German Brewing

Another thought. You could use dry ice + acetone. Should be able to get a nice, frosty -108F combining the two, and both are readily available at local stores. You should be able to reuse the acetone after the dry ice sublimates and just buy new dry ice for brew day.[/quote]


I tried this and holy shit it is awesome. I was reading temps like -50 F in the solution. The water was flowing ice cold. $30 for 2 gallons of acetone and $2 a pound for dry ice . Acetone is not corrosive or so I read. Im doing this every time now!

Huh.... how much dry ice did you use? Mind giving me some more data? Chiller type, input temp, output temp, volume?

Could one use ethanol instead of acetone? If it leaks then it's just ethanol, and you can use it as a sanitizer.

70/30 acetone to dry ice is what chemists recommend. I tried it with acetone and with 190 proof moonshine and both worked. I started with a simple experiment before I went nuts. If you take some crushed dry iceand slowly add acetone or ethanol and slowly add dry ice chips the temp goes way down in the solution. I will use this by submerging my pre-chiller in a two gallon steel bucket filled with acetone. I will then turn on the water flow to the prechiller and start to add dry ice chips until the water that is exiting the pre-chiller is as close to 32 as I can get without freezing the water in the lines. With regular liquid ice water, and even if I add salt, I can only get the wort down to 55 degrees F.

I did this on a small scale last night with a 2 foot section of copper that I wound into a coil. I plugged the water flow into the tiny coil and found that the water exiting the coil was super cold(just above 32 degrees F). The temp inside the dry ice bath reached -50F! Remember I was using a very small amount of dry ice chips and only 2 feet of copper. Imagine when I dunk the 25 foot chiller in 2 gallons of acetone and 5 lbs of dry ice on hand. I will just have to monitor the situation so nothing freezes.

I want to do another experiment when I document temperatures as I add the dry ice to get some consistency.



How the hell do I post pictures on this site?

upload to imgur and then link is what i do

I bring it down to near supply water temperature by recirculating slowly through my HE. Then I switch via a 3 way valve for the wort to run through a Cornelius Max 310 chiller into the fermenter. This gives me 45/50l of wort at 5 Celsius

I did more experiments last night and found freezing to be a problem for my pre chiller. I was unable to maintain a constant temp. I am going to experiment with dry ice, ethanol and ethylene glycol (antifreeze) tonight.

I'm interested to hear more.

Acetone/dry ice is common in the lab for doing reactions at sub zero temperatures however your not trying to bring your beer to 30 below. Low temperature does not equal thermal capacity and I would venture to say that a pound of carbon dioxide ice would not remove as much heat as a few pounds of ice. Circulating super cold fluid through a chiller will just cause the wort to freeze on it and that accumuled layer of ice around it will impede thermal transfer. Why mess around with highly flammable solvents when a bucket of ice water will do the job cheaper? Also imagine your beer, or your kitchen floor, if a fitting leaks acetone.