Question about a Liebig for a 3" Boka

[sergiolis]

Hi guys,
Before choosing between 2 different options I would like to know your opinion.
My product SS tube ( the inner liebig tube) is 1/2" OD.
I have 2 options for the external liebig tube:

a) with a 24" long sanitary spool tube, 1" OD: The water layer will be 4.3mm thickness

b) I could use a 28mm copper tube longer than 24" if is necessary and the water layer will be 6.5mm thickness

Wich option is the best?
In both cases I will wrap a copper wire and a piece of scrubbie to create water disruption...

Thanks for your help

[Danespirit]

Copper conducts the heat better than steel.
However, for the ease of manufacturing and the looks, I'd go with that spool tube and some tri clamps.
Around 4 mm of water is plenty.
You won't necessarily NEED the copper around the inner tube, don't worry too much about it...the water will find it's way (remember to let it counter flow).
The copper wire and a piece of scrubbie, will be better placed inside the Liebig. It'll take care of the huffing and ensure a smooth output.
Furthermore, it ensures a longer "contact time" as the product runs down on the inside.
How much power will you feed to the condenser...?

[Snackson]

There shouldn't be any huffing at all as the output will be liquid already from the boka head. Are you planning this is a product cooler, rather than a condenser? Sanitary fittings cost a lot more than regular pipe. What I did was take 1/2" stainess tube from the needle valve and ran it into 3/4" pipe soldered through a hole in a cap on the 2" version I built for my cousin.

[der wo]

Are you really using imperial pipes in Spain? Or does 1/2" mean metric 12mm (inside 10mm)?
A thick layer isn't better than a thin layer. For a 12mm pipe I would use a 18mm jacket, if it is available in your country too. 2mm layer is enough. The liebig of my potstill has 1.5mm layer (22mm OD and 28mm OD pipe).
The needed length depends on what you want to do with the still. And the wattage you use (2.5-4kw are ok for a 3" I think). Do you want only neutrals? So 10" will be enough. If you want to run it sometimes without reflux 20" are ok.

[sergiolis]

When I mentioned wrapping a copper wire I wanted to say around the inner tube of the liebig to disrupt the flow.
Yes it is only a cooling product purpose. There will be a boka head with a double helix corrugated SS condenser for vapour.

Hi der wo. As I choosed a 1/2" needle valve the product tube it is also 1/2" OD. I bought it from UK because I wanted to use SS for the product.

For the liebig external tube I bought a 19mm OD sanitary spool tube (24"long) but then I realized that is really thick (1.7mm) so the water layer it will have only 1.7mm thickness. Unfortunately I don't know if it will be enough and I was thinking to buy a new external tube to increase the water layer thickness. It was my mistake because I didn't know the SS spool tubes were so thick.

[der wo]

Stainless steel, ok, I missed that.
1.7mm layer is ok.

[sergiolis]

Der wo if I'm not wrong the 28mm copper tube at least wich I have here in Spain is 1mm thickness, So over a 22mm you have a 2mm water layer..
But 1.7mm will be enough???? It is for a 3" column so maybe my take off will be around 60ml/min....

[der wo]

You are right. It's 2mm... sorry.
1.7mm is almost the same. So I think, 1.7mm is ok.

A thicker layer doesn't increase the cooling power. The only downside of a thin layer is, that if you have to use much water, you get a lot of pressure, so you need more solid water connections. But it's a product cooler, not a condenser, you will not need much water.

What wattage will you use?

[Danespirit]

There shouldn't be any huffing at all as the output will be liquid already from the boka head. Are you planning this is a product cooler, rather than a condenser? Sanitary fittings cost a lot more than regular pipe. What I did was take 1/2" stainess tube from the needle valve and ran it into 3/4" pipe soldered through a hole in a cap on the 2" version I built for my cousin.

Yes, you're right about that.
It was just me thinking ahead...maybe he would like to use this Liebig for other stills too...? (should' have written that in my first reply...my fault sorry)
For a simple and less heavy solution on that Boka you could make something similar to what I build for my LM still: http://homedistiller.org/forum/viewtopi ... 87&t=54834
It is excellent as long as one is dealing with liquid, but I would certainly reach for other solutions when dealing with vapor (as in a VM still).
However, this one represents an inexpensive lightweight solution, that will run fine on a 3" LM still too.
Attached with a stainless compression fitting that resembles a 90-degree angle combined with the angle on the take-off, it doesn't even need support and can just hang vertical from the still.
If you build with what you've got already, you'll need some support to compensate for the weight of the Liebig.

[sergiolis]

I like your opinions, definitely I will try what I have. My main concern is that it has to handle about 60ml/min. or even more on tails because is for a 3" Boka.
Anyway I can try it and if it is not enough I can get a 1" external spool tube instead of 3/4".
In some hours I will upload a project sketch of my design... maybe you can help me to improve some features.
Thanks a lot for your great help.

[der wo]

If the condenser will be really a bit small, the distillate will have 40°C instead of 20°C at full output. There are bigger problems. Theoretical and practical you can run a boka even without any product cooling.

[sergiolis]

Hi guys, this is my project. It is a modular 3" Boka. I will fill it with SPP basically to make neutral.
I tried to coil a double helix reflux condenser and it fits in well but some parts are touching the inner wall of the column... Is that a problem?
I could coil just a single helix if it is a problem.... I think a simple dimroth 12" long can easily hold on 4000 or 4500W
About the liebig I will try what I have because as you say it will work ok.
If you see something wrong please let me know
It is a simple design but I think it will work.... Ohhh I forgot to draw the 1/2" needle valve beloww the elbow!
Sorry, I precisely measure the Liebig and the thickness of the water layer is 1.5mm

[der wo]

-For neutrals a shorter liebig would suffice too.
-Generally a valve with a smaller diameter would be simpler to control for neutrals. Your LM looks more like for flavored spirits.
-The slanted plates don't look good. But I think it's only the hand sketched picture.
-Normally I recommend an external return for bokas. Like bearrivers boka. But if you use it mainly for neutrals, it's not so important I think.
-No thermometer?
-No copper?

Sorry, can't help with the coil.

[sergiolis]

Hi der wo,
the inner diameter of the product tube is 9mm I bought a 1/2" SS needle valve but it looks quite adjustable...
In reference to the slanted plates I have a resized template for 3"...
The Reflux Return is a good idea...
Of course, I forgot to draw the thermometer..
The 3" to 2" Reducer will be filled with handmade Copper SPP.. It is about 11cm height

[sergiolis]

I will figure it out how to build a Reflux Return with vapour block. As I have a sight glass, could I put the reflux return beloww the sight glass? It would be submerged in the SPP.
Hookline says that an external vapour lock in the product line is more necessary than a internal one, but I can't build such a vapour lock with a 1/2" take-off SS tube

[der wo]

I would throw out this fancy sight glass. Total useless IMO.
And if the reflux return is under the sight glass, there is even less to watch. You will only see vapor.

Because you have a product cooler, no vapor lock is needed. But air flow upwards can restrict the product flow downwards at high output rate eventually. Then perhaps a siphon vent would help. But because you will make neutral, you won't use such a high output rate. It's a problem only occurring when using a LM in potstill mode.
So IMO build only the return, no lock or vent.

IMO not enough copper. Perhaps sometimes you build some more of the copper SPP.

[der wo]

Here bearriver is upgrading his LM with a reflux return:
http://homedistiller.org/forum/viewtopi ... 17&t=47184
Similar still for you with a sight glass:
http://www.schnapsbrennen.at/popup/imgW ... age317.jpg" onclick="window.open(this.href);return false;" rel="nofollow

[sergiolis]

Hi der wo,
I was a bit confused about Reflux Return feature... but now i got it...
As this Still is basically to do neutral I won't do that modification. However, is a really interesting feature and defenitely I'm thinking to include this modification in my 2" copper BokaKob because if I want to make flavoured spirits I will do it with the 2" boka.
About using copper I could mix some copper rings too with my SS SPP...
Thanks a lot for the picture, it is really informative...

[rad14701]

Hi der wo,
I was a bit confused about Reflux Return feature... but now i got it...
As this Still is basically to do neutral I won't do that modification. However, is a really interesting feature and defenitely I'm thinking to include this modification in my 2" copper BokaKob because if I want to make flavoured spirits I will do it with the 2" boka.
About using copper I could mix some copper rings too with my SS SPP...
Thanks a lot for the picture, it is really informative...

The reflux return has nothing to do with flavored spirits versus neutrals, it has to do with not overwhelming the upward vapor path at the collection point with descending reflux... My LM head performs much better with the reflux return circuit, eliminating choking within the vapor throat... Whether it is a Bokakob dual slant plate or a dual reducer LM head, there is an increased vapor speed at or near the collection cup so eliminating the need for reflux return to compete with the vapor vastly increases efficiency and overall performance... Searching back through my attachments I'm not finding any pictures of my particular reflux return modification... It was probably the single best modification to my LM head and, in combination with my switch to using marbles for column packing, resulted in a marked increase in sustainable take off rates...

[der wo]

Yes. The return has nothing to do with distilling with or without flavor. But the siphon vent has.
The return also reduces smearing, because the pool is smaller with it normally. And especially with small column diameters it eliminates choking, so you can use more power, and the SPP will mork more efficient. And the temperature measurement works better, because the reflux is more insulated from the temp probe.

[sergiolis]

Hi rad, as you know I'm not an expert and i'm trying to understand some technical issues, but some of them at present are really hard to make up. For instance I read the bearriver post reflux return post about 10 times but is not so clear to me
The other obstacle is my poor english...
I think der wo wanted to say that dealing with flavoured spirits in a boka you must increase your take-off and the chocking problem you mention would be increased compared to a regular reflux run for neutral.
I can understand that using a reflux return you avoid to fill the collecting cup with liquid and you minimise splashing, so you get a real Reflux Ratio. I can see your point too. The reflux return creates a space near the collecting cup free of refluxed liquid preventing vapour choking. Besides that, the refluxed liquid is always completely centered in the column..
I'm building a 3" Boka basically because my runs are too long for the free time I can enjoy. So my main purpose is to increase take-off rate shortening the whole run and I want to use it exclusively to make neutral from stripped allbran worts.
If a Reflux Return is really a well worth feature for my purpose I will include it. Meanwhile I will research more trying to fully understand the whole concept. Really appreciate it!

[sergiolis]

Sorry der wo we posted at the same time...
I started this thread talking about a liebig but then the conversation was diverted. As I need to build a complete 3" Boka I'm sure I will have more questions...
Trying not to be a pain I would like to know if every question deserves a different thread or is it ok if I continue here?

[der wo]

sergiolis,

I don't think, you can get a problem with choking with a 3" slanted plates LM. But with a 1 1/2" concentric LM (I think rad is speaking about this still), choking can be the limiting factor.
And splashing is no problem when you distill neutrals. Because you will never want to run 100% output and 0% reflux.
And the better thermometer measurement is more important for flavored things. Depends on how you want to operate the still.
But a smaller pool is always beneficial. This is the only point you should think about IMO. If you decide to build the still without return, you should ensure that it is easy to upgrade later.

[der wo]

Trying not to be a pain I would like to know if every question deserves a different thread or is it ok if I continue here?

I don't know. The mods will tell you, if you break rules or something.

[rad14701]

sergiolis, it's your build topic so do with as you want... The only real issue would be if another member were to start talking about their build which could cause major confusion...

I'm hobbling around due to a household accident at the moment but will try to get to the basement to fetch my reflux head to take a picture of the simple reflux return I installed...

[sergiolis]

That's great rad!!

[sergiolis]

This is the spool tube I have for the slanted plates and it is only 6" lenght. Even if I decide to build a Reflux Return I don't have enough space. Under this section I will set a sight glass (I know it is not necessary but I like it and I have it). So I think if I want to build a Reflux Return I'd have to buy another spool tube. It means to wait 1 month more because is shipped from China. Maybe my best option is to try it without the RR and if it is necessary I could upgrade it later...

[rad14701]

That's great rad!!

Here you go...

Side view...

Bottom view...

[sergiolis]

Hi rad,
I can't see your slanted plates

[sergiolis]

I could try this: