Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

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MereCashmere
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Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by MereCashmere »

After a good talk with Saltmustflow and after hours of reading, it seems as though this board is again fairly split on the “semi- flooded” state of packed columns. From my reading from about 2015-2018 most of you here were all in on it; then after that it seems that some of you came to the conclusion that it just isn’t worth the effort and running a bit slower with a non- flooded column made the day much more enjoyable. So where do we stand now? I’m tempted to experiment with a non flooded column for the sake of experimentation. So some questions for y’all;

1; Do you find yourself increasing the boiler power during the run to keep the fluid bed constant and your output high or do you increase your reflux and keep your power the same but takeoff slower during the run?

2; Do you find you get the same results If you run a semi- flooded state vs a non flooded column? How do you currently run?

I think it would also help if we posted our columns size and packing material to inform others. It’s hard to research such topics for hours only to find out most are using a column half or double the size of your own.

I’ve got a 3”x36” lava rock packed CCVM; semi- flooded at 3500watts and by the end of the run I’m just over 4000 watts if I want to keep takeoff the same.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Salt Must Flow »

I run very very slow 2200W (3 drops per second) at first then after a while I'll take-off just a bit faster. Once I know I'm into hearts, I'll turn the power up 2750W, stabilize and go for fastest take-off (3 lph or a bit higher). I imagine I could take-off faster, but I really hate heads so I assume going slower compresses heads better up front.

I never tried to flood deliberately. Whenever I've noticed that my ABV was dropping, I heard my column fizzing, making a sizzling sound. I believe that was the sound of flooding. I was using teased out stainless scrubbers at the time and they' are finicky to being packed too tight or too loose. Ceramic packing floods easily, didn't work well and when it flooded I also noticed a drop in ABV. These experiences do not necessarily mean anything regarding the aim of this topic. Maybe I just packed the scrubbers too tight and that's what happens with scrubbers. Ceramic sucks so it probably just sucks worse when flooded.

I have never tried to flood my lava rock packing, but if my spirit hydrometer doesn't say 97% ABV at 60F then I won't be satisfied. I've always been leery of running with too much power, have been content with a bit over 3 lph, but wouldn't mind taking off faster without compromising quality. I don't mind stepping up power bit by bit and testing higher take-off rates though. I think I'll try testing more with my next run.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by zapata »

There is support in academic and industrial literature to support thoroughly wetting the packing may actually be where this "semi-fluidized bed" talk actually came from. At least it's as close as I can trace it before I get lost translating outside of english. A number of authors suggested overloading and flooding the column to wet it out, but I don't see where this was intended to be maintained, just done once to saturate the packing. Other authors accomplish the same in different ways, like filling the boiler through the column. Maintaining a level of liquid above the packing throughout a run seems to be a hobbyist practice.

Not to say anything against it. Just that initial flooding and maintaining the flood are distinct things, possibly with distinct functions.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by MereCashmere »

zapata wrote: Tue May 17, 2022 1:47 pm There is support in academic and industrial literature to support thoroughly wetting the packing may actually be where this "semi-fluidized bed" talk actually came from. At least it's as close as I can trace it before I get lost translating outside of english. A number of authors suggested overloading and flooding the column to wet it out, but I don't see where this was intended to be maintained, just done once to saturate the packing. Other authors accomplish the same in different ways, like filling the boiler through the column. Maintaining a level of liquid above the packing throughout a run seems to be a hobbyist practice.

Not to say anything against it. Just that initial flooding and maintaining the flood are distinct things, possibly with distinct functions.
I would think with the rising vapors the column will wet regardless; that said I typically do one and done runs and maintain azeo or above so I rarely if ever use low wines; perhaps that would make a difference.

Where do you stand on the subject Zapata?
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by MereCashmere »

Salt Must Flow wrote: Tue May 17, 2022 12:21 pm I run very very slow 2200W (3 drops per second) at first then after a while I'll take-off just a bit faster. Once I know I'm into hearts, I'll turn the power up 2750W, stabilize and go for fastest take-off (3 lph or a bit higher). I imagine I could take-off faster, but I really hate heads so I assume going slower compresses heads better up front.

I never tried to flood deliberately. Whenever I've noticed that my ABV was dropping, I heard my column fizzing, making a sizzling sound. I believe that was the sound of flooding. I was using teased out stainless scrubbers at the time and they' are finicky to being packed too tight or too loose. Ceramic packing floods easily, didn't work well and when it flooded I also noticed a drop in ABV. These experiences do not necessarily mean anything regarding the aim of this topic. Maybe I just packed the scrubbers too tight and that's what happens with scrubbers. Ceramic sucks so it probably just sucks worse when flooded.

I have never tried to flood my lava rock packing, but if my spirit hydrometer doesn't say 97% ABV at 60F then I won't be satisfied. I've always been leery of running with too much power, have been content with a bit over 3 lph, but wouldn't mind taking off faster without compromising quality. I don't mind stepping up power bit by bit and testing higher take-off rates though. I think I'll try testing more with my next run.
I mean if there’s no need for it, I don’t see a reason for it since it tends to take way more attention than just setting a power and letting it run. I’m okay with slightly slower runs if it means a more relaxed run.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by StillerBoy »

I been an advocate of running a reflux still in semi flooded state for many yrs now, main reason is for the ease of operation providing for a consistent result and time saving.. operating in a semi flooded state is best done using a slight glass, as without one, it’s really a hit and miss for a consistent refluxing column equilibrium.. running in a semi flooded state with packing is really no different than a flooded plate in a flute..

I operate a concentric LM with a 2 x 35" column, packed with 3/16 - 1/4" lava rocks that have been compressed while loading, with a slight glass at top of packing.. the boiler is power by a 5500w element on a controller managing the amperage to maintain a flooded level between 1/4 - ½" above the packing throughout the run..

the column is operated during the run in this manner.. from start to 150*F at base of column, (have temp probe at base of column and 3" above the packing), at which time the power is reduced from full to 12 amps, and maintain until the vapor breakthrough the packing, once vapors have broken through the power is raised to 13.5 amps and maintain until the column starts to show signs of flooding, at which time power is reduced by about 1 amp and adjusted to maintain the flooding level desired..

one flooding has established, fores and heads are extracted at rate of 100ml per 10 - 11 min until out the head section (800ml).. at that point I switch to extracting the body section at 3 different extracting rates, as the front section is always the cleanest.. first section is extracted at rate of 550ml per 12 min for the next 4 jars, then at that point in the run I start the compress the extraction rate some, at rate of 525ml per 12 min for the next for 4 jars, at which point I compress the extraction rate again, down to 425ml per 12 min for the next for 4 jars, at which point I now extract the tail section again compressing them..

Over the yrs of doing the same sugar wash ABV, I’ve come to know where the cut points are, and the about run explanation is for a 7 gal run at 40% ABV.. and I'm of the view that the still is there the job I want it do for me, not the other way around, and I'm not an advocate of babysitting a still any more than I have too..

So to answer the questions above, 1) I’ve never notice any different in the finish product quality between the semi flooded and non semi flooded.. what I’ve experienced ease and a time saving of almost 1 hr per run ( from just over 6 hrs to just over 5 hrs).. 2) in the power management there is some adjustment required.. as stated above, I start full power, reduced power at the 150* mark until the vapor breakthrough, them increase power until semi flooded occurs, then I reduce power some to the level required to maintain the required level of flooding during the head extract phase.. In the early section of the body extraction, my power is increase to, again, maintain the semi flooded state in relation to the extraction rates mention.. I maintain the semi flooding required by adjusting the power, so yes there is power adjustment throughout the run, and also in maintaining the same ABV results..

Mars
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by zapata »

Specifying amperage alone doesn't translate, your voltage is 240v? So your power is from 2880 watts to 3240 watts?
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by MereCashmere »

StillerBoy wrote: Tue May 17, 2022 2:57 pm I been an advocate of running a reflux still in semi flooded state for many yrs now, main reason is for the ease of operation providing for a consistent result and time saving.. operating in a semi flooded state is best done using a slight glass, as without one, it’s really a hit and miss for a consistent refluxing column equilibrium.. running in a semi flooded state with packing is really no different than a flooded plate in a flute..

I operate a concentric LM with a 2 x 35" column, packed with 3/16 - 1/4" lava rocks that have been compressed while loading, with a slight glass at top of packing.. the boiler is power by a 5500w element on a controller managing the amperage to maintain a flooded level between 1/4 - ½" above the packing throughout the run..

the column is operated during the run in this manner.. from start to 150*F at base of column, (have temp probe at base of column and 3" above the packing), at which time the power is reduced from full to 12 amps, and maintain until the vapor breakthrough the packing, once vapors have broken through the power is raised to 13.5 amps and maintain until the column starts to show signs of flooding, at which time power is reduced by about 1 amp and adjusted to maintain the flooding level desired..

one flooding has established, fores and heads are extracted at rate of 100ml per 10 - 11 min until out the head section (800ml).. at that point I switch to extracting the body section at 3 different extracting rates, as the front section is always the cleanest.. first section is extracted at rate of 550ml per 12 min for the next 4 jars, then at that point in the run I start the compress the extraction rate some, at rate of 525ml per 12 min for the next for 4 jars, at which point I compress the extraction rate again, down to 425ml per 12 min for the next for 4 jars, at which point I now extract the tail section again compressing them..

Over the yrs of doing the same sugar wash ABV, I’ve come to know where the cut points are, and the about run explanation is for a 7 gal run at 40% ABV.. and I'm of the view that the still is there the job I want it do for me, not the other way around, and I'm not an advocate of babysitting a still any more than I have too..

So to answer the questions above, 1) I’ve never notice any different in the finish product quality between the semi flooded and non semi flooded.. what I’ve experienced ease and a time saving of almost 1 hr per run ( from just over 6 hrs to just over 5 hrs).. 2) in the power management there is some adjustment required.. as stated above, I start full power, reduced power at the 150* mark until the vapor breakthrough, them increase power until semi flooded occurs, then I reduce power some to the level required to maintain the required level of flooding during the head extract phase.. In the early section of the body extraction, my power is increase to, again, maintain the semi flooded state in relation to the extraction rates mention.. I maintain the semi flooding required by adjusting the power, so yes there is power adjustment throughout the run, and also in maintaining the same ABV results..

Mars
This is exactly the type of post I was hoping for here. I’m glad you mentioned you noticed no difference in semi vs no flooding; this will help future stillers (and myself) help decide if they want to go this route. I’m realizing the more I frequent this site the more I want to see more definitive places for answers so that new stillers don’t have to do what myself and others have had to do.

So what is your final wattage once you’re at the tails, and what’s your wattage when you start pulling hearts? OR alternatively if you don’t know, do you know the disparity between the start of your hearts and the start of your tails? Mines roughly 4-500 watts; I start hearts roughly 3.5kw and start tails roughly 4kw.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Skál »

I'd have to totally disagree sorry. Creating fluidised beds is the key to SPP anyway. You can get almost identical results but it will take longer and more energy and less clean...so not the same. That's the SPP thing ....efficiency.Surely that translates to lava rock?

I saw you above asking about changing power Cashmere. Never change power input in a spirit run, that's what causes smearing,entrainment etc. Take off,coolant etc won't affect shyz really so use them to control and pick your power input before you start. But...never change power input unless you want half an hour equilibrium.

Read some more above. Yeah guys 'fluid beds at the top and bottom are KEY!' You can take aezo easily without the top of column flooding. Absolutely possible but you won't take 3litre per hour. Perhaps same abv but wait 6 hours instead of one. Same as a high abv boiler charge,my stats are from a wash /mash. BTW this is a 2" column! Try for 3.5lph tomorrow

Fluidised beds are essential for EFFICIENCY and SPEED...not PURITY. My cats hairballs given a copper coating will give you aezo! SPP or knowledge of reflux just lowers times. Reflux my only 'true knowledge in stilling' . Flood IT...if youve gotta do SHIT! Save yer time!

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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Oatmeal »

My last nuetral run settled in with the fluidized bed at the base of the column. This is on a 42" lava rock packed column above a 6" bubble plate. It was very stable. When I've tried to run with flooding on top of the packing it took way more tweaking.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Bushman »

I run a 4” x 48” column with copper mesh. I heat up until I get close to temp then I cut it down slightly until I reach equilibrium. When I am ready to collect every thing is controlled on my CM by the amount of water throw at my dephlagmater. Since I have a stainless steel column without site glasses it is harder to see but I do not want flooding however I feel while running it at the beginning with 100% reflux I do soak my mesh fairly well before collecting. Once starting the collection the temp gauge never changes but all is controlled by how much coolant I throw at it.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by MereCashmere »

Skál wrote: Tue May 17, 2022 9:17 pm
Skál
So in order to keep the flooding you just close the valve more so more reflux is returned to the packing? Doesn’t that mean your takeoff rate slows?

During a run I find that as I take off product the fluid bed obviously shrinks then disappears as I’m taking off, so I raise power a bit to keep it at the top of the bed.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Salt Must Flow »

MereCashmere wrote: Wed May 18, 2022 6:12 am
Skál wrote: Tue May 17, 2022 9:17 pm
Skál
So in order to keep the flooding you just close the valve more so more reflux is returned to the packing? Doesn’t that mean your takeoff rate slows?

During a run I find that as I take off product the fluid bed obviously shrinks then disappears as I’m taking off, so I raise power a bit to keep it at the top of the bed.
The input power determines the amount of vapor and the speed the vapor rises up the column. You can measure the amount of reflux at a given power input by turning off the reflux condenser, plug the top of the column, let your product condenser knock down what exits and measure the collection rate. A VM still should have the valve wide open. Now you know the rate/amount of reflux you produce at a given power input.

Reflux ratio is determined by the rate you take-off in relation to the amount of reflux at a given power input. The faster your take-off rate, the lower the reflux ratio. Slower take-off creates a higher reflux ratio.

You can increase your reflux ratio by either reducing your collection rate or increasing power.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by MereCashmere »

Salt Must Flow wrote: Wed May 18, 2022 6:47 am
Understood… however I know there is a couple schools of thought regarding the process of keeping a fluid bed, and that’s one of the things I hoped to get more answers to in this thread. Either;

1: people reduce takeoff, thereby increasing reflux and reducing takeoff rate, to retain fluid bed

Or

2: people increase power, thereby increasing reflux and keeping takeoff rates the same to retain fluid bed
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by StillerBoy »

MereCashmere wrote: Wed May 18, 2022 9:08 am
however I know there is a couple schools of thought regarding the process of keeping a fluid bed, and that’s one of the things I hoped to get more answers to in this thread. Either;
For me, a fluid bed at the top of packing, indicate the optimum balance of refluxing/equilibrium occurring within the column, provided the fluid level is maintain within a constant range above the packing..

Keeping the fluid level constant above the packing requires, requires being properly setup to be able to manage the power within tenth of amps being used and constant adjustments, and not assuming the that the power supply coming into a house is constant..

It is not uncommon to have power supply fluctuation, and they occur due in part or a combination of, day of week, time of day, position on the line supply, and how much power is supplied the line by the supplier, as I've experience on a consistence level my power supply fluctuating between 236 - 244V.. these fluctuation, as small in number as they may be, will affect the vapor production and behavior within the column, and to some extent affect the equilibrium within the column.. and these fluctuations can only be detected by observation (the use of a sight glass), and can not be properly determine by sound.. also we build controller using cheap components that also have fluctuation range within them, when combine together requires additional attention..

The best way to learn about fluid level and how to maintain them is by operating a plated unit should as a flute.. a flute is operated in large part by the observation of fluid levels on the plates, and that where I come from, operation and observation of the plate fluid behavior, and transferred the learn behavior across the packed reflux columns..

As to the quality of a product, it's not a still issue but a wash issue, as all reflux column still do basically the same thing, extract the alcohol from the water.. once 95% is achieved, that does not mean that you have no flavor in it, it only means you have achieve 95% alcohol.. with our limited column length that the best one can do, as to achieving purity, one need to use a much longer packed column (if one has the room a six foot column).. but the 95% achieve does not means it's shit..

Mars
Last edited by StillerBoy on Wed May 18, 2022 12:30 pm, edited 1 time in total.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by MereCashmere »

Skál wrote: Tue May 17, 2022 9:17 pm Never change power input in a spirit run, that's what causes smearing,entrainment etc.
Skál
StillerBoy wrote: Wed May 18, 2022 10:21 am
Keeping the fluid level constant above the packing requires, requires being properly setup to be able to manage the power within tenth of amps being used and constant adjustments, and not assuming the that the power supply coming into a house is constant..

Mars
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Here’s what I’m now curious about. In my experience I think raising the power level DOES cause entrainment and the mixing of fractions.

This leads me to think two things; do we have to re stabilize/ equalize the column every single time we raise the power to re stack the column?

Or

Do we just say screw the fluid bed, and run just under it as many on the site now do, and get the same product in the same amount of time? (Since they don’t have to constantly re stabilize/ equalize the column)
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Salt Must Flow »

I'm not saying I know something with absolute certainty, but if I step up my power, I'll close the VM valve, step up the power and watch the vapor temp for a while to ensure that everything is stable before I open the valve back up. It's just standard operating procedure for ME. Same if I reduce power. I doubt that tiny adjustments would make any noticeable destabilization.

I imagine those that have many thermometers every so far apart throughout their column would be able to determine if this "destabilization" occurs or not.
Last edited by Salt Must Flow on Wed May 18, 2022 12:50 pm, edited 1 time in total.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Andrew_90 »

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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by kimbodious »

The purest product at the most efficient rate came from my 2” CCVM reflux column (packed with SS scrubbies) when I ran it with a 1” fluidised bed at the top of the packing. I totally agree with Mars about the degree of control required at the power controller to achieve this.

Speaking from experience, adjustments ie increases in power level, were very slight so no need for any period of equalisation to re-stabilise the column.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by MereCashmere »

Andrew_90 wrote: Wed May 18, 2022 11:23 am This looks interesting.

https://www.emerson.com/documents/autom ... kwMTUzNy4w
Well I guess that’s that then LOL

Has this been posted on HD before?
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by StillerBoy »

MereCashmere wrote: Wed May 18, 2022 10:51 am Here’s what I’m now curious about. In my experience I think raising the power level DOES cause entrainment and the mixing of fractions.

It will happen only under extreme mismanagement of power, but not under a controlled setting, or in other word, having the unit dial in..

This leads me to think two things; do we have to re stabilize/ equalize the column every single time we raise the power to re stack the column?

Not required if minute adjustment are made during the run..

Or

Do we just say screw the fluid bed, and run just under it as many on the site now do, and get the same product in the same amount of time? (Since they don’t have to constantly re stabilize/ equalize the column)

I would not support that statement, cause efficiency is lost in the operation of the unit and time of run.. inexperience at running a still is the cause for that statement.. once experience is gain at understanding the unit being operated, as each unit will operate a slight different, and understanding what happens inside the column, only then will the statement make little sense..
Over the yrs, I've experimented with different packing and their effect/behavior in the column.. the setup use for that was a 4" glass at the base, another one roughly midways in the column and my regular 2" round slight glass at the top, and using different power setting and condenser control.. all packing used, the vapors behavior were very similar, but that statement is some what deceiving, due the nature of how the packing itself is packed in the column.. SPP is highly regarded as the best, but not in my view, as lava rocks will do just as well if not better.. why would I make that statement.. because SPP require hardly any compressing went loading them in the column, whereas, lava rocks need to size properly and highly compressed during loading them to get maximum efficiency from them..

There is also the issue of temperature of the condensed distillate coming down and interrelating with the fluid levels at the top of the packing, which should be maintain at a constant temp level, which does have an effect to some degree..

Many little details that are never talk about in the learning of stillin, so as to not discourage a beginner, but as one progresses, are somewhat required to be learn in the name of efficiency..

Mars
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by StillerBoy »

Andrew_90 wrote: Wed May 18, 2022 11:23 am This looks interesting.

https://www.emerson.com/documents/autom ... kwMTUzNy4w
The article has no relationship with what this thread is about..

From the article: Flooding is a common abnormal process condition wherein the distillation column stops generating a separation, thus causing the quality of the top and/or bottom products to go off specification.

This thread has nothing to do with flooding per say but is all about fluid level at the top of packing, very different in behavior.. Flooding occurs went lack of understanding of the process and or lack of indicators advising to assist in the process..

Mars
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Skál »

I won't use the quote thingy to link everyone's comments (too many) but here is my understanding (right or wrong) from when I started distilling using SPP and most of my 'rules' or how I run my still pertain from Odins posts and what I learned there. Currently I'm testing my SPP to its limits, trying to find the very optimum parameters for its use in order to make simplified post for new distillers (SPP USAGE POST) I can only write my results from my experience but I've tested all results twice.

*I won't write " in my experience" constantly just understand that's what I mean.

1: A fluidised bed top and bottom of the column increases purity and take off speed. You can get similar results without obvious flooding ( keeping a visible flood level in sight glass at top of packing but it IS more efficient with the flooding)

2: The second you change power input into a reflux column you cause entrainment. You mess up the stacking. Great analogy is (bullet shot into a fish tank). Although with the caveat of a large boiler charge greater than your column volume minus reflux medium used this might/might not matter but pretty sure I'd does. If anyone wants to work that volume out well done but I can't be fecked. Certainly with a 23L 10% wash, when I've experimented, changing power tails come through.

3: To maintain a fluidised bed I use solely (mostly) take off rate, dialling back the output valve. I say mostly as sometimes I increase the input to my reflux condenser to cool the alcohol further which seems to promote the flooding. This might have another explanation but super cooling the vapour increases the flooding.

I think I've commented on what I can. I'm running a 120cm (filled column) Boka with 5.5mm SPP from Piotr Lipski. Currently experimenting to find the very most efficient way to run it. Managed to get it to 3.5 lph tonight using a 10/11% 80 ltr wash, stripped half to aezo then added to remaining wash and ran it (50L keg boiler). Certainly can get 'similar' results without flooding but when I have take off, and purity not % (purity being subjective) suffers.

Not really relevant to this post but I'm almost convinced now that with 100 cm plus of SPP filled column slower take off (I mean power input plus low take off to isolate nasties) is a hinderence and not efficient at all although counter intuitive. I find that a slow initial take off will compress 'heads fores' and that's great. But, afterwards its not as simple as just upping the power and starting again, it appears to go PAST entrainment. The SPPs ability to hold so much heat makes seems to make a complete mess of the stacking throwing tails up where I didn't want them and 'equalization' is a PITA, longer than an initial 'equalization'. Seems counterintuitive but yeah that's what I found. Almost sure now that sticking to your chosen power input then managing by take off rate is the key (with SPP) and managing the run by take off alone ( caveat of inducing super cooling using input to reflux condenser ) is the key.

Long winded post sorry guys but hope its of some use. On a better note I'm chuffed with tonight's experiments, 3.5lph aezo from a 2" with 7 or 8 L alcohol in the boiler. Pretty sure I'm hitting the very limits of my rig now unless I can get a 45L 40% charge before drinking it.

Great post Mere Cashmere and everyone else's contributions. Really interesting reading especially especially (for me) Sitllerboys using power input to control his run. Gimme a shout if i can do some experiments that could help anyone here regarding similar queries. I might be doing them anyway and if not its still fun.

Skál

Also...LOVE some criticisms here or on my (SPP usage post). I'm not easy offended and that's the point of this site. Science isn't science unless repeatable .

Edit here: my experiments have been for pure aezo

Edit #2 Stillerboy do you not find changing your input fecks up purity (as opposed to %) ? Not sure if you're on 120V or 240V or your elements so that's a 75% difference in power input. Understandably that's a HUGE difference. You don't find tails sneaking etc? Your other data regarding flooding seem to match mine though (can be done but not as efficient).
Last edited by Skál on Wed May 18, 2022 10:31 pm, edited 4 times in total.
Andrew_90
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Andrew_90 »

I took something different from the article. Looking at the two diagrams the first shows how the vapor is moved from the bottom to the top of the column without being interfered with by the descending product allowing for the reflux process to happen. The second picture shows how the vapor struggles to rise to the top and is impeded by excess descending product. This interaction increasing smearing etc.

When I look at my CCVM in operation, the bubbling occurs at the top of the column and is visible to the naked eyes. In deed this was my measure for balancing the energy input. If this bubbling on the top is not controlled correctly, it can lift to the top of the sight glass. I had always wondered about this as my crude understanding of a column operation is that there the vapor rises to the top, gets condensed by the RC and then drops back down to be reheated and to repeat the cycle. Eventually when the ethanol particles are light enough and have shed enough of the "wash liquid" the ethanol then passed into the PC and is condensed.

As the top of my column was bubbling, this to me meant the pressure of the vapor had to fight its way past the descending product and that there was no easy path for the vapor to rise up to the RC. So I believed that my column was flooded, but as I was getting 95/96% ABC by hydrometer I dismissed this as my lack of understanding, I am reconsidering.

So last night I was wondering if I should not remove my sight glass from below the T Piece and send it to the bottom of the column and see what was happening down there.

So the article asides, should there be an uninhibited flow of vapor or should the vapor be fighting it way past descending product. Or perhaps alternately put, should the vapor be rising under convection or by pressure. It is the pressure that causes the bubbling.

Perhaps this post should be posted as a new thread?
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Skál »

Andrew_90 wrote: Wed May 18, 2022 10:23 pm I took something different from the article. Looking at the two diagrams the first shows how the vapor is moved from the bottom to the top of the column without being interfered with by the descending product allowing for the reflux process to happen. The second picture shows how the vapor struggles to rise to the top and is impeded by excess descending product. This interaction increasing smearing etc.

When I look at my CCVM in operation, the bubbling occurs at the top of the column and is visible to the naked eyes. In deed this was my measure for balancing the energy input. If this bubbling on the top is not controlled correctly, it can lift to the top of the sight glass. I had always wondered about this as my crude understanding of a column operation is that there the vapor rises to the top, gets condensed by the RC and then drops back down to be reheated and to repeat the cycle. Eventually when the ethanol particles are light enough and have shed enough of the "wash liquid" the ethanol then passed into the PC and is condensed.

As the top of my column was bubbling, this to me meant the pressure of the vapor had to fight its way past the descending product and that there was no easy path for the vapor to rise up to the RC. So I believed that my column was flooded, but as I was getting 95/96% ABC by hydrometer I dismissed this as my lack of understanding, I am reconsidering.

So last night I was wondering if I should not remove my sight glass from below the T Piece and send it to the bottom of the column and see what was happening down there.

So the article asides, should there be an uninhibited flow of vapor or should the vapor be fighting it way past descending product. Or perhaps alternately put, should the vapor be rising under convection or by pressure. It is the pressure that causes the bubbling.

Perhaps this post should be posted as a new thread?
Andy i'd say no. A flooded column typically refers to the top and bottom being flooded. Being totally honest I can't remember the physics why but only the top and bottom are in a fluid state. Rough example 100cm column roughly 15 to 20 cm flooded top and bottom. I have NO citation for this but it's a rough figure stuck in my head from hours of reading before I bought SPP 10 years ago. Anyhow only the top should concern you in a reflux column. Hope that helps.

Skál

Are you using SPP? My understanding is that the flooding at the top is the only 'measuring' factor. Regardless of what's happening at the bottom the top is the outcome or 'output' indicator. You can bite a donkeys bollocks but him taking you to bed or kicking feck out of you are different outcomes. Forget the donkey teeth see what happens.
Last edited by Skál on Wed May 18, 2022 10:48 pm, edited 1 time in total.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Andrew_90 »

Using 0.25" Raschig Rings.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by shadylane »

For neutral, I do strip runs, dilute then redistill with a packed column.

Anyway, here's how I'd do a 1 run and done with my column.
Max boiler power is limited to the wash wanting to puke, I figure 90% of that power is good.
The take off rate is adjusted for what I want out the spout.
There's a fuzz of boiling alcohol on top the packing, but nothing I'd call flooding or even semi flooding.
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Skál »

Andrew I've read your post 3 times now and I'm pretty wrecked. The bubbling (from what you've written)is good. You have a reflux medium (please state what) in your column that is promoting flooding (great if used correctly).

Your impeding/expeding comment IS distillation! That's how alcohols are purified! That's the basis of a reflux column. Simplified (a footballer has 1000 balls to kick upwards 500 are 500g 500 1kg 500 1.5kg 500 2kg. He boots them all at 50 per second in a tube. Which stay at the top? Gravity decides!

There is NO pressure in a reflux column! Or any still. You WANT reflux (up and down by your parameters ) to make good alcohol.

Perhaps your English lets you down. I've tried to answer but I think your questions are more a language barrier?

PM out of this thread if you need advice

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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by Skál »

shadylane wrote: Wed May 18, 2022 10:57 pm For neutral, I do strip runs, dilute then redistill with a packed column.

Anyway, here's how I'd do a 1 run and done with my column.
Max boiler power is limited to the wash wanting to puke, I figure 90% of that power is good.
The take off rate is adjusted for what I want out the spout.
There's a fuzz of boiling alcohol on top the packing, but nothing I'd call flooding or even semi flooding.

BINGO...do you touch power input? Or have u in the last?
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Re: Semi- fluidized bed/ semi- aquatic state/ semi- flooded Etc.

Post by shadylane »

The power and/or take off rate are adjusted as needed during the heads and foreshots.
Once the hearts begin, I normally don't make any more changes.
The take off rate will slowly decrease as the boiler runs out of alcohol and the tails appear.
Last edited by shadylane on Wed May 18, 2022 11:19 pm, edited 1 time in total.
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