[michael papworth]

Hi

I use my 110 landrover for mant things as well as window cleaning, just wanted to know if i could safely use the water for drinking making tea cooking and washing save me swapping water over when i go camping & green lanning. at the weekends.

tom

The concensus seems to be that you shouldn't use it for drinking if it's been (i) through the DI unit and (ii) stored in a can for any appreciable time.

Water taken directly from the RO unit is fine for drinking - and is about the same purity as rain water (003) or mountain stream water (020).

[jewelcleaning]

What a wally!

How does 2nd law of thermo dynamics apply here then?  A tendancy towards disorder.

[michael papworth]

What a wally!

How does 2nd law of thermo dynamics apply here then?  A tendancy towards disorder.

Precisely - but don't forget that the law applies to the Universe as a whole. It is possible to create order in one spot in the universe - but at the expense of creating more disorder elsewhere. Thus freezing water causes the molecules to become ordered, but the energy cost of doing that is more disorder in the power station as the fuel to create the electricity is burned.

I don't really think that we need to concern ourselves as it does get complex.

Please just believe me that reverse osmosis doesn't occur in nature and that the person who wrote that article was either ill-educated in science or just plain sloppy in his language.

And the laws of thermodynamics aren't inventions of scientists. They are observations of the way in which the universe works and mathematical descriptions of the workings of the universe. They cannot be broken since the universe would be a different place if they were broken.

And drinking RO water is fine!

[jewelcleaning]

What a wally!

How does 2nd law of thermo dynamics apply here then?  A tendancy towards disorder.

Precisely - but don't forget that the law applies to the Universe as a whole. It is possible to create order in one spot in the universe - but at the expense of creating more disorder elsewhere. Thus freezing water causes the molecules to become ordered, but the energy cost of doing that is more disorder in the power station as the fuel to create the electricity is burned.

I don't really think that we need to concern ourselves as it does get complex.

Please just believe me that reverse osmosis doesn't occur in nature and that the person who wrote that article was either ill-educated in science or just plain sloppy in his language.

And the laws of thermodynamics aren't inventions of scientists. They are observations of the way in which the universe works and mathematical descriptions of the workings of the universe. They cannot be broken since the universe would be a different place if they were broken.

And drinking RO water is fine!

Wally!

Yup.  Ok.

As I said, it's my father in law who's a tree surgeon, not me, and I don't pretend to know all about these things!

Perhaps the term "R/O" regarding tree's etc is just a descriptive term, ie centrifugal force (is not a force!).

I was genuinely interested in how 2nd law of thermo what-nots applied here, that's all.   Not trying to be argumentative!

Anyway, you are obviously a smart guy.  I just wonder.. with all your knowledge about the universe.. would you readily tell me it all came about by chance?

J

[alanwilson]

wally could you tell me where you studied physics?

I studied engineering at University of Edinburgh (more than a few weeks ago I might add), member of the IME, got my doctorate from Kings college, lectured for a year at MIT, worked far too long in aerospace.

Much happier ( and financially better off!) now.

I studied a lot of what you studied (or prob would have studied), thermodynamics, fluid mechanics, statics, pure maths, quantum physics (granted its got a lot more to do with chemistry - which I also studied to a lesser degree but thats a different story).

[michael papworth]

This sounds like a question about the Big Bang Theory.

Is there any hard evidence for it? More than you could shake even a very large stick at. All the scientific evidence points towards a Big Bang.

Is there any truth in it? - Difficult to say with certainly.

[michael papworth]

wally could you tell me where you studied physics?

I studied engineering at University of Edinburgh (more than a few weeks ago I might add), member of the IME, got my doctorate from Kings college, lectured for a year at MIT, worked far too long in aerospace.

Much happier ( and financially better off!) now.

I studied a lot of what you studied (or prob would have studied), thermodynamics, fluid mechanics, statics, pure maths, quantum physics (granted its got a lot more to do with chemistry - which I also studied to a lesser degree but thats a different story).

Wow!!

I got my degree from University of Birmingham. Did all that stuff plus a bit of Phys Metallurgy and a LOT of astophysics. Now that is mind blowing - integrating in 27-dimensional space and lots of non-trivial answers! Wanted to go on to a PhD in Astronomy at CalTech but got sidetracked.

Much happened and now I'm a happy window cleaner.

And - just to stay on-topic - use water from my RO unit to make tea and to drink with meals ... and it's delicious!

[[GQC] Tim]

RO Units are actually used widely in food industry, and to supply drinking water.

[Sanity]

Bleugh...

[chrismroberts]

According to the manual, Merlins are designed originally to produce drinking water? They've just been borrowed by the window cleaning industry for better purposes I guess this means most RO units will be OK?

[tomy jackson]

legenairs de is only in tanks air con wher worme water is in the uk , dusent make you go to loo ,

[elite mike]

Dont drink it if its gone through the DI, you'll end up sh@tting through the eye of a needle. I know, the other year when it was real hot I didnt think it'd matter but jeeezz I was going three or foar times a day and it was brown but as runny as what came out the tank

sorry ,but that is so funny 

[Clive McDonald]

Just read this post. I wondered why jewel cleared off.

I think it's not a physics, but an English Language question. As users of reverse osmosis systems we use the phrase as a name or a noun which describes what the system (including the pump or the pressure from the water company) does. The writer who used the words about tree roots used the words as a descriptive phrase, osmosis working in the opposite direction being to his mind reverse osmosis.

You are very lucky to have someone as pedantic as me on the forum.


Further more, the poor biologist, who you sited as either a non scientist or a user of sloppy language would be incandesant to hear you talk about cell walls, when in fact what you mean is semi permeable membranes.

[alanwilson]

Just read this post. I wondered why jewel cleared off.

Further more, the poor biologist, who you sited as either a non scientist or a user of sloppy language would be incandesant to hear you talk about cell walls, when in fact what you mean is semi permeable membranes.

actually in biology they talk about plant cells having cell walls, they are completely different to animal cells in structure.

not being smart or having a go but I just asked my brother in law who happens to be over visiting (he's a micro-biologist).






I'll shut up now.

[alanwilson]

RO water will hydrate you much faster than tap water, however it won't actually provide you any discenable amount of vitamins and minerals as obviously they have been removed, it is good to drink though as the main function of drinking water is rehydrate and thats what drinking ro water does quite fast.

DI water is not really safe to drink primarily because of the chance that some of the di grains (which are polystyrene) are present in the water - they are toxic and should be avoided. 

Further note DI water is so bland its disgusting.  I've tried it although RO water does make lovely tea etc and is good to drink, rehydrates you very fast - after all that is what the technology was originally intended for when NASA developed ro technology about 30 years ago.

If you do decide to drink ro water remember to flush the membranes regularly, keep the prefilters clean and fit a post-carbon filter, this is a caron filter which goes inline AFTER the ro membranes, it improves the taste of the water and stops bacteria, viruses etc from getting into the water you drink.

[michael papworth]

Where does this idea of RO water leaching minerals from your body come from?

It absolutely will not do this!

For a start, by the time the water has trickled down your throat etc into your stomach it has probably picked up plenty of stuff to make it impure.

And even if it goes into your stomach as pure water, it will mix with the other contents of your stomach and pick up plenty of stuff.

And even if it didn't do that, it would be drawn into your body through osmosis.

Repeat - RO water will NOT draw minerals from your body.

Rainwater, which is perfectly fine for drinking, is typically 003 ppm tds. Water from an RO unit is typically between 009 and 030 ppm tds.

[[GQC] Tim]

If you do decide to drink ro water remember to flush the membranes regularly, keep the prefilters clean and fit a post-carbon filter, this is a caron filter which goes inline AFTER the ro membranes, it improves the taste of the water and stops bacteria, viruses etc from getting into the water you drink.

You don't need one of them after your RO, it's part of the pre filters, they do exactly the same. That's why you have a Carbon block, and Carbon granulated filter, they need to remove that before it goes through the membranes.

RO's are for food industry.

RO water leaching minerals from your body is simply hilarious.

Like people say pure water is aggressive. Pfff, I should have a sign near my shed saying, 'Beware of Pure water'.

[michael papworth]

I don't have any hard evidence that drinking RO water isn't harmful.

I'm basing what I say on the fact that it is simply water with stuff taken out and nothing added. It is similar in chemical composition/purity to rain water or mountain stream water (before the goats have peed into it!).

And I'm saying that drinking the stuff cannot leach minerals from your body because osmosis doesn't work in that direction.

* (there) is no proof that (drinking RO water) is good for you they will take your money whether it’s good or bad for you!

>>> True

* The medical crowd have know for decades that long term drinking of RO has detrimental effects to your health, they say its ok for a few weeks to detoxify your body of poisons.

>>> What medical crowd?

* ...there is evidence now to prove RO water being consumed over a long period does cause damage to your body.

>>> What evidence?

* Coca Cola is made using RO water with all the problems it has caused to peoples health, some of the medical problems they discovered are directly from the RO water not the other Ingredients.

>>> What problems and who discovered them?

I'm really not trying to be difficult here. I genuinely want to know the answers. If you know stuff that I don't, then I respect that and I'd like to know it for myself. The last thing I want to do is to defend my corner if I'm completely wrong!

I love learning new stuff and welcome being put right when I'm wrong about something.

[alanwilson]

If you do decide to drink ro water remember to flush the membranes regularly, keep the prefilters clean and fit a post-carbon filter, this is a caron filter which goes inline AFTER the ro membranes, it improves the taste of the water and stops bacteria, viruses etc from getting into the water you drink.

You don't need one of them after your RO, it's part of the pre filters, they do exactly the same. That's why you have a Carbon block, and Carbon granulated filter, they need to remove that before it goes through the membranes.

RO's are for food industry.

RO water leaching minerals from your body is simply hilarious.

Like people say pure water is aggressive. Pfff, I should have a sign near my shed saying, 'Beware of Pure water'.

If you would read what I'm saying a little bit more carefully you would see I'm not talking about GAC/PAC or indeed carbon block filters, I'm talking about carbon POST filters, they go AFTER the membranes, they have a different function to GAC/PAC/Carbon block filters.

Time and time again people don't bother to read carefully what was posted before.

tell you what go ring june @ gapswater and see what she tells you.  She is an expert in these matters.

[michael papworth]

This info might be useful:

www.waterfiltersonline.com/comparisons.asp