Still Design/Mod input request

[miletwo]

I know I'm asking for it posting my still design and inviting commentary, but meh... here goes.

Below are some intended mods to add reflux capability to my column which currently identifies as a pot still. Essentially everything for pot still mode already exists but without the center section cut out. I'd be removing that section, adding ferrules, and adding the components on the right for reflux mode.

Any thoughts on the design? Things you'd change and why?

[subbrew]

Couple of questions. Why the tall column (head) on the pot still mode? And the knockdown condenser, why not just a shotgun or liebig? What you show looks like a CCVM condenser to be used with a reflux column. It will not have much surface area in the vapor path so it will not have a lot of knockdown power.

[miletwo]

Tall column mostly so that in both modes they're at the same height... reaching the top of the counter where the collection jars are sitting. In current configuration the boiler sits on a hot plate on the floor and the collection tube sits just about right level on the counter to collect into pint or quart mason jars without much monkeying.

Knockdown condenser (at the final collection area) because that's already the way it's built. I could totally add a shotgun and will likely in the future but wasn't planning for it right away. It's about 12" long in reality and knocks everything that comes off at full boil.

Are you saying the in-line condenser for reflux (dephlegmator) won't have enough surface area? I was planning on that either being wound coil or a shotgun type setup but could certainly increase the size of it if you think that's not big enough.

[Deplorable]

I think you'd be better off building a CCVM and adjusting the height where the boiler sits. Run a short riser(unpacked column) in pot mode with the hotplate on a short table, and a taller packed column for CCVM. You already have the reflux condenser, you just need a shotgun.
I run a 2" CCVM on a 13 gallon milk can boiler. in pot still mode I run just a 15 inch riser to the capped T then out to a shotgun. in reflux mode I add a 20 inch spool and a sight glass. I pack all 35 inches of the column with copper mesh to the bottom of the sight glass under the T, and a 8 inch extension above the T to house the reflux coil. When running as a CCVM if it sits on the floor I can reach the RC without a step stool, but I cant drain the boiler without lifting it onto a stand. In pot mode, it sits on a stand tall enough that I can get a bucket under the drain.

[miletwo]

I mostly do whiskey and rum if that helps. I'm really looking to get a little higher abv and cleaner cuts without sacrificing too much flavor. My thought was that a couple of bubble plates with dephlegmator doing a little bit of refluxing would get me to that state. I know that water temp on the dephleg makes a diff too. Does anyone know if folks usually add a thermometer to them to monitor condenser temps?

[subbrew]

I am rather surprised that the knockdown coil can take down everything at full boil. The picture only looks like it has about 2 inches in the vapor path, with the rest above the path. That is the condenser I was saying did not look up to the job. As far the the reflux condenser I did not have an opinion. Not enough info for that one.

I will second Deplorable's CCMV recommendation. It looks like you already have the parts other than a product condenser.

[Deplorable]

If your primary desire is whiskey and rum, all you need is a CCVM. You can tune the packing to raise the abv if that's what you want, but know that it will also impact flavor because that's what reflux does. It washes the distillate within the column packing removing some of the flavor components.
I fail to understand your desire for a higher abv in rum and whiskey. 80 to 100 proof is all you want for consumption, or up to 125-130P for aging on oak. A pot still will easily give you the abv you need.
A detuned CCVM will get you a light flavored rum.

[miletwo]

If your primary desire is whiskey and rum, all you need is a CCVM. You can tune the packing to raise the abv if that's what you want, but know that it will also impact flavor because that's what reflux does. It washes the distillate within the column packing removing some of the flavor components.
I fail to understand your desire for a higher abv in rum and whiskey. 80 to 100 proof is all you want for consumption, or up to 125-130P for aging on oak. A pot still will easily give you the abv you need.
A detuned CCVM will get you a light flavored rum.

Thanks folks! Helpful feedback for sure.

[stillness]

I agree that ccvm's are rad, but would require a shotgun (some kind of PC). But this is already pretty close to a Nixon stone. Kinda like this thing:

https://homedistiller.org/forum/viewtop ... 3#p6864485

You could skip the dephl, and pipe some of your output back into the column with a valve. Run it in pot mode or some amount of reflux.

My understanding is that bubble plates do better at bringing flavor through compared to packing, with similar hetp.

I'm curious about a 1.5 inch plate. That seems pretty small. What kind of plate are you thinking? Like 1 pro-cap? I think putting in 1 or 2 modular plates isn't a bad idea, but I've not heard much about small bubblers like that.

[miletwo]

I bought these on eBay in a size that matches my column. I debated going from 1.5" (my column size) out to 3" then back down, but the 3" was out of stock and 4inch seemed a bit massive. I figured 2 x 1.5" will be okay for now and perhaps I'll add a few more to the column if I want to do more neutral spirits.

Either way, it will be fun to experiment with.

https://www.ebay.com/itm/323808023276?var=513189097860

[ttocs]

If you're focusing on rums/whiskeys and bubble plates are an option, I'd focus on those. Bubble plates and packing serve 2 different purposes. Reflux packing strips flavor while increasing ABV while bubble plates retain flavor while increasing ABV. Bubble plates are like mini thumpers, infusing flavor into the vapor as it increases ABV.

Plates, dephlag and a shotgun, all being modular is a great setup.

[miletwo]

Totally started over with the design... it means tossing some of the work I did earlier on but I think I can repurpose almost all of the pieces. Here's where I'm at now. Going to start construction after I run off what's in the fermenters currently so that I don't have fermented wash waiting on it.

[Setsumi]

now you are at CM, cooling management and you will need to read up on CM. myself would rather stick to CCVM. but to decide between the different reflux styles you need to understant them....

[miletwo]

now you are at CM, cooling management and you will need to read up on CM. myself would rather stick to CCVM. but to decide between the different reflux styles you need to understant them....

Yep, I get the differences. I chose this route because my intended use is not for neutrals but rather for whiskey/rum and I want as much flavor as I can get coming through but still want to have control over abv and have the ability compress my tails.

Plus, I like building things

I figure with each piece being modular I could totally add a stainless T at the top and different condenser and then packing to switch into CCVM if I really wanted to, but unlikely given I don't really have any interest in neutrals.

[stillness]

Your design with the coiled cold finger is going to need temp / flow rate babysitting, more than a ccvm. Ccvm isn't better suited for neutral vs flavor, just another head style to control reflux ratio.

[miletwo]

Your design with the coiled cold finger is going to need temp / flow rate babysitting, more than a ccvm. Ccvm isn't better suited for neutral vs flavor, just another head style to control reflux ratio.

MMM... gotcha. Thanks! I did order a T at the same time as the elbows so I have it on hand. I'll definitely have to play with running it CCVM.

[ttocs]

You'll be happy with you're updated design. Super capable and also flexible.

Here's my rig with pretty much your exact design. I started with the dephlag route and have no complaints. I went with a T and a cap at the top of my column rather than a 90 so I could use a coil in the future if I wanted to. I don't know that I ever will though. Nice to have anyway as I can flush the column out really easily through the top between runs or similar spirits and not have to tear down to clean.

Another thing to think about it sizing. My bubble plates are 4" but I reduce to 3" at dephlag and then 2" at T all the way to shotgun. The $$ savings add up quick by reducing sizes where it isn't necessary.

[Garouda]

I know I'm asking for it posting my still design and inviting commentary, but meh... here goes.

Below are some intended mods to add reflux capability to my column, which currently identifies as a pot still. Essentially everything for pot still mode already exists, but without the centre section cut out. I'd be removing that section, adding ferrules, and adding the components on the right for reflux mode.

Any thoughts on the design? Things you'd change and why?
Still-design.png

In fact, it's a pity to use a nice reflux coil (your knock down condenser) as product condenser, a Liebig is easy to make and works fine.
What kind of condenser have you as in line condenser?
In a CM mode, you need two valves to regulate your water t°. I'm giving here what I found in Nixon and Mc Caw's "The Compleat Distiller" on page 57...
Cooling management
If you reduce the amount of cooling water fed to a reflux condenser, at some point it can’t condense all the vapour, and some will begin to flow past the condenser. If you do this by design, then the vapour getting past the reflux condenser can be condensed by a second condenser and collected as product.
Consider the operation of the unit in diagram 4-14. Initially, tap A is wide open and tap B fully closed. All the cooling water flows through the reflux condenser, and 100% reflux occurs. After the column has achieved equilibrium, tap B is gradually opened. As more water flows through tap B, less
water flows through the reflux condenser, and vapour begins to pass by without being condensed and returned to the column as reflux. This vapour reaches the product condenser, where it is condensed as product (at whatever temperature you choose!)
Fig. 4-14

We've found that turning just tap B offers more than enough control to reduce the reflux ratio to around 90%, but different stills may have different characteristics. The advantage of having two taps is that control of the water flowing through condenser 1 can be reduced still further after tap B is wide open.
Closing tap A fully when tap B is wide open results in zero reflux, converting the system to a fractionating still or, if the heat input is increased, to a pot still.
This option requires constant pressure cooling water if the reflux ratio is to be kept constant for any tap setting. You can get this by using a small water pressure regulator or by making a small header tank.
Also, the piping for the cooling water has to be laid out carefully to prevent airlocks from forming.

Closing Tap A fully when tap B is wide open will convert your still into a fractionating still if you have some packing material inside the column and as a pot still if you haven't any...
I'm currently running a Ø 3" VM still which gives full satisfaction, but I have a next project a Ø 6" plated column with a dephlegmator hence my interest in Cooling Management. In fact, I plan to use my existing Ø 1" product line which will by definition create some reflux, like in a VM still...
I think the best design for your CM condenser would be a shot-gun like condenser (fire-box like), it's more difficult to build though. In my case I have copper pipes and stainless steel to solder together and I cannot get the right flux down here. I'll go for a coil and compression fittings to avoid that problem.

[Garouda]

If you already have your reflux coil, I would recommend a VM head, you need a T some clamps and gaskets, a gate valve, and you're good to go...

DO NOT FORGET an air outlet in the upper cap!