View Full Version : Boiling Water in a Plastic Bottle?
Interesting, but seems as though it would only work on a wood fire. (http://www.metacafe.com/watch/428567/camping_trick_how_to_boil_water/)
I did that on a conventional stove eye once for a science project when I was a kid. I dont see why it wouldnt work with any heat source.
RAT
Interesting, but seems as though it would only work on a wood fire. (http://www.metacafe.com/watch/428567/camping_trick_how_to_boil_water/)
The facts are true. But I suspect the explanation is false. As is the illustration.
If you keep that bottle in the fire too long it will explode. The reason has little to do with the air in the bottle. Water boils at 212 degrees F. plus or minus a little depending on barometric pressure.
But water can be boiled in any kind of a container over any kind of flame as long as you keep the flame confined to the area of the container where the water is located. Primitive people (think American Indians) used to boil water in birch bark buckets.
Birch bark burns easily at low temperatures. But as long as water is in the bucket, the temperature of the birch can't get higher than 212 degrees or there abouts, depending on weather conditions and coming weather conditions.
The water will eventually evaporate, allowing the bark to get hot and burn. But until it does, the birch can sit over the hottest flames unharmed. I suppose someone could find a flame so hot that the birch would burn before the water could carry away the excessive heat.
But it won't happen in ordinary backpacking situations. Keep the flames from going higher than the surface of the liquid, and you can boil water in Zip lock baggies, birchbark, what ever may be at hand, over wood, white gas, alcohol, butane, whatever.
Weary
oldfivetango
03-14-2007, 21:53
Yeah,I have seen it done on a campfire a few months ago.
My reaction was then as now-would you drink water from
a plastic bottle that had been exposed to that kind of heat?
I've heard it is not a good idea to drink from a water bottle
stored in a hot automobile due to leaching from the plastic to
the water.Anyone have any research data?Inquiring minds want
to know.........................:D
OFT
headchange4u
03-14-2007, 22:17
We did a trick in sceince class when I was in high school where the teacher boiled water in a paper cup. It's the same thing that's going on in the video.
Neat trick but I would also be worried about the bottle exploding and blowing scalding water and embers from the fire all over the place. You could put an eye out like that;).
I've heard it is not a good idea to drink from a water bottle
stored in a hot automobile due to leaching from the plastic to
the water.Anyone have any research data?Inquiring minds want
to know.........................:D
OFT
Don't worry, the Lexan myth is all that: a hot-gas myth. It was disproven, Snopes has at least articles on it :)
I mean I under stand that when something boils it has to extract energy from somewhere for the phase change to occur, and this would maybe prevent the plastic from melting, but then it would explode. But it seems to me that it should melt since the fire itself even with wood is going to be over 500+F (http://www.montana.edu/wwwpb/pubs/mt8405.html).
The melting point of Lexan is ~820F. (http://hala-tec.de/mod_use/dokumente/EDBM_Lexan.pdf)
Toolshed
03-15-2007, 09:22
I tried the paper cup trick in the past, but this whole plastic bottle thing is pretty cool.
I also have concerns, not of lexan, but if using HDPE #1 (and #3 I think) and heating the bottle to 200 degrees and having chemicals leach out of the polymer and into the water.
The melting point of Lexan is ~820F. (http://hala-tec.de/mod_use/dokumente/EDBM_Lexan.pdf)
I'm not sure how lexan got into the discussion. I think the original post dealt with an ordinary soda bottle, which is a far different animal than lexan, and, I suspect, is far more likely to leach chemicals into the water.
Anyway, that's why I rarely use a soda bottle as a light weight water carrier. I boil suspicious water to avoid the weight of a pump and the inadeqate protection of chemicals.
Weary
I'm not sure how lexan got into the discussion. I think the original post dealt with an ordinary soda bottle, which is a far different animal than lexan, and, I suspect, is far more likely to leach chemicals into the water.
Anyway, that's why I rarely use a soda bottle as a light weight water carrier. I boil suspicious water to avoid the weight of a pump and the inadeqate protection of chemicals.
Weary
Yeah, I am not sure why I even put that. It was early in the morning still. I should have put
HPDE melting point 248-266F (http://en.wikipedia.org/wiki/Polyethylene#Physical_properties)
And then my argument now makes much more sense.
Dances with Mice
03-15-2007, 13:23
Yeah, I am not sure why I even put that. It was early in the morning still. I should have put
HPDE melting point 248-266F (http://en.wikipedia.org/wiki/Polyethylene#Physical_properties)
And then my argument now makes much more sense. HDPE - high density polyethylene isn't very clear and is used to make milk jugs and products that are heavily pigmented like garbage cans, detergent bottles, margarine tubs. I wouldn't put those in a fire. HDPE melts easily. 250'ish F is really low - it's just above the boiling point of water.
OTOH, soda bottles are usually PET - polyethylene terephthalate, more commonly known as polyester. Melting point near 490F.
But I'd be uncomfortable near any tightly sealed container that's being heated. Sooner or later a pop bottle of hot water is going to pop.
Skidsteer
03-15-2007, 18:04
HDPE - high density polyethylene isn't very clear and is used to make milk jugs and products that are heavily pigmented like garbage cans, detergent bottles, margarine tubs. I wouldn't put those in a fire. HDPE melts easily. 250'ish F is really low - it's just above the boiling point of water.
OTOH, soda bottles are usually PET - polyethylene terephthalate, more commonly known as polyester. Melting point near 490F.
But I'd be uncomfortable near any tightly sealed container that's being heated. Sooner or later a pop bottle of hot water is going to pop.
Dances, what are your thoughts on pouring boiling water in HDPE?
Dances with Mice
03-15-2007, 19:44
Dances, what are your thoughts on pouring boiling water in HDPE?It would not be a problem. HDPE's the choice of many commercial 'food safe' designated containers.
Skidsteer
03-15-2007, 19:53
It would not be a problem. HDPE's the choice of many commercial 'food safe' designated containers.
That's a shame.
Now I have to find an alternative explanation for the Voices....
Thanks for the info. :)
Dances with Mice
03-15-2007, 19:55
Dances, what are your thoughts on pouring boiling water in HDPE?Come to think of it, way back in my homebrewing days my primary fermenter was an 8 gallon HDPE container. It saw a lot of boiling water.
Skidsteer
03-15-2007, 20:10
Come to think of it, way back in my homebrewing days my primary fermenter was an 8 gallon HDPE container. It saw a lot of boiling water.
Sheesh, you're a homebrewer? It's all making sense now.
I have used(and still have), a ten gallon tower brewing set-up for years. :)