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To: blam
A traditional windmill which drives a pump…In this case, it involves a high-pressure pump which pushes water through a membrane using approximately 60 bar. This reverse osmosis membrane produces fresh water from seawater directly.

It is a nice idea but fraught with problems that the author neglects to mention.

Let’s start with the High Pressure Pump. 60 bar (about 870 psi) not really high pressure but high enough. These pumps can be well built but still will need maintenance. A village that does not have electricity is not likely to have the necessary skilled personnel or tools to perform maintenance on a complex multistage high pressure pump.

Next the Reverse Osmosis unit. The article says that the unit can Provide Fresh Water From Seawater Directly while this is true it is a simplification. In reality to work efficiently and reliably long term the unit will have to have a fairly sizable settling pond to draw sea water from or a backwashable filter to remove suspended solids before passing the water through the RO) unit. Fine suspended solids will clog the membranes and if permitted to remain in the RO membranes permanently damage them.
The RO membrane also needs to be periodically backwashed to remove bacteria and fine suspended solids. The membranes also need to be flushed periodically with proprietary chemicals to remove minerals from the membrane’s pores.
More technical maintenance that a village wit out electricity is not likely to be equipped to perform.

A simple windmill one would think should not be a problem for a reasonably intelligent person with some mechanical aptitude. But this regardless of what the author says is not your typical windmill pump water from a well to a watering trough.
This is a windmill attached to a high pressure pump. In order to drive this pump the in between the windmill and the pump there must be a gear box to change torque (a torque converter) in to the necessary revolutions per minute to generate the required pressure. This torque converter must be able to regulate the number of revolutions per minute to what is required to produce the required pressure. To much seed and to much pressure is produced and the RO membrane is damaged. To little pressure and little fresh water is produced.
This high tech device is the lynch pin of the whole system it will need maintenance and will be the most complex of the mechanical equipment.

Lastly keeping fresh water safe to drink is not a simple task. In the US people responsible for potable water plants must pass test and are licensed. Water can not be stored for long periods as the article suggest. A water reservoir mentioned by the article usually means one open to the sky, available to water fowl and other creatures likely to defecate in the water. A better solution is a cistern below ground and covered. But even a cistern requires that the water be turned over (water cycled in and out) and periodically cleaned.

All of the above means that to make use of even this type of technology requires trained knowledgeable personnel with the appropriate skills and tools to manage the system. Things that you are not likely to find where this article suggest that they intend to place this technology.

I believe the system that they have designed can produce water of excellent quality. But without the people trained to maintain and operate it will not work properly for long.

15 posted on 03/03/2008 7:35:18 PM PST by Pontiac (Your message here.)
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To: Pontiac

Rural Aussies have already solved the water tank problem. Pollie tanks as the Aussies say, or polyethylene tanks. There are more brands of water tanks than you can poke a stick at- Nylex (ARI) Plastank and Nylex Pura Tank, Bushman, Clarks, Aquasource, Rainmaster, Tankmasta, Team Poly, Duraplas, Rainhaven, Poly Water Tanks and a host of others around the country. The proliferation of brands is a product of the cost of trucking the tanks long distances.

Personally I don’t see this as a solution to Third World water shortages, but rather a solution for 7 star resort islands to appeal to their super rich and eco-trendy clientele. hence they are testing in Curacao.


17 posted on 03/03/2008 8:09:56 PM PST by JerseyHighlander
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To: Pontiac

FYI,
Found the projects website, http://www.drinkingwiththewind.nl/

The links and downloads section has the designs available in pdf


18 posted on 03/03/2008 8:16:21 PM PST by JerseyHighlander
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Video of the windmill, and of the membrane filter, interview of one of the researchers. (in Dutch)
http://www.youtube.com/watch?v=6tq2MC0kmqE


20 posted on 03/03/2008 8:21:09 PM PST by JerseyHighlander
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To: Pontiac

When I was in water treatment about 20 years ago the cost of the membrane would have made this prohibitive. Has that changed?


27 posted on 03/04/2008 9:07:42 AM PST by Mind-numbed Robot (Not all that needs to be done, needs to be done by the government.)
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To: Pontiac

Yes, it will need skilled maintenance and upkeep. Hopefully, if there are a bunch of them in nearby localities, they could have a skilled technician doing a circuit of villages


29 posted on 03/05/2008 9:12:18 AM PST by PapaBear3625
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