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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."
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.