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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."
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 $15 a month, tops.
Not only do we take it for granted, we tend to take it at the expense of the environment or others downstream. The Colorado River, for example, is only a trickle of a dried-up stream where it used to dump into the ocean, and many Mexican communities have been lost, all because people keep moving to LA and, well, needing water.
We need to be much more aware of how we use water in this country, and most importantly, start looking for alternative sources whenever local demands start to affect the ecology or overall flow levels of major rivers.
Desalinization is a great step -- but the next big step would be builidng the huge pipelines (or canals, which'd be much cheaper) to bring water from the coasts to interior cities (though, since most of the population, and thus, most of the worst of the water problems, are near the coast, this isn't as bad as it might be). (yes, I'm ignoring cyclical dust-bowl problems or interior water-starved cities like San Antonio).
Of course, if this current effort flops, then it'll be much tougher to get other cities interested in the program.
It'd be, obviously, preferable of they could use some kind of distillation system, rather than permeable membranes, to arrive at "pure" water with disposable solids (that might themselves be mineable for things like table salt or other chemicals). On the other hand, it might be possible to pipe the very salty "leftover" water back into the ocean, but through a wide-ranging diffusion network over several hundred square miles.
At any rate, I really hope this works!
On Curacao, an island in the Caribbean Sea, we desalinate our drinking water since 1928. We call it the 'World's Best Water' (and probably most expensive as well! my past month's waterbill was approx. US$ 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.
Evaporating the brine might be cost efective if the city of Tampa has an in-house use for the salt. If they were located in the snow belt, for example, it might be used for snow/ice removal.
--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.