RE: [Distillers] Questions from "Paranoid"
> A} I started the urn thermostat at 80' and it cut out a few times. CouldI
> have set it immediately to 98' [where the thermostat setting ended up ]I'd say to leave it on high. The temperature that the liquid will boil at
> instead of gradually adjusting it up
is dependant only on its alcohol content - it can't boil at a higher
temperature than what the % alcohol will allow (the extra energy goes into
making the vapour, rather than inc the temperature further). So its going
to be doing its own thing anyhow - slowing inc over the coarse of the run.
Best to leave it to it, and instead concentrate your control on getting
the right reflux ratio to deliver the flowrate & purity you desire.
> B} Should I put in some more copper scrubbers to try to increase theincreasing
> purity. I couldn't get the flow rate of distillate any lower by
> the flow of coolant. Column height is 3.5 feet and fixed so can't adjust3.5 foot should be more than capable of better than 80%. Put as much
scrubbers as you can in, without overcompacting them. You're after the
extra surface area. Make sure that its still loose enough though that you
can still easily breath through the column. Pack em too tight, and the
column will "flood" - eg not enough room for the liquid & vapour to pass,
so they both end up at the top - spurting and spluttering and giving really
Talking to a friend today (yeah, I have one), he'd been having problems
with purity, and fixed it by simply insulating the column. This had the
effect of smoothing out the temperatures, and allowed it all to operate
nicely at equilibrium. It stopped surging, and purity picked up heaps, and
it eliminated an "off" taste & smell from the distillate.
Maybe you need to look for a way of being able to increase the reflux ratio
- eg make the coolant more efficient in its transfer of heat. What are you
using - through tubes, a collar, or coils ? Is there some way of increa
sing the cold surface area, or inc the turbulence in the cold water, or
getting better contact between the vapour & the cold surface ?? Any
options there ?
> C} is it likely that any wort regardless of alcohol content will goto
> straight to 78.6' and proceed in the same manner or is it a matter of
> getting used to the idiosyncracies of the individual still and adjusting
> the situationThat top temperature is the result of the purity of the vapour there. For
a tall column, the purity should fairly much be the same for a range of
different starting alcohol contents. Not true for a less effective column
- a higher purity wash will give a markedly inc purity distillate. See the
difference by playing with the wee applett at
http://www.geocities.com/kiwi_distiller/refluxdesign.htm Eg a "two plate"
column with 15% wash will give around 82.1% distillate, but a 5% wash will
give 75.8%, whereas a taller column, say "ten plates", will give 94.5% and