides the following technical scheme:
the utility model provides an assembled two heavy ponds, includes the cell body, still includes:
an aeration system, a water distribution system, a solid-liquid-gas separation system and a water outlet system which are arranged in the secondary sedimentation tank body from bottom to top; the aeration system, the water distribution system, the solid-liquid-gas separation system and the water outlet system are detachably connected with the pool body;
the aeration system comprises an aeration pipe and an aerator arranged on the aeration pipe;
the aerator can adopt an aeration disc, a tubular aerator or a perforated pipe aerator.
The water distribution system comprises a main water distribution pipe and branch water distribution pipes, one end of the main water distribution pipe extends to the outer side of the pool body to form a water inlet end, the other end of the main water distribution pipe is a blind end, and the branch water distribution pipes are arranged on two sides of the main water distribution pipe at intervals;
the solid-liquid-gas separation system comprises a solid-liquid-gas separator and a gas collection chamber arranged on the solid-liquid-gas separator.
The assembled secondary sedimentation tank, the aeration system, the water distribution system, the solid-liquid-gas separation system and the water outlet system are detachably connected with the tank body, so that the assembly is convenient; meanwhile, the tank body can be assembled into secondary sedimentation tanks with different sizes according to different sewage treatment requirements; the tank body can be used for a steel structure tank body, but is not limited to a steel structure.
The components used by each system can be produced independently, so that the industrialization is facilitated;
the assembled mode, the efficiency of construction is higher.
Compared with the traditional sewage treatment tank with left inlet and right outlet and two-phase separation modes, the scheme has the advantages that solid-liquid-gas three-phase separation is realized, and the separation efficiency is higher; meanwhile, the effect of gas recycling can be realized;
preferably, the inlet end of the aeration pipe is connected with a fan, and the outlet end of the aeration pipe is connected with an emptying pipe.
This scheme is through setting up the aeration pipe, and the sediment of mud is efficient.
Preferably, the device also comprises a sludge pipe for conveying the sludge, wherein the sludge pipe is provided with an air stripping pipe for air stripping the sludge, and the air stripping pipe is communicated with the air collection chamber.
Preferably, the water outlet system comprises a water outlet groove and water outlet weirs connected with two sides of the water outlet groove, the water outlet groove is arranged in a gradient manner, and the gradient bottom of the water outlet groove is connected with a water collecting groove.
Preferably, one end of the water collecting tank is provided with a water collecting opening, and the water collecting opening is connected with a water outlet pipe.
Preferably, the gradient of the water outlet groove is 0.2-0.5%.
This scheme still provides a sewage treatment device, including foretell assembled two heavy ponds, still includes mud promotion concentration tank.
Preferably, a sludge return pump for sludge return is arranged in the sludge lifting concentration tank, and the sludge return pump is connected with a sludge discharge pipe.
When the assembled sewage treatment equipment works, water is fed and is connected with water outlets of all relevant processes of an activated sludge process, including water outlets of an AAO biochemical pool, an AOA (anaerobic-anoxic-oxic) pool, a CASS (Cyclic activated sludge System) and an oxidation ditch, the water inlet pipe is connected into the equipment, and a main water distribution pipe and a branch water distribution pipe are arranged in the equipment; in order to balance the treated water quantity of each area, the design of the water distribution branch pipes needs to design and account according to the inflow and the set flow rate.
The aeration system of the biochemical tank is connected into the system through an aeration pipe, and the aeration is carried out by uniformly arranging aerators, and the aeration air quantity is comprehensively determined by the water inlet quantity, the area of the bottom of the tank and the air stirring strength. The aeration system has the effects of uniformly aerating the water entering the equipment, further degrading pollutants in the system under the action of aeration, and enabling the states of all points in the secondary sedimentation tank equipment to be uniform under the action of aeration stirring, so that the problem that the secondary sedimentation tank turns over mud caused by local anaerobism in the operation of the traditional secondary sedimentation tank is solved.
Under the action of the water distribution system and the aeration system, sewage is in an upflow state in the equipment, and in a laminar flow area, a hydraulic flow state is in a laminar flow state.
When the solid-liquid-gas mixture rises to the solid-liquid-gas separation system, the state of solid-liquid-gas separation can occur, and the gas with the lightest weight can be guided by the solid-liquid-gas separator and gathered in a gas collection chamber of the solid-liquid-gas separator to be used as the power for the gas stripping of the sludge in the following sludge hopper. The sludge with the heaviest mass interacts with each other in the ascending process under the action of bubble stirring to generate natural flocculation, and the sludge mass can flow back to the bottom of the system under the interception action of the inclined plate in the solid-liquid gas separator, and can gradually migrate to the sludge hopper without the aeration device and be lifted into the sludge lifting concentration tank by the air lifting device in the equipment for the sludge backflow in the system. The separated water is further clarified by a clarification area and is separated from a small amount of discrete sludge, clear water is collected in a water outlet weir of the water outlet system, and the small amount of discrete sludge flows back to the solid-liquid separator under the action of gravity.
Compared with the prior art, the invention has the following advantages:
the aeration system, the water distribution system, the solid-liquid-gas separation system and the water outlet system are detachably connected with the pool body, so that the assembly is convenient; the design of the water distribution branch pipes needs to design and account according to the inflow and the set flow rate.
The aeration system carries out even aeration to equipment intake, through the aeration effect, can further degrade the pollutant in the system, in addition, through aeration stirring effect, can make the inside each point state of two heavy pond equipment even, solve the two heavy pond that appear in the operation of traditional two heavy pond because of the local anaerobism two heavy pond turn over the mud condition that causes.
Drawings
The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:
FIG. 1 is a schematic view of the top surface of the sewage treatment apparatus of the present invention.
FIG. 2 isbase:Sub>A sectional view of the sewage treatment apparatus of the section A-A in FIG. 1 according to the present invention.
FIG. 3 is a plan view of the interface sewage treatment equipment of the water distribution system of the present invention.
FIG. 4 is a plan view of a sewage treatment apparatus of an aeration tube interface according to the present invention.
FIG. 5 is a plan view of the sewage treatment apparatus of the solid-liquid separator interface of the present invention.
Reference numbers and corresponding part names in the drawings: 1. an aeration system; 11. an aeration pipe; 12. an aerator; 13. an inlet end; 14. an outlet end; 2. a water distribution system; 21. a water distribution main pipe; 22. a water distribution branch pipe; 3. a solid-liquid-gas separation system; 31. a solid-liquid separator; 32. a gas collecting chamber; 4. a water outlet system; 41. a water outlet groove; 42. an effluent weir; 43. a water collection tank; 44. a water collection port; 45. a water outlet pipe; 5. a tank body; 6. a sludge lifting and concentrating tank; 7. a sludge pipe; 8. a gas stripping tube; 9. a sludge reflux pump; 10. a sludge discharge pipe.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not used as limitations of the present invention.
Examples
As shown in fig. 1 to 5, an assembled secondary sedimentation tank includes a tank body 5, and further includes: an aeration system 1, a water distribution system 2, a solid-liquid-gas separation system 3 and a water outlet system 4 which are arranged in a secondary sedimentation tank body 5 from bottom to top; the aeration system 1, the water distribution system 2, the solid-liquid-gas separation system 3 and the water outlet system 4 are detachably connected with the tank body 5;
the aeration system 1 comprises an aeration pipe 11 and an aerator 12 arranged on the aeration pipe 11;
the aerator 12 may be an aeration tray, a tube aerator, or a perforated tube aerator.
The water distribution system 2 comprises a main water distribution pipe 21 and branch water distribution pipes 22, one end of the main water distribution pipe 21 extends to the outer side of the tank body 5 to form a water inlet end, the other end of the main water distribution pipe 21 is a blind end, and the branch water distribution pipes 22 are arranged at two sides of the main water distribution pipe 21 at intervals;
the solid-liquid-gas separation system 3 comprises a solid-liquid separator 31 and a gas collection chamber 32 arranged on the solid-liquid separator 31.
Preferably, the inlet end 13 of the aeration pipe 11 is connected with a fan, and the outlet end 14 of the aeration pipe 11 is connected with an emptying pipe.
Preferably, the device also comprises a sludge pipe 7 for conveying sludge, wherein an air stripping pipe 8 for air stripping sludge is arranged on the sludge pipe 7, and the air stripping pipe 8 is communicated with the air collecting chamber 32.
Preferably, the effluent system 4 comprises an effluent trough 41 and effluent weirs 42 connected to both sides of the effluent trough 41, wherein the effluent trough 41 is disposed in a slope, and the bottom of the slope of the effluent trough 41 is connected to a water collecting tank 43.
Preferably, one end of the water collecting tank 43 is provided with a water collecting port 44, and the water collecting port 44 is connected with a water outlet pipe 45.
Preferably, the gradient of the water outlet groove 41 is 0.2% -0.5%.
This scheme still provides a sewage treatment device, including foretell assembled two heavy ponds, still includes mud promotion concentration tank 6.
Preferably, a sludge return pump 9 for sludge return is arranged in the sludge lifting concentration tank 6, and a sludge discharge pipe 10 is connected to the sludge return pump 9.
When the assembled sewage treatment equipment works, water is fed into the equipment and is connected with water outlets of all processes related to an activated sludge process, including water outlets of an AAO biochemical pool, an AOA (anaerobic-anoxic-oxic) pool, a CASS (Cyclic activated sludge System) pool and an oxidation ditch, and a main water distribution pipe 21 and a branch water distribution pipe 22 are arranged in the equipment; in order to balance the treated water amount in each area, the design of the branch water distribution pipes 22 needs to design accounting according to the inflow and the set flow rate.
The aeration system 1 of the biochemical pool is connected into the system through an aeration pipe 11, and gas stirring is carried out through uniformly arranging aerators 12, and aeration gas flow is comprehensively determined by water inlet amount, pool bottom area and gas stirring strength. The aeration system 1 has the main function of uniformly aerating the water entering the equipment, pollutants in the system can be further degraded through the aeration effect, in addition, the states of all points in the secondary sedimentation tank equipment can be uniform through the aeration stirring effect, and the problem that the secondary sedimentation tank turns over mud caused by local anaerobic during the operation of the traditional secondary sedimentation tank is solved. The interaction of the sludge in the secondary sedimentation tank is promoted by gas stirring, so that the effect of biological flocculation is generated, and the sedimentation efficiency of equipment is improved.
Under the action of the water distribution system and the aeration system 1, the sewage is in an upflow state in the equipment, and in a laminar flow area, the hydraulic flow state is in a laminar flow state.
When the solid-liquid-gas mixture rises to the solid-liquid-gas separation system 3, the state of solid-liquid-gas separation can occur, and the gas with the lightest weight can be stripped by the solid-liquid-gas separator 31 and gathered in the gas collection chamber 32 of the solid-liquid-gas separator 31 to be used as the power for the gas stripping of the sludge in the following sludge hopper. The sludge with the heaviest mass is intercepted by the inclined plate in the solid-liquid separator, sludge clusters can be flocculated to the bottom of the system due to the sludge clusters, and can be gradually transferred to a sludge hopper without an aeration device and lifted into a sludge lifting concentration tank 6 by the air lifting device in the equipment for the sludge reflux in the system. The separated water is further clarified by the clarification zone and separated from a small amount of discrete sludge, clear water is collected in the effluent weir 42 of the effluent system 4, and the small amount of discrete sludge flows back to the solid-liquid separator 31 under the action of gravity.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are merely exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (8)
1. The utility model provides an assembled two heavy ponds, includes cell body (5), its characterized in that still includes:
an aeration system (1), a water distribution system (2), a solid-liquid-gas separation system (3) and a water outlet system (4) which are arranged in a secondary sedimentation tank body (5) from bottom to top; the aeration system (1), the water distribution system (2), the solid-liquid-gas separation system (3) and the water outlet system (4) are detachably connected with the pool body (5);
the aeration system (1) comprises an aeration pipe (11) and an aerator (12) arranged on the aeration pipe (11);
the water distribution system (2) comprises a main water distribution pipe (21) and branch water distribution pipes (22), one end of the main water distribution pipe (21) extends to the outer side of the tank body (5) to form a water inlet end, the other end of the main water distribution pipe (21) is a blind end, and the branch water distribution pipes (22) are arranged on two sides of the main water distribution pipe (21) at intervals;
the solid-liquid-gas separation system (3) comprises a solid-liquid separator (31) and a gas collection chamber (32) arranged on the solid-liquid separator (31).
2. The fabricated secondary sedimentation tank of claim 1, wherein an inlet end (13) of the aeration pipe (11) is connected with a blower, and an outlet end (14) of the aeration pipe (11) is connected with a drain pipe.
3. The assembly type secondary sedimentation tank as claimed in claim 1, further comprising a sludge pipe (7) for conveying sludge, wherein an air stripping pipe (8) for air stripping sludge is arranged on the sludge pipe (7), and the air stripping pipe (8) is communicated with the air collection chamber (32).
4. The assembly type secondary sedimentation tank as claimed in claim 1, wherein the effluent system (4) comprises an effluent tank (41) and effluent weirs (42) connected with both sides of the effluent tank (41), the effluent tank (41) is arranged in a slope, and the slope bottom of the effluent tank (41) is connected with a water collecting tank (43).
5. The assembled secondary sedimentation tank according to claim 4, wherein a water collection port (44) is provided at one end of the water collection tank (43), and a water outlet pipe (45) is connected to the water collection port.
6. The fabricated secondary sedimentation tank of claim 5, wherein the outlet channel has a slope of 0.2% to 0.5%.
7. An apparatus for treating sewage, comprising the fabricated secondary sedimentation tank of any one of claims 1 to 6, and further comprising a sludge elevation thickening tank (6).
8. The sewage treatment device according to claim 7, wherein a sludge return pump (9) for returning sludge is arranged in the sludge lifting concentration tank (6), and a sludge discharge pipe (10) is connected to the sludge return pump (9).
Priority Applications (1)
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CN202211393300.1A CN115608009A (en) | 2022-11-08 | 2022-11-08 | Assembled secondary sedimentation tank and sewage treatment equipment |
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CN202211393300.1A CN115608009A (en) | 2022-11-08 | 2022-11-08 | Assembled secondary sedimentation tank and sewage treatment equipment |
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CN202211393300.1A Pending CN115608009A (en) | 2022-11-08 | 2022-11-08 | Assembled secondary sedimentation tank and sewage treatment equipment |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116637409A (en) * | 2023-06-13 | 2023-08-25 | 云南合续环境科技股份有限公司 | Assembled sewage sedimentation tank |
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2022
- 2022-11-08 CN CN202211393300.1A patent/CN115608009A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN116637409A (en) * | 2023-06-13 | 2023-08-25 | 云南合续环境科技股份有限公司 | Assembled sewage sedimentation tank |
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