I wasn't sure whether to put this in the Beginner section or Technique, but since its mainly about technique I threw it here..but be warned it is definitely beginner in nature.
We are getting ready in the next few weeks to start playing around with out 100 gal still. This is a side project at this point in time, so the plan always was to 'learn on the job' as we are not trying to push any product out in the near future. I have read every book and website I could over the last 6 months to learn as much as I could, but now staring up at the still, its hard to figure out how to put that book knowledge into real life. I have a list of questions regarding proper usage of the still, if anyone could help answer some of these it would be greatly appreciated. Most of these questions have to do with temperatures.
My plan has been to make cuts based on temperature as we learn, and I have all the temperature ranges, but where specifically are we talking about the temperature? Is this in reference to the temp of the vapor as it leaves the kettle? The temp of the wash? Or somewhere else in the process?
Is there a target temperature to keep the mash at once we start boiling, or is it more of visual to keep everything flowing consistently?
We have 2 columns, a 4-plate and a 16-plate. For the dephlegmator, is there a temperature range I should be shooting for when controlling the flow of the cooling water? Our still manufacturer said most people want the cooling water temp on the dephlegmator to around 78C. Does this make sense?
For condensing column, we were recommended to have the distillate come out between 34-40C. Is this a good range?
After typing this out, I guess I'm really asking if the main things I should be looking for and paying attention to is the temps in the kettle, the dephs, and the condenser? And then make adjustments to keep those temps in range.
First get it out of your head that temperature corresponds to cuts. It may or may not, depends on how you run. Temperature is proportional to alcohol content and nothing else. There is also a pressure component, but it is a small effect, but don’t overlook it if what you are doing is high precision.
The boiler temperature gives you an idea of how much alcohol is in the boiler. The highest temperature the boiler will reach is the boiling point of water at your elevation. For me that was about 200 deg. The temperature will start lower depending on the % of alcohol and then raise during the run as the alcohol is depleted. Once it approaches the bp of water you know most of the alcohol is gone. The wash % will impact the starting bp, more alcohol, lower temp.
the column temperature is directly proportional to the abv of the vapor. Stilldragon offers an electric parrot which also compensates for pressure. I like knowing temperature as it quickly gave me an idea of how the column was functioning. When running something like vodka the temperature will be the same during all of the run as you need to maintain a high abv. Thus there is no change that would indicate a cut, except maybe at the end when the temperature jumps.
For a 2,3,4 plate column, If you run the same thing every time with enough experience you may learn where to make cuts based on the temperature. Change a variable and it will be different. I found that I could estimate where to make cuts simply based on volume. Knowing the total volume I knew where the cuts were likely to be simply based on the % of the run. I still checked them by taste.
I think every distiller should know and understand how to use the water-ethanol equilibrium curve. This alone can be used to answer many of your questions...especially for a column still.
Reply:2 hours ago, derek.duf said: