SPP Vs Scrubbers on a short column
Hi. Yesterday and today I had a bit of time on my hands.
I had some high proof from an all heads run back in April that I wasn't happy with.
I had added lots and lots of calcium carbonate to my heads to try and help neutralize some of the esters and make the product more neutral. What I ended up with was 9L of 95.6% hearts that had a slight taste of calcium carbonate
At least I have plenty of junkahol for any new builds - or it might clean up with filtering.
So I decided to charge the small still with some of this and run the stumpy VM with SPP then with stainless scrubbers on the same power settings, to see what the difference in performance would be.
I have been running this stumpy VM with a bubble plate on the keg boiler for white rum, with SPP I was unable to shift it off of azeotrope, so had switched back to scrubbers.
Before yesterday I had not ran it without the bubble plate.
here is the still (it's way off plumb in this pic, It was sorted before the boiler was warmed up)

Saturdays run -
15L in the boiler @ 30%
Column packed with 3" of copper mesh and 9" of SPP
Power approx 1500W (I have trouble measuring the actual power due to the type of controller I'm using, but it was the same setting for both runs)
Sundays run -
15L in the boiler @ 30%
Column packed with 3" of copper mesh and 9" of scubbers - really densely packed.
The comparison. (I took product off at different take off speeds for comparison) SPP were measured at 21oC and it was cooler today so the scrubbers were measured at 19.5oC
All the measurements were taken with a narrow rage 90-100% alcometer, so are pretty accurate.
With SPP I was able to achieve 95.7% (@21oc) running 800ml/h
Below are the other results matched up with the closest take off rates.
SPP 95.5% @ 930ml/h SS - 93.7% @ 900ml/h
SPP 95.3% @ 1100ml/h SS - 92.7% @ 1110ml/h , 92.5% @ 1140ml/h
SPP 95.1% @ 1350ml/h SS - 92.7% @ 1410ml/h
So it looks like azeotrope is achievable somewhere between 800 and 930ml with the SPP, I couldn't get anywhere near it with the scrubbers.
And at other take off rates the SPP looks to be good for about an additional 2% ABV with this very short column.
I had some high proof from an all heads run back in April that I wasn't happy with.
I had added lots and lots of calcium carbonate to my heads to try and help neutralize some of the esters and make the product more neutral. What I ended up with was 9L of 95.6% hearts that had a slight taste of calcium carbonate
At least I have plenty of junkahol for any new builds - or it might clean up with filtering.
So I decided to charge the small still with some of this and run the stumpy VM with SPP then with stainless scrubbers on the same power settings, to see what the difference in performance would be.
I have been running this stumpy VM with a bubble plate on the keg boiler for white rum, with SPP I was unable to shift it off of azeotrope, so had switched back to scrubbers.
Before yesterday I had not ran it without the bubble plate.
here is the still (it's way off plumb in this pic, It was sorted before the boiler was warmed up)

Saturdays run -
15L in the boiler @ 30%
Column packed with 3" of copper mesh and 9" of SPP
Power approx 1500W (I have trouble measuring the actual power due to the type of controller I'm using, but it was the same setting for both runs)
Sundays run -
15L in the boiler @ 30%
Column packed with 3" of copper mesh and 9" of scubbers - really densely packed.
The comparison. (I took product off at different take off speeds for comparison) SPP were measured at 21oC and it was cooler today so the scrubbers were measured at 19.5oC
All the measurements were taken with a narrow rage 90-100% alcometer, so are pretty accurate.
With SPP I was able to achieve 95.7% (@21oc) running 800ml/h
Below are the other results matched up with the closest take off rates.
SPP 95.5% @ 930ml/h SS - 93.7% @ 900ml/h
SPP 95.3% @ 1100ml/h SS - 92.7% @ 1110ml/h , 92.5% @ 1140ml/h
SPP 95.1% @ 1350ml/h SS - 92.7% @ 1410ml/h
So it looks like azeotrope is achievable somewhere between 800 and 930ml with the SPP, I couldn't get anywhere near it with the scrubbers.
And at other take off rates the SPP looks to be good for about an additional 2% ABV with this very short column.