Dry Ice for portage barrels?

-- Last Updated: Oct-10-08 3:30 PM EST --

Does anyone have any experience using dry ice to cool 30 or 60 litre barrels being used for a food pack? I really like the barrels, but would appreciate the ability to give a longer, deeper chill to perishables. I'm particularly interested in what type of insulation should be used next to or around the dry ice. I know that you can't use dry ice in a regular plastic cooler, so assume that the same would hold true for a barrel. Any assistance/solid information would be appreciated.

What I’ve read and heard …
… some friends used dry ice in their cooler on an extended camping trip and all their beer got stuck in it. It was really funny. I think they allowed it to get wet, which is a no - no.



I’ve heard you should wrap it in Newspaper and lay it on top of your food. Freezing your food will also allow perishables to stay cold longer.



Take food out in plenty of time to use so it will thaw out.



Some say it gives their food a chemical taste, but if food is sealed - can’t see that happening.



I thought about taking it on an Everglades trip, but don’t feel like dealing with it.



Good luck!



There is a lot of info out there if you Google Dry Ice.

Be careful about packing it in your car

– Last Updated: Oct-10-08 4:45 PM EST –

CO2 is a toxic gas that causes the PH in your blood stream to drop, as little of 3-5% in the atmosphere, makes you drowsy and causes increased heart rate and can lead to death. There are several known accidents where people have packed dry ice in a vehicle or small airplane and this led to unconsciousness and death caused by loss of control of the vehicle or aircraft because of breathing the emitted vapor in a confined space. CO2 is used to asphyxiate laboratory rats quickly in experiments, so make sure you don't use large amounts in an enclosed space.

People confuse Carbon monoxide which is poisonous by binding to hemoglobin, and thin CO2 is safe, it's much safer but should be treated with care.

Dry ice bombs are another matter, you could probably make quite a bomb with a waterproof food container.

Why?
Maybe we can help you more if we understand what shortcoming of a convential cooler with ice /freeze packs you are trying to overcome.

A good question, but…
…the reason for my curosity is nothing fancy. I’d simply like to make it possible to use barrel packs for a 10-14 day trip and keep as much food as cold as possible for as long as possible. My thoughts so far are to go to two 30 litre barrels, making one a “freezer” and another simply “chilled.” But I’m most interested in the best way to do the “freezer” unit. I have Googled dry ice (just as becca recommended), and have learned a lot. One of those things is the truth of seadart’s comment that a waterproof container w/dry ice could make a great bomb. Hmmm, maybe I’ll stay with the old-fashioned way with “wet” ice, just like I’ve been doing it since the 60s!

newspaper or better terry towels
keep the towels damp and if you allow for evaporation and the climate is dry enough to allow evaporation, food will stay chilled for a long time.



After six weeks out in the boreal forest the darn butter was still as hard as a rock even though temperatures were in the upper 90’s.



Ice in blocks lasts far longer. Use those two liter soda bottles and freeze water in them. Not only will you NOT have a mess, the ice will last longer. And line your barrels with newspaper.



Betcha your great granpa used newspaper for insulating shoes in the winter. Lots of houses from the 1910’s that have not been remodeled still have newspaper for insulation.

Ice Cream in July
I have friends who have gone the Dry Ice route. It’s the only time I’ve ever had ice cream on a camping trip. Even the best “wet ice” won’t keep ice cream in the summer … or just about any other season. But, why can’t you use it in a regular plastic coooler? I think that’s what my friends had. They used some corrugated cardboard to provide some insulation between the dry ice and their food so it wouldn’t get too frozen. I’ll forward them the information about the hazards of dry ice.

Dry ice in a regular cooler
I wasn’t very clear with that part of the question. What I should have said was: I know that you can’t use dry ice in a regular cooler without wrapping it in something first. So what should I wrap it in?" The respndents here have really answered that for me with newspapers or terry towels. So, I think I’m good to go, except I’m still pretty leery of carrying a “bomb in a barrel” around on my back or in the canoe. I think I’m going to stick with frozen bottles of water (I agree w/Kayamedic on this, they are my long-time choice.) I’m going to experiment w/dry ice when we have enough people to portage an extra cooler; I just love LittleRed’s thought of ice cream many days out on a trip!

I wouldn’t worry
about the bomb in a barrel. That would only be a concern if you added water to the dry ice.



I’ve used dry ice in a regular plastic cooler on canoe trips before with great success. I wrapped the block in brown paper (like paper bags etc.) and it not only kept the food good and cold, it only shrunk about 20% over 3 days in July. If you get the dry ice from a distributor, they can usually tell you how much you will need based on the length of your trip and the container it will be in.

What about the pressure gradient?
Barrels are pretty tight sealing. If the dry ice carbon dioxide expands, when you open the clamp I can envision the top blowing in your face…



Perhaps the cold negates this pressure.



I dont want to try this experiment. I have experience with barrels and know that sometimes they develop suction and other times they are hard to get the lid down on.

many packages
I would think that several small packages, planned for a few days each, would be better than the approach of two barrels with one freezer and one refrigerator, where you have to open each one daily. Label and stack the packages for future days some place where they’ll stay undisturbed, and enclose them in several layers of material, possibly some kind of emergency or otherwise useful supplies that you won’t be needing in the first few days (ponchos, extra rain tarps, bed sheets, extra newspaper for fire starting, etc.).

frozen drinks
I started wondering about something, does anybody freeze canned drinks, like beer and soda, for extended camping trips? I don’t usually pack these two for camping trips, at least not beyond the first day or two, so I’ve never tried. But I remember in my childhood, we used to freeze cokes overnight and take them to school. Once in a while the freezing would open a leak in the can, but usually it just made it bulge out on the bottom.



How would beer do - would the alcoholic content make it expand less when it freezes? I know it would freeze at a lower temperature, and that’s a good thing.



Hmmm, and that leads to another idea. The higher the alcohol content, the lower the freezing point, right? Maybe what you need is an ice cube made of a fifth of bourbon for each two-day package that you set aside for later days on the trip…

Ice chests have no seal, gas leaks out

– Last Updated: Oct-11-08 2:26 PM EST –

The seal of ice chests are poor and the modern ones made in china have no seal at all. But 44 grams of dry ice (about 3/4 of a cup) becomes 22 liters of gas as it evaporates. Thus a sealed container will become highly pressurized as the system gains heat energy. Adding water is not necessary. It's just a matter of how fast heat warms up the contents of the container so it can turn to the vapor state, when the pressure vessle fails all of the CO2 becomes gas instantly.

When I was bored in graduate school we made simple dry ice cannons that would propel a projectile 300 yards form the Chemistry building across the University of Michigan Quad. My son's friend with a large pepsi bottle made a dry ice bomb that dug an 18 inch crater in the beach... so I still would say watch putting it in a sealed barrel.

I freeze it all if I can.
If it can be frozen and not damaged then I freeze it. This allows me to carry a smaller cooler and things in the cooler have a lower starting temp. If I’m using a really small cooler I put the cooler in the freezer overnight before I leave.



The small individual serving orange juice containers make great ice blocks. They can bet set out as need to thaw. We routinely freeze those nasty Caprisun concoctions in the mylar pouches for my daughter to take to practices or for a snack at school.



I’ve frozen beer accidentally by forgetting I put one in the freezer to chill. The can bulged to the point that it could have ruptured. If you take that approach put the cans inside a plastic bag so if one blows out you don’t spend half the day cleaning the freezer.

Dry ice in 2L bottle.

– Last Updated: Oct-12-08 12:32 AM EST –



Wowzer, can you imagine a portage kegger filled with the stuff, when a teensy Coke bottle does this:

http://www.youtube.com/watch?v=eHh_JCFKptQ&feature=related

Go 2L for this effect:

http://www.youtube.com/watch?v=59T-EddV1cA

(gotta laugh how his glove is in smithereens and he instinctively counts his remaining fingers).

You rock for just considering the idea, original poster. And I thought my brother was insane when he jumped his moped over the neighbor's garage.





Whoa, wait, nearly a record dry ice bomb
http://www.youtube.com/watch?v=w4vB0g2_mmA&feature=related



But you have suggested 60 gallons, original poster. So you will have topped this vid. Just add the ice and add water. Or wait until portaging when a beer or a Coke springs a leak. If you hear a hissing, I’d say you still have–according to youtube university, here-- about 14 seconds to drop the barrel, run away and get out your camera for the video.

Dry Ice or Sodium Carbide?

The original idea of two barrels…
…was to keep the “freezer” barrel sealed and cold for multiple days, opening it only to transfer occasional hard-frozen stuff to the “refrigerator” barrel, thus allowing those items to 1) defrost and 2) cool what ever else was in that barrel. I still think my theory is pretty good, but watching these (admittedly wonderful/terrifying) videos of dry ice bombs in action, I think that we may have to work on the practical aspects of “dry ice in a sealed, watertight barrel” for just a bit longer! But, kayamedic, I now have other ideas about what can be done with two litre bottle (perhaps after trying out memphis’ bourbon ice cube idea!)

dry ice, whiskey ice, sea ice
Just looked up some numbers - dry ice freezes at -109 F. Pure alcohol freezes at -173 F. Most drinking whiskeys are 80-100 proof, or 40-50% alcohol witht he rest being mostly water, so the freezing temp would be -50 to -70 F.



Making ice cubes from the alcohol is problematic, unless you know somebody with a commercial freezer. Most household freezers only cool down to about zero degrees F. On the other hand, a zero degeree fluid is going to cool better than a 32 degeree solid (regular ice), but it requires you to find the right kind of container. Or, you could buy dry ice ahead of time and use it to freeze your whisky ice into a solid block.



Dry ice is convenient because it comes in blocks that can just be wrapped, it doesn’t need a leak proof container, and it just goes away when it melts. Whiskey ice doesn’t go away and must be handled when it melts. On the other hand, this provides a convenient excuse for a subset of a large camping party to stay behind one day late in the trip and “clean up the camping gear, especially that nice freezer that kept everything so cold - you guys go ahead and take the kids on that side trip up the canyon.”



Another alternative also occurred to me - making saltwater and freezing it. Saltwater that is fully saturated (keep adding salt and stirring until it just settles out in the bottom) has a freezing temp of -6 F. Or, to be more sure that your freezer can actually make it solid, just use a ratio of 1.5 pounds of salt to a gallon of water. That mixture should have a freezing temp of about +2.5 F, still very much colder than plain ice.