Phosphorus Removal from Sewage with Biological Treatment

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Is it possible to remove phosphorus from sewage from 19 mg/l to 1 mg/l by biological means? 

How? Which biological treatment do you suggest? 

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33 Answers

  1. Yes is possible, by using ferric chloride in the process between Biological filter and Humus tank. The P will turn from 19 to 1mg/l.

     

    Thank you,

    Mangena P

  3. Enhanced Biological Phophorus Removal or EBPR configurations to activated sludge systems can enhance growth of PAOs,as bacteria that accummulate polyphosphates in large quantities,as they grow on nutrients in waste waters.

    EBPR configurations can selectively enrich PAOs,as polyphosphate accumulating systems for enhanced phosphate removal thru growth of microbial biomass in waste waters.

    EBPR is anaerobic aerobic system cofiguration,applied to activated sludge.

    Reference...Biological phosphorus removal manual..Utrecht,2002.

    Wastewater engg. Treatment..Metcalf ,Eddy Inc.,McGraw Hill.Boston

    • PAO are fantastic ways to remove phosphorus.    you can treat it down to 0.02 ppm. 
    • this is completely biological.  Phosphorus absorbing organisms. 

  5. Municipal wastewaters may contain from 5 to 20 mg/l of total phosphorous, of which 1-5 mg/l is organic and the rest in inorganic. The individual contribution tend to increase, because phosphorous is one of the main constituent of synthetic detergents. The individual phosphorous contribution varies between 0.65 and 4.80 g/inhabitant per day with an average of about 2.18 g. The usual forms of phosphorous found in aqueous solutions include:

     

    Orthophosphates: available for biological metabolism without further breakdown Polyphosphates: molecules with 2 or more phosphorous atoms, oxygen and in some cases hydrogen atoms combine in a complex molecule. Usually polyphosphates undergo hydrolysis and revert to the orthophosphate forms. This process is usually quite slow.(i.e., nutrient enrichment due to human activities) in surface waters are primarily due to nitrogen and phosphorus. The most recognizable manifestations of this phenomena are algal blooms that occur during summer. Over-nutrient enrichment results in low dissolved oxygen (DO), fish kills, murky water and depletion of desirable flora and fauna. In some cases toxic algae such as microsystis was found in algal blooms. In addition, the increase in algae increases the need to increase chlorine doses of drinking water, which in turn, leads to higher levels of disinfection by-products (that have been shown to increase the risk of cancer Excessive amounts of nutrients can also stimulate the activity of harmful microbes, such as Pfisteria.Phosphorous removal processes

    The removal of phosphorous from wastewater involves the incorporation of phosphate into TSS and the subsequent removal from these solids. Phosphorous can be incorporated into either biological solids (e.g. micro organisms) or chemical precipitates.

     

    Phosphate precipitation

     

    Chemical precipitation is used to remove the inorganic forms of phosphate by the addition of a coagulant and a mixing of wastewater and coagulant. The multivalent metal ions most commonly used are calcium, aluminium and iron.

     

    Calcium:

     

    it is usually added in the form of lime Ca(OH)2. It reacts with the natural alkalinity in the wastewater to produce calcium carbonate, which is primarily responsible for enhancing SS removal.

     

    Ca(HCO3)2 + Ca(OH)2 à 2CaCO3 ↓+ 2H2O

     

    As the pH value of the wastewater increases beyond about 10, excess calcium ions will then react with the phosphate, to precipitate in hydroxylapatite:

     

    10 Ca2+ + 6 PO43- + 2 OH- ↔ Ca10(PO4)*6(OH)2 ↓

     

    Because the reaction is between the lime and the alkalinity of the wastewater, the quantity required will be, in general, independent of the amount of phosphate present. It will depend primarily on the alkalinity of the wastewater. The lime dose required can be approximated at 1.5 times the alkalinity as CaCO3. Neutralisation may be required to reduce pH before subsequent treatment or disposal. Recarbonation with carbon dioxide (CO2) is used to lower the pH value.

     

    Aluminium and Iron:

     

    Alum or hydrated aluminium sulphate is widely used precipitating phosphates and aluminium phosphates (AlPO4). The basic reaction is:

     

    Al3+ + HnPO43-n ↔ AlPO4 + nH+

     

    This reaction is deceptively simple and must be considered in light of the many competing reactions and their associated equilibrium constants and the effects of alkalinity, pH, trace elements found in wastewater. The dosage rate required is a function of the phosphorous removal required. The efficiency of coagulation falls as the concentration of phosphorous decreases. In practice, an 80-90% removal rate is achieved at coagulant dosage rates between 50 and 200 mg/l. Dosages are generally established on the basis of bench-scale tests and occasionally by full-scale tests, especially if polymers are used. Aluminium coagulants can adversely affect the microbial population in activated sludge, especially protozoa and rotifers, at dosage rates higher than 150 mg/l. However this does not affect much either BOD or TSS removal, as the clarification function of protozoa and rotifers is largely compensated by the enhanced removal of SS by chemical precipitation.

    Ferric chloride or sulphate and ferrous sulphate also know as copperas, are all widely used for phosphorous removal, although the actual reactions are not fully understood. The basic reaction is:

     

    Fe3+ + HnPO43-n ↔ FePO4 + nH+

     

    Ferric ions combine to form ferric phosphate. They react slowly with the natural alkalinity and so a coagulant aid, such as lime, is normally add to raise the pH in order to enhance the coagulation.

     

     

     

     

  6. Hi Satyam,

    I would like to take up this challenge and propose Makro Organics treatment. We supply a patented, organic certified, plant extract product from South Africa. The product is marketed in UK, EU, South East Asia, UAE, Australia, Pakistan and soon India for the treatment of sewer effluent. In a recent application in Dubai, a independent 3rd party confirmed the results and we managed to reduce the phosphorus from around  5.0 to 0.4 in a limited retention system. We also managed to reduce P from 9.0 to 1.0  in another application on TSE. The treatment offers many other benefits for TSE. dave@makroorganics.com

     

  7. I can tell you that in an experiment I did during my master thesis, we were using biological treatment with MBBR technology. An anaerobic reactor was followed by an aerobic one (simple PAOs bacteria technology) and as carbon source for the anaerobic we used the carbon in the wastewater. The removal was good, but from 19 mg/l we never went down to 1mg/l; if I remember well it was something around 40-50% removal. Therefore I think you can't achieve that goal ONLY biologically, or at least unless you have a very complex system (maybe lots of Anaerobic/Aerobic couples of reactors with external carbon source, but this solution is a simple and probably wrong idea I had now). And even if you do, I don't think you can grant it always, especially if unwanted nitrification happens in the aerobic reactor.

  9. Enhanced biological phosphorus removal via luxury uptake after an anaerobic step is a well established technology applied at large scale in sewage treatment in the EU in spite of the low COD/TP and BOD/TP ratio's. In practice less than 2 mg/l can be achieved 100% biologically but to ensure maximum 1 mg/l in all conditions also chemical phosphorus precipitation would be needed from time to time.

  10. First prize is to use the natural micro-organisms already in the wastewater.  This is the whole principal around the biological nutrient removal processes.  The choice of which configuration is best for a particular application usually depends on the P to COD ratio, the sludge age, and other factors.  The configurations vary from BardenPho, UCT, Johannesburg, Modified Ludzak-Ettinger, and variations of these.  A precaution when dewatering the sludge is not to return the filtrate or supernatant back to the head of works as this often contains higher levels of P released by the microorganisms as they come under stress in the de-watering process.  Algae sounds very promising, but the algae need to be separated from the treated effluent which could be challenging - may require a DAF process.

  11. You have to waste biosolids to get P removal, no matter what kinds of the biological process. To get Bio-P removel to below 1 mg/L, the ratio of COD to TP should be more than 40 and with short sludge ages.

  12. I also come to understand that anaerobic-anoxic SBRhas superiority for aerobic -anaerobic ones more widely used

  13. Aerobic-anoxic SBR reported with use of nitrates for highly efficient phosphorus removal in wastewater

  14. you can use PAO to treat it to 0.2.  and then you can treat the biomass to phosphorus as  high as 14% to be reused for farming after checking for heavy metals.    i hope this helps

  15. I've been working on phosphorus removal by microalgae and we could less its concentration from 7ppm to 1.75.
    Depending on microalgae you choose, yes it can be possible to remove it.

  16. Hi,

    You can biologically remove this amount of P if the raw water has sufficient carbon and de-sludge from the process. Because the waste biomass normally contains 1 - 3% of P.

    If the raw wtaer has not sufficient BOD, the chemical P precipitation would be economic.

    1 Comment

  17. 1,500 mg of algae will consume 18 mg of P.  Growing algae is the best biological solution to remove P, provided adequate N is available, about 120 mg of N is required. 

    1 Comment

  18. Sir  ---  we have been using a 100% pure organic solution to remove phosphorus for about 20 years now.  Our product, Solutek has been used by a number of municipal authorities in WWTP for this purpose. We could ship you a sample to trial if you wish.

    See.....www.soleco-technology.com

    Email me.

    pettman@soleco-technology.com

    Hugh.

    1 Comment

  19. Biosol has been shown to remove influent phosphorus in the sewer from around 25 mg/L to about 4 mg/L. The phosphorus is precipitated and cannot be detected by the normal analysis means in Australia.  This precipitate end up in the sludge.  While Biosol's primary application is for odour and corrosion control in sewer systems, phosphorus removal is an additional benefit. Alum is used to remove the remaining phosphorus at the treatment plant.

  20. You might be interested in a technique to drop out the P in the wastewater by lowering the pH 2 pts and adding Magnesium (one of the most common elements of sea water).  The P will form a ball around an N molecule and precipitate out.

  21. Hello a question as complex worth thinking about.

    Talk about biological treatment - does absolutely nothing to say is completely abstract.

    There is no biological treatment - pour the simple reason that there is no treatment. You must add the mode or type of treatment as for example: treatment of purification.

    Bathroom and it is the misfortune of our time. The term - organic - means everything and say nothing, it is only a word that looks good on a text.

    Everything must be biological - to pay may be a biological purification plants --. FR rated XXIX effluent that must be pure of chemicals, and where all its features - biological - have been preserved, otherwise it is biochemical and the - biological - treatment cannot be done.Then perform a - biological treatment - to the tool and the place of purification.

    The tool, the nature the gives us as a whole, but because of the configuration of our sewage system, the tool is extremely rare.

    the place or container must also present - biological - features otherwise there is not treatment - biological-

    In nature biology is not specific to one element among many others. It's a whole. However when infrastructure includes impurities on a particular area, concentrations of pollution are so important that they are dangerous because unusable from the point of view of their treatment.If an idea came to transgress the nature it destabilize the biological harmony and nature cannot respond, turns everything into toxic mud. It is what often happens with the current system.

    Biology is able to take everything out unless he was given something exceptional natural.

  23. After having read and learned of so many wonderful techniques that make it possible to depollue the water that we use to improve our living conditions, the time has come to mobilize so that these means of depollution are applied so that no dirty water is Discharged into our rivers. It is also time to reward these innovators who do such beautiful things!

  24. Yes, Of course it is possible and desirable too to avoid chemicals. Look at Nutrem.  Juhani

  25. Further to my initial post and provide you maybe with a summary overview of our system technology:

    Description

    Our system hosts a diverse and large population of organisms capable of the degradation of aromatic and aliphatic hydrocarbons, chlorinated solvents and pesticides. The degraders become conditioned in the matrix which has a much slower decay rate than the pollutants that pass through. Furthermore sparingly soluble compounds such as large PAHs and PCBs are also effectively degraded. This is because the voids within the system are ideal habitats for a microbial ecosystem capable of utilising a diverse range of organic substrates. The niches within the matrix also have a range of REDOX potentials meaning that anaerobic and aerobic habitats exist side by side. Most significantly, the technology not only sorbs and retains these organic molecules but it is able to completely mineralise them rendering the end products of carbon dioxide and water

    Features

    • In-line waste water treatment

    • Novel and integrated solution

    • Work with and enhance existing processes

    • Streamline wastewater treatment and enhance commercial and environmental sustainability

    • “Green solution” to industrial wastewater challenges

     

    Removes the following:

    • BOD Up to 95% 
    • COD Up to 95% 
    • Ammonium Up to 90% 
    • Arsenic Up to 95% 
    • Chromium Up to 99% 
    • Copper Up to 99% 
    • Chlorinated Solvents Up to 99% 
    • Explosives Up to 99% 
    • Mercury Up to 95% 
    • Phenoxyacid herbicides Up to 99% 
    • Uranium Up to 99% 
    • Zinc UP to 95%

    1 Comment

  26. By dosing ferric chloride it can help. Firstly you need to determine Alkalinity and if Alkalinity is 20mg/l meaning the dosing rate of ferric it will be 20mg/ls

  30. Yes phosphorous can be removed from sewage. We deal with Genetically Modified Bacteria. Along with this and our MAST Technology wastewater treatment where we use Microalgae it is possible to attain the target effluent values that you wish to attain. 

    In case you wish to get more information you can reach me at advenvtech@gmail.com. I am based at Mumbai and we will be shortly starting a 12 mld wastewater facility in one of the western states of India. 

  31. Good Afternoon,

    We have technology that can remove the phosphorous and recover the phosphate.

    Where are you located?

    I would suggest eqs for Europe at 2 mg/l is more easily achievable and meets legal threshold.

  32. To recommend a biological or non-biological approach, I would need more information on he influent makeup. BNR of phosphate requires short-chain organic acids in the anaerobic step and is also sensitive to the presence of nitrate/nitrite. Often with high influent phosphate, you are best served by using combined biological and tertiary chemical treatment.

    1 Comment

    1. Bonjour

      Il est impossible d'effectuer un traitement -biologique- sur des effluents chimiques. c'est une hérésie. 

      Pour faire du traitement il faut déjà définir quel genre de traitement comme par exemple un traitement d'épuration. Hors tous les systèmes actuels n'ont aucune vocation d'épurer, il s'agit simplement d'une gestion des excréments. Pour preuve la production mondiale de résidus de boue d'excréments en sorti des STEP est de plus de 45 millions de tonnes. ou est l'épuration?

      Si on ne peut pas faire -du biologique- avec des effluents chimiques, il faut aussi expliquer en quoi consite le sans oxygène. L'eau est composée de H2O. Là ou il y a de l'eau il y a de l'O2. A quel momment et par quelle action un effluent aérobie devient-ils sans oxygène. Ou se situe la barrière entree l'aérobie et la sans oxygène?

       

      Hello

      It is impossible to perform a - biological - treatment on chemical effluent. It is a heresy. 

      Do the processing to already define what kind of treatment as for example a purification treatment. Off all current systems have no vocation to purify, it is simply management of feces. For evidence world production of residues of mud of excrement out of the STEP is over 45 million tonnes. or is the treatment?

      Can't do - organic - chemical effluent, with should also explain what consists the without oxygen. Water is composed of H2O. Where there is water there is O2. At what moment and by what action an aerobic effluent becomes - they without oxygen. Where is located the entry barrier aerobics and without oxygen?

       

  33. Yes....BardenpHo, AO, AO2 etc....or  just use  a  non-propiatary  anaerobic  zone at  head  of  aeration as  described in WEF Nutrient  control  manual or  MOP 8