Glass Marbles for Reflux Column Structured Packing

[DAD300]

There is another factor here between marbles vs scrubbers/wire mesh.

It's easy to say it takes XX number of 1/2" glass marbles to fill a 2" diameter by 30" tall column. But stuffing scrubbers or wire mesh into a column is subjective. You can fill the same space with one, or three pounds of wire mesh and the results are dramatically different.

I think the home calculator was based on an optimized scrubber/mesh filled to volume vs void ratio. Few people actually test for the right amount of packing.

engunear, you can use the calculators to backwards calculate your number of plates or HETP. If you know your power, boiler charge, dia , height of column and abv achieved at each stage of collection, you can make an assumption as to the number of plates. Then pack the column with more or less void and run again.

Wire mesh packing is more subjective than marbles.

[engunear]

engunear, you can use the calculators to backwards calculate your number of plates or HETP.

[

Thats what I've done, except instead of laboriously clicking numbers, I've copied the equations into Python, written binary search algorithms so I can go backwards as well as forwards and plotted them out. Code was checked by regenerating the standard graph for boiling points of liquid and vapour.

quote]Also, the numbers used for glass marbles are off based on calculations I did after seeing how well they performed compared to scrubber material...[/quote]

Does anyone have data they can share?

A column with 18.7 ETP should have binary output - azeotrope or water. If the calculator is off by 2X it should still have binary output. That is not my experience. I have no data yet, but I'll be surprised if I have 3 equivalent plates, eyeballing the graph. Its several weeks till I can get data, till then its asking questions and a bit of hacking and thinking. But my gut is saying something in my build is way off.

It takes a lot of work to squeeze out each additional HETP beyond that point

For increasing HETP, what you say sounds sensible. I think I used HETP when I meant ETP. But adding length should always increase ETP, yes (?).

[Hound Dog]

I just took the packing out of the column and filled it with marbles to find it ran better. The math is cool and all but it depends on how your still runs.... Switching back to lava rock for a couple of runs to judge against them again.

[Hound Dog]

Hmmm. My wife is drinking the recent run where I switched back to rocks. I have to say the vote is in for rocks right now. Might try some more runs in a few months after I run some rum and whiskey.

[rad14701]

Yep... A lot depends on the still itself as far as what structured packing works best...

[engunear]

Here is another graph that shows how you can measure how many equivalent plates your still has. You probably want to wash new packing before you use it, so this can be done at the same time. I believe in the vibe and the meter.

So what you do, is mix up a batch of water and alcohol, to a known ratio. Lets say 100 ml alcohol in 10 litres (1%). Put your still on full reflux, and let it sit. It will wash the crap out of your packing. But when its stable, measure the head temperature. This is the blue line on the plot if its 1%.

If you have one equivalent plate (i.e. a pot still) you will be at 99C, two plates 94C, three plates 83C, four plates 79C, and beyond that, its almost impossible to measure. If you start off more dilute you will barely fill the column. Maybe it will work as a measurement.

This corresponds with the comment that it is hard to get better than 3-4 plates. Beyond that, you can't measure it even if you have 20 plates.

My column still, gut feel, is doing about 2.5 plates in 2 meters. Crap. Can measure right now because we are on different continents. But in time.

By the way, if anyone does attempt this, pls share results. Maybe the method is bogus, maybe the equations don't work at the edges. Its all interesting whatever.

[Hound Dog]

You just try and make things complicated. I will just run some liquor and see how it tastes.

[engunear]

I didn't make the complication, I just found it under my feet and tried to understand it.

Someone told me once that if you take a subject, even a well known subject, and science the shit out of it, you always find a piece of gold. That graph has prompted me to at least measure my column (a 1 hour job), and probably rebuild it. I've thought for 15 years that my 2m column with packing was so good that it would be hard for anyone to improve upon. Now I'm thinking it needs some serious rebuilding. How my liquor will taste after I've rebuilt it, and having a quite drink thinking "yep, that makes sense" will be my pieces of gold.

[Hound Dog]

This is the good thing about this forum and hobby. We all enjoy different aspects of it. I am glad we have guys on here that can "science the shit" out of things so we can get reality checks from all sides.

[engunear]

Hear hear ! (thats Shakespearean for +1) !!!!!!!!!!!!

[raketemensch]

Hmmm. My wife is drinking the recent run where I switched back to rocks. I have to say the vote is in for rocks right now. Might try some more runs in a few months after I run some rum and whiskey.

Maybe some tails sticking around helps with flavor. Wouldn't be surprising to me.

[Bagasso]

Hmmm. My wife is drinking the recent run where I switched back to rocks. I have to say the vote is in for rocks right now. Might try some more runs in a few months after I run some rum and whiskey.

Both glass marbles and lava rock are mostly made up of the same thing, silica.

Silica gel is used as packing in gas chromotagraphy.

Just 2 bits worth.

[thecroweater]

Hmmm. My wife is drinking the recent run where I switched back to rocks. I have to say the vote is in for rocks right now. Might try some more runs in a few months after I run some rum and whiskey.

Maybe some tails sticking around helps with flavor. Wouldn't be surprising to me.

Tails help make a neutral taste better no they do not, great I'm glad my neutral is smeared the blazes was said by no one ever

[raketemensch]

Tails help make a neutral taste better no they do not, great I'm glad my neutral is smeared the blazes was said by no one ever

No one said anything about smearing. What makes lava reflux taste better than marble?

I'm not saying that I'm right by a long shot, just wondering what makes the difference. It's probably just a personal preference. I've had several people call my white UJ "vodka," and I've had some store-bought white shine that was down to a tiny hint of something floral.

The most neutral of neutrals has some flavor to it. Is it the yeast? The grain? Some leftovers on the packing? All of the above?

[engunear]

Maybe some tails sticking around helps with flavor. Wouldn't be surprising to me.

I'm a bit confused over what people are wanting from their reflux stills and their packing. The "test of goodness".

When making vodka for gin I want a totally clean spirit i.e. lots of plates.

True grappa is made from left over solids from wine making (marc) and has more intensity than distilled wine. I find it easier to do the concentration part with a still having stripped skins and wine together, than try to physically separate them to treat separately. So on second distillation, I start with high reflux, pull out the nail polish, back off reflux, pull out some vodka, run to the end, and back blend the flavour with the vodka till I get the intensity right. The more you blend, the more you have, but if you go too far its boring, so there is a second variable there.

So for me, more plates equals more flexibility and faster runs equals better.

The crossover from science to art is where we go from "this still has X equivalent plates, because it was measured using method Y and we all agree that is valid" is science, and "I ran my reflux still set for Z equivalent plates, with a ferment of blah blah and it tastes like yada yada" is art. And "I drank some watching the sunset" is life.

So what are your tests of goodness, and are we talking science, art or life?

[masonsjax]

I consider all three when making decisions, but the life part will always trump the others.

[Hound Dog]

Engunear, I run a LM and believe clean odorless, tasteless is a neutral. My wife likes this best and it is great for mascerations. For flavored drinks I have done it by blending but have had better results letting the still do the smearing. Take fores and heads as you say, then just run faster to allow a bit of tails smear come through. I can see by blending you would have more control over this but I have not mastered it.

[bluefish_dist]

A little feedback on marbles in my rig. The rig is a lm/vm with 3 plates under a 60" column. The 60" is two spools, one 36", the other 24". All 4" on a 15 gal keg with a 5500 watt element. I went to marbles based on the positive results others had posted. Since they are somewhat expensive for lab grade, I started with enough to fill about 2 ft of the column, then scrubbers for the balance of 3 ft. The other 24" was spp from big swede. Output at 14 amps was 3.8 min per 100ml while holding 163.9 deg. At 6100 ft that's 190 proof. Not the performance I expected.
I swapped out the marbles and ran with 36" of scrubbers. Output rose to 2.8 min per 100ml. Still able to hold 163.9. Still not what I was expecting.
Swapped out the spp for scrubbers and tried again. Output improved to 1.15min per 100ml and the temp dropped to 163.5. I could also run 15 amps without flooding. Proof is 190.8.
So I am not sold on marbles or the spp from big swede. Simple scrubbers run better and are a lot lighter. Also a lot cheaper. It was still almost $100 worth of scrubbers.

[rad14701]

A little feedback on marbles in my rig. The rig is a lm/vm with 3 plates under a 60" column. The 60" is two spools, one 36", the other 24". All 4" on a 15 gal keg with a 5500 watt element. I went to marbles based on the positive results others had posted. Since they are somewhat expensive for lab grade, I started with enough to fill about 2 ft of the column, then scrubbers for the balance of 3 ft. The other 24" was spp from big swede. Output at 14 amps was 3.8 min per 100ml while holding 163.9 deg. At 6100 ft that's 190 proof. Not the performance I expected.
I swapped out the marbles and ran with 36" of scrubbers. Output rose to 2.8 min per 100ml. Still able to hold 163.9. Still not what I was expecting.
Swapped out the spp for scrubbers and tried again. Output improved to 1.15min per 100ml and the temp dropped to 163.5. I could also run 15 amps without flooding. Proof is 190.8.
So I am not sold on marbles or the spp from big swede. Simple scrubbers run better and are a lot lighter. Also a lot cheaper. It was still almost $100 worth of scrubbers.

What diameter marbles are you using...???

What %ABV do you get with just the three plates and no extensions...???

I wouldn't discount marbles or SPP until you have run the entire 60" with a single type of structured packing, but I could understand not wanting to incur any additional expense to do so... That will be a lot of weight in glass, however... SPP would be lighter, but not as light as scrubbers... Mixed packing media is not as efficient as single media...

I am at ~1300 feet above sea level...

[bluefish_dist]

10mm or 3/8" marbles. The difference between marbles and scrubbies was not all that much, so it may be worth trying again. Lab grade makes it a $500 bill to get enough marbles.
I have not run the 3 plates over low wines, but they will pull 180 proof from 10% and flood at 25 amps on the big still.
I tried the spp on my 2" column and it didn't work as well as scrubbies. I didn't have hard data like this. Could simply be this design of spp isn't all that good. I did run 50" of 2" above the 3 4"plates with spp and could get 1/2 gallon an hour but it struggled to get to 190 proof corrected.
Since I have to hit 190+ that little bit matters. It would not be an issue with a home distiller.

[Hound Dog]

A little feedback on marbles in my rig. The rig is a lm/vm with 3 plates under a 60" column. The 60" is two spools, one 36", the other 24". All 4" on a 15 gal keg with a 5500 watt element. I went to marbles based on the positive results others had posted. Since they are somewhat expensive for lab grade, I started with enough to fill about 2 ft of the column, then scrubbers for the balance of 3 ft. The other 24" was spp from big swede. Output at 14 amps was 3.8 min per 100ml while holding 163.9 deg. At 6100 ft that's 190 proof. Not the performance I expected.
I swapped out the marbles and ran with 36" of scrubbers. Output rose to 2.8 min per 100ml. Still able to hold 163.9. Still not what I was expecting.
Swapped out the spp for scrubbers and tried again. Output improved to 1.15min per 100ml and the temp dropped to 163.5. I could also run 15 amps without flooding. Proof is 190.8.
So I am not sold on marbles or the spp from big swede. Simple scrubbers run better and are a lot lighter. Also a lot cheaper. It was still almost $100 worth of scrubbers.

If you are getting 180 from the plates, how are you not easily attaining azeo with 60 inches of column on top. At 4 inches is one burner enough to keep it fed? I run more power than that into a 3 inch column with a 6 inch single plate bubbler under it. I went back to lava rocks. For the last run and may try it again for another couple before trying marbles again. May just be a comfort zone thing but I do pretty good with rock. Playing it a plated column in between things now too.

[bluefish_dist]

Are you using high precision Hydrometers? I am using a 185 to 205 and adjusting for temp. Unadjusted its reading about 195 at 80 deg. I could get 190 with all the setups, but had to run a lot of reflux. The limiting factor for power is the plates. I can run 15 amps @ 205-209v, but if I go to 16a the plates flood. I am going to go to 6" plates shortly which should allow more power.
I may go back and try marbles again as the difference was not that much when I changed them to scrubbies. The bottleneck seemes to have been the SPP. I was just not able to make the SPP work. I tried it in the 2" with and without plates underneath and with various heat inputs. It didn't match temp or output of the scrubbies.

[still_stirrin]

Bluefish,

Since you're willing to "throw money at it", have you tried ceramic rashig rings? Don't want to leave that stone unturned in search of the elusive 1/4%...
ss

[Hound Dog]

No I use a regular hydrometer because I don't have to report to a regulator. But both that I have read the same so I am reasonably sure I am where I need to be. I run low wines not just a wash but it just seems easy to get over 190 with a packed column. I know in reading posts from Odin, he discouraged using plated sections under a column with SPP. He claimed that the higher proof of alcohol would just flood and not separate right with SPP. I have not found that to be the case with marbles or rocks.

[bluefish_dist]

I tried the spp alone and many heat inputs. I couldn't make it work. I found that I got the best output over plates. With my 2" column over 3 4" plates and 50" packed I could pull a little less than 1/2 gallon per hour.

From the recent testing I think marbles are better than the parent site calculator suggests, but not quite as good as scrubbies. I would like to try a full column of marbles, but I don't trust buying them at hobby lobby. Lab grade are expensive so that will be in the future some time.
I am finishing up 2 days of still runs and with my rig I have been pulling slightly more than a gallon per hour at 190+. That is what I would expect for a 4" and seems to match the parent site calculator as closely as I can tell.

[Bobbywolf]

I picked up some clear glass mini marbles, 7/16 in size, and it sure does take alot of them to fill my 3" column. 1kg (2.2lbs) will fill only 6.5" of 3" column. I need roughly 7kg (15.4lbs) to fill my column. They cost 10.99 per kg

Anyway I have 4kg, but didn't want to muddy my results by mixing packing for my latest run so I'm holding off till next run when I can get another 3kg, and run with no copper scrubbies (except for one in my condensers center).

These marbles when stacked in a column seem really densly packed. I've never had flooding issues, but is it something small marbles are prone to doing?

[Hound Dog]

I run a 3" also. I would think that marbles that small will have flooding issues but it depends on how hard you are used to running. I found 5/8" worked well for me. Try it and see. Please post your results for us all to learn.

[rad14701]

These marbles when stacked in a column seem really densly packed. I've never had flooding issues, but is it something small marbles are prone to doing?

I am doubtful that you will encounter flooding with marbles due to the amount of voidage within the column... I'd love to have some marbles that size but haven't found any locally and the weight issue makes ordering them somewhat cost-prohibitive, at least for someone as frugal as me...

[Bobbywolf]

Well, my first mini marble run is complete and I gotta say I like it! Initially, It flooded as soon as it came up to temperature. I could hear the marbles rattling around for a min then it started pissing out my temp sensor hole as the liquid overwhelmed my bokas head.

Once I dialed the input heat back, and got things to stabilize, I was able to run it at a quicker takeoff, AND at a lower power level than with copper scrubbies. This tells me there is much more reflux going on and is more efficient. I also now know that rattling marbles means too much power lol.

Once I get it dialed in after a couple more runs, I see this as being the way to go.

Im a convert.

[Tomb]

Bobbywolf:

What is your source for the minimarbles?
(I am Western Canada)

T