Foaming of Effluent in WWTP

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In out wastewater treatment plant we have constructed huge Imhoff tanks for treatment of wastewater.

Besides very high H2S odour, the effluent wastewater had severe foaming.

What is causing the foam?

Can the possible reason be the ammonium generated from anaerobic processes?

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14 Answers

  3. If you are getting substantial COD and solids removal across the Imhoff tank, it is working well. High influent sulfate does lead to organisms that produce H2S under anaerobic conditions such as the sludge layer. This is just natural to the process.

    Detergents are not decomposed in the Imhoff treatment tank and will cause foaming. Foam can also be attributed to soluble intermediates from the tank's microbial population.

  4. Bonjour

    Les excréments sont constitués d'urine qui au contact de l'oxygène se transforme ou produit de l'ammoniaque.

    Les eaux usées contiennent différentes pollutions d'origine chimique en plus de la pollution d'origine biochimique.

    Chaque polluant inter-agit sur les autres polluants en plus du facteur principale qui est l'oxygène.

    Quand on sait en plus que sur une STEP il n'existe aucun dispositif d'épuration toute cette pollution est rejetée, dispersée dans l'environnement.

    Bien entendu avec un impact à plus ou moins long terme sur la santé de l'homme.

     

    Hello

    Feces consist of urine which in contact with the oxygen turns or product ammonia.

    Wastewater contain different impurities of chemical origin in addition to the pollution of biochemical origin.

    Each pollutant inter-agit on other pollutants in addition to the main factor which is oxygen.

    When you know more about a STEP there is no purification device all this pollution is rejected, dispersed in the environment.

    Of course, with a more or less long term on the human health impact.

  5. If this is truly an Imhoff tank as you say, then the odors and the foaming are the result of anaerobic activity on the bottom of the Imhoff tank. In actuality, it is working as designed. That's why they're not used much

  6. If the only treatment process you have are the Imhoff Tanks then it is used for the clarification of sewage by simple settling and sedimentation, along with anaerobic digestion of the settled sludge. That's it..no activated sludge foaming, etc.. The previous comment on wastewater content (shampoo, surfactants, etc.) is more valid.

    Another discussion group's input may be helpful:

    https://www.researchgate.net/post/What_causes_severe_foaming_of_effluent_from_Imhoff_tanks

  8. Kattrina,

    First check the colour and density of the foam. If it is brown and dense it is probably caused by filamentous bacteria. If it is light and white then it is likely to be an organic residue from incomplete treatment of the wastewater, often created under anaerobic conditions.

    In either case you need to get the conditions right to fix the problem. Don't waste money on buying bacteria or chemicals to "fix" the problem as this will only be a short-term measure.

  9. Bonjour 

    Dans ce genre de -gestion- des eaux usées il n'existe aucune épuration. il s'agit uniquement d'un processus séparatif des matières du liquide. La fonction d'épuration définit qu'il existe une action d'abattement entre l'entrée et la sortie d'un dispositif. Hors à ce jour toutes les usines de gestion des eaux usées produisent des quantités phénoménales de résidus boueux. Plus de 45 millions de tonnes de boue d'excréments sont produites annuellement par ce genre de station.

    Un effluent normal provenant d'une habitat à usage domestique produit un effluent -biologique- si les usagers de l'eau, n'y injectent aucun produits chimiques. Ce qui bien entendu est loin d'être le cas en assainissement collectif.

    Ce qui fait que les effluents qui arrivent sur la STEP sont :

    - Biochimique

    - les caractéristiques -biologique- des effluents ont disparus: c'est de la boue liquide.  

    La boue ou les résidus boueux sont le résultat ultime de la transformation de la matière organique en boue par le processus de la putréfaction. Dans ce cas, le processus de biodégradation par les micros organismes ne se pratique plus.

    La putréfaction est le processus de destruction de toute matière organique -vivante- qui a perdue ces caractéristiques -biologique-. C'est un élément mort, inerte.

    Le phénomène de putréfaction est activé par la méthanisation du milieu, d'où l'origine des émanations pestilentielles de vos réservoirs. Ce qui se produit dans toutes les STEP du monde car toutes utilisent le même principe de gestion séparatif.

    Le lquide des effluents d'eaux usées contient de l'urine dont l'urée se transforme en ammoniaque au contact de l'Oxygène. Le bassin d'aération dit boue activée augmente ce phénomène et provoque encore plus la putréfaction.

    Le chimique contenu dans les effluents d'eaux usées de l'assainissement collectif fait de ces effluents une bombe atomique. Le bassin d'aération est là pour tuer l'explosion. Bien entendue la boue activée n'a pas du tout le sens que l'on veut bien lui donner.  

    Un effluent d'eaux usées contient de l'eau < H2O > tant qu'il y a de l'eau, donc de l'oxygène il ne peut pas y avoir de -sans oxygène-. Donc s'il ne peut pas y avoir de -sans oxygène, il ne peut pas y avoir d'anaérobie.

    Toute la partie supérieures des effluents est au contact de l'air ambiant qui elle est AEROBIE.

    A quel endroit , pour quel motif, comment s'effectue la modification, quel est la barrière qui délimite les deux zones oxygène et sans oxygène, ? on voit bien que tout cela n'est que de la litérature .

     

    English

     In this kind of - management - sewage there is no treatment. This is only a divisive process of the liquid contents. The function of purifying sets there is an action of reduction between the input and output of a device. Off to date all wastewater management plants produce incredible amounts of muddy residue. More than 45 million tons of mud of excrement are produced annually by this kind of station.Normal effluent from a habitat for domestic use produced an effluent - biological - if water users, don't inject there no chemicals. Which of course is far from being the case in mains.

    What makes the effluent entering the STEP are:

    -Biochemical - the - organic 

    - characteristics of effluents have disappeared: it's liquid mud.

    Mud or muddy residue are the ultimate result of the transformation of organic matter into mud by the process of putrefaction. In this case, the process of biodegradation by the microphones agencies do more practice.

    Putrefaction is the process of destruction of all organic matter - alive - who lost these characteristics - biological-. It's a dead, inert element.

    The phenomenon of putrefaction is activated by the methanisation of the Middle, where the origin of the pestilent emanations of your tanks. What happens in every STEP of the world because all use the same divisive management principle.

    The lquide of wastewater effluent contains urine which turns the urea into ammonia in contact with oxygen. The aeration said active mud basin increases this phenomenon and still causes rot

    The chemical contained in the effluents of sewage collective sanitation of these effluents an atomic bomb. The aeration basin is there to kill the explosion. Heard mud activated didn't all the sense that we want to give it.

    A sewage effluent contains < H2O> water as long as there is water, so oxygen it cannot be -without oxygen- . So if it can't be -without oxygen- , there may not be of anaerobic.

    All the upper part of the effluent is in contact with air it is AEROBIC.

    Where and for what reason, how does the change, what is the barrier that demarcates the two zones of oxygen without oxygen? clearly that all this is only literature.

     

    1 Comment

  12. Dear Kattrina

    There are a few questions clarifications required 

    1) Source of wastewater and incoming pollution load and flow rate

    2) Process scheme or process flow chart

    3) is it a new phenomena occurring now or since the beginning of your wastewater treatment plant? If this is a new phenomena then you need to look into what cha fed in the factory processing has been done causing the wastewater characteristic changes. Either to eliminate that change or review the scheme...

    4) we could then realise the main reasons for excess foaming matter once we know the answers above.

     

     

     

  13. Activated sludge systems are prone to be affected by foaming occurrences causing the sludge to rise in the reactor and affecting the wastewater treatment plant (WWTP) performance. Nonetheless, there is currently a knowledge gap hindering the development of foaming events prediction tools that may be fulfilled by the quantitative monitoring of AS systems biota and sludge characteristics. I know there was a study done by Neeri for novel “Novel application of bacteriophage for controlling foaming in wastewater treatment plant- an eco-friendly approach “ includes characteristics of the phages NOC1, NOC2 and NOC3 not discussed in the previous paper. The phage adsorption and host interaction properties, their sensitivity to pH and temperature are inferred.

    You may find that study useful.

  14. Foaming in activated sludge process is a common operational problem in many wastewater treatment plants. The foam can occur in aeration tank, secondary clarifier, as well as in anaerobic digester. Foam in WWTP is normally sticky, viscous and brown in color. It floats and accumulates on top of the tanks, and can take up a large fraction of solids inventory and reactor volume, thus decreasing the effluent quality and control of sludge retention time (SRT).
    In your case, Low possibility of anoxic conditions, because the Imhoff is more anaerobic then anoxic reactor and also this kind of foam i observed at the effluent from covered circular classifiers, same with H2S smell ->probably in these settler the sludge take out occurred in rare occasions and turned into a quasi A.D.