Why are desalination plants so expensive? You'd think they'd be lined up and down every coast in the world.
The very many questions-not-worth-their-own-thread question thread XXV
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Why are desalination plants so expensive? You'd think they'd be lined up and down every coast in the world.
Well if this conversation were taking place in a thread dedicated to art discussion and not part of a miscellaneous "catch-all" we might reach a better understanding.
Since the conversation has moved on from art/paintings, I'll just say goodbye for now and see you elsewhere on the board.
Synobun
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Heh, didn't see that.
Question: Is it awkward watching racially charged films (Django Unchained, The Butler) with black people? What about the reverse; if you're black but watching it with a white person?
Borachio
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Traitorfish
The Tighnahulish Kid
Presumably that depends on the white person, the black person, and their relationship.
Traitorfish
The Tighnahulish Kid
Or the film. Not sure I'd be totally comfortable watching The Wind That Shakes the Barley with an Orangeman, y'know?
Heh, you hit my specialty.
The size of those filters (claimed at 15 nm) is greater than the size of most solvated ions (some, like SO4--, may be larger, but something like 88 wt.% of seawater salt is on average sodium and chloride ions). It is, at the moment, very difficult to consistently manufacture molecular sieves smaller than 30 or so nm with traditional phase inversion techniques and probably smaller than 20 nm with other techniques, which is why I'm a bit skeptical of the manufacturer's claim above. But let's give them the benefit of the doubt, because even with a molecular sieve that filtered out salt ions (around 1-1.2 nm) you would not be able to draw water off that bottle.
The energy cost of desalination is pumping--you have to pressurize the liquid above the osmotic pressure of water to pass it through your membrane. The osmotic pressure is proportional to the concentration of everything that resists movement through the membrane (i.e. not water but all the contaminants), and when you do the math for seawater you usually have a minimum applied pressure of somewhere near 25 bar. Actual RO plants usually operate above 50 bar, sometimes as high as 80 bar, for efficiency reasons. Long story short, that kind of equipment as well as doing proper cleaning and antifouling is expensive and it's been easier in the US to use nanofiltration on freshwater and wastewater resources rather than go all-in on RO.
hobbsyoyo
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I have no idea what an Orangeman is, but that's a great (and extremely depressing) movie.
Farm Boy
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Borachio
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Really? You've no idea what an Orangeman is?
(This picture shows their cheery side, btw.)
On second thoughts, I suppose there's no reason why you should know. And your ignorance does you credit, if anything.
I'd like to point out, though, that the Orange Order seriously considered joining in on the Nazi side during WW2 - if the UK government did, or didn't do, something or other; I forget what exactly. (Or maybe that's just a myth.)
(This picture shows their cheery side, btw.)
On second thoughts, I suppose there's no reason why you should know. And your ignorance does you credit, if anything.
I'd like to point out, though, that the Orange Order seriously considered joining in on the Nazi side during WW2 - if the UK government did, or didn't do, something or other; I forget what exactly. (Or maybe that's just a myth.)
Traitorfish
The Tighnahulish Kid
The story, as I understand it, is that Churchill wanted to give de Valera the six counties in exchange for Irish entry into the war, mostly because that would give the Allies unlimited access to Irish ports. (He may also have hoped to keep it in the Commonwealth, because Churchill had big plans for the restructuring the Commonwealth as a sort of British Empire 2.0.) This was never made very public, obviously, but rumours got about, and a lot of Loyalists were quite prepared to stage a pro-Axis insurrection if it went through. Dev turned it down in the end, because he quite rightly suspected that Churchill did not possess the authority to make the offer. (Mad Winston was never one to feel particularly constrained by petty things like constitutional law. Something in common with Roosevelt and Uncle Joe in that respect.)
One of the tricky things about Loyalists is that, while they insist upon their undying loyalty to the British crown and Protestant faith, they've always defined the nature of that loyalty on their own terms. Starting a civil war has never seemed to them incompatible with their proclaimed constitutional loyalties, which is why they threatened to do it in 1914, considered doing it in 1940, and actually did in in 1969.
Also, on "Orangeman", the term does literally mean a member of the Orange Order, but can be more broadly used to refer to chauvinistic Protestants, specifically in Ireland, but also in certain parts of Scotland and England where the Order has an historical presence. "Orange" is also used as a symbol for Irish Protestants or the Ulstermen generally, hence its use in the Irish tricolour. (The tension here hasn't gone unnoticed, and some more chauvinistic Catholics have taken to insisting that it's not orange, it's gold, which symbolises... something.)
(...And I've gone and Ireland-jacked this thread, haven't I? Damn. At least it was a semi-organic jacking.)
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