reverse osmosis water fountains should be provided at airports

[hejhej]

They make you ditch any water and your only option is to buy bottled water that one creates more plastic waste and two means you have to buy vastly over priced water. Gets my goat. Family of four that's often 10-18 pounds extra.

[maxxytoe]

am I meant to know what reverse osmosis is ?
Where did you learn these things ?

[GGabcd]

Drink beer.

[cardibach]

What's Portugal got to do with it? Safe water there!

[OttiliaVonBCup]

I do agree with op's point about plastic bottle being bad fir the environment.
She did lose me with the chilled reverse osmosis nonsense though.

[londonrach]

I always carry an empty bottle and fill after security. Never know an airport not to have a water fountain. Ask someone op next time you fly

[BigMichaelOctopus]

Few things piss me off more than not being able to take water through security. I have a medical condition to do with my oesophagus which means I have to have water with me at all times. I get chronic heartburn and spasms which come on very suddenly and the only way to stop the severe pain is by drinking ( pain is way, way beyond pain of childbirth). Can't wait to get through security and find a drinking fountain / shop if I get an attack and pain gets worse and worse, longer I leave it, the longer it takes to stop it. I now have a doctor's letter (from NHS) saying I need to keep water with me all the time which has worked all round the world except UK where they insist on taking it off me. Cunts

[woowoo22]

Trains have water. I think. Do they? Who am I? Why are we here...?

[chemenger]

I know what reverse osmosis is!!! Normally you use a semi-permeable membrane a thin sheet of material with very small holes in it which allow water molecules to pass though but not salts, dirt, bacteria etc. If you have clean water on one side and dirty water on the other then normal osmosis means that water goes from the clean side to the dirty side. It does this because nature usually wants to even things out, so it wants to dilute the dirty water to make it more like the clean water.
In reverse osmosis you want the water to go in the opposite direction, from the dirty side to the clean side. This is going against nature (or as we call it in chemical engineering, thermodynamics) so you need to supply energy. The energy is supplied by increasing the pressure on the dirty side until the natural tendency for the water to go from clean to dirty is overcome. As the dirty side gets more concentrated you need higher pressures, so usually you can only transfer a small proportion of the water because the pressure is limited. Well done if you read this far!

[HMSmostleaky]

OP, buy a portable RO and hand pump and carry that in your carry on instead of a book, electronics, duty free or whatever you usually bring.

[Salmotrutta]

So applying that high pressure must require energy then chemenger - and therefore I'm assuming less than ecologically friendly?

Or is the pressure applied by gravity?

[ghostyslovesheep]

chemenger thank you :D you are the only person here who actually understands what it is I suspect

[Pipbin]

Thank you for explaining RO.

Big. I thought all countries require you to get rid of bottled water before flying.

[chemenger]

Gravity would be enough if you have enough of it, you need a tall column of water to give pressure (like the pressure when you dive in the sea). Usually the pressure comes from a pump, so electricity. (The tall column of water doesn't help, really because you need to pump the water to the top of it.) I can feel a student case study coming on here!

[WhoKnowsWhereTheTimeGoes]

I understand, we use RO system in the labs at work to create clean water for experiments, but for drinking I'm more than happy with tap water.

[chemenger]

I don't think it was meant to be patronising, and I'm sure I'm not the only person who understands RO. I think those of us with some technical knowledge forget how alien our world is to much of the population (now I may be being patronising, sorry). I am just the only poster who is compelled to explain things because I don't often get to apply chemical engineering in mumsnet.

[HMSmostleaky]

I know what it is because a number of my friends have them in their houses.

[SoupDragon]

you are the only person here who actually understands what it is I suspect

That's a bit patronising. I suspect there's quite a few scientifically qualified people on here. I know exactly what it is. I just think it might be slightly OTT for a water fountain.

It's not patronising. Whilst she may not be the only person who knows, she's the only one who could be arsed to explain.

[chippednailvarnish]

Could you not just take a cup and drink your own piss? That would be free and no plastic involved?

[SoupDragon]

Well, given no one else could be arsed to answer the multiple questions about what it was, it's not surprising that poster was thought to be the only one who understood.

[futforbaby]

You might wait a long while. And it's prob for security and legal reasons why airports don't or restaurants want to do this. Your better of just getting a bottle with a "lifestraw" filter in it. If you don't know about lifestraw Google it, it's brilliant.