LM modifications to increase speed

[astronomical]

I've seen people boast of numbers close to a gallon an hour at 95% with a 2" LM. I'd like to get a bit closer to these elusive numbers. Please tell me what modifications I can do and explain a bit about how to do them (or please link to an in depth thread).

[astronomical]

I have considered centering rings but I don't know exactly how to go about making them, and, the ferrules make my column 1/8" "thinner" at the ends, so, I cant slide anything in that hugs the walls. Solutions?

I thought about buying some SPP. What kinda increase, if any, should I expect in speed?

[Odin]

The maximum I heared is like 3 liters per hour on a 2 inch LM. In order to achieve that kinda speed, you need to put a bubble ball (inline thumper) in between your boiler and column. The thumper presents the tower with a higher abv, so it has less work to do to get you to 95%. Take off speeds can be increased. Off course positive feedback would enhance things further ...

SPP: a varied story. I guess it increases speed. That's what most claim. You might find yourself facing a column that allmost rocks. Semi fluidiced bed, less vapour space in the column (in comparison to scrubbers), a bigger mass in the column and more power being thrown at it ...

Odin.

[Prairiepiss]

I don't know of anyone claiming a gallon an hour yet? LWTCS is shooting for 4 lts an hour with his new still. Since LW set the mark high I guess that's what I'm shooting for with my bubble bumper Fu Man. But so far the most promising mod for a 2" packed column is a inline thumper of some sort. But the numbers are still up in the air on how much increase to expect. We haven't had enough experimenting and data to say yet. I can say with mine it has increased it dramaticly. But I haven't dialed it in yet. And I haven't tried everything I want yet. Addition of the new heat controller and soon to be new reflux condenser. I will be in a much better spot to get better information.

But the testing I have done. I can get 94% from a 8 gal wash at 10% run was only 5 hours. 12" packed cm on top of Fu Man. It would have taken me at least
10 hours before. I don't have my note in front of me. But you can find my bubble bumper thread and see what I've got so far.

[astronomical]

You think I could achieve similar results by just tossing my boka ontop of my thumper and using its heat source? no return line from thumper... just slow down main boiler and heat thumper directly


im gonna give it a go

[Odin]

What you need is no return line from thumper to boiler. What you need is a draw off line from the top of your column to your inliner. Like that you will be feeding it with 95% pure, thus creating positive feedback.

I just started a thread called something like Odin's Ultra Pure Turbo Non Plus Ultra Distiller. To make some jokes. But actually the technology behind it is serious. At least to the fact that this is how I am going to give it a try.

Odin.

[Prairiepiss]

I think a boka on top of a conventional thumper is a good idea. I actually have been wanting to try it. I'm building one of my brew keggles to double as a thumper. For many reasons. But this is one. The only problem I see may hurt this idea. Heatup time for a separate thumper. It will be more then a smaller inline thumper.

[astronomical]

I think a boka on top of a conventional thumper is a good idea. I actually have been wanting to try it. I'm building one of my brew keggles to double as a thumper. For many reasons. But this is one. The only problem I see may hurt this idea. Heatup time for a separate thumper. It will be more then a smaller inline thumper.

My thumper has its own heating (a hot plate)... When I did tests in the past, it came off at a lower abv when i ran the hot plate during heat up. This tells me that a longer heat up time will result in a higher starting abv. Sounds to me like a longer heat up time could be beneficial. I'll be feeding the packed column with higher abv if i let it heat up slowly. Don't ask me why it does this. Perhaps its teh deeper liquid mass it must traverse. Regardless, the difference was 5% or more.


Im going to take 12 gallons of feints and fill the boiler up and fill the thumper to the minimum level. I'll bring her to a boil and when the thumper is going and i begin equalizing i'll flip on the hot plate and drop the main boiler input considerably. From there it will be pretty hands on trying to figure out teh sweet spot. I wonder if changes made to the main boilers heat input will be slightly "muffled" and have less effect on equilibrium (small changes). Should be fun. Maybe it'll work great. Well see.

[Odin]

Mr. P,

I would go for an inline thumper. With bubble caps or perforated plate. And a colum with on one side a LM take off valve and tube. On the other side a VM take off with a Liebig.

Power up, find equilibrium, draw off heads with the LM (great for heads compression & take off). Shut off the LM valve, clean the tube. Reconnect it to the LM. Only this time the lower take off tube doesn't hang above a collection vessel. Instead, it leads right back into the inline thumper. Thus creating positive feedback, high ABV, rock steady. Open the VM take off and start collecting hearts. Due to the VM operation, tails will be compressed. Actually, when you see your inline thumper getting flooded, you know it is time to stop. O, and SPP for packing.

I feel that in this set up you have all the ingredients: the best heads compression (LM), the best tails compression (VM), the most effective packing (SPP), and the most efficient colum operation due to thumper & positive feedback loop.

To be able to add enough positive feedback, I guess the needle valve on the LM port can best be taken out completely on the hearts part of the run.

My next build? Guess so. Now let's start the first one!

Odin.

[myles]

From what I remember the conventional modifications to Alex's first proposed design were these. (Remember the 1st design was supposed to be easy to build and cheap from commonly available supplies - so the mods were not intended to be critisisms of the design)

1. Increase the column length to at least dia x 20.
2. Insulate the column and the boiler.
3. Use RLM instead of LM
4. Use of centering collars in the packing
5. Increase the diameter of the reflux return line to cope with higher volume of reflux due to higher boiler power.

Also increase the diameter of the product line and valve as SOME users experienced a problem with poor flow out of the smaller dia tube (- various reasons why have been proposed.)

I can't say about No.3, but all the others seem to be logical.

The more recent developments with secondary boilers, spp, vapour reflux etc etc are not included in the above list.

[Odin]

Myles, what does RLM stand for?

Odin.

[myles]

Myles, what does RLM stand for?

Odin.

Reverse Liquid Management. The valve is moved from the product line (- normal LM operation takes some product, the remainder is returned as reflux) into the reflux return line. You regulate the reflux returned and take what is left as product.

I am not experienced with the technique myself, but the starting point is the fact that the volume of reflux condensate decreases with time during the run. RLM is supposed to maintain the volume returned as reflux constant. (With standard LM your reflux ratio decreases as you progress through the run, because the product taken is constant.)

Advantages and disadvantages I am not sure about.

[Odin]

Thanks Myles. Makes sence. Looks to be a pain in the xxx. Contstantly changing that ratio.

Odin.

[myles]

Yes thats why I never realy bothered with LM.

These days I favour a VM/LM combination with LM for heads and VM for hearts. Never realy had time to experiment with ARC, although I suspect VM-E-ARC would be hard to beat.

[thecroweater]

Hi is this what is mean by RLM where a line allows you to return High ABV to the column base should the packing begin to dry/stop refluxing

[myles]

No thats different, this is RLM:

[Oxbo Rene]

I, I, I, just can't see it ..............
Same function as standard Boka .........

[620rossco]

So how fast should a well run 2" boka run and what is possible?
I have read accounts of 12hr runs.
Through the hearts mine did round half a gallon per hour last run.

[Prairiepiss]

So how fast should a well run 2" boka run and what is possible?
I have read accounts of 12hr runs.
Through the hearts mine did round half a gallon per hour last run.

At what ABV was your takeoff? Is this a straight wash or a stripped low wines run?

[620rossco]

Sorry should have been more specific, stripped wash 42 liter charge, 40% low wines.
ABV 95approx. i have a 90-100% hydrometer but need to source a glass tube big enough to fit it.
ABV measured more during the run, but guessing this was because my still doesn't have a liebig and consequently the distillate is over 20deg.
Running the takeoff just below the rate that effects the equilibrium temp and measuring each cut for ABV.
Pulled one heater element after warmup, the other controller was set on about 3/4s- 1800w?
For this still in this situation, 15-20 minutes for a 700ml cut, using ball mason quart jars. Rate dropped toward the end of the run.

So what rate is everyone else getting?

[thecroweater]

Oh ok I was discussing this elsewhere a few days ago where we were talking about LM's slowing down due maybe to theoretic plates drying , as ABV drops and the temp rises affectingly shortening the reflux column . I drew that as an Idea to re wet the plates so as to maintain full column reflux and distillation speed through the tails , haven't really had much feedback on if it would work or not

[Braz]

So what rate is everyone else getting?

I run a 2" Bok. A typical run for me starts with about 30 liters of 28-30% low wines. My takeoff rate is about three drops per second which gives me 400ml in about 50 minutes. A full run is a 13-15 hour effort and net is 5.2-5.6 liters @ 94% after cuts.

[620rossco]

I run a 2" Bok. A typical run for me starts with about 30 liters of 28-30% low wines. My takeoff rate is about three drops per second which gives me 400ml in about 50 minutes. A full run is a 13-15 hour effort and net is 5.2-5.6 liters @ 94% after cuts

Thanks for that. The numbers seem similar, my % was approx and is probably 94% being conservative across the run.
Thinking my faster takeoff can be explained by the extra % low wines in the boiler.

[myles]

With LM you have a single valve in the product line. You decide on a product flow rate and whatever else is being produced by the condenser is returned as reflux.



Reflux ratio changes unless you adjust your product rate during the run. In RLM you specify the reflux return rate, and any surplus is given to you as product.. You do less fiddling with valves.

[Prairiepiss]

Basically a LM your take off and returned reflux is determine and adjusted with the takeoff valve. The less you take off the more reflux return you have. The more you take off the less return you will have.

An RLM your takeoff and returned reflux is determined and adjusted with a reflux return valve. the more you return to the column. The less output you will get. The less you return to the column the more you will take off.

[Dnderhead]

this is like someone flushes while you are taking a shower ,there is just so much vapors and the only way to have more fit up the column it to make it bigger.you can devise ways to remove it faster but this will be at the expense of percent/proof.