Modular CCVM build

[Sk8brew]

I am starting a CCVM build for neutrals, mainly to make gin, and am looking for some advise. I currently have the setup shown below with a 10gal boiler that runs 2800W max on 240V. It has double walls to provide some insulation. My current potstill is a 2" column with a 1" over 3/4" Liebig condenser. I am looking to build a CCVM and would like to make it modular so I can use the PC for both columns. After much research, here is what I am thinking:

The boiler has a 2" cap soldered to the SS lid. From here I will use a 2"-3" reducer to a 3"SS column. The top of the boiler is 32" and the ceiling is 88". I think this gives me room for a 3"x40" column, leaving 16" for a 3" Tee and condenser above the tee. Is this enough?

On the output side of the Tee, I need to reduce down to connect to the Liebig. I could either do this at the 2" region or 1" region prior to the elbow, or to the 3/4" union. I am not sure what length is needed from the takeoff at the 3" tee before reducing down. My plan is to put a tri-clamp fitting in here to make it easy to switch columns (unless I connect to the union). Thoughts?

I posted in another thread, but will put it out here too. I read that for a 3"column, 3000W is needed. My boiler is 2800W. Will this be a problem, or is it still better to go with 3" than 2" to increase output rate?

Thanks for your help!

[kimbodious]

Sounds like a solid plan. 40” x 3” column would be better being a bit longer but you should still get the purity you want maybe by involving greater reflux.

[NineInchNails]

I have a 3" VM with 5' to 5' 6" of copper mesh packed column packed relatively tight. I run my 5500W element at 60%-65% power on spirit runs and take off at an interrupted stream and get 95% and smooth as can be. I noticed if I open it up just a bit more, it comes off with some bite/burn. It's worth while being patient and just run it slow.

[Sk8brew]

2A275F0B-BB2C-475A-ACCD-824609EA7E35.jpeg (31.63 KiB) Viewed 4117 times

I have made some progress on this build and am looking for some more advise. I have struggled a bit with cooling water flow on my pot still and am looking to use something better than either a ball valve or hose bib gate valve. Most of the needle valves I find are 1/4". Will this allow enough flow for both RC and PC (separate valves for each)?
How far below the tee does the reflux condenser need to go?
Should the water inlet of the RC go into the coil first or the straight section first? My thought is you should have the coldest water at the top of the coil, but I am not sure.

For what it is worth, tri-clamp is a bit more expensive, but damn is it easy to build.

[kimbodious]

I don’t have any inline water flow control on my 2” CCVM. The water is routed in through the bottom of the product condenser out through the top and then in to the reflux condenser. My reflux condenser probably on extends last the offtake on the tee by less than 10 cm in full reflux. I hope that info helps?

[NineInchNails]

I use 1/4" OD Polypropylene tubing (for higher temp resistance) and a 1/4" brass compression needle valve. That works just fine and I have no regrets. If I had to do it over, I 'might' have gone with 3/8" OD tubing & valve, but that wound just allow for more flow that I don't really need anyway.

I use the same size hose and same size needle valve to feed my shotgun condenser too. Both condensers are controlled independently of each other. Shotgun condensers do not require much water flow at all. If I were to use a Liebig condenser, I'd probably go with 3/8" OD tubing if I could find some in polypropylene. 1/4" PEX is 3/8" OD and would work good. 3/8" PEX is 1/2" OD, is unnecessarily large, but also has good temp resistance. I like to use John Guest ball valves on both of those tubes too.

[NineInchNails]

I'd consider making a double wound copper reflux condenser. It's a fun project and they work very well. I made mine out of 5/16" OD copper tubing. It has just a tad larger than 1/4". I was concerned larger dia tubing would be more difficult and I could potentially fail in winding and making it fit in my 3" pipe.

[Tummydoc]

Agree with kimbodius, no real need for a control valve to limit flow to the RC in a CCVM. only needed in a CM still.

[Sk8brew]

An update on my build. Here it is in pot still mode:

And in CCVM mode:

[Sk8brew]

Now an update on my first CCVM run. Overall, I am really happy with how it went, but there were some things that happened that I need some guidance on. I started with a sacrificial run of 30% low wines. Started up at full power (2800W). Once the column started heating, I turned on the RC. After a little while when the column was hot up to the take-off, I started getting product out with the RC all the way down. I also started having a leak in the Tee on the take-off side (liquid dripping out of the bottom of the tri-clamp). I tried tightening it up, but it continued to drip. Eventually I also got a drip at the base on the 3"-2" reducer, but it was very slow. After 20mins or so I pulled the coil up and started collecting product. I collected 4 samples of 200ml each and all measured 92%. After this I shut it down.
I disassembled the column, rinsed it with hot water and noticed that the copper scrubbies I have on the RC seemed to be leaving residue. I am pretty sure my "pure copper" scrubbies from amazon are not pure. I took them out and a copper colored residue was dripping off of them. So, I took everything apart and replaced them with SS scrubbies. This was just at the bottom of the column and on the RC. I am using aquarium filter ceramic for the packing. Putting it back together I made sure the fitting faces and PTFE gaskets were clean and tighten them up pretty tight. I also recoiled the RC to try to get more coils in the Tee. I think I may need a longer coil. I have a 60" x 1/2" and a 10" spool at the top. I only get about 3 coils on it and still be able to have it go below the take-off. I put a scrubby in between the coils and above them to help with heat transfer.

Now to the spirit run, about 12L of 35% low wines. Again heated up at full power and started getting some product through with the coil down. No leaks this time. I lowered the power to 70% and increased the RC water flow. That stopped the product flow. I let it reflux for 30mins. I did not hear any sound coming from the column. After 30mins I lifted the RC and started to get some flow. Dumped the first 200ml and then started collecting 300ml at a time. First jar I upped the power to 85%. Measured 92%. Upped the power to 100% and collected 13 more jars at about 2.2L/hr and all measured 92-93%. The last jar I started to smell some tails and flow dropped to 1.7L/hr. After that jar flow pretty much stopped or at least went to a slow drip so I shut it down.

I was amazed how compressed the tails were and the fact that it stopped flowing almost immediately when they came. After reading about flooding, I was on high alert for boiling sounds from the column but the only sound I heard was water flowing through my condenser. As far as output rate, I can pull over 4L/hr in pot still mode, but was limited to just over 2L/hr in CCVM. This is about where I normally do a spirit run for pot still, so it is fine with me. I was also surprised how consistent the 92% was for the whole run, up until the tails hit.

So here is what I think is going on, and I am looking for any CCVM guru's to help me out. My boiler is probably at min power (2800W) to drive a 3" column. It was a cold morning, 40F or so and I didn't insulate the column. The boiler has a double layer (made for all in one beer brewing, so somewhat insulated for the mash). Does my procedure seem OK? Are these results what you would expect? Any advise?

[zapata]

I also have a foundry, it's great for brewing, sees occasional use as a boiler too. But I'm not sure I'd really consider it insulated. If you really want to max the watts coming out the end, I'd insulate it further. It's probably only a couple hundred watts at most, but it's real. Insulating the column, same thing. Not only does it put your power to work, it gets maximum use of the reflux on a relatively short column.

I do not abide a leak. Not a drop. One drop and the clamps get tweaked down. If it keeps dripping I shut down and sort it out. Good to hear you got them sorted.

As far as output rate, I can pull over 4L/hr in pot still mode, but was limited to just over 2L/hr in CCVM.

Well yeah, you're refluxing half your distillate so you get half the product.

[savagedavid]

I am no guru, but I can relay my CCVM experience. I am currently running a 2800W oil jacketed boiler with a 2" x 48" stainless CCVM column. I have an additional 3000W element in the drain port that I only use for fast pre-heating. I use 1 piece of wadded up copper mesh at the bottom and the rest filled with OSPP (I had to have it locally manufactured in South Africa since it is virtually impossible to import). PC is 3/4" pipe around 3/8" tube. CCVM coil is wound 3/8" copper. I run cooling water through the PC and RC inline.

Once I have equalized everything I take off foreshots quite slowly (2-3 drops/second) and once I can no longer detect acetone I speed it up a bit for heads. I usually use a low wine derived from sugar wash so it's pretty clean with little in the way of heads.

I'll then run the unit at the full 2800W and take off around 2.5L / hour at 95% for the entirety of the run. What always amazes me with the CCVM system is even though the cooling water heats up 10+ degrees through the run (it recirculates), I never drop off the 95% concentration.

So in summary 2L/hour seems okay for 2800W of heating just comparing it to my system. Since I only have 2" with your 3" you should be able to double the output with more power. But again, I am no expert.

[Sk8brew]

Thanks, appreciate the input. Next run I will try some insulation and see what difference it makes.

[Sk8brew]

I need some help with this. I have run the same batch of low wines 3 times and am getting very little clean neutral. My setup changed a bit from above. I found that the 10" spool on top was too long for my condenser as I had only a few coils and some product was going over when it was fully down. So, I bought an 8" spool for the top and added the 10" to the column so it is now 3"x46". I am using ceramic aquarium packing from this thread: https://homedistiller.org/forum/viewtop ... 17&t=77413. I am also using a blanket to insulate the column as suggested.

First two runs I ran similar to the first run described above. After fores collection, ran at full power keeping the condenser at 110F in full reflux for 45mins. Then raised the RC and started collecting. Collected 22 jars of 300ml each from ~5 gals of 35% low wines from shady's shine recipe. Rate was ~2L/hr. With the added 10" spool, I was pulling 95% @58F compared to 92% previously. Did my cuts and kept jars 9-19. Mixed it all together and it was not great. Has some tails in it. Decided to redistill and make better cuts. Second run was similar. Went to do cuts, trying to be much more strict and found that there was smearing and only 3-4 jars were clean. It wasn't worth savings as I want to make gin from this and will need a larger batch than that. In a bit of frustration, I tossed all of the stuff that didn't make the cut. So the next run should be cleaner low wines.

So, I went back and read some more and it looks like a lot of people run at very low power in full reflux to stack the column. So I tried this method. My power controller goes by percent. 100% = 2800W. I assume it is linear. Cut power back to 40% once I felt the bottom of the column heating up. It did not continue moving up the column, so I kept bumping it up over the next 20mins or so to get the vapor up the column. Ended at 55%. At this point I raised the RC and lowered the power to 45% until getting 2 drips a second. Collected 200ml. Raised RC more until broken stream and collected 600ml strong heads at 92%. I am not sure why the ABV was lower running this way. It should be the same or higher if I am running slower, right? I did break my alcometer, so was using a different one from the runs before. Hopefully they are not that different. I then raised the power and collected 300ml every 12 mins (1.5L/hr). At jar 16 I detected some tails and the output slowed, so I put it in reflux for 15min then continued collecting. Flow went to a few drips at jar 21, so I stopped. Cuts: Tested jar 12, seemed pretty clean, went back to 10, 9, 8 and heads started showing up at 8. Went up to 18 and back down and nothing seemed clean, even 12 was not great at this point. So again I am left with 3-4 jars of clean neutral.

Any advice on how I am doing this and how I can get less smearing?
Also, I was taking DAD's advice to keep the RC below 120F. In full reflux it was ~100F. When I lifted the RC to start collection, the temp dropped 20-30 degrees. Should I adjust flow to reduce water waste, or just let it run cooler?

[kimbodious]

Sounds like you did not have enough reflux on the last run. You need plenty of mingling between vapour and condensate to get the higher parities. You increase the reflux by increasing the vapour flow rate. There will be an optimum vapour flow rate.

Your “smearing” in the previous rounds sounds more like the result of flooding. Flooding is where lower purity condensate is spilling out the offtake. Flooding occurs when the condensate can’t return to the boiler fast enough so it builds up on top of the column packing until it spills over. One way to reduce flooding is to reduce vapour flow rate. The other way to help reduce flooding is to make sure that things like the screen to hold up the packing is not restricting the condensate return too much.

[Sk8brew]

So maybe run it some where in between where I have so far?

[Andrew_90]

............... and the rest filled with OSPP (I had to have it locally manufactured in South Africa since it is virtually impossible to import).

OSSP?

[bluefish_dist]

If power is too low, then more power can raise the abv. Seems backwards, but what happens is you take off too much and lower the reflux rate. So more power gives more vapor and the reflux rate goes up making a more pure output.

Usually I go for max output, so I am always on the verge of pushing tails up the column. Then reducing power helps as it reduces vapor speed and tails don’t get pushed up the column as much.

[Sk8brew]

I am struggling with getting clean neutral out of this column and am looking for some guidance from those more experienced.

As suggested by Bluefish, I bumped up the power on this last run to get more reflux. Just to the point where I am not getting any product out with the RC fully down. This was about 80% power (~2200W). I can not hear any noises in the column, so I am just assuming if I get product out with the RC down, I am getting liquid too high in the column. My RC water temp is kept <120F. I let it reflux for 30mins and raised the RC until I was getting 2 drips/s. Collect 300mls this way at 95%. Raised the RC until I was collecting 300ml jars in 10-12mins. ABV dropped to 93%. I collected about 14 jars total before the flow dropped off with the tails. Making my cuts, again only a couple of jars seemed clean enough.

Cuts: I get a sweet, flavorful heads after about jar 7 or 8. It is smooth, not chemically or burning/prickly on the tongue. Once this subsides, I start to get a bitter taste I think is tails coming through. Very little of the middle jars are the clean neutral I was looking for.

How can I run the still to compress the heads and tails more?
Do I have enough power (2800W) for a 3" column?
I am using ceramic aquarium packing from this thread: https://homedistiller.org/forum/viewtop ... 17&t=77413. Here is the exact stuff: I don't know if this is good for my column/setup. I don't hear anything in the column, so is it not flooding at all at this power? Does it need to flood to some level? From reading it seems quite a lot of people try to get flooding just below the top of the packing.

I will start a new batch soon in case that is my issue, but I really don't have a good plan as to how to run this now based on my experience so far. Any help is much appreciated.

[Chur]

Sk8brew How much space do you have between the top of your ceramic packing and the bottom of your RC at it's lowest position? I read that at least 60mm is required. I'm just about to start running my CCVM 3" tomorrow for the first time on 50L keg with 5.5kw element and Scoria packing. Hopefully I don't run into the same issues as you are having.

[Boozewaves]

As suggested by Bluefish, I bumped up the power on this last run to get more reflux. Just to the point where I am not getting any product out with the RC fully down. This was about 80% power (~2200W). I can not hear any noises in the column, so I am just assuming if I get product out with the RC down, I am getting liquid too high in the column. My RC water temp is kept <120F. I let it reflux for 30mins and raised the RC until I was getting 2 drips/s. Collect 300mls this way at 95%. Raised the RC until I was collecting 300ml jars in 10-12mins. ABV dropped to 93%. I collected about 14 jars total before the flow dropped off with the tails. Making my cuts, again only a couple of jars seemed clean enough.

Cuts: I get a sweet, flavorful heads after about jar 7 or 8. It is smooth, not chemically or burning/prickly on the tongue. Once this subsides, I start to get a bitter taste I think is tails coming through. Very little of the middle jars are the clean neutral I was looking for.

How can I run the still to compress the heads and tails more?
Do I have enough power (2800W) for a 3" column?
I am using ceramic aquarium packing from this thread: https://homedistiller.org/forum/viewtop ... 17&t=77413. Here is the exact stuff: I don't know if this is good for my column/setup. I don't hear anything in the column, so is it not flooding at all at this power? Does it need to flood to some level? From reading it seems quite a lot of people try to get flooding just below the top of the packing.

I will start a new batch soon in case that is my issue, but I really don't have a good plan as to how to run this now based on my experience so far. Any help is much appreciated.

That packing must work if you can get 95ABV .

if you can get the liquid to boil / product to come out / the outside of the column to get hot up to the tee you must have enough power , I don't flood my ccvm whilst running it . I can still get a few drips output if my reflux condenser is down , thats not because of flooding its just because there is a space for the vapour to squeeze past . as long as you are able to keep the column in almost full reflux with the condenser down thats fine , a few drips the whole time of full reflux is o.k its only foreshots . if you get too much , adjust the scrubbies a bit or add more .I have found holding the column in full reflux for an hour is best for me but different people prefer different ways or amount of time . Dad3000 says to remove heads before full reflux , I want to try this when I start again to see if my best can be better . .

I have a sight glass below the tee on the column , its not 100 percent necessary to have one but it really helped me to understand running the still . there are 3 variables that you can change during a run , there's the heat input , the water flow and the reflux condenser height . being able to see the effect altering any of these has on the distillate dripping off the RC helped me a lot so i'd definitely recommend buying one

from earlier posts it sounds like you are not putting much into the boiler for the spirit run , I put 3 stripping runs worth into a spirit run and add water up to the maximum safe level of liquid I can put in which is 35 litres on mine .having that amount to run makes it easier to do cuts and get a good amount of hearts . it sounds like you are separating well enough if the middle of your run is good hearts .

from that size run I get 10 litres of good neutral/vodka after the hearts are watered down roughly to 40ABV . it did take quite a bit of trial and error as well as reading here to get used to running my still though

[Sk8brew]

Sk8brew How much space do you have between the top of your ceramic packing and the bottom of your RC at it's lowest position? I read that at least 60mm is require.

I have at least 50mm. The only thing I have read about this is to just make sure you don't touch the packing. What is the reason for 60mm gap?


Boozewaves, I have thought about a sightglass, but the height is getting a bit difficult to deal with. How much power do you put in during full reflux? My still in potstill mode can run 4l/h, so if I reflux at full power I will be condensing at least 3l/h. If it is not flooding, is this the best way to separate components?

[kimbodious]

Lower the height of the packing so that it say 150mm below the bottom edge of the offtake. This will reduce the risk of condensate being splashed or sprayed out the offtake. When you have a sightglass immediately below the offtake you may notice the fairly turbulent interaction between the rising vapour and falling condensate. The bitter taste you are getting is not from tails but from condensate.

[Sk8brew]

Lower the height of the packing so that it say 150mm below the bottom edge of the offtake. This will reduce the risk of condensate being splashed or sprayed out the offtake. When you have a sightglass immediately below the offtake you may notice the fairly turbulent interaction between the rising vapour and falling condensate. The bitter taste you are getting is not from tails but from condensate.

Should I add a scrubby on top also?