Dry Ice Creativity

[boiceboy]

I have been reading extensively about DIY CO2 setups, getting ready to make one myself after I move. Out of curiousity, can anyone think of a useful way to use dry ice as a source of CO2? I can get a ton of it from work when I want, the only problem is I can't think of a way to really make it last efficiently. I'm a newbie, so please don't bash this open question. More of just a fun theoretical post.

Anybody have any creative ideas? I'm sure I'll just go with a standard yeast mix, but I'd like to see what more than just my mind can think of, which was nothing really....

 

[got_nailed]

This is talked about a lot but how would you control how fast the dry ice melts (gives the Co2 back)?
What would you put this in? You need some presser but not to much.
How much is dry ice where you live at?


You can get a good Co2 setup for about $299 that will turn off with your lights or a timer. Refill the tank 2 or 3 times a year for about $20 to 30 a fill. But living in San Diego you could get a tank dirt cheap and get a good deal on refills.

I don’t think that dry ice will work, but if it dose I don’t think it would cost less in one year than getting a presser injection system form a 5 or 10 pound bottle.

 

[QCppg]

If you could get a disposable styrofoam cooler and wrap that with insulation you might be able to use the dry ice for CO2. Provided the temperature remains low you can control the evaporation rate by limiting the surface area of the mass (IE use one big piece instead of a lot of small ones).

 

[beviking]

Yes but evaporating dry ice doesn't create any pressure so how is it going to overcome the water pressure at the other end of the tubing? Wait a minute...a solid turning to a gas expands so it must create some pressure. I don't think a styrofoam cooler could take much pressure.

I don't have any ideas on how to make it work but I say...if there's a will there is a way!!!!

 

[TKOS]

Could it be dissolved in a bottle with warm water. Then introduce it to the tank? Of course the bottle would have to be sealed and the pressure would build up and go into the tank. But then you would still run out pretty quickly I would assume.

 

[ChicoRaton]

evaporating dry ice doesn't create any pressure

....:laugh: HAHA! you've never put a few chunks of dry ice in a plastic soda bottle have you?

[edit] woops didn't read your whole post... I was laughing too hard my bad... but yes, it can create several hundred PSI of pressure... enough to get to the bottom of a pretty big tank.[/edit]

I think the best way to control the rate of the dry ice would be to have a large resivoir like a big trash bag. put a small air pump inside the bag, and connect it to a gang valve so you can turn the rate down. Then run another tube into the bag from a resealable container. put the dry ice in the container, it fills up the trash bag, and the air pump always outputs a constant flow of co2 into the tank.

Not pretty, takes up a lot of space, but effective if you have a free source of dry ice.

 

[Watcher74]

That's the truth about pressure and dry ice. Throw some in a cup of water and you'll jump out of your seat from the reaction.

Wish I could make some myself. Awful fun stuff to play with.

 

[QCppg]

The reason for using a styrofoam container is so you don't build up lethal pressures. As others on this thread have stated dry ice can generate explosive pressures if confined.

 

[got_nailed]

After reading ChicoRaton post… I was thinking of the days when we would put the dry ice in a paint can (with paint in it) and put it on a door step or what ever you wanted to paint. Seal it up god and run back about 60 feet. The top would pop off with most of the paint in the can and it would be one he!1 of a mess.

But yes it would give off some nice presser. I just don’t see a good way to put it into something that would hold the presser. As long as it is keep at a presser I don’t think it will “melt.” The more I think about it I’m thinking a gallon pickle jar with a small peace of dry ice will work if you can get the seal to hold 15 lbs of presser. And yes use a hole sealed off and run the tubing into the tank. I just think this should be kept in a heavy duty rubber made container and a tight fitting lid with a few 1/2” holes in the top.

I still think that the cost will be a lot higher in a year then getting a 5 lb tank and the rest of the setup.

 

[ChicoRaton]

But yes it would give off some nice presser. I just don’t see a good way to put it into something that would hold the presser. As long as it is keep at a presser I don’t think it will “melt.”

That's the whole purpose of the garbage bad resivoir. You don't want any pressure. the air pump takes care of that. Oh, and the only time dry ice will actually melt is when it's under pressure. otherwise it sublimates. It really does go liquid-solid though if under high pressure. At high temp AND pressure, it becomes supercritical, which is where it's like a cross of a liquid and a gas. I'm not sure about supercritical gases though. I slept through that day of chemistry class.