Question,

I live next to the ocean at the moment so water would not be in short supply in an emergency, however how do I take this Sea water and make it drinkable? Is there a filter I can purchase that would remove salt along with everything else? Should I make some type of homemade distiller that can run on solar energy? (Sunlight, not a panel)

I'm assuming we have a power outage and want to outlast my emergency supplies. I keep 60 gallons on hand at all times rotated of course.

I have small kids so feel a strong desire to know what to do in case of emergency, and don't want to rely on agency's during a disaster.

Thanks,

Yes, there are "reverse osmosis" pumps that will remove the salt and filter sea water to make it potable. Usually found on life rafts and for use in life boats, they come in small portable sizes up to large industrial units.

Thanks bws48, any idea were I could get such a thing?

Maybe a boat shop?

Mr. Ritter did a whole article on this subject, search the main webpage and find it. He recommends and I agree on the PUR Survivor with a leg strap. There are bigger ones if weight/space are not an issue.

You can find these on Ebay very cheap considering the retail at about $800 +/-. Just search PUR reverse osmosis.

If push comes to shove boiling the water and collecting the steam or just leaving it in the sun, will produce drinkable water and edible salt. The sky is the limit and the imagination could run wild with ideas on how to collect the fresh water. I know a desert survival trick is to put a tarp over a hole with a pebble in the middle (making and upside down cone) and putting a container under the point of this cone, something like this could be done over a container/puddle of seawater with the fresh water catcher floating on the surface of the seawater.

I have a pressure cooker I could pull out the safety release plug put in a flared copper tubing used in plumbing, then coil the tube as a condenser and let it drip into another container. This is my standard idea if a "nuclear event happens as well, but then I would also filter it through my Big Berkey filter too. Everyone has an old pressure cooker laying around somewhere or can stop by the thriftstore and find one thats not good for anything else.

People have hit on the main two methods you could use--reverse osmosis and distillation. Both methods are energy intensive and don't produce that much water quickly.

Depending on your storage space and how long you want to be prepared for, then IMHO simply storing more water probably makes the most sense rather than trying to desalinate seawater. Sixty gallons is an admirable amount of stored water. Far more than most people. If you can swing that much, then perhaps another 60 is doable for you.

Military surplus stores, of course- lifeboat desal filter

Sadly, the replacement part is more expensive that the unit. Back in the '60's, surplus stores used to carry a variety of life boat supplies, including shark repellent (which makes a mess in a swimming pool, and has been effective for decades in keeping the sharks out), and deslainization chemical blocks, about 3/4" by 1" by 3". These dissolved in the water and formed a black sludge at the bottom, and turned clear sea water into sludgy brackish water. Not sure of the chemistry, but it looked and tasted like charcoal was involved.

Thanks for the ideas all.... I will look for that Article Doug wrote as well. upping my stored water is easy enough, a family of 5 goes through water quickly. You never realize how much we depend on the store until you purchase a "few months" supplies and quickly run out! When I bought the water I thought wow that will last forever, well it goes quick.

I would agree that storeing more water might be better than removing the salt from sea water.
Reverse osmosis is a well established technology but requires considerable human effort (in the case of lifeboat type units) or electricity in the case of larger units.
Futhermore anything mechanical is liable to failure, therefore a spare would be sensible which adds to the already substantial cost.
I believe that coastal seawater can be too dirty for optimum use in reverse osmosis plant, many yachts are fitted with such, and the advice is generally only to use it well out at sea, not in port or near a coast.

If you have a garden that requires watering, consider installing a large tank, kept filled from the mains water supply by use of a float valve.
Use water from this tank to water your garden by means of a small pump, this will ensure that the tank only contains fresh water, that can be used for household purposes.
Your existing 60 gallons would last a long time if reserved only for drinking, use the tank water for washing, cooking and laundry.

Hmmm. Ray Mears did something like that in his recent Australian series, and it didn't work too well. The problem was cooling. He got some water out of it at first, but then the steam heated up the tubing and everything else it touched, and started escaping to the air before it condensed. He ran it for several hours without getting much water. And it used a lot of fuel.

A third pot might help, full of (sea) water that you can run the tube through, to cool it.

Presumably we are aiming to produce between two and four litres of water a day. I imagine even with half-decent cooling, much of the source water would be lost as steam, so you'd have to put more water in than you got out. How long does it take to boil 8 litres of water dry? Is this really practical?

Lab condensers run a tube carrying the distillate vapor through an outer tube that has tap water running through it for rapid cooling. Moon shiners ran it through long pieces of copper tubing- also in a water bath. Nastier moon shiners ran it through old car radiators, with considerable leaching of lead from the soldered joints. This lead to irritated customers raising the 'shiner's lead level by ballistic means.

A couple of local folk devised a wood fired water heater by tossing a coil of copper tubing into the bottom of their wood stove, attached to a barrel of water located higher than the stove. The water was supposed to circulate by convection. Worked okay until one of them tried to control the process by installing valves in the lines. Turned a sweet little convector into a steam bomb.

What about Watercone?

http://www.sportsmansguide.com/net/cb/cb.aspx?a=415424

Expensive, $799, but the claim is it will do 1 gallon per hour @ 98.4% salt rejection?

I have been doing a lot of experimentation lately with solar salt water stills. I'm 9 blocks from the Pacific Ocean in So Cal, and there are almost no natural fresh water sources here-abouts. I've tried a variety of setups and, by far, the best setup I've achieved is with a thin clear plastic bowl and lid available from the Smart and Final warehouse stores out here. You put the lid, really a big shallow bowl itself, upside down in full sun, sit a tray of some kind full of salt water in the lid, then sit the upside down bowl itself down on top of the whole thing snapping it onto the lid to get an airtight seal. The salt water evaporates and fresh water condenses onto the inside of the upside down bowl and runs down the steeply sloped sides collecting in the lid. Even running 4 of these stills during all the sunny hours (not as much as you might think considering that a part of everyday there's high fog obscuring the sun), I've been lucky to distill out about 8 ounces of fresh water. One thing that helped was to put a pile of black rags as kind of a wick in the salt water. This seemed to increase the surface area available for evaporation and helped improve the output somewhat. I would work further on refining this addition if I spend any more time on this project.

Thanks, sotto, that's pretty interesting. 8 ounces isn't much, but at least it doesn't take time or fuel, once it is set up.

Read "Into a Desert Place" by Graham McIntosh. He walked all the way around Baja California, on the coast. A large part of his drinking water he got by boiling seawater in a plain old tea kettle with a few coils of stainless steel tubing running out of the whistle hole...

He has apparently written three more books on the subject, the most recent titled "Marooned With Very Little Beer." I haven't read any of those yet...

You might also want to consider the new forward osmosis water filters from HTI. They now have a version that will filter seawater, and their entire line to me seems to be the easiest filter system to pack and use. I haven't actually ordered from them yet, but (unless anybody here has negative experience with them) I'm planning on getting their camelback style filter for my BOB.

http://www.htiwater.com/hti.html
http://www.htiwater.com/seapack.html?Vl=5&Tp=2

UPDATE RE ABOVE

Another reason not to use reverse osmosis plant on land.
Such equipment requires several gallons of sea water for each gallon of drinking water produced.
This matters not on a yacht or ship surrounded by infinite supplies of sea water, but would be a serious drawback if had to carry the water from the sea to a coastal home.

Reverse osmosis watermakers take in seawater and produce a small amount of drinking water, and a much larger amount of slightly more concentrated brine, which is returned to the sea.
Engine driven machines also use this water for cooling.

If it gets cold enough the ice that forms is relatively fresh. Repeated freeze/thaw cycles and slow freezing rates increase the purity and ice on top of sea water is often drinkable water.
You can often tell by the colour how good it is. Clearer is better than greyer.
The effect is strong enough that you can have pools of fresh water form on old ocean ice in the arctic.

Another odd feature of some beaches is that fresh water often sits in a layer just inland from the beach and on top of the salt water layer in the ground. (Ghyben-Herzberg lens)
If the salt water has formed a water table the fresh water floats on top and for every foot it is higher than sea level it will be 40 feet deep. It tends to form a lens shape like most other floating liquids, so it can be thin near the edge but quite deep if it covers much area.
So you might find water if you dig a hole on the land side of the beach, especially if it is sandy.

Another point is you can use the seawater for many things you don't need drinking water for.

Rainwater is 20 times cleaner than any ground water.

Invest in a sturdy above-ground swimming pool and a tight cover, and collect water off your roof. Google 'texas water harvesting' for more info.

One inch of rain on a 1000 sqft home or garage will collect 600 gallons of water. A 12' diameter pool that is 52" tall and filled to 44" holds about 3,200 gallons of water; 5" of rain will fill it.

If you have a home roofed with asphalt shingles, and a garage with a metal roof, use the metal roof.

Keep your kids out of it.

Sue

Just throwing some ideas in, I know we've discussed it before and it is a repeat of others ideas. I have 2 salt water desalinizers due to I live near the ocean as well, my two setups are a PUR Survivor 35 I had gotten off e-bay for $250 and a e-still that I bought almost 15 or 20 years ago, don't remember how much I paid for it. It is my favorite (e-still)between the two because there is no filters or screwing around with storing it with biocide.

My So Cal city, in its infinite capacity to pass more and more building code requirements, now requires that any remodeling or new construction incorporate a rainwater collection and ground-water dispersal system on the property. Essentially this means that you have to install rain gutters and downspouts on the house, if none existed previously, and collect all the roof run-off and send it to a rock-lined and vented covered pit on the property. OR, collect the run-off in rain barrels for slow dispersal over time via a valve on the barrel. This is required even if you just replace a garage, as I recently did. So, I'm not going to worry so much anymore about solar stills (see my earlier post above), and just rely on my rain barrels for backup water, assuming we get our normal 14 inch annual rainfall in the indefinite future. I have a battery-operated UV water Steri-Pen (the Journey) with lots of batteries and lots of coffee filters.

And given the possibility of little or no rain, I'll keep the barrels filled in advance with the garden hose.

Given plenty of fuel, boiling water into steam is easy, the problem is in providing sufficient cooling to condense all the steam into drinking water.

One option is to pass the steam through a coil of pipe in a container of cold seawater.
This water will soon become heated, and should be replaced with cold. The heated salt water should be added to the water in the still, thereby slightly reducing the fuel needed.

There used to be a purpose designed product for distilling seawater, that worked semi automaticly.

Another option would be to use a long length of copper pipe, perhaps fixed to the wall, steam in the top, fresh water out the bottom.
The large area of hot copper pipe could be used for drying food,or laundry.

Please take great care that any improvised boiler or still cant build up any significant pressure, it would explode.
A very simple safety device consists of a vertical pipe open at both ends. The lower end is immersed in the boiling water, the upper end is open to the air.
Any build up of pressure will force the water out of the tube thereby emptying the boiler.
To avoid danger of scalding, the pipe should be angled away from persons.

Are we making water or the "liquid of the gods"

'Are we making water or the "liquid of the gods"'

Dual function, man! Triple function if you include using the condensation tubes for hanging laundry.

First, you make your water drinkable, then you generate some income/barter goods.

Sue

I think the Dutch drank only beer for decades--babies, kids, adults, all of them; cuz that's the only potable "water" they had.

They knew how to make beer, but the other stuff was too tricky.

My uncle said the trickiest part of making beer was getting the caps to stay on. Apparently the Dutch mastered that early on.

Sue