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Gunfixr
02-19-2012, 10:30 PM
Has everybody verified that any local groundwater they pull will be fresh water, as opposed to salt water or brackish water?
While I can pull water all year round from a source about 1/4 mile away, it's brackish at best. This means I will have to remove the salt as well as any contaminates.
While distilling is relatively easy and removes both salt and contaminates, it requires a heat source, meaning using precious fuel reserved for cooking and heating.
A desalinator will take care of this via reverse osmosis, wherein the water is passed through a special membrane which will not let the salt pass. The only problem is that it takes a fair amount of pressure to do this. Most desalinators are power driven, either 120v or 12v. However, Katadyn makes hand operated units in a couple sizes.
They are not cheap.
One is on the short list to be acquired.

Grumpy Old Man
02-20-2012, 05:15 PM
Try making a solar still to cut down on the energy requirement; not fast but they are free. Also, a reverse osmotic process acidifies the water somewhat, say down to about a 6.7.

As far as stills here's a link

Stills - Stills & Filters (http://stillspirits.com/us/filters/stills.html);)

helomech
02-20-2012, 07:10 PM
solar still like Grumpy says. You can make a bunch of them for very little cost.

Gunfixr
02-25-2012, 04:30 AM
True you can, but they have limitations.
There's a family of 4 living here, with a standard requirement of 1 gallon per person per day meaning I need 4 gallons per day minimum. Unless you've got plans for some "super solar still" I haven't seen, these are kind of a last-ditch-I-gotta-have-any-water-I-can-get kind of thing. They produce rather small amounts rather slowly, unless you live in a desert. Here on the East Coast, cloudy and/or rain is regular, meaning no sun, it's only really hot for a short time, and the sun track on our property isn't that good. Also, the yard simply isn't big enough for that many holes.
While I can set up to collect rainwater and filter it, I'll need supplimentary methods for dry spells. Actually, when the ground is good and wet, any holes would likely fill up, as there is only about 8-10 inches of soil, and then clay.
The investment on a desalinator, with close groundwater all year long, seems better to me than hedging my bets on setting up solar stills and hoping the sun stays out.

helomech
02-25-2012, 12:24 PM
True you can, but they have limitations.
There's a family of 4 living here, with a standard requirement of 1 gallon per person per day meaning I need 4 gallons per day minimum. Unless you've got plans for some "super solar still" I haven't seen, these are kind of a last-ditch-I-gotta-have-any-water-I-can-get kind of thing. They produce rather small amounts rather slowly, unless you live in a desert. Here on the East Coast, cloudy and/or rain is regular, meaning no sun, it's only really hot for a short time, and the sun track on our property isn't that good. Also, the yard simply isn't big enough for that many holes.
While I can set up to collect rainwater and filter it, I'll need supplimentary methods for dry spells. Actually, when the ground is good and wet, any holes would likely fill up, as there is only about 8-10 inches of soil, and then clay.
The investment on a desalinator, with close groundwater all year long, seems better to me than hedging my bets on setting up solar stills and hoping the sun stays out.

Desalinators have a life span, and it is not that long. Can't remember how long, but we have 3 of them in each of our helicopters. They are also very hard to pump. Do you have access to lots of wood? If so than make a actual wood burning still.

Gunfixr
02-26-2012, 08:12 PM
Well, for the model I am interested in, there is no specific lifespan that I can find. I apears that it will last indefinitely, so long as the membrane is kept clean and free of excess bacteria. The unit I am looking at (Katadyn Survivor 35) will produce about 1-11/2 gallons per hr. Yes, it will be hard to pump, but not as hard as the smaller model. Perhaps the smaller model was in the helicopters. In addition, the desalinator is designed to work in seawater. Our ground water is only brackish, which would make it much easier.
If you can show me a solar still that will produce a minimum of 4 gallons per day, with about one half day of sunshine, I am certainly interested.
Production of 5 gallons per day would be better, I have 4 people living here, so 4 is the absolute minimum. I do not have full sun all day in the yard, and only have sun at all hit the ground in my yard part of the day, even if I move it around to follow the sun. It would have to be easily portable.
The only way I'd have enough wood is if I started stripping down the neighbors' houses.
I'm pretty sure that's not going to go over well.

helomech
02-27-2012, 12:03 AM
Seems like for you there is not many options. I am using all options, except for a desalinators, but I have those options available to me. I do believe the membrane does not last forever, even with cleaning but I am not positive on that. Ours don't last forever I know for a fact.

Gunfixr
02-27-2012, 07:49 PM
I agree they won't last forever. What I meant about life span was that it was not severely limited.
For instance, the small water bottles with the built in filters in them. They usually last about 50 gallons. While great for a "get home" emergency, it's not what I want for SHTF.
The smaller unit, the Katadyn Survivor 6, only puts out about 3/4 gallon per hr. Also, the larger unit is supposed to be engineered to more efficiently utilize the pumping pressure to make the effort a little less. So, 4hrs of pumping to make the minimum 4 gallons isn't the plan I like, but it beats death from dehydration.
They do need rather high maintenance. The membrane must be kept wet, and anti-microbial agents must be used to keep the membrane from growing bacteria. It'll be a PITA, but right now, I haven't found any other options.
I live in an urban environment. Yeah, I know, I need to bug out to my BOL. Well, I don't have one, and am not likely to be able to get one in the forseeable future. There are some trees about, but they won't last long. You can bet propane to fill tanks will be unavailable. I will set up to collect rainwater, but I am sure there will be times where that will prove insufficient. The groundwater is always available, but brackish.

Sniper-T
02-27-2012, 08:04 PM
There was a brief discussion on this once before, here: http://www.shtfready.com/food-water/turn-salt-water-into-drinking-water-767.html

Gunfixr
02-28-2012, 02:56 AM
Yeah, but back to needing fuel again.