LIKE OIL & WATER?
Posted: Mon Jul 28, 2008 1:50 pm |
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| CBBB |
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| Joined: 20 May 2008 |
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Posted: Mon Jul 28, 2008 2:01 pm |
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| Nikitas |
| professor |

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| Joined: 09 Aug 2007 |
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CBBB,
sometime around 2004 I was commissioned to write a report on the sewater greenhouse. It is a great idea for agriculture rather than straightforward water production. However, the principles it relies on, humidification-dehumidification have been used in desalination with success.
Now think, how is it that a bunch of English technicians, working in London, were able to come up with the Seawatergreenhouse and so many graduate Cypriots working in hot and parched Cyprus have not! It seems we have reversed the idea that necessity is the mother of invention. |
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Posted: Mon Jul 28, 2008 2:19 pm |
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| Nikitas |
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| Joined: 09 Aug 2007 |
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Solar desalination is simple in principle, a little bit complicated in practice because it relies on some clever high tech materials, and is comparatively cheap if you do not require masses of water. The modern setup is different from the simple solar ponds of the 60s.
The system works on two cycles, water and air. Cold seawater is drawn into a heat exchanger chamber were it is used to condense vapours and turn them into fresh water. From there it goes through a solar heater and reaches 60 degrees, then it trickles down through microfiber material in the vaporisation chamber, and from there back to the sea. Air is heated in a solar heater and then passes through the vaporisation chamber where it picks up vapors from the microfiber material, then on to the condensation chamber where the vapors are liquified and then back to the heater to be heated again. All energy for heats and pumps is solar. There are no membranes to clog up, no salt residues in the water produced. The system relies on basic physics. One Dutch group reports that it can produce 1 cubic meter of water from an installation covering one square meter of land. One cubic meter of water can water one thousand lettuces per day, or cover the monthly needs of a small family with zero energy input. |
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Posted: Mon Jul 28, 2008 2:33 pm |
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| CBBB |
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Nikitas,
I agree with your observations regarding the inability of our graduates to come up with something, but think it is probably due to them all wanting Government jobs where they are encouraged to sit on their ass and not use any initiative. |
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Posted: Mon Jul 28, 2008 4:22 pm |
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| Nikitas |
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| Joined: 09 Aug 2007 |
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CBBB,
I know the phenomenon. Had several acquaintances who got agronomy degrees, and while their families had viable properties that could be cultivated profitably, they all sought government or teaching jobs. When I asked them about the paradox they said they did not go study so they would end up working the land like peasants. |
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