Vodka Rig

[memetic]

I am almost done reading the Compleat Distiller (one more chapter) and read a lot of great information on this site thanks to you fine people. As I posted in other sections, I am mainly interested in distilling a high quality vodka from local wheat. I coincidentally have all the copper and other materials to build a decent size rig and am eager to get started. So far, I have narrowed it down to the Bokakob 2" slanted plate (mini-still) column. I chose it because it appears easy enough to build and operate for a beginner and there are a lot of instructions/tutorials for it. So, before I start cutting copper, does anyone have any advice? last words? I am willing to put in a little extra work for extra gain, but I don't want to get in over my head and get frustrated either.

Thank you

[rubber duck]

Looks to me like you have it together. It's a good rig and you have a good plan. Your going to run a 48in column right?

[Kentucky shinner]

very good rig. Like RD said go with 48". they are easy to drive and make a great product.

[memetic]

I didn't read anything about 48" (I think the last I read was about 39"), but thanks for the tip (both of you). The longest piece of 2" that I have is 45" long, so unless I couple another piece to it I am at 45". Is it worth the extra 3" to couple another piece on? I have no problem doing it. I have piles of copper, lead-free solder, and torches. But if skipping the extra 3" isn't a big deal...

Thank you.

[rubber duck]

Naa 3 inches is no big deal. A centering ring would be good, I'm not sure if the original design incorporated one.

[memetic]

I was thinking about following along something like this:

http://homedistiller.org/forum/viewtopi ... =17&t=5829

I wish there were better pictures of the coil, but I will figure it out.

[kiwistiller]

Sounds likes you will end up a little on the short side, if 45" has to include your condenser and plates. This isn't a dealbreaker on the design, just something you have to be aware of. You can compensate for a shorter packed height by running with a higher reflux ratio - Just be aware this will mean that at any given purity of output, you won't be able to run as fast as with a taller column.

[rubber duck]

I didn't think about that kiwi, good you caught that. 45in should be the packing length, with the plates and condenser attached to the top.

[memetic]

Thanks. I can fabricate it longer. I have a lot of 2" copper pipe. I just have to union two pieces together. My longest piece is 45" - I can attach any length I need to that. Thank you.

[kiwistiller]

might be a nice idea to make it a slip joint you can get apart, or a triclamp, and then using this as an oportunity to put a centering collar in the column 1/2 to 2/3 the way down.

[memetic]

Thanks everyone for all the advice and help.

I found this about centering collars:

"Channeling and poor contact between vapor and liquid is most pronounced the lower portion of the column and this is the best area to place reflux centering collars. Two collars in the lower half of the column will suffice. The center hole in the collar should beat least 15/16" (24mm) for a 2" column and at least 1 3/8" (35mm) for a 3" column."

Does that sound right? I could take kiwi's idea and make a shorter section that has two centering collars that attaches to the bottom of the packed column. I can even leave 3" free at the top of the centering collar section to get the full 48" of packing as suggested.

Thank you

[kiwistiller]

So are you talking about building a centering section that doesn't have any packing in it?

[memetic]

No, I worded that wrong. I can pack the bottom and top of that piece, but I don't know how I can pack between the two centering collars unless I make another joint. Basically, I would then have two centering sections. I don't mind the extra work, but is that overkill? Should I just build one centering section with one collar (that I can pack the top and bottom of)?

[kiwistiller]

You'd probably be alright with just one 2/3 of the way down, if I had two I'd put one in at 1/2 and the other at 3/4. They don't need to be soldered in, mine just sticks with a little bit of mesh at the sides.

[memetic]

Great, thank you. I greatly appreciate all your help. Can you take a look at my current design (based on your advice) and let me know if everything checks out?

Also, where can I read about the 48" column height (instead of 39") information? I want to know more about the operation and theory behind all this (I did a few searches with nothing). Thank you.

[kiwistiller]

Basically, more height equals more "theoretical plates", and more packed medium for the reflux and vapour to do their crazy mass exchange dance. The impact of this on your run is seen as the purity you'll get at a given reflux ratio (which sort of translates to speed). The reflux theory section of the parent site is a good place to start. Your drawing looks good, but you can't have the packing actually inside the collar, or the column will choke / flood (bad news). You might actually decide that it is desirable to put a join in your column there for ease of access to the collar and also for packing / storage / other uses (you could use the bottom section as most of a pot column, etc). Modular construction is really nice to work with.

[memetic]

Thank you. I was wondering how the "diminishing returns" plays into the 48" height. I remember in The Compleat Distiller something about you reach a certain height and it doesn't pay off to go any taller. How was it determined that 48" was the optimal height?

I am wondering, if I decide at a future date to increase production, can I attach many more of the same design columns to a larger boiler. A big boiler with many 2" columns attached to it instead of trying to build a commercial style column? I could slowly add columns as needed?

Also, I revised the dwg. Check it out and let me know what you think. I think this covers everything you advised. I am eager to get building. I also posted in other sections about getting ingredients. I wasn't able to get any local wheat, as they don't grow any here. I am stuck buying it online. Ugh. I plan to order in the next few days and get going. I am so excited.

Thanks again.

[kiwistiller]

I am wondering, if I decide at a future date to increase production, can I attach many more of the same design columns to a larger boiler. A big boiler with many 2" columns attached to it instead of trying to build a commercial style column? I could slowly add columns as needed?

In theory, but balancing it in practice would be a nightmare. Better to sell the column to some other stiller and build a bigger one when you need it (3").

Thank you. I was wondering how the "diminishing returns" plays into the 48" height. I remember in The Compleat Distiller something about you reach a certain height and it doesn't pay off to go any taller. How was it determined that 48" was the optimal height?

I personally don't regard 48" as the optimal height and would build taller out of preference. The dimishing returns people talk about relate to the phase diagram of an ethanol / water mix. As you can see by the curves, successive redistilations increase ABV by dimishing amounts.
http://homedistiller.org/forum/download ... hp?id=6826

drawing looks good.

[memetic]

What would you consider an optimal height for what I am planning to do? I have no height limitations; the space I have is 16' tall. I plan to stick to my plan for now, but just curios.

Thank you again for your input and help.

[kiwistiller]

There isn't too much point in going past 60". There is material cost to consider as well.

[memetic]

Thanks for all the help. Next time I post about my rig there should be pictures. I am trying to track down a quality source of flaked wheat and crushed wheat malt; I have a couple leads. The plan is to start the mash very soon and build the rig while it does its thing.

Also, I cannot wait to try your gin recipes. I love gin, but I'll get to that after I master vodka.

Thank you

[newerbrewer]

Can someone give me a good explanation of a centering ring?

[memetic]

kiwi, what would your recommended height be for the same design but in 1.5" diameter pipe? I got inspired by your advice on building in a modular fashion and I have piles of 1.5" copper pipe (but only a limited amount of 2"). I think I am going to take a step back and build the 1.5" first. I have read so many posts here about people saying they wish they did this or that the first time, so I want to experiment/practice before I use the 2" copper.

I think I am going to increase the condenser to 7" too.

Thank you

[kiwistiller]

I wouldn't change its height. I don't believe the diameter has much in the way of a practical effect on desirable height, despite the fact that some people like to talk about it in a ratio that implies it does.

[memetic]

One day I hope to understand why it is you know that; it's not just research, I think experience is key, which is why I love forums like this with fine people such as yourself willing to help. I truly appreciate your advice. Thank you.

[kiwistiller]

Not experience from me, no. Just research, theory, and listening to the experiences of others. Most of the equations that govern reflux operation are on the parent site, you can always have a look and decide for yourself
Cheers,
Kiwi

[memetic]

Sure, but I know I'll completely enhance my understanding of the theory behind all this when I have a working still to experiment with. I am good with books and theory, but I really like to have the physical thing in my hands sometimes.

Here are my revised drawings for the 1.5" rig. I put a piece of pipe halfway between the 1/2 way and 2/3 way for the centering collars; that way, I can pull that section out and put one collar up, and one collar down at the locations you suggested. I can always move them around a bit if needed.

My biggest questions are about a couple items I have seen fluctuate quite a bit. They are:

What is the optimal height from the top of packing to the bottom of the upper plate (right above the thermometer inlet)? If there is one, anyway. (Mine is drawn at 3", based on another design.)

Is it preferred to leave the top of the column completely open, or put on a cap and drill a 3/8" hole to atmosphere? Or, does it matter?

Back to cutting copper...

[kiwistiller]

I'll leave the boka specific questions to someone more qualified to answer, but as for the cap on the top, just do whatever makes you happy. There is no 'need' for a cap if your coil rests on its tails or is tight enough to hold on friction alone.

[memetic]

I may skip the cap then.

Here is where I am at. I plan to wrap the column with plastic and slip it into the pvc (centered), then inject (spray in) the closed cell insulation. Then, I'll pull the column out and cut the pvc in half the long way. Then, I'll have an insulated shell that is removable from the column.

I have a girlfriend and kids to play with so I'll have to make more progress Monday. My ingredients will be here early next week. Heehee, having so much fun...

Thanks as always. (I'll be peekin in, so feel free to comment.)

[memetic]

For some reason my new plan didn't upload. Here are the new plans for the 1.5" rig (see the pic above for the actual thing).