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Posted

Definitive and final answer(s?) please

1 I am on a desert island

(No not that type there are no coconut trees-it is a desert)

 

2.There is limited water one keg of fresh water has been saved from my shipwreck

(No the island is not Australia-will you stop it)

3. There is no more freshwater anywhere

(Yes I tried digging a hole. Please take this seriously)

So the question:-

(No I have no plastic either for a solar still OK:doh:?)

How much can I dilute my fresh water with sea water (there is NO GIN!! PLEASE!) so that I survive the longest?

(OK, then assume the barrel of water won't go off. It has a super preservative in it OK-no it won't preserve me!!!~-This could save you life one day you know!!)?:)

Is this amount the same for young, old, male, female, weather hot cold?

or

What part of the ocean my island is in.

or

If I get the sea water from the top or bottom layer of the sea water?

Posted

In the unlikely event that you find yourself in such a terrible situation, Drink the water from the keg, (presumably in a prudent fashion), and then fill the keg with seawater and find a way to capture the evaporation.

 

If you can find a way to capture the evaporation/condensation you could repeat indefinitely, and would likely die from starvation and exposure instead of dehydration.

 

As far as diluting sea-water, that could depend on the individual themselves and how much water the person requires.

A large person needs more water, so the question becomes very subjective in terms of "how long, how much?"

Posted

What do ya know, they did a study with rats:

Research on laboratory rats confirmed that drinking sea-water when dehydrated, was not beneficial and caused impaired renal function. When the concentration of sea-water in the drinking water is gradually increased there is a gradual increase in water uptake and corresponding urine excretion. At 50% sea-water the maximum uptake and excretion is reached. Following this there is a decline in appetite, water uptake and urine secretion. When on 100% sea-water, the creatinine clearances were greater than on tap water, while urine/plasma osmolalities (U/P) averaged 7. The only higher U/P was found in animals drinking sea-water when dehydrated, i.e. a U/P of 11. The urea metabolism appears to be suited to either the need to conserve body water, up to 50% sea-water, or to guarantee an adequate urine production, from 50% sea-water to pure sea-water. It is suggested that when a man is stranded at sea it is not advisable to drink all the fresh water and then be compelled to drink sea-water when dehydrated. It is better to slowly increase the sea-water uptake. This will prolong the time before sea-water needs to be drunk and result in only minor metabolic changes. Return to fresh water will be followed by an immediate return to normal homeostasis.

 

So.. step 1: don't mix the fresh and salt water in the keg. There's no need to introduce bacteria and whatnot in the keg. If you don't have a smaller container to mix them in then just drink them in small amounts alternatively. Step 2: never more than 50% seawater intake. Step 3: slowly increase the level of seawater (presumably from 0 - 50% linearly for as long as the freshwater is going to last) which might require a bit of calculus. If you don't know calculus... well... sorry, you're gonna die :phones:

 

~modest

  • 1 year later...

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