Filling CO2 tanks with dry ice...

[Brokeass_baller]

A while back, somebody here spoke about how he/she had filled their 3.5oz tank with dry ice and had successful results.

At work, we picked up a few hundred pounds of dry ice pellets to cool some bushings we need to replace. And I had two 20oz-ers sitting around, so I gave it a shot. Filled one to 18oz, the other to 17oz.

Do ya think they'll blow up? Lol

[Brokeass_baller]

Valves are on and everything's good so far. Lol

[NONOBLITUS]

Wait , what ? staying tuned out of curiosity

[DocsMachine]

Er, 20 ounces of dry ice IS 20 ounces of room-temp liquid CO2.

It's like filling a 16 ounce glass with 16 (fluid) ounces of crushed ice, and wondering how much water you'll end up with.

As long as you filled the tank by weight, and not volume, you're fine. It's just a really, really inefficient way of doing it.

Doc.

[Brokeass_baller]

That's exactly what I was hoping to hear.

It's inefficient, but free, and I'm cheap. Lol

[Brokeass_baller]

So far, no explodey. The one filled to 18oz is almost room temp now.

[shooter311]

Today I learned something! This is really cool (*insert guitar sting for the pun)

[Brokeass_baller]

Heck yeah man. The job we bought the pellets for is supposed to be finished today. If they haven't disposed of them by the time I go in, I'm going to fill a 12oz and a couple 9oz I have. I mean, why not? Lol

[Meleager7]

Tell me that those are Siphon Tanks.......!??

#LiquidCO2ForLife

[Brokeass_baller]

Nah. Just regular old pin valves with no internal tubing.

I do need to setup anti-siphon for a few of my older markers, but that isn't happening today. Lol

[zinger565]

Not the worst way to dispose of some dry ice!

Could also throw those in a bucket of water (or cooler of beer!) to stabilize them a bit faster.

[Marbo40k]

This is cool… not sure why I have never thought about doing this.
I rarely need CO2 anymore but I do have a bunch of tanks laying around. And dry ice is dirt cheap.

I’ll have to give this a try!

[Brokeass_baller]

It's certainly not the most efficient way of doing things. In the time it took me to smash down the next round of pellets into a funnelable snow, about 2oz of the previous fill would have gassed off. It probably took me 6 or 7 rounds of smashing and filling to get them up to about 18oz. Maybe 30 minutes each tank total time.

But it was free from the company, and I did it on the clock. So I benefited. Lol

[PlawB]

Er, 20 ounces of dry ice IS 20 ounces of room-temp liquid CO2.

It's like filling a 16 ounce glass with 16 (fluid) ounces of crushed ice, and wondering how much water you'll end up with.

As long as you filled the tank by weight, and not volume, you're fine. It's just a really, really inefficient way of doing it.

Doc.

Even though the caplets are taking up most of the room, there is still some air in there. What does that do to the pressure? Or, do most CO2 fills have some air in them anyways?

[Brokeass_baller]

I crushed the pellets into a snow and funneled them into the top of the tanks. CO2 is heavier than air, so I would imagine between the fine powder CO2 and the gaseous CO2 that boiled off as I was smashing the next round, all of the air was likely pushed out.

[Brokeass_baller]

You could see the cold gas "smoking" out the top and down around the tanks.

[Brokeass_baller]

Well it's been a few days and nothing's burst or ruptured. I even used one yesterday to troubleshoot an Illustrator clone of mine.

I'd call it a success.

[DocsMachine]

Even though the caplets are taking up most of the room, there is still some air in there. What does that do to the pressure? Or, do most CO2 fills have some air in them anyways?

-Yes, ALL CO2 tanks have "air" in there- that is, if the tank is "full" of liquid, yes, there's still a "bubble" of gas, to give it room to expand and contract. Had Broke filled the tank to physical capacity and then slapped the valve in place, the burst disc would have blown in short order. Had it warmed up too fast, it's not impossible the tank itself could have ruptured.

That's why I said to be sure to fill the tank by weight, not by volume. And it doesn't matter if he filled it with 20 ounces of gas, liquid or solid dry ice- 20 ounces of each is still 20 ounces.

Doc.

On this subject: One of my most favorite, ever, YouTubes.

Doc.

[Brokeass_baller]

Doc back in with the science. Much appreciated.

[Tarsun2]

i used to put hot water in a 2L soda bottle with dry ice.
its LOUD. so loud.

it would also turn the bottle inside out.

i can imagine its hyper dangerous though and probably not a smart idea.

[Brokeass_baller]

To be fair though, you're comparing filling a vessel rated to handle high pressure to that of a plastic vessel with which you intentionally over pressurized for explodey amusement.

[Tarsun2]

the soda bottle thing is hyper dangerous, not the paintball tank.

[Brokeass_baller]

I haven't had any issues with these. No burst discs bursting, no nothing. Used one recently to troubleshoot two Tippmanns and an Illustrator clone.