Enhancing Semi-Flooding Condition with SPP

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sergiolis
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Enhancing Semi-Flooding Condition with SPP

Post by sergiolis »

I would like to ask how we could enhance semi-flooding in a packed column with SPP.
By increasing the height of the column and the amount of SPP we are increasing liquid retention.
It may mean that the pressure buildup will also increase a little and consequently we will need less power to achieve the semi-flooding condition.
I am a bit power limited but I would like to know if there are other ways to reach this condition.
I am also not convinced if a bigger charge in the boiler could enhance semi-flooding too.....
All these factors working with SPP are a bit confusing to me.
Have a nice day!! :)
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Re: Enhancing Semi-Flooding Condition with SPP

Post by StillerBoy »

sergiolis wrote: Tue Sep 20, 2022 7:14 am would like to ask how we could enhance semi-flooding in a packed column with SPP.
By increasing the height of the column and the amount of SPP we are increasing liquid retention.
As an advocate of running a reflux column in the semi flooded state (SFS) with experience in both SPP and lava rocks, but I would need more info before providing further info on it..

What is the column size and length and style of reflux column setup are you asking questions on.. what is the power availability gas, 120V or 240V or something in between as you're in Spain.. and do you have a good source of water availability and flow...

And a large boiler charge has no bearing on the running in SFS, cause it is manage by the amount power used.. also best done using a sight glass at the top..

Mars
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Re: Enhancing Semi-Flooding Condition with SPP

Post by sergiolis »

Hi StillerBoy,
I'm trying to update my system from a 3.5" column (85mm ID) to a 4" column (103mm ID)
I work with LM Bokabob, both of them. My limiting power is 13Kw (240v).
The 3.5" column packed with 130cm with SPP is working nicely with 9Kw and I can see bubbles (liquid boiling or SFS) near the top of SPP through a sight glass at this power.
But I cannot get it with 4". Same SPP (4.2x4.2x0.24mm), same boiler, same boiler charge, a bit less packed height of 120cm. I suppose many factors are involved. I shot 12 or 13 Kw testing the column but couldn't see a SFS. Probably I need more power.
But as I know there is a formula which states that power is proportional to the square diameter of the column. In my case it's not true.
From 2" to 3" I needed 1.55 times more power (from 2.6Kw to 4 Kw). It was reasonable.
From 3" (72mm ID) to 3.5" (85mm ID) I needed 2.25 times more power, in other numbers, from 4kw to 9kw. This disproportion makes me think of some aspects beyond me. :crazy: Should be much more factors because the proportional law doesn't exist to me.
Just wondering if there are more ways to enhance SFS if you don't have enough power or you want to save some electricity.
I would love to see my 4" pipe bubbling...... Thanks for your quick answer :)
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Re: Enhancing Semi-Flooding Condition with SPP

Post by StillerBoy »

sergiolis wrote: Tue Sep 20, 2022 3:30 pm But as I know there is a formula which states that power is proportional to the square diameter of the column. In my case it's not true.
From 2" to 3" I needed 1.55 times more power (from 2.6Kw to 4 Kw). It was reasonable.
From 3" (72mm ID) to 3.5" (85mm ID) I needed 2.25 times more power, in other numbers, from 4kw to 9kw. This disproportion makes me think of some aspects beyond me. Should be much more factors because the proportional law doesn't exist to me.
I would forget about the formula, as it's just good for info, as you have already experience..

From what you have stated, and from what you also have stated about using your full power available, you are still short of the necessary power required to get to the SFS..

There was a post a few days ago on something similar about not enough power to make the column work properly, in that case it was from 4" to 8".. power is the magical answer unfortunately..

As to doing something to get it to SFS, one could try some highly compressed ss scrubbies at the base for about 4 - 6", and see if the restriction created will cause it to get there..

I'm not a fan of 4' column, as I find that the 2" is a very good all around setup, for a few reason, but the main one I don't like to babysit for more than 6 hrs..

Mars
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Re: Enhancing Semi-Flooding Condition with SPP

Post by Salt Must Flow »

sergiolis, what SPP do you use? Did you buy that Doctor Gradus SPP? If so, which size? Do you know what the specs are?
Last edited by Salt Must Flow on Wed Sep 21, 2022 6:33 am, edited 1 time in total.
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Re: Enhancing Semi-Flooding Condition with SPP

Post by TwoSheds »

I have limited (and moderately frustrated) experience running a semi-flooded column, but given your set up and if you're already topped out on the power input the best thing might be to try to send more of that power up the column.

So if you haven't already, insulate your boiler, including the bottom, and your column where you don't have sightglass. That will at least minimize the energy loss to the atmosphere and put as much power as possible into flooding that column.

And of course there's the question of "how are the results?" Are you getting off flavors through? Not high enough ABV? Is there a good reason you're chasing the semi-flooded condition?

Hope that helps.

TwoSheds
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Re: Enhancing Semi-Flooding Condition with SPP

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TwoSheds wrote: Wed Sep 21, 2022 6:17 am I have limited (and moderately frustrated) experience running a semi-flooded column,
Base on the statement about, how is your power managed, by a single pot or dual..

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Re: Enhancing Semi-Flooding Condition with SPP

Post by TwoSheds »

StillerBoy wrote: Wed Sep 21, 2022 6:53 am
TwoSheds wrote: Wed Sep 21, 2022 6:17 am I have limited (and moderately frustrated) experience running a semi-flooded column,
Base on the statement about, how is your power managed, by a single pot or dual..

Mars
Not sure what you mean 'single pot or dual' but I use an Auber Instruments SSR controller that gives me 1% increments for power input. Even with that I find it fiddly to try to maintain a flooded column and it's easy to chase your tail.

With 5,500 watts I'm able to flood 18" of 3" column with Raschig rings, but that's a lot different from your setup. I'm looking for some SPP but if I can't find it reasonably in the US I'll get more Raschig rings so I can double that packed height for better output.
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Re: Enhancing Semi-Flooding Condition with SPP

Post by Salt Must Flow »

TwoSheds wrote: Wed Sep 21, 2022 7:27 am I'm looking for some SPP but if I can't find it reasonably in the US I'll get more Raschig rings so I can double that packed height for better output.
I've been seriously considering SPP for years, but it's so expensive and most often not sized correctly for 3" columns as I understand it. I'm thinking about starting to make some, ordering 4 lbs of wire, making a mandrel, put it in a drill and just spin long coils to cut by hand over time. It shouldn't take long to make.

Traditional calculations say a 3" column should use .02"-.03" diameter wire. The link to the .035" is the cheapest wire I've been able to find. I figure the extra 5/1,000" extra shouldn't make a noticeable difference, but half the price of the .025" wire I've found.
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Re: Enhancing Semi-Flooding Condition with SPP

Post by TwoSheds »

Can't say I haven't considered making it too. I even have a lathe with great speed control that would certainly suffice to wind it but I can't convince myself that cutting it is going to be any fun at all.
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Re: Enhancing Semi-Flooding Condition with SPP

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TwoSheds wrote: Wed Sep 21, 2022 7:27 am Not sure what you mean 'single pot or dual' but I use an Auber Instruments SSR controller that gives me 1% increments for power input. Even with that I find it fiddly to try to maintain a flooded column and it's easy to chase your tail.
I have no ideal what a 1% increment mean in relation to wattage, but a PID is not the best for distilling, yeah they do work for rough stilling, exactly as you have experienced, but not for fine operation of distillation,.. dual mean dual potentiometer, a coarse and a fine, providing the ability to increase/decrease power by 50 watt at a time, and anything less or more will create control-ability..

Ditched the idea of raschi rings and SPP, and get 3/8" lava rocks, if you are to pack a 3", and be done and set for life..

Mars
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Re: Enhancing Semi-Flooding Condition with SPP

Post by Salt Must Flow »

StillerBoy wrote: Wed Sep 21, 2022 2:37 pm
TwoSheds wrote: Wed Sep 21, 2022 7:27 am Not sure what you mean 'single pot or dual' but I use an Auber Instruments SSR controller that gives me 1% increments for power input. Even with that I find it fiddly to try to maintain a flooded column and it's easy to chase your tail.
I have no ideal what a 1% increment mean in relation to wattage, but a PID is not the best for distilling, yeah they do work for rough stilling, exactly as you have experienced, but not for fine operation of distillation,.. dual mean dual potentiometer, a coarse and a fine, providing the ability to increase/decrease power by 50 watt at a time, and anything less or more will create control-ability..

Ditched the idea of raschi rings and SPP, and get 3/8" lava rocks, if you are to pack a 3", and be done and set for life..

Mars
He's using an Auber EZboil DSPR variable power controller. You can dial it from 1% to 100% power. If he's using a 5500W element then each % adjustment is 55W. It's a really great controller packed with a lot of useful features. Instead of actually varying the power like with an SSVR, it uses an SSR that pulses to vary the power.
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Re: Enhancing Semi-Flooding Condition with SPP

Post by TwoSheds »

Salt Must Flow wrote: Wed Sep 21, 2022 2:53 pm He's using an Auber EZboil DSPR variable power controller. You can dial it from 1% to 100% power. If he's using a 5500W element then each % adjustment is 55W. It's a really great controller packed with a lot of useful features. Instead of actually varying the power like with an SSVR, it uses an SSR that pulses to vary the power.
:thumbup: What he said.

There's a big difference between a PID (on/off over the course of many seconds typically based on a temperature setting) and an SSR run by a purpose-designed commercial still controller (on/off many times a second based on a power setting.)

Mine's a DSPR400 if you want to read up. Overall it's treated me well.
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Re: Enhancing Semi-Flooding Condition with SPP

Post by StillerBoy »

TwoSheds wrote: Wed Sep 21, 2022 3:10 pm Mine's a DSPR400 if you want to read up. Overall it's treated me well.
It's certainly not allowing you what you want the still to do from has been stated.. otherwise you would have manageability..
Salt Must Flow wrote: Wed Sep 21, 2022 2:53 pm Instead of actually varying the power like with an SSVR, it uses an SSR that pulses to vary the power.
Pulsing is no different than running by temp in stilling, both disrupt the vapor behavior..

Each to their own I guess, and the enjoyment the issues created..

Mars
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Re: Enhancing Semi-Flooding Condition with SPP

Post by Salt Must Flow »

StillerBoy wrote: Wed Sep 21, 2022 3:23 pm
TwoSheds wrote: Wed Sep 21, 2022 3:10 pm Mine's a DSPR400 if you want to read up. Overall it's treated me well.
It's certainly not allowing you what you want the still to do from has been stated.. otherwise you would have manageability..
Salt Must Flow wrote: Wed Sep 21, 2022 2:53 pm Instead of actually varying the power like with an SSVR, it uses an SSR that pulses to vary the power.
Pulsing is no different than running by temp in stilling, both disrupt the vapor behavior..

Each to their own I guess, and the enjoyment the issues created..

Mars
You are incorrect. It pulses ridiculously fast and provides smooth and repeatable control not affecting "vapor behavior". "As from what has been stated", you do not know anything about this specific controller, how it works, what it is capable of and have zero experience using it. "From what has been stated" even dual potentiometers aren't even capable of the precision in adjustment as the Auber unit. You've failed your critique on all counts.

You are comparing apples to oranges here bud and you are absolutely dead wrong. PIDs operate based on a set temp. PIDs fire the element at 100% power until the set temp is nearly reached (using a smart algorithm to then pulse as to not over shoot or under shoot the set temp). The Auber EZboil has nothing similar in how it operates.

Once again you're making baseless claims without ANY info to back it up.

Ask yourself this ... how is a PID capable of pulsing so fast that it can maintain 1/10th of a degree F within the boiler with such precision, BUT the Auber EZboil (not a PID) can't pulse fast enough so that it can smoothly VARY the power supplied to the boiler from 1% to 100% power? It is an objective fact that the Auber DSPR EZboil works. It's not even up for debate.
Last edited by Salt Must Flow on Wed Sep 21, 2022 4:22 pm, edited 5 times in total.
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Re: Enhancing Semi-Flooding Condition with SPP

Post by shadylane »

sergiolis wrote: Tue Sep 20, 2022 3:30 pm
Just wondering if there are more ways to enhance SFS if you don't have enough power
Decrease the takeoff rate, so there's more reflux.
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Re: Enhancing Semi-Flooding Condition with SPP

Post by StillerBoy »

Salt Must Flow wrote: Wed Sep 21, 2022 3:58 pm "From what has been stated" even dual potentiometers aren't even capable of the precision in adjustment as the Auber unit. You've failed your critique on all counts.
Maybe.. maybe not.. from all indication, not.. all I know and care about is the setup I got creates no issues, can hold SFS at 3/4" level for an hour, the best indicator for operating a reflux column at peak efficiency..

As to the others, their the one with the issues..

Mars
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Re: Enhancing Semi-Flooding Condition with SPP

Post by Salt Must Flow »

StillerBoy wrote: Wed Sep 21, 2022 4:28 pm
Salt Must Flow wrote: Wed Sep 21, 2022 3:58 pm "From what has been stated" even dual potentiometers aren't even capable of the precision in adjustment as the Auber unit. You've failed your critique on all counts.
Maybe.. maybe not.. from all indication, not.. all I know and care about is the setup I got creates no issues, can hold SFS at 3/4" level for an hour, the best indicator for operating a reflux column at peak efficiency..

As to the others, their the one with the issues..

Mars
Perfectly reasonable reply, but sergiolis has the issue and has yet to reply regarding his SPP specs and his power controller specs. There's variables to consider.

Others who've chimed in are using different packing so while their results may correlate, correlation does not equal causation. Too many variables to consider. In that case we've ruled out the controller as a variable.

I agree that Lava Rock is a really really great packing. I've been using it very successfully and even attempted to go against your sizing recommendation (tried smaller) and found that your sizing recommendation is dead on accurate. I believe the reason people are looking at SPP is because there are people boasting just over 5 lph of azeo using it. Considering the very high cost of upgrading the diameter of a column vs simply investing a fraction of that cost in SPP is a pretty strong temptation. I'm considering it myself only to satisfy my curiosity.
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Re: Enhancing Semi-Flooding Condition with SPP

Post by shadylane »

Salt Must Flow wrote: Wed Sep 21, 2022 4:47 pm

sergiolis has the issue and has yet to reply regarding his SPP specs and his power controller specs. There's variables to consider.
Power and takeoff rate are the variables.
His column and packing are a constant.

If you want more flooding increase the power and/or decrease the take off.
Both will cause more reflux.

Depending on the size of the boiler, max power is often limited by the wash foaming up and puking.
An example would be my keg sized electric pot, with 2 elements, the max a clear wash can take before starting to puke is around 6kw. My 4" column can handle more power than that even at 100% reflux.

Here's how I'd make azeo if I was inclined to and had an accurate way to measure it. :lol:
I'd do a stripping run at 5kw at a piss sized stream. Very little reflux, lots of take off.
Dilute to 40% and do a spirit run at 7.5kw and a slow take off rate.
Last edited by shadylane on Thu Sep 22, 2022 1:47 pm, edited 1 time in total.
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Re: Enhancing Semi-Flooding Condition with SPP

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Salt Must Flow wrote: Wed Sep 21, 2022 4:47 pm Considering the very high cost of upgrading the diameter of a column vs simply investing a fraction of that cost in SPP is a pretty strong temptation. I'm considering it myself only to satisfy my curiosity.
There's an old saying.. " Curiosity killed the cat"..

I've got 3 x 36" column packed with SPP from 7 yrs ago.. used them half dozen times... and haven't been used since.. unless one is producing for a large family, a 2" serve the purpose very well at the hobby level..

The issue is people don't understand vapor behavior, and believe that the SPP will give them the speed and ABV.. but forget that is it's not the packing only that give efficiency, both in time and ABV, but learning to understand vapor behavior and managing it to their benefit..

A well setup 36 x 2", properly size lava rocks (sized by hand not screened), packed properly (by jiggling) so tight that 3/4 stay loaded went the column is turned upside down, power managed with a fine tuner, will do a 7 gal run of 40% in 5 hrs.. that good enough for me as a babysitter..

Mars
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Re: Enhancing Semi-Flooding Condition with SPP

Post by Salt Must Flow »

StillerBoy wrote: Wed Sep 21, 2022 6:03 pm
Salt Must Flow wrote: Wed Sep 21, 2022 4:47 pm Considering the very high cost of upgrading the diameter of a column vs simply investing a fraction of that cost in SPP is a pretty strong temptation. I'm considering it myself only to satisfy my curiosity.
There's an old saying.. " Curiosity killed the cat"..

I've got 3 x 36" column packed with SPP from 7 yrs ago.. used them half dozen times... and haven't been used since.. unless one is producing for a large family, a 2" serve the purpose very well at the hobby level..

The issue is people don't understand vapor behavior, and believe that the SPP will give them the speed and ABV.. but forget that is it's not the packing only that give efficiency, both in time and ABV, but learning to understand vapor behavior and managing it to their benefit..

A well setup 36 x 2", properly size lava rocks (sized by hand not screened), packed properly (by jiggling) so tight that 3/4 stay loaded went the column is turned upside down, power managed with a fine tuner, will do a 7 gal run of 40% in 5 hrs.. that good enough for me as a babysitter..

Mars
But you're not saying what power level (how many watts), what your takeoff rate is or your % ABV. You're literally leaving out ALL of the pertinent info that distinguishes what you are trying to prescribe. See the difference? That's making claims WITHOUT anything to back it up. What is stopping you from simply stating your recorded data? Do you not have these simple and basic records which are fundamental to this hobby?

So exactly what SPP do you have? Exactly what are the specs of that SPP? What is the wire diameter? What are the dimensions? What power did you use? What was the takeoff rate? It's like pulling frigging teeth with you to back up your damn claims. Seriously ... there's a pattern here. You often make claims, but rarely ever back them up with any info. If anyone ever asked the same of me I elaborate and with pertinent data.

The OP has a 4" so stay on topic. He is the one that has the issue.
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Re: Enhancing Semi-Flooding Condition with SPP

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Salt Must Flow wrote: Wed Sep 21, 2022 6:52 pm It's like pulling frigging teeth with you to back up your damn claims. Seriously ... there's a pattern here. You often make claims, but rarely ever back them up with any info. If anyone ever asked the same of me I elaborate and with pertinent data.
The OP, if one has understood what he has stated, has already answered his concern/question..

Some on the other hand, need to be spoonfeed with detail info, demonstrating a lack of understanding about vapor behaviors..

Mars
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Re: Enhancing Semi-Flooding Condition with SPP

Post by shadylane »

StillerBoy wrote: Thu Sep 22, 2022 5:05 am
Some on the other hand, need to be spoonfeed with detail info, demonstrating a lack of understanding about vapor behaviors..

Mars
I know very little about vapor behavior.
Could you elaborate on the subject, maybe give me some "key words" so I can search?
Links to the infor would be great. :thumbup:
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Re: Enhancing Semi-Flooding Condition with SPP

Post by sergiolis »

Hi guys,
So sorry, a bit busy these days...
If you want more flooding increase the power and/or decrease the take off.
Both will cause more reflux.
Even at equilibrium (0 take off rate, 100% reflux) I cannot see the SFS at 12kw... by the way... My issues are only with a 103mm ID column... my 85mm column works smoothly...
I told it before, my SPP is 4.2x4.2x0.25mm
The best performance for SPP is the SFS. Many drops are retained by the packing surface and looks like the magic appears when vapours pass through the droplets formed in the offset turns of the spring....
Flooding depends on power but also on type of packing and contact surface/liquid retention. I would like to change the rest of factors because I cannot change my power limitation. So I could try for instance increasing the density of packing. Thinking on adding 2 liquid distributors just in case liquid is dripping on the walls. Etching my SPP to provide more liquid retention. Putting some tightened scrubbers at the bottom of the column to provide more diferential pressure (not sure if this one is a good solution), decreasing water flow and heat transfer of the condenser to the minimum to maintain vapor pressure. Increasing packed height, etc.... On the list it is also to make an smaller SPP, meaning less void space and more contact surface...
Column is already insulated...
Many people with small diameter columns is worried about flooding and I'm searching for flooding...
Any ideas in this direction?
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Re: Enhancing Semi-Flooding Condition with SPP

Post by StillerBoy »

sergiolis wrote: Thu Sep 22, 2022 4:24 pm Many people with small diameter columns is worried about flooding and I'm searching for flooding...
I'm with you on that statement, wouldn't run a reflux column without SFS and a sight glass..
sergiolis wrote: Thu Sep 22, 2022 4:24 pm decreasing water flow and heat transfer of the condenser to the minimum to maintain vapor pressure.
I don't think decreasing water flow, thereby hoping for an increase in distillate temp will increase refluxing any, and also if the water flow is reduced to much, there is the chance of the vapors over power the condenser and flood over the top if it's a LM or VM..
sergiolis wrote: Thu Sep 22, 2022 4:24 pm Thinking on adding 2 liquid distributors just in case liquid is dripping on the walls.
Adding some form of centering, in my view from experience, will not change anything but create choking, as the vapors will to a large extend push the returning distillate back towards the wall due to the different in temp, with or without the centering.. but then again, maybe that just what you are wanting..
sergiolis wrote: Thu Sep 22, 2022 4:24 pm So I could try for instance increasing the density of packing.
That could have some possibility, as tighter or less spacing between packing particles does cause the use of less power.. the last two run (using 1/4" lava rocks in a 2") by compressing the packing to such that went the column is turned upside down, 3/4 of the packing is retain from falling out.. and experience less usage of power and a faster run overall from previous runs..
sergiolis wrote: Thu Sep 22, 2022 4:24 pm On the list it is also to make an smaller SPP, meaning less void space and more contact surface...
That's an option, providing you are equip to make them yourselves.. but I would be incline to go bigger for a 4"..

Mars
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Re: Enhancing Semi-Flooding Condition with SPP

Post by shadylane »

sergiolis wrote: Thu Sep 22, 2022 4:24 pm
Even at equilibrium (0 take off rate, 100% reflux) I cannot see the SFS at 12kw...
That surprises me, I'd have thought 12kw @ 100% reflux would cause a 4" column to flood.
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Re: Enhancing Semi-Flooding Condition with SPP

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sergiolis wrote: Thu Sep 22, 2022 4:24 pm
Even at equilibrium (0 take off rate, 100% reflux) I cannot see the SFS at 12kw...
OK, you're not flooding at 12kw 100% reflux, and cannot see your beloved SFS.
Under these circumstances that you are unhappy with, what are your current ABV and take off rates/hr?
How do these compare to your previous 3.5" column? Is it greater or less than the 3.5"?

The other way to improve your take off rate is to lengthen your 3.5" column to maybe 150cm or more packed.
You mentioned this in your 2nd post. Did you try this or skip right to the 4"?

Then you might consider a larger size packing material as your theoretical plate count will be in excess of 40. Some would say over 40 plates is a waste. I don't say that, because I really don't know.

You may be at 40 plates already in your 3.5" column and could stand to just go larger in your packing and maybe use more available power to get a higher take off rate at the same ABV.

"bitter" has done some interesting work lately that might interest you.
viewtopic.php?p=7708264#p7708264


BTW: What are the take off and ABV numbers on your 3.5" when conditions are to your liking?
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sergiolis
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Re: Enhancing Semi-Flooding Condition with SPP

Post by sergiolis »

Under these circumstances that you are unhappy with, what are your current ABV and take off rates/hr?
I really don't know. I only tested it 2 times. At same take off rate than 85mm column, this one was unbalanced and temp was unsatable. So it wasn't working fine and I aborted operation.
BTW: What are the take off and ABV numbers on your 3.5" when conditions are to your liking?
At Heads it's 150ml/min, at hearts 180ml/min, 9 Kw for a 85mm ID Column, 130 cm Packed section with 4,2x4,2x0,2 SPP seven points star.
I think a good solution to increase pressure drop to enhance flooding would be retaining more liquid in the column but with no restriction to vapours going up.... but How we could get it??? :crazy:
I don't think decreasing water flow, thereby hoping for an increase in distillate temp will increase refluxing any, and also if the water flow is reduced to much, there is the chance of the vapors over power the condenser and flood over the top if it's a LM or VM..
The idea is to maintain pressure, if you cool more quantity of vapour at the top of the column you are decreasing vapour pressure.. But simultaneously you are creating more liquid and this also maybe helps.... who is the winner of the process i have no idea :D
Adding some form of centering, in my view from experience, will not change anything but create choking, as the vapors will to a large extend push the returning distillate back towards the wall due to the different in temp, with or without the centering.. but then again, maybe that just what you are wanting..
The idea is to put 2 distributors like this one. They doesn't restrict vapour flow but they adress liquid to the center.
liquid distributor 1.jpg
liquid distributor 1.jpg (14.26 KiB) Viewed 1001 times
but I would be incline to go bigger for a 4"..
I disagree, bigger SPP will have more void space and less contact surface (In general less liquid retention) so I think it would be increasing the problem. You would need more watts to get the almost flooding situation...
Think that the key is pressure or differential pressure, but my knowledge of chemical engineering is null :oops:
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Salt Must Flow
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Re: Enhancing Semi-Flooding Condition with SPP

Post by Salt Must Flow »

sergiolis wrote: Fri Sep 23, 2022 3:52 am
The idea is to put 2 distributors like this one. They doesn't restrict vapour flow but they adress liquid to the center.
liquid distributor 1.jpg
That will absolutely work and direct all of the reflux to the center, but I would bend every other petal upward a bit so it creates a wider gap between each petal. Doing that will make it less restrictive to rising vapor. In other words, rising vapor will not be restricted to only rising through the center. It can more easily pass between each petal. Here's a pic of mine, It has way fewer petals than yours so I know yours will work great.
Centering Plate.jpg

I don't curl the tips of the petals downward that much. The tips point mostly straight towards the center and just a slight curl. I do that because it focuses nearly all of the reflux to the very center rather than many individual streams around a circle. That's just my personal preference because I like to see the total accumulation of falling reflux through my sight glass rather than many individual streams.
Last edited by Salt Must Flow on Fri Sep 23, 2022 7:11 am, edited 1 time in total.
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sergiolis
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Re: Enhancing Semi-Flooding Condition with SPP

Post by sergiolis »

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