How to use my brazed plate heat exchanger??


Hey friends!

I’ve got this lovely Alfa laval Ac-70x-62m brazed plate heat exchanger. Snagged it for a “cool” $150 and it looks like it’s barely ever seen use.

I was thinking about making a little falling film evaporator (I hate my rotavap) for ethanol, and was curious if anyone had used these brazed plates before.

My first and easiest thought was just to use cold water in and out and call it a day. But I realized it’s built for refrigerants, and was curious if there’s a more self contained setup that might be worth building? Maybe dissasembling an old freezer or something?

I have the capacity to build a co2 expansion system for it, but it’s wayyyy overkill for my smaller needs at the moment.

Anyone got any tips?




Things get hot so make sure you dont cheap out on hose fittings valves and hoses/pipes. Been seeing some of the brightest “engineers” use pvc on their water lines only to have them blow out on the first day



Its got weld on fittings and I have some nice insulated hose :slight_smile:

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Have you done any load calcs to see how many btu of cooling capacity you might need? Would be interesting to see a cheap 240v 2 ton window AC modified to use that exchanger as the evaporator coil.

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Not much BTUs, probably want to evap 4L/h of ethanol?



Back in high school I chopped up a few window AC units to make subzero coolant systems for over clocking pc’s. You can get a simple piercing valve. Pump out the refrigerant. Chop the evap coil off the ac braze inline your exchanger there and fill your system back up. You should be pretty close to the same volume but put a guage on it to verify you have the correct amount of freon to refill the system after a leakdown test



4l an hour? Go big man lol

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Interesting… I’m pretty much just wanting to be able to plug in my heater, plug in my cooler, and call it a day. While not dealing with the wildly annoying stuff about a rotovap. Sound like that might work perfectly.



Well I just need something around here to evaporate off my stuff after winterizing, plus something to run 1-2lb test batches before throwing the stuff in the oven.



are you building a pot still? what will you use to evap the etoh from the tincture?

***sorry i see you said “mini ffe”

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put vapor in one port, and counterflow water in the other side.
liquid ethanol should come out.



^^ This. Or chiller fluid instead of water.
Plate type exchangers are ideal for condensers.



Is there any concern with the brazing interacting with the gin like the problems with copper? Or is this just for proofing?