CH658044A5 - METHOD FOR REMOVAL OR PREVENTING CLOGS IN DEEP AERATORS IN WATER TREATMENT AND WATER TREATMENT UNDER OPERATING CONDITIONS. - Google Patents
METHOD FOR REMOVAL OR PREVENTING CLOGS IN DEEP AERATORS IN WATER TREATMENT AND WATER TREATMENT UNDER OPERATING CONDITIONS. Download PDFInfo
- Publication number
- CH658044A5 CH658044A5 CH5493/82A CH549382A CH658044A5 CH 658044 A5 CH658044 A5 CH 658044A5 CH 5493/82 A CH5493/82 A CH 5493/82A CH 549382 A CH549382 A CH 549382A CH 658044 A5 CH658044 A5 CH 658044A5
- Authority
- CH
- Switzerland
- Prior art keywords
- aerators
- chemical
- gas
- operating conditions
- water treatment
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F5/00—Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents
- C02F5/08—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents
- C02F5/10—Treatment of water with complexing chemicals or other solubilising agents for softening, scale prevention or scale removal, e.g. adding sequestering agents using organic substances
-
- 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
- C02F3/20—Activated sludge processes using diffusers
-
- 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
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Water Supply & Treatment (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Biodiversity & Conservation Biology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Microbiology (AREA)
- Aeration Devices For Treatment Of Activated Polluted Sludge (AREA)
- Treating Waste Gases (AREA)
- Feeding, Discharge, Calcimining, Fusing, And Gas-Generation Devices (AREA)
- Biological Treatment Of Waste Water (AREA)
- Activated Sludge Processes (AREA)
- Physical Water Treatments (AREA)
Description
Die Erfindung bezieht sich auf ein Verfahren zur Beseitigung bzw. Verhinderung von Verstopfungen in Tiefenbelüftern bei der Wasseraufbereitung und Abwasserbehandlung unter Betriebsbedingungen. The invention relates to a method for eliminating or preventing blockages in deep aerators in water treatment and waste water treatment under operating conditions.
Tiefenbelüfter, d.h. Belüfter, die nahe dem Boden des Belüftungsbeckens angeordnet sind, haben einen geringeren Energiebedarf und ein besseres Lufteintragevermögen als seitlich im Belüftungsbecken angeordnete Belüfter. Deep aerator, i.e. Aerators which are arranged near the bottom of the aeration basin have a lower energy requirement and a better air intake capacity than aerators arranged laterally in the aeration basin.
Beim Betrieb von Belüftungssystemen in Wasseraufberei-tungs- oder Abwasserbehandlungsanlagen bilden sich in den Poren der Belüfter nach kürzerer oder längerer Zeit Ablagerungen. Sie bestehen in der Regel zur Hauptsache aus Calciumcarbonat und/oder Eisenphosphat und/oder organischen Stoffen. Wie rasch diese Ablagerungen zur Verstopfung der Belüfter führen, hängt nicht nur von dem Material, aus dem die Belüfter hergestellt sind (z.B. verschiedene Kunststoffe, wie Polyäthylen, Polypropylen oder Polystyrol, oder keramische Sintermaterialien), und dem Luftdurchsatz, sondern in erster Linie von der Zusammensetzung des zu behandelnden Wassers ab. Die Ablagerungen beeinträchtigen das Sauerstoffeintragevermögen der Belüfter und verursachen eine Erhöhung des Energieverbrauchs. Sie treten sowohl bei sogenannten Tellerbelüftern (Filterdomen) als auch bei Kerzenbe-lüftern auf. When operating ventilation systems in water treatment or wastewater treatment plants, deposits form in the pores of the aerators after a shorter or longer period of time. They usually consist mainly of calcium carbonate and / or iron phosphate and / or organic substances. How quickly these deposits lead to the blockage of the aerators depends not only on the material from which the aerators are made (e.g. various plastics such as polyethylene, polypropylene or polystyrene, or ceramic sintered materials) and the air flow rate, but primarily on the Composition of the water to be treated. The deposits impair the oxygen carrying capacity of the aerators and cause an increase in energy consumption. They occur with so-called plate aerators (filter domes) as well as with candle aerators.
Zur Reinigung von Tiefenbelüftern musste bisher folgen-dermassen vorgegangen werden: Das Belüftungsbecken wurde entleert, die Belüfter wurden ausgebaut, eingeweicht und gewaschen (in einem Säurebad, das meist aus Salzsäure bestand) und wieder eingebaut und das Becken wieder in Betrieb genommen. Da die Belüftungsbecken bis zu 1000 oder mehr Tellerbelüfter enthalten können, ist dieses Vorgehen sehr mühsam und zeitraubend. Ausserdem wird dadurch das Funktionieren von Kläranlagen beeinträchtigt, oder das Abwasser muss sogar an ihnen vorbeigeführt werden. In gewissen Anlagen muss eine solche Reinigung mehrmals im Jahr erfolgen. Up to now, the following steps had to be taken to clean deep aerators: The aeration basin was emptied, the aerators were removed, soaked and washed (in an acid bath, which mostly consisted of hydrochloric acid) and reinstalled, and the basin was put into operation again. Since the aeration tanks can contain up to 1000 or more plate aerators, this procedure is very tedious and time-consuming. In addition, the functioning of sewage treatment plants is impaired, or the waste water even has to be led past them. In certain systems, such cleaning has to be done several times a year.
Es gibt auch schwenkbare Belüftersysteme, die zur Reinigung aus dem Belüftungsbecken herausgeschwenkt werden können, doch sind derartige Systeme wegen der erforderlichen Gelenkverbindungen teuer. There are also pivotable aerator systems that can be swung out of the aeration basin for cleaning, but such systems are expensive because of the articulation required.
Die Erfindung ermöglicht nun die Beseitigung bzw. Verhinderung von Verstopfungen in Tiefenbelüftern unter Betriebsbedingungen, ohne dass die Belüfter ausser Betrieb gesetzt werden müssen. Das erfindungsgemässe Verfahren ist einfach und kann in kurzen Zeitabständen oder auch kontinuierlich durchgeführt werden, wodurch erhebliche Einsparungen an Belüftungsenergie möglich sind. The invention now enables the elimination or prevention of blockages in deep aerators under operating conditions without the aerators having to be taken out of operation. The method according to the invention is simple and can be carried out at short time intervals or continuously, whereby considerable savings in ventilation energy are possible.
Das erfindungsgemässe Verfahren ist dadurch gekennzeichnet, dass man eine Chemikalie, die das verstopfende Material mindestens zum Teil in eine Form überführt, die in dem aufzubereitenden Wasser oder dem zu behandelnden Abwasser löslich ist, in das den Belüftern zuzuführende Gas einführt, ohne dass die Belüfter ausser Betrieb gesetzt werden. The process according to the invention is characterized in that a chemical which at least partially converts the clogging material into a form which is soluble in the water to be treated or the waste water to be treated is introduced into the gas to be supplied to the aerators without the aerators being excluded Operation.
Das den Belüftern zuzuführende Gas ist in der Regel Luft oder Sauerstoff, z.B. Druckluft. Die Chemikalie wird vorzugsweise in Gas- oder Dampfform zugeführt, kann aber auch als feiner Spray eingeführt werden. The gas to be supplied to the aerators is usually air or oxygen, e.g. Compressed air. The chemical is preferably supplied in gas or vapor form, but can also be introduced as a fine spray.
Zweckmässig führt man die Chemikalie mittels einer Dosiervorrichtung in das den Belüftern zuzuführende Gas ein. Die Dosiervorrichtung kann z.B. aus einer Hochdruckpumpe mit einer kleinlöchrigen Düse bestehen, wodurch die Chemikalie als feines Aerosol in das Gas gemischt wird, wie dies bei Hochdruckfarbenzerstäubern der Fall ist. Es kann sich auch um eine Pumpe mit einem Beschickungsrohr handeln; auf diese Weise können leichflüchtige oder gasförmige Chemikalien eingeführt werden. Vorzugsweise dosiert man die Chemikalie aber mittels einer Pumpe und eines Vergasers, z.B. eines Leckvergasers, Schwimmervergasers oder Einspritzvergasers, in das Gas ein. Dadurch ist gewährleistet, dass sich in dem Gasverteilnetz keine unvergasten Chemikaliendämpfe abscheiden, sondern die Chemikaliendämpfe gleichmässig auf die einzelnen Belüfteraggregate verteilt werden. Man kann auch Kombinationen derartiger Dosiervorrichtungen anwenden. The chemical is expediently introduced into the gas to be supplied to the aerators by means of a metering device. The dosing device can e.g. consist of a high-pressure pump with a small-hole nozzle, whereby the chemical is mixed into the gas as a fine aerosol, as is the case with high-pressure paint atomizers. It can also be a pump with a feed pipe; in this way volatile or gaseous chemicals can be introduced. However, the chemical is preferably metered by means of a pump and a gasifier, e.g. a leak gasifier, float gasifier or injection gasifier into the gas. This ensures that no gassed chemical vapors separate in the gas distribution network, but the chemical vapors are evenly distributed over the individual aerator units. Combinations of such metering devices can also be used.
Die Chemikalie kann vor oder nach dem Kompressor in die Gaszufuhrleitung, vorzugsweise eine Druckluftleitung, eingeführt werden. Z.B. kann die Chemikalie in das Haupt-gasverteilungsrohr oder in das Zufuhrrohrsystem der einzelnen Belüftersektoren zugeführt werden. The chemical can be introduced into the gas supply line, preferably a compressed air line, before or after the compressor. E.g. the chemical can be fed into the main gas distribution pipe or into the feed pipe system of the individual aerator sectors.
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Geeignete Chemikalien sind unter den Betriebsbedingun- der Belüfter, dem Luftdurchsatz und der Art des zu behangen flüchtige Säuren, wie Salzsäure und Ameisensäure, oder delnden Abwassers abhängt. Suitable chemicals depend on the operating conditions of the aerator, the air flow rate and the type of volatile acids to be covered, such as hydrochloric acid and formic acid, or delta wastewater.
unter den Betriebsbedingungen flüchtige Basen, wie Ammo- Mittels des erfindungsgemässen Verfahrens können starke niak, oder auch Gase, wie Schwefeldioxyd oder Kohlendio- Verstopfungen der Belüfter schon nach einer Behandlungszeit xyd, sowie Flüssigkeiten, die vorzugsweise wässrig sind. Ein s von wenigen Stunden gelöst werden, so dass der Druckverlust Beispiel einer solchen Flüssigkeit ist eine wässrige Lösung ei- an den Belüftern in der Regel nahezu auf den Wert von neuen nes Chelatbildners, wie Äthylendiamintetraessigsäure. Belüftern abnimmt. Die Chemikalie kann aber auch dauernd bases which are volatile under the operating conditions, such as ammonia, can be used in the process according to the invention to give strong niac, or even gases, such as sulfur dioxide or carbon dioxide clogging of the aerators after a treatment time xyd, and also liquids which are preferably aqueous. As s of a few hours can be solved so that the pressure loss. An example of such a liquid is an aqueous solution at the aerators usually close to the value of new chelating agent such as ethylenediaminetetraacetic acid. Aerator decreases. The chemical can also be permanent
Ameisensäure ist sehr geeignet, da sie biologisch abbaubar in geringeren Mengen zudosiert werden, wodurch Verstop-und in bezug auf die Belebtschlamm-Biozönose von Abwas- fungen der Poren wirkungsvoll verhindert werden. Geeignete serbehandlungsanlagen ungiftig ist. In Betracht kommt 1- bis io Mengen können leicht durch Versuche ermittelt werden. 100%ige Ameisensäure. Bevorzugt wird 50- bis 85%ige Da bei schwach gepuffertem Wasser, z.B. weichem Was- Formic acid is very suitable, since it is added in smaller amounts to biodegradable substances, which effectively prevents clogging and, in relation to the activated sludge biocenosis, from wetting of the pores. Suitable water treatment plants is non-toxic. Possible 1- to 10 quantities can easily be determined by experiment. 100% formic acid. 50-85% Da is preferred in the case of weakly buffered water, e.g. soft was-
Ameisensäure, insbesondere 8 5 %ige technische Amei- ser, der pH-Wert des zu behandelnden Wassers bei Zusatz sensäure. grösserer Säuremengen zu stark ansteigen könnte, gibt man in Formic acid, especially 8 5% technical ants, the pH value of the water to be treated with the addition of sensic acid. larger amounts of acid could increase too much, one gives in
Eine geeignete Dosierung der Chemikalie muss durch Ver- solchen Fällen zweckmässig Puffer, wie Natriumbicarbonat, suche ermittelt werden, da sie naturgemäss von dem Material is in das Belüftungsbecken. A suitable dosage of the chemical must be ascertained by such cases, appropriately looking for buffers such as sodium bicarbonate, since it naturally flows from the material into the aeration tank.
C C.
Claims (10)
Priority Applications (10)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH5493/82A CH658044A5 (en) | 1982-09-16 | 1982-09-16 | METHOD FOR REMOVAL OR PREVENTING CLOGS IN DEEP AERATORS IN WATER TREATMENT AND WATER TREATMENT UNDER OPERATING CONDITIONS. |
CA000436717A CA1203328A (en) | 1982-09-16 | 1983-09-14 | Method for the elimination or prevention of blockages in bottom aerators in water treatment and sewage treatment under operating conditions |
SE8304939A SE8304939L (en) | 1982-09-16 | 1983-09-14 | WANT TO PREVENT BLOCKING OF AIR |
GB08324649A GB2130570B (en) | 1982-09-16 | 1983-09-14 | Method for the elimination or prevention of blockages in bottom aerators in water treatment and sewage treatment under operating conditions |
IT4898183A IT1170498B (en) | 1982-09-16 | 1983-09-15 | PROCEDURE TO ELIMINATE OR PREVENT THE BLOCKING OF BOTTOM AERATORS IN THE TREATMENT OF WATERS AND DISCHARGES |
AT0331083A AT392061B (en) | 1982-09-16 | 1983-09-16 | METHOD FOR REMOVAL OR PREVENTING CLOGS IN DEEP AERATORS IN WATER TREATMENT AND WATER TREATMENT UNDER OPERATING CONDITIONS |
FR8314760A FR2533207B1 (en) | 1982-09-16 | 1983-09-16 | PROCESS FOR THE ELIMINATION OR THE PREVENTION OF CLOGGING IN FUND AERATORS IN THE TREATMENT OF WATER AND THE TREATMENT OF WASTEWATER IN OPERATING CONDITIONS |
FI833316A FI76061C (en) | 1982-09-16 | 1983-09-16 | Procedure for removing or preventing clogging of the bottom air in water treatment and wastewater treatment during operation |
DE19833333602 DE3333602A1 (en) | 1982-09-16 | 1983-09-16 | METHOD FOR REMOVAL OR PREVENTING CLOGS IN DEEP AERATORS IN WATER TREATMENT AND WATER TREATMENT UNDER OPERATING CONDITIONS |
CS836781A CS248709B2 (en) | 1982-09-16 | 1983-09-16 | Removing or preventing method of choking of the depth aerators |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH5493/82A CH658044A5 (en) | 1982-09-16 | 1982-09-16 | METHOD FOR REMOVAL OR PREVENTING CLOGS IN DEEP AERATORS IN WATER TREATMENT AND WATER TREATMENT UNDER OPERATING CONDITIONS. |
Publications (1)
Publication Number | Publication Date |
---|---|
CH658044A5 true CH658044A5 (en) | 1986-10-15 |
Family
ID=4294516
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CH5493/82A CH658044A5 (en) | 1982-09-16 | 1982-09-16 | METHOD FOR REMOVAL OR PREVENTING CLOGS IN DEEP AERATORS IN WATER TREATMENT AND WATER TREATMENT UNDER OPERATING CONDITIONS. |
Country Status (10)
Country | Link |
---|---|
AT (1) | AT392061B (en) |
CA (1) | CA1203328A (en) |
CH (1) | CH658044A5 (en) |
CS (1) | CS248709B2 (en) |
DE (1) | DE3333602A1 (en) |
FI (1) | FI76061C (en) |
FR (1) | FR2533207B1 (en) |
GB (1) | GB2130570B (en) |
IT (1) | IT1170498B (en) |
SE (1) | SE8304939L (en) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3545194A1 (en) * | 1985-12-20 | 1987-07-02 | Sennheiser Electronic | Opto-electronic transceiver |
US5140203A (en) * | 1988-09-27 | 1992-08-18 | Mannesmann Rexroth Gmbh | Control motor for a servo-valve |
DE19952135A1 (en) * | 1999-10-29 | 2001-06-13 | Messer Griesheim Gmbh | Waste water treatment process |
AT411359B (en) * | 2002-01-17 | 2003-12-29 | Frey Wilhelm | CLEANING PROCEDURE AND CLEANING LIQUID FOR FAN BODY |
CN115417492B (en) * | 2022-08-30 | 2023-06-20 | 同济大学建筑设计研究院(集团)有限公司 | Advanced oxidation system based on underwater vision and control method |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2686138A (en) * | 1951-09-15 | 1954-08-10 | Chicago Pump Co | Method for cleaning diffuser plates |
GB1281334A (en) * | 1968-08-01 | 1972-07-12 | British Steel Corp | Biological purification of coke oven effluent |
US4199469A (en) * | 1978-06-21 | 1980-04-22 | Feldmann Chemie | Composition and method for cleaning drinking water tanks |
FR2469450A1 (en) * | 1979-11-12 | 1981-05-22 | Solitaire Produits Entretien F | Aq. aerosol descaling and cleaning compsn. - contg. organic acid, surfactant, gelling agent and hygroscopic agent |
JPS57117397A (en) * | 1980-09-11 | 1982-07-21 | Sterling Drug Inc | Method of removing scale from tile for deffusion of waste water disposal device |
US4382867A (en) * | 1980-09-29 | 1983-05-10 | Water Pollution Control Corp | In place gas cleaning of diffusion elements |
-
1982
- 1982-09-16 CH CH5493/82A patent/CH658044A5/en not_active IP Right Cessation
-
1983
- 1983-09-14 SE SE8304939A patent/SE8304939L/en not_active Application Discontinuation
- 1983-09-14 GB GB08324649A patent/GB2130570B/en not_active Expired
- 1983-09-14 CA CA000436717A patent/CA1203328A/en not_active Expired
- 1983-09-15 IT IT4898183A patent/IT1170498B/en active
- 1983-09-16 CS CS836781A patent/CS248709B2/en unknown
- 1983-09-16 FR FR8314760A patent/FR2533207B1/en not_active Expired
- 1983-09-16 FI FI833316A patent/FI76061C/en not_active IP Right Cessation
- 1983-09-16 AT AT0331083A patent/AT392061B/en not_active IP Right Cessation
- 1983-09-16 DE DE19833333602 patent/DE3333602A1/en active Granted
Also Published As
Publication number | Publication date |
---|---|
GB2130570B (en) | 1986-09-17 |
ATA331083A (en) | 1990-07-15 |
FI76061C (en) | 1989-05-30 |
IT8348981A0 (en) | 1983-09-15 |
FI833316A0 (en) | 1983-09-16 |
GB2130570A (en) | 1984-06-06 |
CS248709B2 (en) | 1987-02-12 |
FR2533207B1 (en) | 1986-09-19 |
FI833316A (en) | 1984-03-17 |
DE3333602C2 (en) | 1991-06-06 |
SE8304939L (en) | 1984-03-17 |
DE3333602A1 (en) | 1984-03-22 |
IT1170498B (en) | 1987-06-03 |
FI76061B (en) | 1988-05-31 |
CA1203328A (en) | 1986-04-15 |
FR2533207A1 (en) | 1984-03-23 |
AT392061B (en) | 1991-01-25 |
SE8304939D0 (en) | 1983-09-14 |
GB8324649D0 (en) | 1983-10-19 |
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