[Itsgotatail]

I'm a little worried about getting my recovery tank that cold. I think I Read that this model maybe had some issues with the valves getting brittle. Although I suppose I could just use external valves that I don't let get that cold. What about a counterflow heat exchanger coming out of my recovery tank as well as another heat exchanger leaving my pump going into the recovery tank to replace my coil chiller that currently also just sits in ice. Run both heat exchangers with a shared circulating dry ice/alcohol bath? Maybe I could even chill the recovery tank with the same shared coolant? With LN2 I'm worried about getting things too cold. Maybe I could buy heat exhangers that would also work with a refrigerant if I get that AC unit working again? Is that possible? And how big of heat exchangers do I need. I suppose I'd need bigger ones for dry ice/alcohol than for LN2.

As far as that blowout last time, YEAH, that was a good staartle! I'll definitely be building some failsafe mechanisms in now. As well as the bypass you mentioned, I have another 50lb recovery tank that I can keep under vaccum and chilled, maybe even attached at two or more points in the loop, with separate valves so that I can recover passively from different isolated parts of the system if something goes awry.

[Jslump510]

I Bottom fill a 6x48 to different levels of tane depending on material column size imma push threw, close it off at bottom and pull recovery off top the column with a cmep 6000 while throttling vacuum with a 24 inch Bfe base to chill my tane kinda rapidly then when psi gets to 3 ish on the 6x48 i dump it threw bottom and use the head pressure from solvent tank to push out the top of the 6x48 inch solvent column, you can pull the ran material back to the 6x48 as well recool it and push threw a filter stack. when i do this it feels creative lol

[Itsgotatail]

Would a plate style heat exchanger like this work? They seem to come in any size imaginable. Ports look workable without any welding. Just trying to figure out how big of ones I'd need.

https://www.amazon.com/gp/aw/d/B00XT...xRL&ref=plSrch


A circulating alcohol glycol coolant seems like a winner for me. I could chill the reservoir with dry ice now and then use that AC unit to chill it later...or just have the refrigerant run through the heat exchanger, if that's possible.

[Gray Wolf]

Originally Posted by Itsgotatail

Would a plate style heat exchanger like this work? They seem to come in any size imaginable. Ports look workable without any welding. Just trying to figure out how big of ones I'd need.

https://www.amazon.com/gp/aw/d/B00XT...xRL&ref=plSrch


A circulating alcohol glycol coolant seems like a winner for me. I could chill the reservoir with dry ice now and then use that AC unit to chill it later...or just have the refrigerant run through the heat exchanger, if that's possible.

Check the rated operating pressure. For LPG it needs to be 350psi minimum.

[Itsgotatail]

Yes, I wouldn't order anything without checking psi ratings beforehand. Do you have a preference for these plate style heat exchanger vs. the tube and shell style vs some other style that I'm not seeing out there? There doesn't seem to be a ton of material out there on heat exchangers for this application. I'm guessing I should just order the one with the most internal transfer surface area as I can afford. Many seem to be rated inBTUs but I wouldn't know how to calculate that.

[Gray Wolf]

Originally Posted by Itsgotatail

Yes, I wouldn't order anything without checking psi ratings beforehand. Do you have a preference for these plate style heat exchanger vs. the tube and shell style vs some other style that I'm not seeing out there? There doesn't seem to be a ton of material out there on heat exchangers for this application. I'm guessing I should just order the one with the most internal transfer surface area as I can afford. Many seem to be rated inBTUs but I wouldn't know how to calculate that.

A counterflow or a tube and shell will have a higher pressure rating than a plate type. A simple 50' coil of 1/2" 304SS tubing will also have a higher pressure rating.

The way I calculate gross btu rejection capacity, is start with the R-value of the material used and convert that to K-value by dividing (1) one by the R-value (1/R=K). K value is the btu's transfered per square inch, per degree of delta temperature across it, per unit time.