Micro organism removed by membranes, scientific reports

I am in need of independent scientific test reports to proof the efficency of membranes in removing virus and bacteria. 

Your help much appreciated. 

Taxonomy

• Purification
• Membranes
• Research
• Purification Specialist
• Water Quality Research
• Membrane

8 Answers

1. 1.You may test the total plate counting, to check the bacteria before and after the ​membranes.

   2.The virus could not remove by membranes, because of size of virus is too small to filter.

2. We have utilized RO membranes for extraction of reuse quality water from effluents in a number of cases. The extracted water in some cases was to be used for fermentation purpose. The production chemists were skeptic about suitability of such recovered water for fermentation, fearing contamination. In view of their reluctance, we carried out special microbiological analysis of the same. We found that immediately after emergence of permeate (i.e. recovered reuse quality water) from Membranes, it was completely sterile. Secondly the same permeate, was kept for few hours & for a day. The microbiological contamination was absent for few hours. The contamination arose only after storage of the extracted water (i.e. permeate) for a day or so, for obvious reasons. This experiment was carried out at number of different sites & at different effluents. The results were same. The permeate was completely sterile immediately after emergence from membranes. Of course the sampling in such experiments must be done into sterile containers & fully observing the guidelines for such sampling.

   In general, as regards membranes, the microbiological contamination gets cut off by using Ultrafiltration, Nanofiltration & Reverse Osmosis. However microfiltration membranes do not cut off the microbiological contamination. 

   Hope this is useful for your purpose. The proof of the pudding is in eating. So we carried out actual experiments to verify the desired.  

3. Practical experience has shown that bacteria can grow through RO membranes and due to the size will not remove viruses due to pore size.  They will reduce bacterial numbers so disinfect but the higher the numbers before the membrane the more will be found afterwards.  UV after the membranes will inactivate viruses and again reduce bacterial numbers but unless a material such as chlorine is used after that there is nothing to prevent growth of bacteria after UV.  Neither RO nor UV have a residual effect.  It does depend on what you are trying to achieve.

4. You can search information with Reverse Osmosis Process.

   Regards.

5. Also please search the topic nano   fibrous membrane u will get many research papers . I'm sure.

6. There has been many independent researches undertaken to prove the effectiveness of different membranes to remove bacteria and viruses. Initial researches showed removal of bio films using various membranes just like process of osmosis/ reverse osmosis. With improvement in nano technology , Nano fibre membrane have been found to be somewhat effective in filtering bacteria and virus. Hope this helps . Thank you

7. Membranes are subject to bio fouling and can accumulate bacteria and micro organisms on the surface which might slip through the membrane to the permeate. Therefore to use only membrane as disinfectant is not recommendable. Always have another disinfection method after the membranes in case you want to produce drinking water. I can recommend Quantum technology filters from Claire Industry or the traditional ways like UV light, Ozone or Chlorine Dioxide in order to assure micro biological safety of the permeate.

    

8. One place I would look is with data from the Orange County Water District (OCWD), in Orange County, CA.  There has been so much published in the peer review literature that you shouldn't have a problem finding such information. I'm retired now and don't have access to the University library but another source would be the Water Research Foundation, comprised of three groups, water, wastewater and water reuse - in Alexandria, VA USA.

   1 Comment

   1. I think its Municipal Water District of Orange County (MWDOC), in fact.  As far as I am aware they recycle water to just short of drinking standards before pumping it into their aquifer and leaving it there for several years.  Then they pump it up again and treat it for consumption.  This has several benefits - it pressurizes the aquifer to keep seawater out; processes in the aquifer rock help "treat" the water; and lets the public think they are drinking groundwater rather than having to get them used to the idea of recycled water!  :)