I have been using an active system (cmep) for over three years now. I am seeing talk about how much better passive systems can be (not just in cleanliness but also in recovery speeds) but it seems to me you have to have the proper chilling and tank system.
Is there a temperature threshold at which a passive system becomes more efficient than the active set-up?
Having the proper hosing and cooling on your recovery/phase change is extremely important. You can get away with not having to cool your tank with so much energy, by using some form of heat exchange (condensing coil, tube and shell, whatever) to eat up that energy. But, you would still need to keep your tank extremely cold.
If you have a decent chiller, you can use that to keep cold and use a coil. If you have a smaller tank steady access to dry ice and at a reasonable rate, it won’t be too hard.
It’s not as easy with a carbon tank, easier done with two, but then you’re restricted to the opening on the valves and they don’t last long anyway. Having a SS tank with the appropriate valves and guages will help make it much easier.
How long do carbon tanks last before you gotta ditch 'em
A got a year out of mine before the valves started leaking, but I turn my tank upside down to run/ flood, they also rust on the inside after awhile
6 month’s to a year. I’ve broken the handles and valves on them in far less time though, from the cold
fuck mine are hitting a year in September. time to flood one tank, distill it to a new one and scrap these two
Mine lasted 5 months before the valves started to leak.
@all how many times do you guys use them? I use mine once twice a month. … I store mine outside under my porch. They’ve gone thru new england weather… I dont have a detector but I have a spray bottle. I’ll spray the valves and check for leaks
Appreciate the reply Dred. You seem to be pretty active on this forum and I think that is pretty admirable. I have a 100# single jacketed recovery tank from BVV hooked up to my chiller. Chiller goes to the coil and single jacket is pulled to vuccum.
Currently I have a 1/4" stainless hose to a stainless coil in ice water before the recovery tank. My thoughts were to change this to an alcohol dry ice bath for the passive system. Obviously increasing the diameter of these will be needed for a full change. My concern is the cost of dry ice. That was the whole reason I switch to a chiller because I was just burning cash with all the dry ice I was using in my dewax column.
I can easily test this out but I just didnt know if there was a “common” temperature threshold I should shoot for that makes passive effecient.
Also, pumps tend to pull a lot of water that needs to be dried out with filters and such. Is this less or about the same with passive?
How are you guys breaking your tanks so fast??
people tend to over tighten the valves.
I think it’s more of trying to open close them when they are frozen.