Liquid CO2?

[Thanat0s]

Maybe he thinks it will carbonate it?

Not just think - I've read up on stuff like this done before.
They used LIQUID CO2 to do it, in a similar fashion - spraying liquid CO2 at ice cream mixture, in their case. I'm not doing it with ice cream but identical application.
How did they do it, then? The process I described is what they used - liquid CO2 pumped at another liquid into a chamber.

 

[Nonyaz]

Not just think - I've read up on stuff like this done before.
They used LIQUID CO2 to do it, in a similar fashion - spraying liquid CO2 at ice cream mixture, in their case. I'm not doing it with ice cream but identical application.
How did they do it, then? The process I described is what they used - liquid CO2 pumped at another liquid into a chamber.

I'm not saying it won't, seems dubious to me but then again I'm in school for electrical engineering not chemical

Speaking of, time to hit the sack, I'd wait till' morning for more knowledgeable people to chime in, good luck to you!

 

[Thanat0s]

I'm not saying it won't, seems dubious to me but then again I'm in school for electrical engineering not chemical

Speaking of, time to hit the sack, I'd wait for morning for more knowledgeable people to chime in, good luck to you!

Thank you for your help!
Have a good night.

 

[freisste]

Not just think - I've read up on stuff like this done before.
They used LIQUID CO2 to do it, in a similar fashion - spraying liquid CO2 at ice cream mixture, in their case. I'm not doing it with ice cream but identical application.
How did they do it, then? The process I described is what they used - liquid CO2 pumped at another liquid into a chamber.

Get a tank, fill it with CO2, and position it near the stream of your other liquid (not ice cream or slushy).

Start a drip of your other liquid and open the valve on the CO2 tank. It will come out VERY cold and likely freeze your other liquid. (You would likely be better off angling the CO2 tank to blow out gas instead of liquid. Not because it would work much better, but because it would use your CO2 much more economically.)

I think it will work, I'M JUST SAYING IT WILL NOT BE LIQUID CO2!

 

[BetterSense]

It is true. Your understanding is incorrect.

http://www.nuco2.com/products/xactco2.html

So this company is a scam?

 

[Dolomieu]

http://dspace.mit.edu/handle/1721.1/35663

 

[Thanat0s]

Get a tank, fill it with CO2, and position it near the stream of your other liquid (not ice cream or slushy).

Start a drip of your other liquid and open the valve on the CO2 tank. It will come out VERY cold and likely freeze your other liquid. (You would likely be better off angling the CO2 tank to blow out gas instead of liquid. Not because it would work much better, but because it would use your CO2 much more economically.)

I think it will work, I'M JUST SAYING IT WILL NOT BE LIQUID CO2!

This is awesome. What do you mean by a "drip"? Will this process take a while?

 

[squeekybobo]

Reading this makes me want to go watch Breaking Bad...

 

[Thanat0s]

http://dspace.mit.edu/handle/1721.1/35663

Yeah!!!

 

[Thanat0s]

Reading this makes me want to go watch Breaking Bad...

Do it. I love that show.

 

[Dolomieu]

Op you should be looking at industry journals or something a little more substantial than a forum. Not that the people here arent well imformed, they are. BUT if this is something you are trying to design to profit from, maybe do your own work.

 

[freisste]

http://www.nuco2.com/products/xactco2.html

So this company is a scam?

What? No, they don't appear to be a scam. They appear to be a legit company and they have CO2 tanks. What is your point?

 

[Thanat0s]

Op you should be looking at industry journals or something a little more substantial than a forum. Not that the people hear arent well imformed, they are. BUT if this is something you are trying to design to profit from, maybe do your own work.

Yeah, I was originally trying to just ask about liquid CO2. But then I found out about the huge amount of insight this forum has!
Gonna see if anyone has any insight into that posted MIT project link thing.

 

[Dolomieu]

http://www3.imperial.ac.uk/people/e.muller/teaching/icecream

 

[LabRatBrewer]

Thanatos in Greek mythology is the personification of death. I'd not want to be the first to try his concoction.

 

[Thanat0s]

Thanatos in Greek mythology is the personification of death. I'd not want to be the first to try his concoction.

You're awesome for getting the name.
Dolomieu, that's awesome! I wonder if his process carbonates it like the MIT process.

 

[mattd2]

Why would it be complicated?
I'm envisioning:
O < co2
| < regulator/valve
>---O (mixing container)
| < regulator/valve
O < liquid

From what you have kind of drawn there it looks like you want to mix the co2 and liquid before the mixing container? If so I woul think that if the plan is to use the liquid CO2 to cool the liquid, what you have drawn there will not work. Firstly you state you have a regulator (this term would usually be applied to a pressure regulator in case like this), what you want is a metering valve to adjust the flow but to make sure you do not get a large pressure drop accross this and evaporate the liquid CO2 at this point you will need an oriface (read: small hole) at the point of injection - this was mentioed earlier.
Second you have the liquid coming into the mixing point, unless you can get the liquid up to the pressure of liquid CO2 at room temp (870ish PSI) all that will happen is you will push the liquid back with the CO2. I would think a venturi mixing could possibly work in this case.

Are you going forward with a prototype to develop into a comercial product or is this just some DIY hack you want to do.
If it is the first you really need to engage an engineer with experience in pressure equipment and food & beverage applications. When you do make sure you get them to sign a properly drafted non disclosure statement (for that you will probably also need to see a lawyer)
If it is the second, why they hell can't you just tell us what you are planning on doing so we can actually help

Lastly if you are trying to make a slushy machine with CO2, when apparently they already exist with N2 (I think you said they were available?) stop and think if making it out of CO2 makes actual sense - CO2 is more expensive to produce and harder to handle use.

 

[rajun50]

http://www.nuco2.com/products/xactco2.html

So this company is a scam?

That's liquid co2, yes. There is also liquid co2 in a 5lb co2 tank, and any other size co2 tank you see. The point is that it's only liquid co2 because it's in that pressurized tank. The vapor pressure of co2 at room temperature is over 800psi. You simply can't have liquid co2 at standard temperature and pressure. It will turn to gas immediately. I'm assuming you're thinking that the co2 tanks you use are filled with co2 gas, but that isn't the case. It's all liquid until the pressure drops (valve is opened), which causes the liquid to boil off into gas, which we use to carbonate our beer. That's also why you want to keep your co2 tank upright when connected to your regulator. If it were turned upside down, you'd end up with liquid co2 in your regulator, and then in your keg. Not good.

 

[Thanat0s]

From what you have kind of drawn there it looks like you want to mix the co2 and liquid before the mixing container? If so I woul think that if the plan is to use the liquid CO2 to cool the liquid, what you have drawn there will not work. Firstly you state you have a regulator (this term would usually be applied to a pressure regulator in case like this), what you want is a metering valve to adjust the flow but to make sure you do not get a large pressure drop accross this and evaporate the liquid CO2 at this point you will need an oriface (read: small hole) at the point of injection - this was mentioed earlier.
Second you have the liquid coming into the mixing point, unless you can get the liquid up to the pressure of liquid CO2 at room temp (870ish PSI) all that will happen is you will push the liquid back with the CO2. I would think a venturi mixing could possibly work in this case.

Are you going forward with a prototype to develop into a comercial product or is this just some DIY hack you want to do.
If it is the first you really need to engage an engineer with experience in pressure equipment and food & beverage applications. When you do make sure you get them to sign a properly drafted non disclosure statement (for that you will probably also need to see a lawyer)
If it is the second, why they hell can't you just tell us what you are planning on doing so we can actually help

Lastly if you are trying to make a slushy machine with CO2, when apparently they already exist with N2 (I think you said they were available?) stop and think if making it out of CO2 makes actual sense - CO2 is more expensive to produce and harder to handle use.

Well, I'm essentially going for some sort of carbonated sorbet. The MIT project that was posted has the same application - liquid CO2 being sprayed/mixed against the mixture to carbonate and freeze it.
How do I do it, then?

 

[freisste]

Well, I'm essentially going for some sort of carbonated sorbet. The MIT project that was posted has the same application - liquid CO2 being sprayed/mixed against the mixture to carbonate and freeze it.
How do I do it, then?

You may have just set a record for off-topic-edness.

Still not totally clear here, but you could mix liquid CO2 with liquid sorbet under high pressure. At these high pressures, the CO2 can be at equilibrium as a liquid. Then supercool the liquid to solidify the sorbet. At this point, the CO2 is dissolved in the liquid. As it melts, the CO2 would come out of equilibrium and make the sorbet appear to boil. I am not totally sure if it will work, but it is sound in theory. (I do know the same process is used with plastic and when heated to a softening point, the plastic bubbles up. Unfortunately, sorbet isn't particularly rigid and may be near its softening point at freezer temps. You may have to store it in especially cold freezers...like Dippin' Dots! Probably couldn't sell it in the supermarket, though, because it would likely soften on the way home.)

Good luck in your endeavors and be careful.

 

[Thanat0s]

You may have just set a record for off-topic-edness.

Still not totally clear here, but you could mix liquid CO2 with liquid sorbet under high pressure. At these high pressures, the CO2 can be at equilibrium as a liquid. Then supercool the liquid to solidify the sorbet. At this point, the CO2 is dissolved in the liquid. As it melts, the CO2 would come out of equilibrium and make the sorbet appear to boil. I am not totally sure if it will work, but it is sound in theory. (I do know the same process is used with plastic and when heated to a softening point, the plastic bubbles up. Unfortunately, sorbet isn't particularly rigid and may be near its softening point at freezer temps. You may have to store it in especially cold freezers...like Dippin' Dots! Probably couldn't sell it in the supermarket, though, because it would likely soften on the way home.)

Good luck in your endeavors and be careful.

You raise fair points!
Also, I was considering doing that with mixing them, but the only problem is that I would think that would use too much liquid CO2 at once. Go back 1-2 pages and read the MIT study on carbonated ice cream.

 

[Thanat0s]

Also, could I use a Venturi chamber to mix the liquids?

 

[freisste]

You raise fair points!
Also, I was considering doing that with mixing them, but the only problem is that I would think that would use too much liquid CO2 at once. Go back 1-2 pages and read the MIT study on carbonated ice cream.

I think it would use as much as you meter into the mixing chamber. I read the MIT thing last night, so I don't remember exactly what it said. I think a 1:1 ratio was optimal. Not sure if that was a mass ratio or volume ratio, but you should probably experiment to find the optimal point for your application. At any rate, you should be able to dictate the ratio in your system. It would be easy in a batch process. In a continuous process it would be more complicated but likely not impossible.

 

[freisste]

Also, could I use a Venturi chamber to mix the liquids?

Possibly, but keep in mind venturis rely on a low pressure area caused by movement of material. "Low pressure" is a relative term here as it will all have to be high pressure. I think you would be better off with a batch process where you added a certain amount of material to a mixing chamber, sealed the chamber, pressurized (maybe with an initial charge of CO2, but more economically with a mechanical press - almost like a hydraulic cylinder works), then forced liquid CO2 into the system before mixing. Then cool the entire chamber, release the pressure, and remove the carbonated block of frozen goodness.

That's my best off-hand idea, anyway. You are still probably better off with nitrogen. With nitrogen, you don't have to worry about the high pressure cylinders and you can pour little bits on yourself and coworkers. It freaks people out, but really isn't as dangerous as it seems. (Man I miss the days in the chemistry lab)

 

[Nonyaz]

Another concern is the pressure referenced in the mit article is 576 psi. I would be greatly worried about the pressure vessel becoming supercooled and having its elasticity drop to about the level of a saltine and shattering/exploding in a spectacular fashion. I would suggest you have an engineering firm design that part along with any fittings attached to it. That way you have a PE signing his name to a piece of equipment that he/she guarantees to operate in a specified temperature range/pressure.

 

[RobertRGeorge]

I'm very late to this conversation but I must say that while many people oftentimes want to be helpful if they can, this is a heck of a bad place to be getting detailed engineering consulting for the design of a device that seems to have the potential to be extremely lethal. Just my opinion.

 

[Thanat0s]

Possibly, but keep in mind venturis rely on a low pressure area caused by movement of material. "Low pressure" is a relative term here as it will all have to be high pressure. I think you would be better off with a batch process where you added a certain amount of material to a mixing chamber, sealed the chamber, pressurized (maybe with an initial charge of CO2, but more economically with a mechanical press - almost like a hydraulic cylinder works), then forced liquid CO2 into the system before mixing. Then cool the entire chamber, release the pressure, and remove the carbonated block of frozen goodness.

That's my best off-hand idea, anyway. You are still probably better off with nitrogen. With nitrogen, you don't have to worry about the high pressure cylinders and you can pour little bits on yourself and coworkers. It freaks people out, but really isn't as dangerous as it seems. (Man I miss the days in the chemistry lab)

I don't think I have the resources to create an intensely high pressure vessel to compress the mixture.
What do you mean by Venturis relying on low pressure? I just need to spray the liquids together to mix them.

 

[wolfstar]

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...

I said that. The soda fountain at your local fast food joint is hooked up to 4 things, tap water, a co2 tank, a bag of syrup (bag-in-the-box),and electricity.

The water is carbonated in the machine (but the water comes from a municipal supply line) , and is then mixed with the syrup right before it leaves the nozzle and enters your cup.

 

[freisste]

Hmm. I must have misunderstood how they worked. I always thought that they were carbonated water tanks, not CO2 tanks.

This isn't a first, I doubt it will be the last.

 

[wolfstar]

You may have just set a record for off-topic-edness.

Still not totally clear here, but you could mix liquid CO2 with liquid sorbet under high pressure. At these high pressures, the CO2 can be at equilibrium as a liquid. Then supercool the liquid to solidify the sorbet. At this point, the CO2 is dissolved in the liquid. As it melts, the CO2 would come out of equilibrium and make the sorbet appear to boil. I am not totally sure if it will work, but it is sound in theory. (I do know the same process is used with plastic and when heated to a softening point, the plastic bubbles up. Unfortunately, sorbet isn't particularly rigid and may be near its softening point at freezer temps. You may have to store it in especially cold freezers...like Dippin' Dots! Probably couldn't sell it in the supermarket, though, because it would likely soften on the way home.)

Good luck in your endeavors and be careful.

Good post...I would expect it to blow up like a frozen marshmallow under vaccum if he gets the co2 dissolved enough.

 

[Cambone]

Why do I feel like this thread is one elaborate troll?

 

[wolfstar]

I don't think I have the resources to create an intensely high pressure vessel to compress the mixture.
What do you mean by Venturis relying on low pressure? I just need to spray the liquids together to mix them.

You realise of course that the quantity of actual liquid co2 you will need for a palatable amount of carbonation is extremely small in relation to the quantity of your product. If you think about it, a 5 pound co2 tank is good for about 20 5 gallon kegs of beer, give or take a few depending on style and other factors.

You might be better off carbonating your mixture by traditional means while it is still liquid, then freezing it under pressure to keep the co2 in solution.

 

[BrewThruYou]

Get a samarai sword (Hanzo hopefully) and chop the co2 tank in half and pour out all that liquid co2 goodness from the bottom half.

 

[Thanat0s]

Hm. I don't think I have the resources to create a pressure vessel as described. I'd rather not do it in batches.
I suppose I'll go find an engineer for advice. If anyone has anything else to contribute, let me know!

 

[porcupine73]

Not sure if this helps, but there is information about there about using liquid co2 to do drycleaning. Obviously they have to keep the pressure high enough to prevent it from solidifying, but maybe you pick up one of those machines secondhand and modify it for your purposes?

 

[mattd2]

Well, I'm essentially going for some sort of carbonated sorbet. The MIT project that was posted has the same application - liquid CO2 being sprayed/mixed against the mixture to carbonate and freeze it.
How do I do it, then?

What is a carbonated sorbet?All I can image is a mess with bubbling slushy popping all over the place
As to how to do it, if you don't know how to do it yourself you need to find someone who can - either a professional proces engineer ($$$$$$$) or go to you local Universities engineering school and try and find some process engineering student (warning they could potentially know as much as you)

If I had to guess I would imagine it to look something like this (with controls to get the flowrate of the liquid to match what the CO2 is doing / CO2 flowrate fixed by designing the oriface appropriatly):

 

[Gabba]

Why do I feel like this thread is one elaborate troll?

Either a troll or an interesting obituary in the making

 

[Thanat0s]

I'm actually completely serious. But it would be an amazing obituary, I have to admit.
"MAN KILLED BY DELICIOUS DESSERT"
As for the above diagram, that's what I envisioned too, I just need to figure out the details of effectively combining the liquids.

 

[Thanat0s]

You might be better off carbonating your mixture by traditional means while it is still liquid, then freezing it under pressure to keep the co2 in solution.

Right, but would the carbonation be efficiently contained? That's my concern.

 

[Thanat0s]

I think part of the appeal to doing this with liquid co2 is the interesting mouth feel that it creates.