CN203890088U - Efficient dissolved air flotation system - Google Patents
Efficient dissolved air flotation system Download PDFInfo
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- CN203890088U CN203890088U CN201420241163.4U CN201420241163U CN203890088U CN 203890088 U CN203890088 U CN 203890088U CN 201420241163 U CN201420241163 U CN 201420241163U CN 203890088 U CN203890088 U CN 203890088U
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Abstract
The utility model relates to an efficient dissolved air flotation system. The system comprises an air flotation tank, a slag scraping machine, a slag discharge device and an effluent device mounted in the air flotation tank, and an air-liquid mixing pump water inlet pipe led from the tail end of the air flotation tank, wherein an air inlet pipe is arranged on the air-liquid mixing pump water inlet pipe and connected with an air-liquid mixing pump and a micro-bubble generator and a high-pressure saturated dissolved air water pipe led from the micro bubble generator and an externally connected sewage pipe are communicated with a dissolved air releaser located at the tail end of the air flotation tank water inlet pipe by virtue of a T-type mixer. Compared with the prior art, the efficient dissolved air flotation system disclosed by the utility model has the beneficial effects that the dissolved gas water generated by the system has good stability and large bubble density; 2) the micro-bubble of which the size is about 5mu m produced by the system easily adheres suspended substances and oil particles in the sewage; 3) since the dissolved gas ratio of dissolved gas water in the system can reach 30-35%, and better removal effect can be achieved; 4) the system is simple, easily debugged and stable in operation; 5) the operation is stable and reliable and the advantages of energy conservation, consumption reduction and high degree of automation are achieved.
Description
Technical field
The utility model relates to the air-flotation system in water technology, is mainly used in the purifying treatment of Steel Mill, steelworks, coke-oven plant, oil refining and oil recovery factory, paper mill, food and chemical plant wastewater, relates in particular to a kind of air-dissolving air-float system.
Background technology
At present, in the air-float technology of trade effluent and municipal sewage treatment, according to the method difference that produces bubble, air supporting can be divided into the floating upper method of electrolysis, turbine air flotation method and the floating upper method of dissolved air.
The floating upper method of electrolysis is to utilize insoluble anode and negative electrode, passes into the direct current of 5-10V, directly by wastewater electrolytic.Anode and negative electrode produce respectively hydrogen and oxygen; form a large amount of micro-bubbles, the suspended particle in waste water or the first flocs unit forming through coagulating treatment are adhered to and float up to the water surface, produce foam layer; then with slag scraper, foam is struck off, thereby reach the object of solid-liquid separation.The method is mainly used in the Industrial Wastewater Treatment of middle and small scale, and its shortcoming is: current consumption is large, and cost of investment is high; Operation operational management is more complicated, inconvenient operation; The easy fouling of electrode, work-ing life is short, thereby seldom uses in industry.
Turbine air flotation method refers to air is incorporated near the mixing tank or turbine of a high speed rotating, by the high speed shear power of high speed rotating mixing tank or turbine, the air of introducing is cut into a lot of tiny bubbles, thereby realize pneumatically supported process.Its shortcoming is large (d>1mm) of bubble scale forming, and bobble rise velocity is fast, and specific surface area is little, and shorter with the duration of contact of suspended substance, air flotation effect is bad.
The floating upper method of dissolved air can be divided into two kinds of the floating upper method of molten gas vacuum and the floating upper methods of pressure air-dissolving according to the method difference that produces bubble:
The floating upper method of molten gas vacuum refer to material under normal pressure by aeration, make its abundant molten gas, then under the condition of vacuum, pressure reduces suddenly, thereby the molten air elutriation in material is gone out, form a large amount of trickle bubbles, bubble adhesion, on granule foreign, bubbles through the water column it, thereby forms scum, be removed with slag scraper again, finally reach the object of solid-liquid separation.Its shortcoming is: under normal pressure, air dissolves degree is low, the limited amount of bubble; Need Sealing Arrangement to maintain vacuum, running maintenance is more difficult.All devices, in the air flotation pool of sealing, makes air flotation pool complex structure, operational management, maintenance inconvenience.
The floating upper method of pressure air-dissolving refer to material under the condition of pressurization by aeration, make its abundant molten gas.Then under the condition of normal pressure, pressure reduces suddenly, thereby the molten air elutriation in material is gone out, form a large amount of trickle bubbles, bubble adhesion, on granule foreign, bubbles through the water column it, thereby formation scum, then be removed with slag scraper, finally reach the object of solid-liquid separation.Need the equipment such as dissolving, air compressor machine or ejector, water pump, floor space is large, and cost of investment is high.
Also has in addition a kind of air flotation turbo, its action principle is to flow into through pretreated sewage the small inflatable section that Cavltation aerator is housed, sewage fully mixes with the microbubble that aerator produces by inflation section in the process rising, and aerator is transferred to the air on the water surface under water by air draft pipe.The principle of work of aerator is to utilize the high speed rotating of the loose gas impeller in air delivery pipe bottom in water, to form a vacuum zone, air on liquid level is inputted in water by aerator, fill a vacuum, microbubble produces also thereupon and rises to the water surface to spiral type, and airborne oxygen also dissolves in water thereupon.Due to the imbalance of density between air-water mixture and liquid, produce a buoyancy vertically upward, take SS (suspended solid) to the water surface.In floating-upward process, it is upper that microbubble can be attached to SS, and after the arrival water surface, SS just relies on these bubbles to support and maintain the water surface.The SS floating on the surface is removed by chain mud scraper discontinuously.Its shortcoming is that stopping up often appears in the aeration head of aerator, and debugging difficulty is large, and Bubble formation effect is unstable, and the case of domestic successful operation is less.
Summary of the invention
The utility model provides a kind of high-efficiency dissolved air flotation system, utilizes high pressure solution gas principle to produce highdensity microbubble, and its specific surface area is large, catches effect strong, can efficiently remove oil slick in sewage, oil in water emulsion, suspended solid SS and chemical oxygen demand COD.
In order to achieve the above object, the utility model is realized by the following technical solutions:
A kind of high-efficiency dissolved air flotation system, comprise air flotation pool, be arranged on slag scraper, slag discharging device and discharging device in air flotation pool, the gas-liquid mixing pump water inlet pipe of drawing from air flotation pool end, which is provided with inlet pipe, and connecting gas-liquid mixing pump, microbubble generator by gas-liquid mixed pipe, the high pressure saturated dissolved gas water pipe of drawing from microbubble generator is communicated with the dissolved air release of air flotation pool water inlet pipe end by T-shaped mixing tank with external sewage water inlet pipe.
Described air flotation pool is sloping plate deposition-air flotation pool, is provided with shore pipe at the bottom of pond.
Described slag scraper is chain-plate type slag scraper, and slag discharging device is made up of ash pit and scum pipe, and discharging device is made up of effluent trough and rising pipe.
Described gas-liquid mixing pump is mono-pump.
Described microbubble generator by housing, be placed in the cluster type microbubble pipe in housing, import, outlet, vent valve and the pressure unit being located on housing forms, described import, outlet in be provided with web plate.
Described gas-liquid mixing pump water inlet pipe is provided with line strainer; Before inlet pipe, establish gas meter, on the pipeline after inlet pipe, establish vacuum meter; High pressure saturated dissolved gas water pipe is provided with magnetic flow meter and reducing valve.
The other operation housing of establishing of described microbubble generator, realizes the chain control of the each device of system and valve by PLC.
Compared with prior art, the beneficial effects of the utility model are:
1) system adopts mono-pump to replace traditional reflux pump, dissolving, air compressor machine etc., reduces floor space, reduces running cost, reduces and safeguards manpower; Meanwhile, dissolved-air pressure is promoted to 1.0-1.2Mpa, doubles than traditional air-dissolving air-float, dissolved air water good stability, bubble density that therefore system produces are large.
2) domestic pneumatically supported bubble diameter is generally at >=20 μ m, and utilizes microbubble generator, and system produces the micro-bubble that particle diameter is about 5 μ m left and right, more easily adheres to suspended substance and elaioleucite in sewage; Cancel traditional micropore reliever simultaneously, the phenomenon of blockage of the micro orifice can not occur.
3) the molten gas of system is than high; Microbubble generation systems is that the air of elevated pressures (1.0-1.2Mpa) is mixed with water, then produces dissolved air water by the cyclogenesis of microbubble generator, and the molten gas ratio of this dissolved air water can reach 30-35%, thereby has reached better removal effect.
4) system architecture is simple, is easy to debugging, stable; For the larger water inlet system of flow rate fluctuation, can carry out the closed-loop control of flow, to ensure the stable of effluent quality.
5) energy-saving and cost-reducing, level of automation is high; Utilize variable-frequency control technique control spiral pump rotating speed not higher than 300rpm, stable when work, quiet, greatly extend work-ing life of equipment, save energy consumption more than 20% simultaneously; There is PLC intelligent control program, system run all right, reliable, and can realize and Central Control Room networking, facilitate remote monitoring, on-the-spot without personal management.
Brief description of the drawings
Fig. 1 is structural representation of the present utility model.
Fig. 2 is the structural representation of microbubble generator.
Fig. 3 is technological process schematic diagram of the present utility model.
Fig. 4 is the structural representation of T-shaped mixing tank.
In figure: 1. sewage water inlet pipe 2.T type mixing tank 3. air flotation pool water inlet pipe 4. dissolved air release 5. shore pipe 6. slag scraper 7. air flotation pool 8. scum pipe 9. ash pit 10. effluent trough 11. rising pipe 12. gas-liquid mixing pump water inlet pipe 13. line strainer 14. inlet pipe 15. gas meter 16. vacuum meters 17. operate the housing 18. gas-liquid mixed pipe 19. microbubble generator 20. gas-liquid mixing pump 21. magnetic flow meter 22. reducing valve 23. former pond of high pressure saturated dissolved gas water pipe 24. 25. lift pump 26. swash plate 191. housing 192. vent valve 193. pressure units 194. and export web plate 195. and export 196. microbubble pipe 197. import web plate 198. import 201. dissolved air water diffuser tube 202. cyclone flow deflectors
Embodiment
Below in conjunction with accompanying drawing, embodiment of the present utility model is described further:
See Fig. 1, it is structural representation of the present utility model, a kind of high-efficiency dissolved air flotation system of the utility model, comprise air flotation pool 7, be arranged on slag scraper 6, slag discharging device and discharging device in air flotation pool 7, the gas-liquid mixing pump water inlet pipe 12 of drawing from air flotation pool 7 ends, which is provided with inlet pipe 14, and connecting gas-liquid mixing pump 20, microbubble generator 19 by gas-liquid mixed pipe 18, the high pressure saturated dissolved gas water pipe 23 of drawing from microbubble generator 19 is communicated with the dissolved air release 4 of air flotation pool water inlet pipe 3 ends by T-shaped mixing tank 2 with external sewage water inlet pipe 1.
Described air flotation pool 7 is sloping plate deposition-air flotation pool, is provided with shore pipe 5 at the bottom of pond.
Described slag scraper 6 is chain-plate type slag scraper, and slag discharging device is made up of ash pit 9 and scum pipe 8, and discharging device is made up of effluent trough 10 and rising pipe 11.
Described gas-liquid mixing pump 20 is mono-pump.
See Fig. 2, it is the structural representation of microbubble generator, described microbubble generator 19 by housing 191, be placed in cluster type microbubble pipe 196 in housing 191, the import 198, outlet 195, vent valve 192 and the pressure unit 193 that are located on housing 191 form, and in described import 198, outlet 195, is provided with web plate 194,197.
Described gas-liquid mixing pump water inlet pipe 12 is provided with line strainer 13; Before inlet pipe 14, establish gas meter 15, on the pipeline after inlet pipe 14, establish vacuum meter 16; High pressure saturated dissolved gas water pipe 23 is provided with magnetic flow meter 21 and reducing valve 22.
The other operation housing 17 of establishing of described microbubble generator 19, realizes the chain control of the each device of system and valve by PLC.
The principle of work of a kind of high-efficiency dissolved air flotation system of the utility model is: utilize high pressure solution gas principle, produce highdensity microbubble dissolved air water and mix with sewage, reach the object of removing oil slick, oil in water emulsion, suspended substance, COD in sewage.
By Bubble-floating Method is fine for the treatment of low-cloudy water effect, but for the higher former water treatment poor effect of turbidity; The precipitator method are just in time contrary with By Bubble-floating Method, in order to display one's respective advantages, cover the shortage, and the utility model combines air flotation pool and settling tank, make the interior existing pneumatically supported function of same device have again the function of precipitation.When the turbidity of water is higher, move by settling tank; Water flatly flows to end from top, swash plate district, and the shore pipe 5 of precipitating sludge at the bottom of by pond discharged, and water is precipitated clarification by swash plate 26.In the time that raw water turbidity is lower, in pond, front end passes into dissolved air water, and it is moved by air supporting mode, and the clear water after air supporting is flowed out by the rising pipe 11 on effluent trough 10, and the scum silica frost timing that above floats on the pond water surface is scraped into ash pit 9 by slag scraper 6, and scum pipe 8 is discharged.
Microbubble production process is: gas-liquid mixing pump 20 sucks air and the air flotation pool 7 end water purification after treatment of q.s, constantly convert the high pressure that produces 1.0-1.2Mpa under the squeezing action of volume at gas-liquid mixing pump 20 stators and rotor, along with the increase of pressure, the solubleness of air in water increases gradually, and part air is dissolved in water completely and reaches capacity.Surplus air and saturated dissolved gas water are in the time of the microbubble pipe 196 by microbubble generator 19, surplus air bubble is first through larynx hole and the fragmentation of collision bead two-stage, pass through again the third stage fragmentation of fixed teeth and spiral tooth, further by the continuous and crown collision in spiral stroke of surplus air bubble, cut and be crashed to pieces, reach 10 μ m left and right particle diameters, and with saturated dissolved gas water through reducing valve 22 control pressures within the scope of 0.4-0.6Mpa, keep the solubleness of air and reduce and the pressure reduction of the sewage pumping through lift pump 25 from former pond 24.Fully mix with saturated dissolved gas water, surplus air microbubble at the interior sewage of T-shaped mixing tank 2, microbubble Joint adsorption, the seizure of suspended substance in sewage, the particle diameter that oil particles is discharged by dissolved air water approximately 5 μ m and surplus air bubble 10 μ m form mixture, be discharged into evenly, slowly in air flotation pool 7 by dissolved air release 4 again, mixture is under the buoyancy of bubble, in air flotation pool, be floating trend with current, float to gradually liquid level and scraped to the interior separation of ash pit 9 by slag scraper 6.Water purification enters effluent trough 10 through ash pit 9 bottoms, finally completes purification by rising pipe 11 removal systems.
See Fig. 4, it is the structural representation of T-shaped mixing tank 2, T-shaped mixing tank 2 principle of work: the saturated dissolved gas water that gas-liquid mixing pump 20 produces tentatively mixes at T-shaped mixing tank 2 front ends at the interior release microbubble of T-shaped mixing tank 2 and with sewage by dissolved air water diffuser tube 201, microbubble starts to adhere to, catch suspended substance and oil particles in water simultaneously; Under the effect of cyclone flow deflector 202, the current motion of spinning, the movement travel that can increase current in limited space, strengthens mixed effect; Microbubble is at interior " gas bag water " the structure mixture that constantly forms gradually pollutent and bubble with suspended substance and oil particles collision, adhesion of T-shaped mixing tank 2, for follow-up mixture lays the foundation in the floating of air flotation pool.
Seeing Fig. 3, is the technological process schematic diagram of a kind of high-efficiency dissolved air flotation system of the utility model.Gas-liquid mixing pump 20 sucks air flotation pool 7 water purification after treatment through water inlet pipe 12, and by inlet pipe 14 air amounts, air is through gas meter 15 adjusting air inflow quantities, and line strainer 13 plays the effect of impurity in interception water, prevents damage equipment.In operational process, monitor negative pressure value in pipeline by vacuum meter 16, if exceed-0.04Mpa of negative pressure value, system stops automatically, to protect gas-liquid mixing pump 20.
Under the squeezing action of gas-liquid mixing pump 20 rotor-stators, produce high pressure saturated dissolved gas water, first pump into the import web plate 197 of microbubble generator 19, form again the microbubble of 5 μ m left and right by microbubble pipe 196, flow out microbubble generator 19 through outlet web plate 194 again, pressure unit 193 is respectively used to monitor microbubble generator 19 and imports and exports 198,195 pressure, exceed 1.2Mpa when importing and exporting 198,195 pressure, system is automatically out of service.
High pressure saturated dissolved gas water is measured by liquid pneumoelectric magnetic flowmeter 21, reduce pressure by reducing valve 22 again, fully mix T-shaped mixing tank 2 is interior with the sewage pumping by lift pump 25 from former pond 24, flow into dissolved air release 4 and at the interior release mixed solution of air flotation pool 7 by air flotation pool water inlet pipe 3.Due to density imbalance between liquid water mixture and liquid, produce buoyancy upwards, take suspended solid SS to the water surface.Scum silica frost on the water surface is scraped to ash pit 9 by slag scraper 6, discharges and collects through scum pipe 8, and at the bottom of pond, sediment is regularly discharged and processed from shore pipe 5.Water purification after treatment flow to effluent trough 10 and discharges air flotation pool 7 from rising pipe 11.
Claims (7)
1. a high-efficiency dissolved air flotation system, it is characterized in that, comprise air flotation pool, be arranged on slag scraper, slag discharging device and discharging device in air flotation pool, the gas-liquid mixing pump water inlet pipe of drawing from air flotation pool end, which is provided with inlet pipe, and connecting gas-liquid mixing pump, microbubble generator by gas-liquid mixed pipe, the high pressure saturated dissolved gas water pipe of drawing from microbubble generator is communicated with the dissolved air release of air flotation pool water inlet pipe end by T-shaped mixing tank with external sewage water inlet pipe.
2. a kind of high-efficiency dissolved air flotation system according to claim 1, is characterized in that, described air flotation pool is sloping plate deposition-air flotation pool, is provided with shore pipe at the bottom of pond.
3. a kind of high-efficiency dissolved air flotation system according to claim 1, is characterized in that, described slag scraper is chain-plate type slag scraper, and slag discharging device is made up of ash pit and scum pipe, and discharging device is made up of effluent trough and rising pipe.
4. a kind of high-efficiency dissolved air flotation system according to claim 1, is characterized in that, described gas-liquid mixing pump is mono-pump.
5. a kind of high-efficiency dissolved air flotation system according to claim 1, it is characterized in that, described microbubble generator by housing, be placed in the cluster type microbubble pipe in housing, import, outlet, vent valve and the pressure unit being located on housing forms, described import, outlet in be provided with web plate.
6. a kind of high-efficiency dissolved air flotation system according to claim 1, is characterized in that, described gas-liquid mixing pump water inlet pipe is provided with line strainer; Before inlet pipe, establish gas meter, on the pipeline after inlet pipe, establish vacuum meter; High pressure saturated dissolved gas water pipe is provided with magnetic flow meter and reducing valve.
7. a kind of high-efficiency dissolved air flotation system according to claim 1, is characterized in that, the other operation housing of establishing of described microbubble generator, realizes the chain control of the each device of system and valve by PLC.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420241163.4U CN203890088U (en) | 2014-05-12 | 2014-05-12 | Efficient dissolved air flotation system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201420241163.4U CN203890088U (en) | 2014-05-12 | 2014-05-12 | Efficient dissolved air flotation system |
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| CN203890088U true CN203890088U (en) | 2014-10-22 |
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| CN201420241163.4U Expired - Fee Related CN203890088U (en) | 2014-05-12 | 2014-05-12 | Efficient dissolved air flotation system |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103936093A (en) * | 2014-05-12 | 2014-07-23 | 辽宁华霆环保科技有限公司 | High-efficiency dissolved air flotation system |
| CN106395959A (en) * | 2016-11-02 | 2017-02-15 | 李伟 | Horizontal flow type automatic deslagging air-flotation device |
| CN106413903A (en) * | 2015-01-13 | 2017-02-15 | 罗兰·达曼 | Microflotation system having an expansion valve assembly and method for operating a microflotation system |
| CN114853260A (en) * | 2022-02-10 | 2022-08-05 | 上海市机电设计研究院有限公司 | Household-connected grey water treatment and recycling system and method in plain river network area |
-
2014
- 2014-05-12 CN CN201420241163.4U patent/CN203890088U/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103936093A (en) * | 2014-05-12 | 2014-07-23 | 辽宁华霆环保科技有限公司 | High-efficiency dissolved air flotation system |
| CN103936093B (en) * | 2014-05-12 | 2016-04-13 | 辽宁华霆环保科技有限公司 | A kind of high-efficiency dissolved air flotation system |
| CN106413903A (en) * | 2015-01-13 | 2017-02-15 | 罗兰·达曼 | Microflotation system having an expansion valve assembly and method for operating a microflotation system |
| CN106413903B (en) * | 2015-01-13 | 2019-06-21 | 罗兰·达曼 | Has the method for the micro- floatation equipment and the micro- floatation equipment of operation of pressure release valve device |
| CN106395959A (en) * | 2016-11-02 | 2017-02-15 | 李伟 | Horizontal flow type automatic deslagging air-flotation device |
| CN114853260A (en) * | 2022-02-10 | 2022-08-05 | 上海市机电设计研究院有限公司 | Household-connected grey water treatment and recycling system and method in plain river network area |
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Granted publication date: 20141022 Termination date: 20200512 |
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