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Desalination Plant Begins Operation in Tampa
ambisinistral writes "The Tampa Tribune reports that the first commercial desalination plant in the U.S. is set to begin operations today. By March the plant is expected to be operating at full capacity, producing 25 million gallons of fresh water a day (10% of the water currently provided to the area from well fields).
There are ecological concerns about returning highly saline water from the plant back into Tampa Bay. Proponents of desalination claim the natural tide cycle will effectively flush the bay of the saline rich discharge, while opponents of the plant feel the ecology of the bay will be badly damaged. Both sides plan on strict monitoring of the situation."
To raise vast quantities of sea monkeys in Tampa Bay.
"Eve of Destruction", it's not just for old hippies anymore...
Dr. Flammond:
"A year ago, I was close to perfecting the first magnetic desalinization process. So revolutionary, it was capable of removing the salt of over 500 million gallons of sea water a day. Do you realize what that could mean to the starving nations of the earth."
Nick:
"Wow, they would have enough salt to last them forever."
Top Secret!
We in the US take water for granted. It's basically free -- cheaper than all other utilities, our water bill is about $15 a month, tops.
Not only do we take it for granted, we tend to take it at the expense of the environment or others downstream. The Colorado River, for example, is only a trickle of a dried-up stream where it used to dump into the ocean, and many Mexican communities have been lost, all because people keep moving to LA and, well, needing water.
We need to be much more aware of how we use water in this country, and most importantly, start looking for alternative sources whenever local demands start to affect the ecology or overall flow levels of major rivers.
Desalinization is a great step -- but the next big step would be builidng the huge pipelines (or canals, which'd be much cheaper) to bring water from the coasts to interior cities (though, since most of the population, and thus, most of the worst of the water problems, are near the coast, this isn't as bad as it might be). (yes, I'm ignoring cyclical dust-bowl problems or interior water-starved cities like San Antonio).
Of course, if this current effort flops, then it'll be much tougher to get other cities interested in the program.
It'd be, obviously, preferable of they could use some kind of distillation system, rather than permeable membranes, to arrive at "pure" water with disposable solids (that might themselves be mineable for things like table salt or other chemicals). On the other hand, it might be possible to pipe the very salty "leftover" water back into the ocean, but through a wide-ranging diffusion network over several hundred square miles.
At any rate, I really hope this works!
Why the heck are they dumping it? Why not sell the salt? Around here, salt is generally obtained in much the same way it has been obtained for thousands of years, by letting sea water evaporate. The only reason I can come up with for them not to sell the salt is that said water is heavily polluted and maybe it would be hard to clean??
Since the feds have strictly curtailed California's ability to take water from the Colorado River, California needs to build desalination plants like this one, and to do it quickly! Too bad they will take 10 or 20 years debating it.
How ya like dat?
On Curacao, an island in the Caribbean Sea, we desalinate our drinking water since 1928. We call it the 'World's Best Water' (and probably most expensive as well! my past month's waterbill was approx. US$ 120.-).
But what the brine does with our coral reef? I dunno, but ppl who are interested in finding out might get some answers from the ppl of NACRI, the Netherlands Antilles Coral Reef Initiative.
"We'll reach that bridge when we find it" - Suzy Romer, prime minister Netherlands Antilles '98-'99
I believe that both the proponents of the project, as well as the ecology-defenders, have valid points.
But, just remember to take everything with a grain of salt...
The dumber people think you are, the more surprised they are when you kill them.
dilute the salty water
Use water that is going into the bay anyway like form wast water treatment to dilute the salty water. This might be difficult if the wast water plant is far from the desalination plant. This of course makes one wonder if it would not be better to treat the wast water back to a potable form. Though I suspect there is a social factor in why people don't like this idea.
--we use solar PV here, and have three battery banks. Needing a lot of distilled water every month, we got a commercial solar distiller, which is mounted down by the panel arrays. It's roughly a 3 foot by 5 foot box with a glass top that is sealed to the sides. It worked pretty good for around a year,2-3 gallons a day output, then it stopped working, the glass developed some recurring film that stops the drips from falling into the collection tray. We tried adjusting the angle, etc, opened it up, cleaned the glass several times-nada. It evaporates water great,that part works as advertised, then the water that collects on the glass just sits there until the weight of the droplet causes it to fall right back into the pool of water, instead of sliding down the incline. So we switched to an electric distiller for now, next summer I'm going to make a hot water heater out of the thing and design and build my own distiller. The glass cleaning deal really stumped us, we tried vinegar, windex, you name it, that glass is spotless clean, but within a day or two it gets dirty enough to stop working-just unacceptable. There's probably some sort of application chemical like rain-x or something to use but it's a hassle to keep doing that, it should "just work" for at least a month without having to open it up for additional cleaning. I imagine on a bigger scale it would actually work better as you could have extremely steep sides for the collection efforts.
There's a neat deal that was invented, it uses rotating sails to collect moisture from the air, some places in south america are using it now. this was covered on slashdot before earlier this summer, here's a generic link to a page of links about fog collection. cool stuff.
While most vertebrates have mechanisms to rid themselves of excess salt most invertebrates (sessile or otherwise) do NOT have such mechanisms and depend on their environment to maintain a constant salt concentration. (Note: I have been building salt water aquariums for decades). Suffice to say increasing the salt content even slightly will more them likely not effect fish and up, but will at best stress most invertebrates making them susceptible to disease and at worst kill off large numbers of them and most certainly damage any coral. In turn this could damage food supplies, breeding areas etc for other animals not effected by the increase in salt.
You might decide that this is looney because Lyndon LaRouche is associated with it.
...
You have to understand first that LaRouche is NOT a Libertarian - he is a Democrat. That in itself, explains much.
Anyhow
Outline of NAWAPA
"The North American Water and Power Alliance--NAWAPA--is the most comprehensive of a series of plans developed during the 1950s and 1960s to capture and redistribute fresh water in Alaska and Canada. NAWAPA would deliver large quantities of water to water-poor areas of Canada, the lower forty-eight states of the United States of America, and Mexico."
and the map of the project.
Liberty is not a concept... Liberty is a way of life!!!
As opposed to the crap they dump into the bay every time it rains hard?
There is going to be a water shortage in the future, and I believe that there is a very easy way to deal with it, however it will require a change in thinking, and an investment in infrastructure:
I don't know how many of you drink the tap water in your community, but here in Canada I know of few people that don't. But we also water our lawns with it, bathe in it, wash dishes with it, wash our cars with it, water our plants with it, etc. etc. etc.
Do you see a pattern here? We use drinkable/potable water for a huge number of things that don't require the water to be drinkable. We spend huge amounts of money to treat our water to then pour it onto our lawns and cars? This makes no sense. What we need is a dual system of delivery: the taps in your kitchen provide drinking water, but the faucet in your laundry room or on the exterior of your house provide non-drinking water for general use.
We could then forgo a huge number of costly, time-consuming treatments for water that is simply not meant for consumption. Previously non-viable sources of water suddenly become available for use in the "secondary" system of water.
You surely don't care if the water that is cleaning your clothing is chlorinated and fluorinated, do you?
I used to work for a research institute that monitored tidal conditions along the Texas coast. One thing we did was monitor salinity and dissolved oxygen levels in the Corpus Christi and Nueces bays. It wasn't from desal plants, but from the Nueces river being dammed in, limiting it's flow into the bays. This caused salinity to rise, and dissolved oxygen to decrease, putting the local wildlife in danger. They used our measurements to schedule releases--times when they would open the dams and dump X amount of fresh water into the bay in order to correct the levels. As far as I know, it worked just like it was supposed to.
I haven't looked up any maps of the area, but surely there are similar factors at play.
Your last point is the key to how very efficient distillation systems work.
You put the heat into the water to make the vapor.
Then you take the heat back out of the vapor to get pure water.
Using the heat from step 2 in step 1 is how you get high efficiency.
Since the two temperatures need only be on either side of the dew point, you can run the system at any average temperature you like. Instead of heating the water to make vapor, you can cool the vapor to make water.
One scheme pumped cold water from low ocean depths to chill air below the dew point. Pumping water is cheap compared to raising the temperature.
As for worrying about high salinity, that need not be a problem. You need only remove enough water that the salinity changes by one or two percent (i.e. from 0.0035 to 0.0036). The seawater can be continuously pumped through the system, with only a small amount of water removed at any one time.
Free book: Science Toys You Can Make
Proponents hyped both as solutions to the crisis, even though the CWP never delivers to full capacity when it is most needed (during a drought), is much more expensive than was originally stated, and the desalination plant was never used yet must still be maintained yearly.
In fact, the largest proponents of the addition of state water and the desal. plant were developers, who saw a way around the county's long-standing moratorium on new water hookups (the county essentially running Mulholland's famous "whoever brings the water brings the people" in reverse to keep development at bay).
In general, Marc Reisner's "Cadillac Desert" is a good review for those interested in the politics of water in the West. The issues faced by the semi-arid West are starting to appear elsewhere in the U.S. as our population grows, and we would do well to learn the lessons of the past.
Can't you see that everyone is buying station wagons?
---
I thought that was just a problem with the morons running the government in Milwaukee
"I can't give you a brain, so I'll give you a diploma" - The Great Oz (blatently stolen sig)
---hmm, didn't think of buffing it, thanks for the tip! It's a pain to get to the inside glass, it's permanently glued down with caulk, have to cut it off then re apply the caulk each time-another lame design feature. The good thing is I didn't buy it, the folks I work for did. If I don't make a solar water heater out of the box, I might try building a door for the glass on a hinge with some sort of permanent gasket, then try some more cleaning techniques, including the buffing. We washed it carefully before, used paper towels, crumpled newspaper, and lint free cloth, truly annoying to not have it "work" again after those efforts. Seems like the vinegar should have removed the calcium/mineral deposits though, but it obviously didn't. It's a perfectly good theory, actually evaporates the water quickly once the sun starts hitting it, just the collection part is dismal. Anyway, it's winter now, wouldn't work all that good when it's so cold out, next spring I'l mess with it again. I *might* try exhausting the moisture laden air and just using a huge coil of hose as the cooling mechanism leading to the collection container, then not worry about collecting it inside the box. Tipping it slightly so that a normal thermosiphon effect would come into play would probably work, ie, "heat doth rise".
Had to refill one bank of batts yesterday, it wasn't too bad, 24 T-105 Trojan 6 volters took around 6 gallons to top them off to the correct levels. I had a large food grade plastic drum I was trying to fill up before winter with the solar distilled water, that was "the plan" anyway, too bad I have to waste juice now to make the water. Oh well...
There was a desalination plant off the coast of Freeport, Texas for about a decade during the '60s and '70s.
I think it was a pilot project, so the article can still claim "first commercial desalination plant" in the USA.
Sheesh, evil *and* a jerk. -- Jade
Maybe Beck Hansen could give a promo concert for the opening of the plant. There is always Erika Christensen. Nice boobs, but that is one screwed up girl. Maybe Lisa Marie could put a collection of Elvis hits for the occasion.
Clearwater is Scientology Central.
Spot a thetan.
--a synthetic thread that didn't absorb water might work like that, but the problem would be you'd need so many of them attached (glued?) to the upper glass collection plate that they would block the sunlight infra rad heat from hitting the water to be distilled in the bottom of the solar collection box. You want as much "open" space as possible so the heat gets transferred to the water so it will evaporate. Catch 22 then. When the distiller is operating, as the water heats up from the hot sun hitting it, first you get a 'fog" on the inside of the glass, just like on your windshield in cold weather. Next you can see the individual droplets getting bigger and bigger, until the weight of the single drops overcomes the surface tension/adhesion on the glass, and the slight angle of the glass allows the drops to "break free" and flow downhill until they come up against a stop and then drip straight down into the collection trough, which is itself at a sight angle to where it exits the box into a short collection tube going to whatever container you have. That's the simple design and it worked well until that dang "too sticky" problem started getting bad. It worked really, really well the first year too, automatic, low tech, lotsa distilled water from some pretty hard well water.
Thanks for the input, yourself and the other poster, helps to have different ideas thrown at problems sometimes, I got some more to think about now. One would be a variation on the threads idea, not for the delivery but for the propogation of liquid water into "humidity", something that would keep the same size box I have but increase the surface area of the water so it evaporated faster at a lower temp. A mass "wicking" action on the bottom of the box itself, some sort of fibrous spongy mat perhaps. Hmmmm and hmmmmm Between that and an external coil condenser it could up the output without having to deal with the "sticky glass" syndrome. hmmmm
I find it odd that they refer to this is the first. I could easily be wrong. But I thought Cape Coral, FL (a 2.5 hr south of tampa, 1.5 hr when I am driving) had a large reverse osmosis desalination plant. The second link even refers to how this is the more power efficient method. I'm pretty sure this place was in operation, since I remember several years back there was talk of taking a field trip from my high school to see it. We also mentioned how it differed from the system of wells that we used (in Fort Myers, the town across the river from Cape Coral)
The real solution to water problems in the American West is not to increase the supply but to make the users pay the real price for the existing supply. This is especially true of farmers, who get water much cheaper than cities do.
I bragged about my Karma at a job interview but I didn't get the job.