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China Turns to the Sea for Fresh Water

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Re: China Turns to the Sea for Fresh Water

#31

Post by ChuckMcM »

kiba wrote: post #8
lnlyplnt wrote: post #2

Israel (obv a different scale than china) has recently also experienced a big push toward desal. What's interesting is there's a moore's law type of effect at play here, desal keeps getting cheaper and cheaper to the point where it's actually a practical alternative to ground water, filtering etc. I think water will be another great Malthusian disappointment, ocean water is basically unlimited (correct me if I'm mist…

What will you do with the salts and various impurities?

Many desalination plants mix it back into the ocean, you pump more water than you are desalinating and the 'waste water' is a mixed brine at an acceptable salinity level.

That said with global warming melting a bunch of fresh water glaciers into the ocean, one of the side effects is lowering the salinity level. This suggests to me that boosting it slightly by desal efforts will be negligible at worst, and remediation at best.

And of course the quantities we're talking about are pretty much mouse nuts with respect to the entire ocean. But an interesting question to play with is when does a 'keystone pipeline for water' make sense? Clearly Boston would have not minded shipping snow to California to get rid of it this winter. China is working to reroute major water ways, could we manage flood levels on the Mississippi that way? I don't know but it is fun to imagine.

Re: China Turns to the Sea for Fresh Water

#32

Post by dalke »

maxerickson wrote: post #17
dalke wrote: post #7

Earlier quoted context omitted.

If that were reasonable then we would tank water in from Alaska. Or China would buy AK water. If you want to dream big, in the 1980s there were pipe dreams of bringing in water from the Copper or the Stikine through a large off-shore pipeline to California.

There have been serious proposals to ship Great Lakes water to Asia. This article mentions one: http://www.wbez.org/frontandcenter/2011-06-21/great-lakes-fa... There is now an agreement placing tight limits on what happens to the water: http://en.wikipedia.org/wiki/Great_Lakes%E2%80%93Saint_Lawre...

There's serious and then there's serious.

Fiji exports water to the US. I've heard of a bagel company in London which imports its water from New York City. People buy ice that comes from Alaskan glaciers. (Minor note: If you use under 20 tons/year of tidewater glacier ice then you don't need a permit.) So people are willing to pay a lot of money for provenance.

Fiji Water is a good comparison. According to its Wikipedia page, it was exporting over 15 million liters/month. According to others, it was a least 3.5 million liters per month. According to http://www.alternet.org/story/101207/the_true_price_of_fiji_... it was 130 million liters in a year. I'll say it was 5 million L/month or 60 million L/year.

According to the Wikipedia page for "Water export", the Great Lakes -> Asia deal was for 600 million liters, or about 10x of what a single well in Fiji can provide.

Oil shipping costs something like $1.20/barrel from Qatar to Rotterdam, says https://books.google.com/books?id=cUHAAgAAQBAJ&pg=PA232&lpg=... . A barrel is 120 liters, or 1 cent per liter shipping costs.

That's about $12 thousand per acre-foot. The price of desal water is under $3,000 an acre-foot.

If the goal was to market provenance - the Fiji Water of Asia - then it might be profitable. It otherwise doesn't seem like a serious proposal.

If there were a were serious need, then I would expect to see water exports from Alaska, which allows bulk water exports (again, according to the "Water export" page at Wikipedia) and is a lot closer to Asia.

Since there isn't, I have difficulties understanding how there's a serious proposal.

Re: China Turns to the Sea for Fresh Water

#33

Post by maxerickson »

dalke wrote: post #32
maxerickson wrote: post #17

Earlier quoted context omitted.

There have been serious proposals to ship Great Lakes water to Asia. This article mentions one: http://www.wbez.org/frontandcenter/2011-06-21/great-lakes-fa... There is now an agreement placing tight limits on what happens to the water: http://en.wikipedia.org/wiki/Great_Lakes%E2%80%93Saint_Lawre...

There's serious and then there's serious. Fiji exports water to the US. I've heard of a bagel company in London which imports its water from New York City. People buy ice that comes from Alaskan glaciers. (Minor note: If you use under 20 tons/year of tidewater glacier ice then you don't need a permit.) So people are willing to pay a lot of money for provenance. Fiji Water is a good comparison. According to its Wikipe…

There certainly isn't a serious existing proposal, there is a series of agreements making sure it isn't done.

I was just saying that someone had thought about doing it, enough so that they went ahead and got a permit.

I wonder what the prices for shipping and desal were in 1997...

Re: China Turns to the Sea for Fresh Water

#34

Post by mmoche »

hyperbovine wrote: post #27
mmoche wrote: post #6

Earlier quoted context omitted.

Agreed. Particularly for California which has heavy energy and water needs, nuclear desalination seems like the most future-proof approach, particularly considering the dramatic decrease in aquifer volume as groundwater is extracted to make up for drought-level rainfall.

This seems to be a common fallacy: desal, which is being considered by a few wealthy urban water districts on the coast, will do absolutely nothing to alleviate overpumping by farmers in the Central Valley.

I think the goal would be to scale desalination efforts to the point where it can replace groundwater pumping statewide. This would come at a huge cost, sure, but once the groundwater runs out, the economics won't look so bad.

Re: China Turns to the Sea for Fresh Water

#35

Post by Someone »

"the facility will remove salt from 120,000 tons of seawater each day. The result will be 50,000 tons of potable water"

Huh? What happens to the other 70,000 tons of water? Or do they mean it will take in 120,000 tons, use something (e.g. distillation, filtering) to move almost all the salt in it to about half of it, and get 50,000 tons of potable water and 70,000 tons of about twice as salty as the input water?

Re: China Turns to the Sea for Fresh Water

#36

Post by adinb »

How crazy would it be to (Mostly to help the American Southwest, though if it worked, it could be used anywhere that uses river basins as a major source of freshwater for extremely large areas) create a large pipeline to feed an inland desal plant that's located along the shortest, lowest, least populated path to the headwaters of multiple major freshwater sources, like the Colorado and Rio Grande and the pump desal water into the existing water distribution network?

While it's a major geoengineering project (musk-scale!), it would allow for usage of current legal and physical water distribution to be reused.

Also, while CA desal cites briny outflow disposal as a major impediment to desal, why not pump the outflow to existing salt flats?

(Edited for clarity)

Re: China Turns to the Sea for Fresh Water

#37

Post by ars »

banachtarski wrote: post #14
IkmoIkmo wrote: post #13

Earlier quoted context omitted.

Considering drinking water is some tiny, tiny fraction of the world's water, it's probably not going to be a crazy idea to just dump the salt etc back in the oceans where it came from without causing any crazy imbalance, because we're talking about less than 1% of water. About 2.5% of all the world's water is fresh water, and of that about 65% is in glaciers and icecaps. The roughly 0.8% of the world's water that rem…

This is emphatically not true. The salinated impurities that are a byproduct of this process will kill everything in the zone that is is reintroduced to. Just because it is a small fraction of the ocean doesn't mean we can easily spread it across the entire ocean. Even then, we are doing an irreversible transformation of the ocean as a whole, and we need to be smart about the waste for the process to be sustainable.…

> The salinated impurities that are a byproduct of this process

That's a very inaccurate way of saying that. You are implying that that desalination creates new byproducts. It does not. Any byproducts were already in the ocean.

You just run your outflow pipe far into the ocean, and mix it with ordinary seawater and it's sufficiently diluted.

Re: China Turns to the Sea for Fresh Water

#38

Post by thomabs »

Desalination uses TONS of electricity. Where does that electricity come from? Fossil fuels. So this "solution" to water shortage actually increases global warming, which will worsen water shortages. And what happens with all the extracted salt? You guessed it - it goes right back, increasing the salinity of the oceans.

Ah, humans.

But hey, technology solves all problems, right YC?

Re: China Turns to the Sea for Fresh Water

#39

Post by minthd »

lnlyplnt wrote: post #2

Israel (obv a different scale than china) has recently also experienced a big push toward desal. What's interesting is there's a moore's law type of effect at play here, desal keeps getting cheaper and cheaper to the point where it's actually a practical alternative to ground water, filtering etc. I think water will be another great Malthusian disappointment, ocean water is basically unlimited (correct me if I'm mist…

Looking at price trends of desalination and solar power leads to the conclusion that by 2050, the 100km coastal region everywhere could have access to affordable water, and by 2040 in the western world[1].

Personally i think that water consumption will greatly decrease in the future, because of the great water saving potential of synthetic biology as a way for growing food:

In theory using synthetic biology and making basic food components[amino acids, fats, flavourants, etc] can make all the food the world eat, at a land size of rhode island with something like 1/1000 less water than today, generating around 1% of greenhouses gases , and at something between 5-20 cents/pound.And molecular gastronomy and food science know, or are rapidly learning,how to make it into tasty food.

As an example for that, there's a company(prottero) that uses synthetic biology, and already making sugar at 5 cents/pound - 1/2-1/3 of the cost of regular sugar, with 30x the land efficiency.

So yes, i think Malthusians will be very disappointed.

[1]http://www.syngentafoundation.org/db/1/1299.pdf

Re: China Turns to the Sea for Fresh Water

#40

Post by infinotize »

ars wrote: post #37
banachtarski wrote: post #14

Earlier quoted context omitted.

This is emphatically not true. The salinated impurities that are a byproduct of this process will kill everything in the zone that is is reintroduced to. Just because it is a small fraction of the ocean doesn't mean we can easily spread it across the entire ocean. Even then, we are doing an irreversible transformation of the ocean as a whole, and we need to be smart about the waste for the process to be sustainable.…

> The salinated impurities that are a byproduct of this process That's a very inaccurate way of saying that. You are implying that that desalination creates new byproducts. It does not. Any byproducts were already in the ocean. You just run your outflow pipe far into the ocean, and mix it with ordinary seawater and it's sufficiently diluted.

That's misleading. It's not technically a byproduct, but taking literally tons of salt that was spread evenly throughout the ocean and dumping it out at high concentration at the end of a pipe has significant (and bad) ramifications for the ecosystem at the end of the pipe.
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