Author Topic: Solar powered desalination by evaporation  (Read 7913 times)

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la7qz

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Solar powered desalination by evaporation
« on: May 05, 2007, 11:41:25 PM »
Hi


I used to have the book "Sailing the Farm" by Ken Newmeyer. Amongst the many ideas he describes is a solar powered desalinator for seawater. He provides drawings and a description of how to make one. The desalinator is a flat box with a black felt wick inside and perspex or glass facing the sun. It looks similar tp a PV panel.


I lost my copy of the book when I was shipwrecked last year. The book is now long out of print and it may prove difficult to find a copy.


Does anyone here know of any plans for how to make such a unit? Remember, it has to be something that can be used on a small sailboat at sea. There are of course watermakers available for boats, but they are very expensive units and also expensive to run.


Regards,


Owen Morgan

Yacht Magic

Falmouth Harbour Anchorage, Antigua

« Last Edit: May 05, 2007, 11:41:25 PM by (unknown) »

la7qz

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Re: Solar powered desalination by evaporation
« Reply #1 on: May 05, 2007, 07:04:07 PM »
Hi again


I googled for "Solar still" instead of "Solar desalinator", and that brought some more info, but still not exactly what I wanted. The design in my book used a wick and fed itself with seawater from an external reservoir. Probably more efficient than one which is simply filled with water at the beginning of the day, and less risk of overspill of seawater into the freshwater which would be an issue on a sailboat.


Owen

« Last Edit: May 05, 2007, 07:04:07 PM by la7qz »

Nando

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Re: Solar powered desalination by evaporation
« Reply #2 on: May 05, 2007, 07:53:41 PM »
The book is available used :


Sailing the Farm: A Survival Guide to Homesteading on the Ocean (Paperback)

by Ken Neumeyer (Author)


http://www.amazon.com/gp/offer-listing/0898150515/ref=dp_olp_2/103-7958150-4093417


The name is NOW corrected to Neumeyer, so correct your spelling


It may cost you more to send it to Antigua.


Nando

« Last Edit: May 05, 2007, 07:53:41 PM by Nando »

GaryGary

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Re: Solar powered desalination by evaporation
« Reply #3 on: May 05, 2007, 09:07:42 PM »
Hi,


I have collected some solar still info here:

http://www.builditsolar.com/Projects/Cooking/cooking.htm#SolarStills


Not sure if what you want is there or not.


If you find something good, please let me know.


Gary

« Last Edit: May 05, 2007, 09:07:42 PM by GaryGary »

la7qz

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Re: Solar powered desalination by evaporation
« Reply #4 on: May 06, 2007, 08:01:10 AM »
Hi Gary,


Great site. The most useful link for me was:

http://www.builditsolar.com/Projects/Cooking/SOLRSTIL.HTM


The following is what was after, but the article is a bit hazy on the design, particularly how it is fed from the brine reservoir. I do have a couple of ideas for that, hazily remembered from the book.





Thanks also to Nando for pointing me to Amazon.com. I'll probably order a copy of the book when I get to somewhere I'll stay for long enough to receive mail and my finances pick up a bit. There's a lot of useful stuff in that book.


PS. Good job I previewed this before posting. Without the width restriction, the drawing filled the whole screen... :)


Regards,


Owen Morgan

Yacht "Magic"

Falmouth Harbour anchorage, Antigua

« Last Edit: May 06, 2007, 08:01:10 AM by la7qz »

nothing to lose

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Re: Solar powered desalination by evaporation
« Reply #5 on: May 07, 2007, 08:19:56 AM »
If you upload an image and use the insert image link it adds code to resize the image, not always a good thing!


like this,

img src="http://www.otherpower.com/images/scimages/1014/image.jpg" width=80%>


Change or remove the width=80% but be careful you don't use a 7" wide image which messes up the post making the screen too wide and having to pan left right to read postings.

Biggest problem I run into is I make my images a nice smaller size and the 80% enlarges them and makes them fuzzy and grainy looking.


I been reading your site and trip dairies when I have time by the way, very interesting. I hadn't e-mailed back yet, still reading :)

« Last Edit: May 07, 2007, 08:19:56 AM by nothing to lose »

la7qz

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Re: Solar powered desalination by evaporation
« Reply #6 on: May 08, 2007, 08:07:28 PM »
Yes, it didn't take me long to figure out I had to remove that "width=" thing for my photos. The drawing I used here actually looked the same size as here on the page I "stole" it from, so I was quite surprised when it turned up huge in the preview.


PS, You don't have to wait until you've read my whole site before you e-mail me :)


PPS. Probably sailing for St. Maarten tomorrow.


Regards,


Owen Morgan

Yacht Magic

Falmouth Harbour, Antigua

« Last Edit: May 08, 2007, 08:07:28 PM by la7qz »

nothing to lose

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Re: Solar powered desalination by evaporation
« Reply #7 on: May 09, 2007, 02:38:13 PM »
"PS, You don't have to wait until you've read my whole site before you e-mail me :)"


Well that wasn't it, I just got so tied up and interested in reading the site I forgot what I was wanting to ask. :)


Have a safe trip and may the winds be with you.

« Last Edit: May 09, 2007, 02:38:13 PM by nothing to lose »

Orkney

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Re: Solar powered desalination by evaporation
« Reply #8 on: May 19, 2007, 11:57:50 PM »
Have a book here somewhere with a simplified version, will try and find it the next few days and scan the pages for you.

Seem to remember it was a form of A frame of poly sheet/ glass which sits above a reservoir of salt or dirty water.

The theory being that as the enclosed A box heats up, condensation forms (which is pure water) on the inside of the poly or glass roof, this then drips down to the base of the A where it can go into a channel for collection, the reservior obviously being smaller than the base of the A.

Just have to remember which book it is in.

Kevin  
« Last Edit: May 19, 2007, 11:57:50 PM by Orkney »