CO2 for Rez Cooling and Enrichment?

I am an offroad enthusiast, so I was filling up some tires this weekend with a CO2 tank on the trail. The air line and tank get very very cold when you use them. Yet not very much CO2 is really used either to get it cold. A short burst is enough to almost freeze a plastic line.

So could this be utilized to cool a res? More specifically, could you utilize the natural lower temps of CO2 to lower resevoirs temps AND benefit from CO2 enrichment as well? What about just running some copper tubes through the res and on a simple timer, releasing a few seconds of CO2? Would this use up the CO2 tank real quick? Obviously I am not expecting the same CO2 enrichment results like if you seeped it in with a timer and regulator, and I am probably dreaming, but since I am a tinkerer and love making stuff...think this is possible?

I just need a regulator, otherwise I have my CO2 enrichment stuff, so it would be nice to be able to use it for dual reasons. Do you guys think that even seeping CO2 slowly out of the reg and through copper pipes in the res would cool anything? Does heating up CO2 get rid of it or degrade it? I am assuming it does not since we raise grow room tempatures when we use CO2.

Thanks.

PV=nrT.

It's the gas law. As you depressurize CO2 it's going to become colder... But it doesn't degrade the CO2. I mean, I suppose if you had really good control you could do a bubbler thing... but you know some people use dry ice in a cooler with a hole or 2 poked in the top for CO2 enrichment, and it's reasonably inexpensive.

I don't know how great the extra CO2 is for roots. Someone more into hydro would be able to answer that... My hydro experience has been DYI flood and drain... haw haw.

Hm. You get me thinking... If you want to do tank CO2 enrichment, and use the decompression as sort of a heat remover for the res, maybe you could run the output from the tank through a copper coil not INTO the water but THROUGH the water.

Bubble CO2 through water and you get carbonic acid. Keep em separate. Also the best way to go would be to release the pressure into the coil, have a very tiny hole to release the gas over time onto the plants. Put it into the coil in one blast for the greatest effect. FYI thats how air conditioners work but they have a condenser to compress the gas again so its a cycle....you got a cold and hot side. You really dont need a regulator just a solenoid on a timer as long as the pipe can hold the pressure of the bottle.

I know that pic came out crappy but I was trying to draw the copper coil being submerged, but with the outlet into the air rather than into the water.

yeah I didnt meant to ACTUALLY bubble the CO2 into the res. I want to have the CO2 tank and run the CO2 in through some copper tubes THROUGH the res and then out the otherside, where the CO2 would be released into the room and enrich the plants on a specific time schedule (I have a CO2 controller). I am hoping there is enough cooling by just having the CO2 travel through 2 copper pipes submerged in the resevoir water.

I am only thinking about this because I am doing CO2 and I need to cool my res, and I figured this might be a way to kill 2 birds with 1 stone.

I am going to play around today and see how much CO2 needs to be released for the hose (or a copper tube) to get cold. I also was thinking that since the actual CO2 tank also gets really cold, that I could put my hydro resevoir into a larger resevoir and then I could just stick the CO2 tank right in there with it for further cooling.

PS. Like your picture Stinky, thats what I was talking about. I dont want CO2 inside the actual water, cause yes I am aware of carbonic acid. I already have air pumps for bubbles.

I like this idea. Let us know how well it works!

your regulater has an electronic silinoid be careful putting the bottle in the res. but i think it may work to some extent can't hurt at least. The copper tubing would be safer I think.

Oh wait I just thought of something:

Hydro res pH=5.5
Guess what, you're going to get copper dissolving off the tube into the water.
Excess copper=multinutrient lockout=dead plants.
You have to use stainless.

It sounds like a good idea, but just remember any metallic elements can sometimes be a potential problem weather it is an ionic or chemical change with the nutes in the res. And for anyone's personal info, roots like o2 and leaves CO2, but I think that it was figured out along the thread.
Adieu

do not use copper for tubing , some effects with the co2. Roots do not absorb co2 so thats out.
NOw putting the co2 in the room at given levels 1500 ppm works great.
Gas's going to a lower pressure usualy get cold.
Now when venting in to the room its best to use a sub blower to get it all over and vertical fans to get it off the floor. Note any leaks at the door levels , with out a good seal it just flows out a a very good rate.
See pictures in my gallery, for solonide and wiring

Deffinatly do NOT put copper in you tank! You WILL KILL your plants!

Quote:

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Originally Posted by oldsanclem

do not ......
See pictures in my gallery, for solonide and wiring

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Hey SanClem!, :)

How you doing buddy?

Hey man, I just wanted to give you a cookie for your drawing.
Not that much people actually spend the time to do stuff like that.

And another cookie goes to StinkyAttic.

:)

Interesting idea about cooling the rez.

I should go do what I'm praising, but if we know the heat capacity of CO2, and the one of water... and how much you'll be "purging", we can know if it'll work without building it.

IMO, it's a great idea. But I think you'll have to "purge" many times to get a significant decrease in temps.
But hey man, really good idea and kudos! ;)

Quote:

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Originally Posted by turtle420

if we know the heat capacity of CO2, and the one of water... and how much you'll be "purging", we can know if it'll work without building it.

....... But I think you'll have to "purge" many times to get a significant decrease in temps.

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Thanks for the cookie, yum.

The heat capacity of water is one of the most amazing properties of any chemical compound.

It's really high.

The heat capacity of CO2 is MUCH MUCH lower, so yeah, you're going to have to do a lot of purging to get it that much cooler, but every little bit counts and free cooling is better than none at all.

Exactly stinky. I figured every little bit cant hurt. I forgot to mention that I had figured copper or another metal would hurt the plant, so essentially I am going with the thinking that you could have the reservoir sitting in some other water around the reservoir (or find something that will carry the CO2 through the actual plant reservoir and not harm them).

But are you guys saying that if I just do a constant low seep (that would get exhausted every hour or so) that it wouldn't cool a tube of some sort going through the water at all? I mean, obviously when you purge it fast it cools the most...but wouldn't it still cool at a slower rate?

Also, I would never put my regulator in water. What I was saying was I could let my CO2 tank sit half in water that then surounded the reservoir water. No contamination. I havent used much CO2 so I dont know about whether its possible to let out a nice big burst of CO2 every so often, get my PPM, and hopefully do some cooling on the way out of the tank.

Low seep will work more efficiently, take a propane forklift for instance. After its been running for a bit the tank will be cold. Its a slow depressurization...increase the flow until you are satisfied with the temp reduction.