2" Continuous fractionating still

[Bolverk]

Howdy y'all,

So... I've been obsessed with this idea to create a hobby size continuous fractionating still for about a year at this point, and I don't think I'm going to be able to get over the idea until I build it and it's either a success or an utter failure.

After studying various examples of current functioning as well as past patents. I think I may have come up with something that actually might work.

Let me say I mean continuous in that it can continuously be feed wash, NOT let it run continuously unattended. This will be rather low volume, maybe 3 gallons of wash per hour at best. I know lots of people have bigger pots with more power that can out pace this several times over, this is more of an educational endeavor than anything.

The idea is that I'd feed wash in through the heads condenser to preheat my wash, then through a dephlag that would 1. keep hearts cut down in the rectification column and 2. also heat the wash from the peristaltic pump would be all controlled by a PID set at 173°f measured just above the dephlag to be dropped in the analyzer columns at the top. The bottoms temp would be monitored and controlled with a PID to keep it at 212f/100c to ensure I'm not loosing alcohol via bottoms. I imagine the two PIDs will fight each other a bit, but im hoping they will find a balance.

Can I please get your thoughts on this design?

Thanks in advance!

[LWTCS]

Where is the beer feed again?
You will need traps at each product draw.

Edit: ah ok I see it.
My worry is that your feed rate will not provide enough cooling media to ensure a more precise heads take off.

[still_stirrin]

…Can I please get your thoughts on this design?

My thoughts?

A run on either of my stills is a day-long event. That’s more than enough of my time tending to a still for any one day. I can’t imagine what it would take to run a continuous still … I guess maybe “hired employees”. There would be so much maintenance and management activity that I want no part of it.

If you’re goal is a “commercial” product, then maybe a continuous still may be worth it. But, with a 2” column, I can’t imagine it would be anywhere near cost effective. If your goal is “novelty” then maybe you can justify it. But, I sincerely doubt the practicality of such a small scale setup. Batch processes on such a small still just make more sense.

My thoughts, because you asked.
ss

[LWTCS]

Though in my heart of hearts I hope you finish the experiment to prove me wrong.

By the way for the segment of the community that pays attention to the continuous still subject matter, I now have practical confirmation that 380 watts per gallon is doable.

I personally would still recommend the original 408 watts per gallon as a good bench mark.
As I recall Steve A settled on 418 watts after initially being skeptical.
So more good practical data.

[LWTCS]

…Can I please get your thoughts on this design?

My thoughts?

A run on either of my stills is a day-long event. That’s more than enough of my time tending to a still for any one day. I can’t imagine what it would take to run a continuous still … I guess maybe “hired employees”. There would be so much maintenance and management activity that I want no part of it.

If you’re goal is a “commercial” product, then maybe a continuous still may be worth it. But, with a 2” column, I can’t imagine it would be anywhere near cost effective. If your goal is “novelty” then maybe you can justify it. But, I sincerely doubt the practicality of such a small scale setup. Batch processes on such a small still just make more sense.

My thoughts, because you asked.
ss

Hmm, well if he can engineer optimal cooling, I'd say he can be dripping product in less than 10 minutes. That alone seems like a worthy goal.

[Bolverk]

Larry,

at 418 with my 1650w element that would be 3.94 gph. I fear if I plumb the beer into the dephlag first it will be too cold to allow the head to pass hence the heads condenser first. Maybe instead of using an 18" PC for the first HX I installed a 8" dephlag above it and use water in the heads condenser?

[tommysb]

Bolverk -

I say go for it. As to a comment on the design - I don't know. You, yourself say that you want to do this 'just because', for an educational endeavor.

I made a minimum viable setup of a continuous stripping still last summer, using pieces that I had around. No PID control, all manual.

Did it work? Not perfectly. But yes, if i ran it slower than I wanted.

Did I have fun? Yes.

Did I learn something? Yes. A lot.

Building it will be the best way to work out which pieces work/don't work. (e.g. your fighting PIDs). Seeing it in action will probably help to engineer a solution/fix to any imperfect parts.

[LWTCS]

Recovering heat from your effluent stream will provide the most heat transfer with respect to preheating your beer.

[Bolverk]

Recovering heat from your effluent stream will provide the most heat transfer with respect to preheating your beer.

Agreed, every successful continuous still I've seen utilized their effluent stream as a preheater for the beer. I'll reconfigure to include that... just thought I might be able to exclude that part because the dephlag above the rectifying plates will also act as a preheater.

I think the challenge I'm running into/going to run into is not if I can get the beer hot enough, it's if I can keep the heads gate stable enough to let the heads pass and keep the hearts down without the need for a chiller. The best source of stable temp water for the dephlag I have is going to be the wash. I can but I don't feel right about running tap water for hours and hours just for this, I live in AZ, my water usage needs to be more responsible than that.

Another idea is that I can split the beer feed stream, similar to how cotherman did on his column (0:50 of this video but for me the feed will got to the heads gate (regulated by a valve) the other to the heads condenser, then recombine at the beer inlet?

[Bolverk]

Revised drawing with split beer stream using bottoms HX

[drmiller100]

6 foot tall column. Use condenser to warm beer.
Use directional heat exchange to further heat wash from runoff from boiler..
Insert heated wash half way up the column
The bottom half of the column needs to be about the double the squared of the top half. So if the top is 3 inch bottom can be 4 inch (3*3)=9. (4*4)=16

I did do 2 and 3. 2*2=4. 3*3=9. For top and bottom. I could only get marbles to work on a 72 inch tall column. No other packing g worked for me.

I only did fuel at 95 percent and you can't strip heads off. More info in the fuel forum this site.

[Bolverk]

I still haven't moved forward on this design because I'm not sure on a few factors yet.

Here is the latest design I'm ruminating on.

The beer side will be 2" x 4ft tall with 8 spool filter plates with 6mm holes to create the cavitation needed to strip the incoming beer. My goal in the beer/stripping side is 40% from a 7-8% wash.

The spirit side will have a small boiler that sits in the bottoms and I guess will work kind of like a bane marie/parasitic boiler to heat the low wines. What I'm unsure about is the the LM side and how big it should be, I'm leaning towards 3" or 4". Any thoughts on this? Is their an ideal vapor speed range I should be shooting for with LM?

[drmiller100]

Go find the graph and look up what vapor comes off an 8 percent wash. I bet it is about 40 percent which means you don't need the one column.

How much alcohol are you willing to waste on the beer side? The more plates the less wastage. Energy doesn't change.

As for diameter how much energy are you running?

[Bolverk]

Go find the graph and look up what vapor comes off an 8 percent wash. I bet it is about 40 percent which means you don't need the one column.

How much alcohol are you willing to waste on the beer side? The more plates the less wastage. Energy doesn't change.

As for diameter how much energy are you running?

8% comes off the beer side at about 45%, then into the parasitic boiler and would redistill to about 75-80% then through the plates.

Ideally as little as possible, but if I can get <1% I'd consider this a success. I was thinking that after initial experiments I could add packaging as needed to minimize the losses.

Planning on a 3500w element. Based on the previous numbers I've seen (408w per gallon per hour) that's should be enough to process about 8.5gph, but that didn't include a parasitic boiler so I'm guessing it wont be that high for me.

[drmiller100]

Go find the graph and look up what vapor comes off an 8 percent wash. I bet it is about 40 percent which means you don't need the one column.

How much alcohol are you willing to waste on the beer side? The more plates the less wastage. Energy doesn't change.

As for diameter how much energy are you running?

8% comes off the beer side at about 45%, then into the parasitic boiler and would redistill to about 75-80% then through the plates.

Ideally as little as possible, but if I can get <1% I'd consider this a success. I was thinking that after initial experiments I could add packaging as needed to minimize the losses.

Planning on a 3500w element. Based on the previous numbers I've seen (408w per gallon per hour) that's should be enough to process about 8.5gph, but that didn't include a parasitic boiler so I'm guessing it wont be that high for me.

Just like it takes a lot of plates to get all the way to 95, it takes a lot of plates to get under 1 percent at the bottom. It is the same chart. The middle has big changes for each boil but the ends of the chart require lots of boils to get that last bit.

I ran 20 to 25 gph of 10 percent beer on a 4000 watt element and pulled azeo. The batch numbers are different than continuous.

I do question 3500 watts on a 2 inch column especially for the beer stripper but I'll defer to someone who has more experience with plates.

I used marbles and settled on 4 inch for the beer stripper.

[Bolverk]

Just like it takes a lot of plates to get all the way to 95, it takes a lot of plates to get under 1 percent at the bottom. It is the same chart. The middle has big changes for each boil but the ends of the chart require lots of boils to get that last bit.

I ran 20 to 25 gph of 10 percent beer on a 4000 watt element and pulled azeo. The batch numbers are different than continuous.

I'm not planning anywhere near 95%, 65-70% would be ideal. Im counting on a certain amount of inefficiency in the spirit column.
(This is the part I'm struggling with)

I just want to avoid as much loss in the beer column as reasonably possible. So the plates/packing its going to require some experimentation to get right in a 4.5ft column.

[drmiller100]

Put a doubler or thumper on top of the beer column and you are at 65 to 70.
Use the rest of your height for the stripper and boiler

[drmiller100]

Put a doubler or thumper on top of the beer column and you are at 65 to 70.
Use the rest of your height for the stripper and boiler

Also all else bei g equal the stripper needs about twice the cross section area as the spirit side.
So beer 4 inch spirit 3 inch.

[Bolverk]

Put a doubler or thumper on top of the beer column and you are at 65 to 70.
Use the rest of your height for the stripper and boiler

Thanks but that won't let me make cuts...

The spirit side will have draw plates at different levels that will hopefully (if I can figure it out) be a desirable hearts cut.

[Bolverk]

Also all else bei g equal the stripper needs about twice the cross section area as the spirit side.
So beer 4 inch spirit 3 inch.

I could do that, but 4" beer side seems like overkill. a 12' 4" column can strip something like 35gph... im only shooting for like 5ish gph.

[drmiller100]

Put a doubler or thumper on top of the beer column and you are at 65 to 70.
Use the rest of your height for the stripper and boiler

Thanks but that won't let me make cuts...

The spirit side will have draw plates at different levels that will hopefully (if I can figure it out) be a desirable hearts cut.

Pulling at different levels for different cuts absolutely will not work on continuous or batch.

Have you ever ran any kind of still?

For a 2 inch column 1000 watts will be closer.

[Bolverk]

Pulling at different levels for different cuts absolutely will not work on continuous or batch.

Pulling at different levels from a continuous beer stream is the basis of the coffey design and is very common on commercial stills (which is what I'm trying to replicate on a much smaller scale).

Have you ever ran any kind of still?

I could ask you the same. I'm trying to make booze not fuel, which so far your recommendations will only work for. Thanks for commenting but I don't think making drinkable alcohol is your thing.

For a 2 inch column 1000 watts will be closer.

Clearly

[OtisT]

Oops. Misread that.

[drmiller100]

Pulling at different levels for different cuts absolutely will not work on continuous or batch.

Pulling at different levels from a continuous beer stream is the basis of the coffey design and is very common on commercial stills (which is what I'm trying to replicate on a much smaller scale).

Have you ever ran any kind of still?

I could ask you the same. I'm trying to make booze not fuel, which so far your recommendations will only work for. Thanks for commenting but I don't think making drinkable alcohol is your thing.

For a 2 inch column 1000 watts will be closer.

Clearly

Those solutions tend to be a little taller than 4 feet.

Good luck and I hope you prove me wrong!!!!

[Bolverk]

Those solutions tend to be a little taller than 4 feet.
Good luck and I hope you prove me wrong!!!!

Agreed
Thanks

[Bolverk]

By the way for the segment of the community that pays attention to the continuous still subject matter, I now have practical confirmation that 380 watts per gallon is doable.

Howdy,

Rereading this thread and i relized I missed this...
What were the conditions that made 380w per gallon doable?

[drmiller100]

By the way for the segment of the community that pays attention to the continuous still subject matter, I now have practical confirmation that 380 watts per gallon is doable.

Howdy,

Rereading this thread and i relized I missed this...
What were the conditions that made 380w per gallon doable?

It works with continuous fractionating still.

Fwiw I was more like 200 watts per gallon of beer. You have to pull 95 to do that though.