Re: Ambient Temperature Affect
- The lower boiling alcohols is the fore shots and heads rise to the top and get condensed first. that gets returned to the column and mixes with more fore shots and heads rising up the column and so it continues settling into layers in the column. That's the 150ml you chuck away or use as rubbing alcohol. If you draw or collect too fast these layers start to mix up again and this again makes for a weaker ethanol output. A well insulated column goes a long way to keeping these layers in situ (keeping these layers in situ is good for us for better purer production of ethanol) or the technical term for this layered structure is azetrope.
When the boiler and column is at an even temperature from top to bottom, this is the best layered structure of alcohol we as hobby distiller are going to get or azetrope. So insulation is vitally important to achieve the good alcohol separation and collection rate and a shorter time doing the run. (even in a hot climate)
when i get my still to temperature i lower the heat on my burner start to reflux for about an hour.then start to collect product and the temperature stays at 78c for hours.i don't have to adjust the flame again .
--- In Distillers@yahoogroups.com, "edbar44" <edbar44@...> wrote:
> I have a question regarding the outside air temperature and it affect on distillation.
> I did a spirit run several weeks ago and was the best I ever had, took down about 3 gallons of 94-95% ABV in 6 or 7 hours, outside air temp was just around 50F.
> I've got 9 gallons of stripped product so I figured I'd do another spirit run yesterday because it was going to be a nice day.
> Started very early, lit the fire at 7AM, at 8AM it was up to temp, let it reflux for an hour, temp was 78.2C on the column. I start taking off and get maybe 600ML 92%, let it reflux a little longer and pick up 1L of 96% so I'm happy, now something strange happens, air temperature is rising and I'm having some difficulty with the column temp, I take off 200-300ml and the column temp is up to 83C, cooling water is 95F, I lower the fire let it reflux, goes back down to 78.8C, same scenario, 200-300ml and the column is up to 83C again and the product coming off is 89% so I wind up taking down 7 liters of 88-89% product and cannot control the column temperature so what I'm asking is how much does the outside air temperature affect the distillation process, other variables that I should be considering? By afternoon, the air temp was over 80F.
> Thanks for any input.
Thanks for that input but you stated exactly what I have, completely insulated column, heat control, refluxing for an hour or so and this was the first time in a long time that I had any difficulty, of course I will try it again but in checking my records over the past 2 years, I never had a day that had that high of a temp, it really made no sense to me. When the column temp went high, I just let it reflux and it came back down to 78.6 but would go up again within 15 minutes or after getting 300-400ml.