Talk:Reverse osmosis
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San Diego does not currently recycle waste water back to tap water. I removed the erroneous entry about this. It has been proposed, but was rejected several years ago. The city has conducted a recent study, and the proposal is up for review by a city council committee. Mayor Jerry Sanders opposes the proposal. I find the Los Angeles statement highly suspect in light of this, but I'll leave it to a Los Angeles resident to research. News article: [1]
Dennis Chancelor did not "invent the Reverse osmosis processor" so I removed the reference. This was a very suspect statement supported only by a local newspaper interview with the supposed inventor. A US patent database search show no US patents with an inventor named Chancelor, while in contrast there are 461 US patents with "reverse osmosis system" in the claims section. These go back to 1976. Further - his name shows up nowhere in the scientific literature. I personally was building RO systems in 1970, I worked on developing the technology and several dozen products, systems and applications, from 1970 to 2005, and never heard of this person. Several of the RO commercial founders (Don Bray, Dean Spatz, J. Riley) and the early academics (S, Sourirajan, Merten, Lonsdale etc) are a few of the dozen or so people who could make some type of claim like this - although they would not because once Sourirajan invented it and GulfAtomic corporation developed it under early federal grants, R0 technology was developed in a very widespread and colloborative manner. 65.29.7.173 21:08, 6 July 2006 (UTC)David Paulson65.29.7.173 21:08, 6 July 2006 (UTC)
I am not a biologist, can anyone give a good description of what Reverse Osmosis is on the top of the article? it also needs to be wikified.. -- Rotem Dan 10:40 Apr 14, 2003 (UTC)
- I think we are all looking at this page through the random page lottery. But that will not stop me from mentioning than I am unaware what "osmoisis" is "osmosis" I do know.
- The article is informative, but not to the point. Cimon avaro 10:53 Apr 14, 2003 (UTC)
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- Reverse osmosis (stub which is linked by Osmosis) and the misspelled Reverse osmoisis should be merged, this also should be checked for copyright violation (I will google it..) Rotem Dan 17:41 Apr 14, 2003 (UTC)
Osmosis ...reverse osmosis comes from the process of osmosis, the natural movement of solvent from an area..., in my understanding, is imprecise. Osmosis is the movement of water only not just any solvent - anything else is diffusion. 208.114.132.151 02:16, 22 August 2006 (UTC)
This is a copyright violation, I am blanking this article. see [2] Rotem Dan 17:46 Apr 14, 2003 (UTC)
- Umm, I wrote this stub off the top of my head. These are my own words, and anyone else has used the same words it's probably coincidence. Mkweise 04:27 Apr 17, 2003 (UTC)
Contents |
[edit] Wet Oxidation section is irrelevant
and needs to be removed. This article is about reverse osmosis, not water purification. Unless someone objects, I'd like to move wet oxidation to it's own article. Johnathlon 01:10, 28 July 2005 (UTC)
[edit] unanswered issues
While I'm not qualified to add the info, I'd like to see a little bit more detail regarding the efficiency of RO systems and the water costs involved (my understanding is that RO uses a large quantity of source water to 'produce' a small qty of clean water).
[edit] Drinking Water Purification
i find the latter half of the section, the part with all the citation needed marks, irrelevant to the article. I suggest it either be placed under its own article (Reverse Osmosis and it's effects??) or deleted completely. My motion's on the latter.--Psydude 16:07, 2 June 2006 (UTC)
are you kidding?!!! the only thing you can really apply reverse osmosis to in the REAL WORLD is desolination and water purification, take it from a wastewater treatment civil engineer, leave those sections IN!
[edit] Removed some criticism
Removed:
- RO water used for drinking, generally has a post carbon filter for taste. RO water has a flat taste that most do not like.[citation needed] Therefore the post carbon filter, (usually walnut shells or coconut shell) gives the RO water back its 'normal' flavour.
This is not true - activated carbon does not "give back normal flavor" and it is usually washed and otherwise purified to avoid adding any extracttables. Water "tastes flat" once purified due to the same osmotic effect described earlier - an interaction with the fluid in the cells- taste bud cells in this case. small amounts of salts are added back to improve taste - an example ois Dasani bottled water. 65.29.7.173 15:32, 4 July 2006 (UTC)David Paulson65.29.7.173 15:32, 4 July 2006 (UTC)
- Reverse Osmosis is generally 'oversold' as a system. In other words it is NOT as effective in removing contaminants as people are led to believe[citation needed]. It does not remove all contaminants nor does it remove all bacteria. Without pre-treatment for example it does not remove both forms of arsenic. Reverse Osmosis consists of one membrane in a multi-stage treatment process. It should be used only in situations where no other treatment options exist, such as with high salinity or high total dissolved solids. RO water will be acidic and 'aggressive'[citation needed]. Thus it is NOT optimum from a human health perspective.
This sounds like the addition of somebody with an axe to grind. Even if it's reinserted once citations are supplied, it will need considerable work for neutrality. --Robert Merkel 04:19, 2 July 2006 (UTC)
[edit] Gravity powered reverse osmosis?
"Portable reverse osmosis (RO) water processors are sold for personal water purification in the home. These units are gravity powered (they need no water pump), and need no electricity"
I'm not aware of any gravity powered reverse osmosis system, especially not sold for home use. It's my understanding that a significant pressure is required, more than gravity could supply. I think whoever put this in was confused because most under-sink reverse osmosis systems require no pump or electricity, because there is already enough pressure in the municipal water supply. That is very different than gravity powered, which would be something like a Brita pitcher. If portable, gravity powered reverse osmosis systems were possible, I'm pretty sure they would be sold to the outdoor and marine survival markets. Currently, the desalinator included on some high end life rafts and on some boats is a hand powered device that produces about a liter an hour, with a lot of effort. --24.24.80.35 13:25, 16 July 2006 (UTC)
[edit] external links
I removed the CAI Technologies link as the 'how to choose a system' link. If people want to add suppliers as external links I think that's fine, but identify them as such. CAI is not independent any more than Watts Premier is.208.114.132.151 01:12, 22 August 2006 (UTC)
[edit] Difference from filtration?
Until I read the entry, I was sure that RO was just a marketing term for filtration. It sounds better to say that the water is RO vs. just filtered. Does filtration not apply to removal of solute? Is RO a subset, superset, or alternative compared to filtration? Thanks!
[edit] RO models and structure
It's interesting that much credit (well-deserved) is given to Loeb and Sourirajan, and yet the page states that RO membranes have no pores, a point I suspect they would disagree with given Sourirajan's development and furtherance of membrane pore models such as the Preferential Sorption-Capillary Flow Model. Perhaps this statement could be replaced with a statement such as:
The membranes used for reverse osmosis have a dense polymer barrier layer in which separaton takes place (current theory indicates transport is by diffusion through the barrier layer, known as the solution-diffusion, or through preferrential sorption pore or channel flow). —The preceding unsigned comment was added by 66.83.180.10 (talk) 20:04, 5 December 2006 (UTC).
[edit] reverse osmosis to reduce hardness of d.m water
can the process of reverse osmosis helps to reduce the hardness or Chloride contents of D.M water for Boiler ? also whether it is useful if the intake water is highly contaminated by high sewage mix-up ? what will be the impact on processing cost compared to normal water treatment? —The preceding unsigned comment was added by Anilbapatnasik (talk • contribs) 09:16, 16 February 2007 (UTC).
