Difference between 3" and 4" bubbler

[virge]

Running a Mac Whisky wash at 85% alcohol to preserve some flavour how much do you collect per hour from a 3" bubbler with 4 plates and how much from a 4"?

[db1979]

4" has close to double the cross sectional area of 3" and should therefore be almost twice as fast. You should be able to get over 2 L per hour from a 4" running fast for flavour retention with flavoured washes (whiskey etc) and I would guess that a 3" might be able to get up to 1.5 L per hour with the same wash and run strategy. I don't own a 3" bubbler and have never run one. Also, I don't often run flavoured washes through my 4" bubbler so when running for vodka or neutral I'll normally get 1.5 L per hour max. From my 2" bubbler I'll get 800 mL per hour max from a flavoured wash.

[navarau]

I have a 4 inch bubbler with 4 plates and a 3 inch bubbler with 9 plates. I get 1.5 litres an hour from the 3 inch and 2.6 litres per hour from the 4 inch.

[virge]

Thanks DB1979 and navaru, I watched a youtube video about a commercial 3" 4 plate glass bubbler and they were running a neutral wash at 92% alcohol at 2.2L per hour and I was wandering if it is true.
Right now I run my MacWhisky washes through a DIY T500 in pot still configuration and I get only 800ml per hour and it is very slow, not even the stripping run can get faster. To run a 27L wash it takes me 7 hours and I waste a lot of time.
Navaru, will your 3" bubbler with only 4 plates have a faster output?
I am a DIY guy and I could easily make a bubbler but here in South Africa the materials are very expensive and if it was to build one it will cost more than 3000 US dollars.
To import a ready made modular with free shipping from China will cost about 350 US dollars for 3" and 650 for 4". If I decide to buy parts from China with free shipping maybe I can save 100 US dollars on each. Knowing what you get from each column size helps me in making a decision.
Thanks again for your reply.

[navarau]

I haven't run the 3 inch with 4 plates as yet but I'm sure it would run faster than running 9 plates. My advice is go the 4 inch if speed is what you are after. I'm going 6 inch soon to reduce run time.

[bluc]

I thought more plates would run faster :think:

[db1979]

I thought more plates would run faster :think:

I don't see why, but even if it did, you've got all those extra plates to load which means more time for the column to equilibrate. Packed sections with plates is a far more economical way of running bubblers for neutral, no packed section and less plates for flavoured.

[bluc]

More plates more seperation more high proof vapour in system. Like a 600mm packed section 2" boka vs 1200mm one. 1200mm one will run faster and maintain abv% vs the 600mm one due to bigger area of working? Area?...

[RC Al]

I thought more plates would run faster :think:

I don't see why, but even if it did, you've got all those extra plates to load which means more time for the column to equilibrate. Packed sections with plates is a far more economical way of running bubblers for neutral, no packed section and less plates for flavoured.

It's faster with more plates because processing vapour through the hot liquid on the plates is more efficient than refluxing it back to the boiler to be heated up again

Good things come to those that wait, i was going to suggest you time the difference by pulling some plates out, but by your sig, yours is not modular, i would think the heat up time difference would be in minutes with 5 extra plates vs 2-5x the reflux ratio to hit the same abv

[bluc]

I wasnt so much thinking heat up time but collection rate. I know wash abv makes a diff. On low abv flavoured wash I get 2-2.5l/h without abv dropping on neutral low wines 40% in boiler i can push to tad under 3.5 without abv drop(only low wines I do is for neutral and I wouldnt do neutral at 3.5l/h as there is flavour carry over). As an example..
With a longer packed section on a 2"boka i can maintain higher xollection rate at same abv compared to a shorter packed section. I figured more plates would do same thing. Hold a bigger buffer to allow faster collection at "x" abv...

[virge]

Thanks for sharing your knowledge guys. Your feedback made me decide to go with 4".
On a 4", 4 bubble plates glass section, can I use a 3" RC? I know, it looks better with 4"RC but on 3" I can add an extra plate below the rounded reducer.