Liquid CO2?

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
All CO2 tank fills are in fact liquid, just like propane. I know it's confusing because you open the valve and you get gas. That's because it boils as soon as you lower the head space pressure. Science is awesome.
 
Having liquid CO2 is probably not going to be practicable for home use. Basically to have it be a liquid you need a low enough temperature and a high enough pressure, something very roughly iirc like -150C and 200psig. So that means insulated tanks for one. Then if you drop the pressure too low, it turns solid (dry ice), so you wouldn't be able to 'pour' it for example.
 
Are you wondering where to get it filled locally? Common places most of us use: gas distributors (Airgas, Matheson), welding shops, fire extinguisher shops, homebrew shops, beverage supply shops.
 
porcupine73 said:
Having liquid CO2 is probably not going to be practicable for home use. Basically to have it be a liquid you need a low enough temperature and a high enough pressure, something very roughly iirc like -150C and 200psig. So that means insulated tanks for one. Then if you drop the pressure too low, it turns solid (dry ice), so you wouldn't be able to 'pour' it for example.
Click to expand...

Um, no. If it's in an inspected CO2 tank (the only legal way to get it in the US) it'll boil off to maintain a high enough pressure to remain in the liquid form. No insulation required. As Bobby pointed out, same deal as propane. If you want actual liquid CO2 to come out, you can get a tank with a dip tube. But please don't mess around with that unless you have the proper training.
 
Oh ok I didn't know you could have it be liquid at room temps, but yes I see it says above maybe 840psig at room temp it will be liquid too.
 
Bobby_M said:
What do you need liquid CO2 to come out of the tank for?
Click to expand...
It's actually not for homebrewing beer -- I just saw this forum and you folks seemed to be quite knowledgeable. :)

It's another food-related project I'm doing with a friend. Keeping the idea secret for now.

I just needed to know how to dispense liquid CO2 into a system. :eek:
 
Well if you get a CO2 tank with a dip tube, you can certainly do it. But cryogenic liquids, especially those under high pressure, can be pretty dangerous. If you're going to move forward do a lot of reading (handling liquid CO2 is much like handling liquid nitrogen) and make sure you have the proper hardware and some safety equipment. You might want a full face shield, not just glasses, and some waterproof insulated gloves. The high pressure hoses might be a bit pricey. If you ordered a smaller CO2 tank with no dip tube you can probably just invert it to get the liquid out.

Just please be careful!
 
zachattack said:
Well if you get a CO2 tank with a dip tube, you can certainly do it. But cryogenic liquids, especially those under high pressure, can be pretty dangerous. If you're going to move forward do a lot of reading (handling liquid CO2 is much like handling liquid nitrogen) and make sure you have the proper hardware and some safety equipment. You might want a full face shield, not just glasses, and some waterproof insulated gloves. The high pressure hoses might be a bit pricey. If you ordered a smaller CO2 tank with no dip tube you can probably just invert it to get the liquid out.

Just please be careful!
Click to expand...
How does a dip tube work?
I need to spray liquid co2 and another liquid together in a system to create a (frozen) mixture. Obviously the co2 will almost instantly turn to gas, and that's not a problem. And what do you mean by inverting it?
 
A dip tube is just a tube that goes from the tank valve all the way to the bottom of the tank. So when you open the valve, the tank empties from the bottom up instead of the top down. The liquid will be at the bottom of the tank, gas will be at the top so this way the gas pressure will force the liquid up the tube and out the valve. Its the same as in a keg of beer, you pressurize from the top and beer is forced through a dip tube to the faucet. You can flip the tank upside down as an alternative, but this adds another potential safety hazard. Some people here that use larger tanks to fill smaller tanks have mentioned building a frame/jig that securely holds the larger tank upside down to make sure it doesn't go anywhere during the transfer.
 
Thanat0s said:
How does a dip tube work?
I need to spray liquid co2 and another liquid together in a system to create a (frozen) mixture. Obviously the co2 will almost instantly turn to gas, and that's not a problem. And what do you mean by inverting it?
Click to expand...


Dip tube,,,Think like a straw in a cup of soda. You suck the soda through the straw thats end is very near the bottom of the cup. Essentially, a dip tube is going to work the same way, but instead of creating negative pressure at the outlest end of the straw, you would create positive pressure (more pressure than is at the open end of the straw) inside the cup, forcing the liquid out. This is how kegs work.

In the absence of a dip tube, by inverting (turning upside down) the container of co2, the the liquid co2 would be able to exit through the top of the container (which is now the bottom since you turned it upside down). Gravity keeps the liquid co2 in the bottom of the tank when it is upright (because liquid co2 is more dense "heavier" than co2 in a gas state), with a layer of gaseous co2 seperating the liquid co2 from the valve. Turning the container upside down will put the valve at the bottom of the tank, thereby exposing it to liquid co2. I would be very careful with this, as you can "freeze" the valve open and end up emptying the tank with possibly spectacular (but not necessarily good) side effects.

BTW, whatever liquid you are combining with the co2 is likely to be frozen as a result of what you describe. When the co2 converts to a gas from liquid, it is going to absorb heat energy, this absorbsion is going to be quite pronounced. Are you thinking about making a slushy machine with this?

Don't take this the wrong way, but I would strongly advise you to read up a little on thermodynamics in relation to liquid to gas conversion. By the wording of your questions, it sounds like there may be a couple of voids in your knowlege. You run a very high risk of injury if you are not careful.
 
wolfstar said:
Dip tube,,,Think like a straw in a cup of soda. You suck the soda through the straw thats end is very near the bottom of the cup. Essentially, a dip tube is going to work the same way, but instead of creating negative pressure at the outlest end of the straw, you would create positive pressure (more pressure than is at the open end of the straw) inside the cup, forcing the liquid out. This is how kegs work.

In the absence of a dip tube, by inverting (turning upside down) the container of co2, the the liquid co2 would be able to exit through the top of the container (which is now the bottom since you turned it upside down). Gravity keeps the liquid co2 in the bottom of the tank when it is upright (because liquid co2 is more dense "heavier" than co2 in a gas state), with a layer of gaseous co2 seperating the liquid co2 from the valve. Turning the container upside down will put the valve at the bottom of the tank, thereby exposing it to liquid co2. I would be very careful with this, as you can "freeze" the valve open and end up emptying the tank with possibly spectacular (but not necessarily good) side effects.

BTW, whatever liquid you are combining with the co2 is likely to be frozen as a result of what you describe. When the co2 converts to a gas from liquid, it is going to absorb heat energy, this absorbsion is going to be quite pronounced. Are you thinking about making a slushy machine with this?

Don't take this the wrong way, but I would strongly advise you to read up a little on thermodynamics in relation to liquid to gas conversion. By the wording of your questions, it sounds like there may be a couple of voids in your knowlege. You run a very high risk of injury if you are not careful.
Click to expand...
Not exactly a slushy machine..... but similar.
What dangers would this process run? Because I have no problem with buying a tank with a dip tube to keep it safe. Other than inverting the tank, what about this would be dangerous?
You're correct, there are many holes in my knowledge of thermodynamics.
 
Thanat0s said:
Not exactly a slushy machine..... but similar.
What dangers would this process run? Because I have no problem with buying a tank with a dip tube to keep it safe. Other than inverting the tank, what about this would be dangerous?
You're correct, there are many holes in my knowledge of thermodynamics.
Click to expand...


You will have to VERY precisely control the release of the liquid co2.
If you are releasing the co2 into the atmosphere, you are going to have a very hard time keeping the orafice through which the co2 escapes clear of ice. When the co2 converts to gas, it is going to extract heat energy from everything around it, including the tube through which it came. This will form condensation on that part, then the condensate will ice up. Eventually, your co2 tank wll ice up as well, reducing pressure and efficiency.

Liquid co2 escaping too rapidly can create an overabundance of co2 in the air you are breating...in an enclosed space, this can be dangerous. without knowing the particulars of your plans, there could be other concerns too.

Realistcally, your idea does work in theory, but you will need to have a very high level of machining knowlege (or know someone that does) with access to a pretty decent machine shop to machine the part your liquid co2 would exit from. You would also need some sort of method to insulate the exit tube from condesation, etc.

Is this for a culinary application?
 
It is for a culinary application - very similar (almost exactly) to a slushy maker, but with a variation of application.
Can one not just buy piping online and connect them into one "mixing" container, and use regulators to control the flow of co2 and the liquid? What would need to be machined? And could one not leave a vent in the top of the final container to allow the co2 to escape safely without icing up the pipes too badly?
I can maybe get access to a machining shop (I think) but I'd rather make it myself.
 
If this is strictly for a culinary application, you might find much more friendly dynamics from simply liquid nitrogen. That can be used in many food apps, such as making ice cream in mere minutes. You can get liquid nitrogen in food grade, medical grade, whatever you need. The main advantage there being it will be liquid at 1atm no problem, whereas co2 is far more tricky.
 
porcupine73 said:
If this is strictly for a culinary application, you might find much more friendly dynamics from simply liquid nitrogen. That can be used in many food apps, such as making ice cream in mere minutes. You can get liquid nitrogen in food grade, medical grade, whatever you need. The main advantage there being it will be liquid at 1atm no problem, whereas co2 is far more tricky.
Click to expand...
Liquid CO2 is the key ingredient ;P
 
Thanat0s said:
Liquid CO2 is the key ingredient ;P
Click to expand...

Liquid CO2 does not exist at standard pressure. I have had tanks (paintball prior to brewing) with on/off valves. When opened, gas and "snowflakes" come out, but no liquid. I also worked in a chemistry lab and can't explain the joy of pouring liquid nitrogen on people.

You are going to have to give a little more background (keep all the secrets you'd like) if you want any reasonable advice from anyone on here...aside from BE CAREFUL - SERIOUSLY!
 
Thanat0s said:
It is for a culinary application - very similar (almost exactly) to a slushy maker, but with a variation of application.
Can one not just buy piping online and connect them into one "mixing" container, and use regulators to control the flow of co2 and the liquid? What would need to be machined? And could one not leave a vent in the top of the final container to allow the co2 to escape safely without icing up the pipes too badly?
I can maybe get access to a machining shop (I think) but I'd rather make it myself.
Click to expand...

Soda fountains do essentially what you are describing.

When you here that "pshh...pshh...pshhh" sound at the soda fountain that is part of the process.

uncarbonated water+co2+soda syrup to make your favorite carbonated drink.

These do have a vent, but it is controlled.

This would be a pretty complicated item for someone to DIY, but not impossible i suppose.
 
freisste said:
Liquid CO2 does not exist at standard pressure. I have had tanks (paintball prior to brewing) with on/off valves. When opened, gas and "snowflakes" come out, but no liquid. I also worked in a chemistry lab and can't explain the joy of pouring liquid nitrogen on people.

You are going to have to give a little more background (keep all the secrets you'd like) if you want any reasonable advice from anyone on here...aside from BE CAREFUL - SERIOUSLY!
Click to expand...
Just treat it as if I was creating a slushy maker. It's almost exactly the same. :)
I was going to use a dip tube to have the pressurized liquid co2 come out.
 
wolfstar said:
Soda fountains do essentially what you are describing.

When you here that "pshh...pshh...pshhh" sound at the soda fountain that is part of the process.

uncarbonated water+co2+soda syrup to make your favorite carbonated drink.

These do have a vent, but it is controlled.

This would be a pretty complicated item for someone to DIY, but not impossible i suppose.
Click to expand...
Why would it be complicated?
I'm envisioning:
O < co2
| < regulator/valve
>---O (mixing container)
| < regulator/valve
O < liquid
 
Thanat0s said:
Just treat it as if I was creating a slushy maker. It's almost exactly the same. :)
I was going to use a dip tube to have the pressurized liquid co2 come out.
Click to expand...

You're not getting it. Liquid CO2 won't come out. Gaseous CO2 and solid CO2 will come out and the solid will be a VERY small amount...and will almost instantly sublime (its like evaporating, but it is solid to gas instead of liquid I gas).

It only goes from one tank to another as a liquid because both tanks are pressurized.

Also, someone said that soda fountains are water, CO2, and syrup, but I'm pretty sure they are carbonated water and syrup...
 
freisste said:
You're not getting it. Liquid CO2 won't come out. Gaseous CO2 and solid CO2 will come out and the solid will be a VERY small amount...and will almost instantly sublime (its like evaporating, but it is solid to gas instead of liquid I gas).

It only goes from one tank to another as a liquid because both tanks are pressurized.

Also, someone said that soda fountains are water, CO2, and syrup, but I'm pretty sure they are carbonated water and syrup...
Click to expand...

Zachattack disagrees.
If you use a dip tube, the gaseous CO2 would push the liquid up.
 
Thanat0s said:
Zachattack disagrees.
If you use a dip tube, the gaseous CO2 would push the liquid up.
Click to expand...

Yeah, I understand that liquid within the container would be forced out. But when it hits the atmosphere (unpressurized) it would come out of the tank as a mixture of mostly gas and a small amount of solid CO2 (dry ice). Nearly immediately it will sublime to a gaseous state.

This is driving me nuts. WTF are you trying to do? If you aren't on the verge of patenting something, give up the details before I pull my hair out...
 
freisste said:
This is driving me nuts. WTF are you trying to do? If you aren't on the verge of patenting something, give up the details before I pull my hair out...
Click to expand...
It's a critical component to his free energy machine.
 
Nonyaz said:
It's a critical component to his free energy machine.
Click to expand...
PRECISELY.
It conjures more liquid co2 using my patented egg-aluminum mixture.
Seriously though - it's basically a slushy maker with different ingredients, lol :) the co2 application is precisely the same.
Also, the tubing would be rather short - how fast would it turn to gas? I only need it in liquid state for just about half a second.
 
Thanat0s said:
PRECISELY.
It conjures more liquid co2 using my patented egg-aluminum mixture.
Seriously though - it's basically a slushy maker with different ingredients, lol :) the co2 application is precisely the same.
Also, the tubing would be rather short - how fast would it turn to gas? I only need it in liquid state for just about half a second.
Click to expand...

Sounds like a fun physics experiment, but I would guess it is in the liquid state for roughly zero seconds. No time. If it is at atmospheric pressure, it is NOT liquid. There may be a small fraction of a second while the liquid is still within a pressurized area of the gas stream leaving a nozzle, but again, it would be an extremely short period of time. Sorry if I am crushing a dream. As was mentioned earlier, you could try liquid nitrogen. It can exist at atmospheric pressure as long as it is cold, which can be a few minutes in a jar (although it is boiling that whole time).
 
Liquid CO2 does not exist at standard pressure
Click to expand...

Not true. Although I also have experienced the dry-ice phenomena mentioned in this thread, it's my understanding that breweries and big users of CO2 take delivery not in pressurized bottles, but as liquid CO2, very similar to the way liquid nitrogen is delivered. It may be under a small amount of pressure; I'm not sure. And then, since they use the CO2 quickly, they actually have to have heaters to keep dry ice from forming.
 
freisste said:
Sounds like a fun physics experiment, but I would guess it is in the liquid state for roughly zero seconds. No time. If it is at atmospheric pressure, it is NOT liquid. There may be a small fraction of a second while the liquid is still within a pressurized area of the gas stream leaving a nozzle, but again, it would be an extremely short period of time. Sorry if I am crushing a dream. As was mentioned earlier, you could try liquid nitrogen. It can exist at atmospheric pressure as long as it is cold, which can be a few minutes in a jar (although it is boiling that whole time).
Click to expand...
I did fail my thermodynamics course, but that aside, if the goal is to make said ingredients cold, and assuming the liquid co2 does all its energy absorption at the point of pressure change, as long as you had the output nozzle inside your mixing container, you'd surely make it colder. Likely have a huge ice clump around the outlet in short order, but stuff will more or less be colder than when you started :)
 
Nonyaz said:
I did fail my thermodynamics course, but that aside, if the goal is to make said ingredients cold, and assuming the liquid co2 does all its energy absorption at the point of pressure change, as long as you had the output nozzle inside your mixing container, you'd surely make it colder. Likely have a huge ice clump around the outlet in short order, but stuff will more or less be colder than when you started :)
Click to expand...
Wooo! Ice clumps aren't a problem (I can easily take care of them), and yes, the energy absorption should account for that.
Now to build the mixing container... hmm
 
Nonyaz said:
I did fail my thermodynamics course, but that aside, if the goal is to make said ingredients cold, and assuming the liquid co2 does all its energy absorption at the point of pressure change, as long as you had the output nozzle inside your mixing container, you'd surely make it colder. Likely have a huge ice clump around the outlet in short order, but stuff will more or less be colder than when you started :)
Click to expand...

It will absolutely make things colder. Maybe I misunderstood what OP was trying to do. Pressurized CO2, which is a combination of liquid and gas, is likely at room temperature. When the pressure is released, the temperature drops very rapidly. If all you are trying to do is make something cold, this can be accomplished by releasing the pressure.

If you are looking for liquid CO2 at atmospheric pressure, go to your local unicorn farm. Santa Clause feeds unicorns and the Easter Bunny liquid CO2 and cheese from the moon.
 
BetterSense said:
Not true. Although I also have experienced the dry-ice phenomena mentioned in this thread, it's my understanding that breweries and big users of CO2 take delivery not in pressurized bottles, but as liquid CO2, very similar to the way liquid nitrogen is delivered. It may be under a small amount of pressure; I'm not sure. And then, since they use the CO2 quickly, they actually have to have heaters to keep dry ice from forming.
Click to expand...

It is true. Your understanding is incorrect.
 
Thanat0s said:
Wooo! Ice clumps aren't a problem (I can easily take care of them), and yes, the energy absorption should account for that.
Now to build the mixing container... hmm
Click to expand...

All you want to do is make things cold? There are a million and six ways to do that! I thought you actually needed CO2 in a LIQUID state! You CAN cool things with pressurized CO2, you just can't have CO2 liquid at atmospheric pressure. Sorry if I caused confusion.

I'd still love to know what the hell you're doing...
 
freisste said:
All you want to do is make things cold? There are a million and six ways to do that! I thought you actually needed CO2 in a LIQUID state! You CAN cool things with pressurized CO2, you just can't have CO2 liquid at atmospheric pressure. Sorry if I caused confusion.

I'd still love to know what the hell you're doing...
Click to expand...
Maybe he thinks it will carbonate it?
 

Similar threads

Draft Master Flash
15 lb Co2 tank overfilled?
Replies
17
Views
502
Draft Master Flash
Draft Master Flash
agentbud
CO2 Transfer Question
Replies
14
Views
410
Wigglebutts Brewery
Wigglebutts Brewery
iandanielursino
Anyone ever thought of trying to use CO2 from the same batch to bottle that batch?
Replies
13
Views
527
iandanielursino
iandanielursino
C
Cold Crash / Force Carb Temp and Pressure Vs Serving Temp andPressure
Replies
6
Views
790
Corey22
C
Clint Yeastwood
Question for Nerds
Replies
10
Views
600
Clint Yeastwood
Clint Yeastwood

Latest posts

Back
Top