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Brett Lloyd
( - F - MLife
Cooling Hot Water on 04/01/2005 10:52:39 MST Print View

I drink a lot of water on the trail, and I filter + boil each evening when I set up camp. So that I don't tread / retread the soils near watersources, I try to get all the water I'll need for dinner, breakfast, and the next day all at once. It takes a while to get it all boiled, but I prefer boiling to other purification methods.

Anyhow, I wish I knew a good method of cooling the water before pouring it into my hydration pouch. Or, I wish I had a hydration pouch that was "safe" to pour very hot liquids into.

My current method is to pour into a Nalgene container, let it sit for a while, and then pour into the hydration pouch. But the Nalgene does such a good job of insulating the water that I usually get tired of waiting and just pour too-hot water into the pouch. Then I worry that it's going to melt or be ruined and soak everything the next day on the trail. Bah.

Any suggestions from the group re: cooling water, or hot-water-safe hydration pouches?

Mike Storesund
(mikes) - F
Platypus "Freeze It or Boil It" on 04/04/2005 17:51:51 MDT Print View

I was looking at the Platypus Hoser this weekend and on the label it says "Freeze It or Boil It". With that said, I suspect you can add the boiling water directly into the bag and let it cool.

You might want to check one of these out. Even if it is a smaller one at a lower cost for experimentation.

Edited by mikes on 04/05/2005 05:37:31 MDT.

paul johnson
(pj) - F

Locale: LazyBoy in my Den - miss the forest
boiling water on 04/04/2005 23:11:56 MDT Print View

the CDC recommends that the water be boiled for AT LEAST 1 minute to eliminate Cryptosporidium. the operative words here are "AT LEAST". getting the water from 180 deg F to 212 deg. F (at sea level) & holding it there for AT LEAST 60 sec. is wasteful of fuel. the difference in temperature between the water in your pot/cup & the ambient air temperature together with the insulating properites and surface area to volume ratio of your pot/cup govern the rate at which heat transfer will take place. in some cases, it actually uses less fuel to raise the water temp from somewhere between ~40 deg and room temp (i forget the starting temp) to ~180 deg (a 140 deg delta/difference) than to raise it from 180 deg to 212 deg (only a 32 deg delta) - AND this doesn't even take into account that you need to hold the ROLLING BOIL for AT LEAST 60 seconds to kill C. parvum (according to the CDC - and who am i to argue with them?!!).

perhaps it's the necessary means of water purification in your case, but if there is NOT a compelling reason for boiling, please consider trying Aqua Mira for water purification. Aqua Mira is NOT at all like the chlorine used in some municipal water supplies. you will still need to filter out larger particles from the water - a prefilter or pack towel/bandana works fine. i'm sure Dr. Jordan can comment more lucidly on this topic if he had the time.

keep in mind that some pathogens are resistant to boiling. normally certain anaerobic SOIL bacteria of the genus Clostridium - C. perfringens which causes gas-gangrene, C. tetanus causing tetanus, and C. botulinum causing botulism, and also their aerobic cousin Bacillus anthracis which causes Anthrax. though they are NOT typically found in water, these bacteria are resistant to boiling since they form "endo-spores". in a microbiology lab, sterilization is often performed with "super heated" pressurized steam for 15 minutes (at 15psi above atmospherice pressure, water boils at ~250 deg F). fortunately, encountering in water these types of "bugs" which require such extreme sterilization techniques is extremely unlikely as water is NOT their normal habitat. therefore, boiling should kill any of the common water pathogens i'm aware of and you're likely to encounter.

if forced to, i would boil. if i had a choice, which i do, i use Aqua Mira. i have also used the Katadyn ExStream water bottles, which both filter out protozoans and bacteria, and purify water (thus killing unfiltrable viruses, like Hepatitus B). however, at ~7.5oz empty, the ExStream bottle is NOT an ultralight option. also, unless one has surpreme grip strength, it requires quite a bit of work to SQUEEZE out the last ~7oz from the bottle (it only holds 21oz to begin with).

if "re-treading" is NOT an issue at some water locations, then you could simply place your sealed container containing the boiled water back into the water source. the higher coefficient of heat transfer of water vs. air will cool it faster. also, the possible colder water temp vs. the ambient air will be a factor in cooling the container with the boiled water. likewise, any container filled with the unheated water can be used to more rapidly cool your containers which hold the boiled water. i'm NOT suggesting that this method of cooling should be considered practical, only physically possible.

hope this info helps.

Edited by pj on 04/04/2005 23:20:39 MDT.