Idea for CCVM - Concentric Combo Head

[Kegg_jam]

I been kicking around building a combo head for a while. I guess i haven't built anything for a while and i have the parts around to do it. Does this Idea seem feasible? I know the vapor split is not symmetric.

Pipe size is 1.5" and the concentric is 1.5" X 1.25" X 1".

[bearriver]

VM/LM combos are fun to build and design. Yours looks like it would work.

I don't personally see them as practical. I'd rather build one or the other and then spend the money I saved on other still stuff. VM and LM are both capable of making the same type of spirits. Why spend extra money on having two heads that make same things? It just seems unnecessarily complicated.

[thatguy1313]

That looks like it would work. I like the outside of the box design and thinking! That's what drives this hobby forward!

[RandyMarshCT]

I did it (combo head) so I could keep the VM side squeaky clean of heads contamination until I felt the heads were fully bled off on the LM side. I feel that it does make a noticeable difference.

[Kegg_jam]

I see your point bear.

I have all the parts already. I've migrated my CCVM to 2" from 1.5". So there is an extra 1.5" tee that is largely unused.

The concentric LM and the CCVM both have their strengths but operate very differently. Perhaps it is my lack of experience but the product from both heads when run independently ends up being very different.

[Danespirit]

Your idea should work great..
Only issue i would mention...the takeoff at the CCVM side, should match the column diameter to get a 50/50 vaporsplit.
I don't know how ridgid it will be...you might want some kind of support, so the CCVM section is held in place..?
How would your LM section be..do you have a "roof" over the pipe going up in the condensersection..?
How large do you plan your liquid reservoir to be in the LM section..?
I would make it as small as practical, the smaller reservoir, the less smearing.

[Kegg_jam]

Dane, the two heads already exist and operate well as stand alone units. I do not have a plate or roof in the concentric. I think at some point it was deemed unnecessary in Rad's build thread. I could try one pretty easily. The reservoir does need to be made smaller. I think it holds about 3 ounces but I forget exactly. That's an easy mod too.

The only thing that needs to be made is the crossover pipe to run the CCVM head. I could do it with a regular tee and a 90 but I imagine there would be a lot of pooling in the horizontal pipe.

Thanks for all the suggestions!

[ben stiller]

Keg_Jam, how far does the 1 inch stick up into your concentric condenser? I am running a 1.5x1.25x1 concentric as well and it was a fight to
just get a 1 ounce collection reservoir. I believe mine extends about 4 inches above the reducer.

[Kegg_jam]

...running a 1.5x1.25x1 concentric as well and it was a fight to
just get a 1 ounce collection reservoir. I believe mine extends about 4 inches above the reducer.

Yep, my memory sucks. I was way off. Mine is the same as yours. 4" extended. About a 1 ounce reservoir..

[HookLine]

Can't see that balancing act working too well. I think you will get limited, non-linear, and hypersensitive control, and low output from either path.

Looks to me like one of those designs where you will just end up chasing your tail, and go mad trying to get it to work.

Your aim is worthy enough: Trying to add a separate LM take-off path to a CCVM.

This might work for an LM / CCVM. Not sure how much vertical distance you need between the condensers in LM mode. Will depend in part on how much pressure and velocity the vapour has.

Can also be done in principle as a CCLM / CCVM, but it is not a very practical design, costs too much vertical space – still working on it.

[still_stirrin]

I like that one Hookline.

The LM side would work great for collecting the fores and compressing the heads while the CCVM was in total reflux. Then, just turn the water off to the LM condenser and let the CCVM regulate the VM output.

Plus, keeping the LM branch close to the trunkline will keep the vapor flows (relatively) balanced, at least during the fores/heads portion of the run. With both paths at full column diameter also helps the stability of the vapor as well.

Genius.
ss

One thing I would add...add a vent tube from the sealed end of the LM condenser back to the CCVM tube to help balance the pressure of the vapor. The LM condenser is "dead-ended" and might not flow vapor properly without the vent.

[still_stirrin]

CCVM/LM with vent

Something like this, I'd imagine.
ss

[bellybuster]

KegJam... looking at your drawing I see the LM side never able to see vapour. Vapour will always take the path of least resistance, you have a reducer up to the LM side and the CCVM side is wide open, I can't imagine vapour ever going past that wide open port especially with some cooling there.
I could be totally off the mark here too....it happened once waaaaay back when I was a youngin

[Hound Dog]

I could be totally off the mark here too....it happened once waaaaay back when I was a youngin

I hear ya Belly, I thought I was wrong once myself but I was mistaken.

[Kegg_jam]

I'm liking hooklines drawing the more I study it, especially with the vent added by SS.

I'm honored to have you guys contribute.

[Kegg_jam]

Oh. For the record I had no illusions of the vapor splitting equally. I suppose the main goal was attaining better heads extraction which is usually painfully slow for me anyway.

[Danespirit]

As Bellybuster mentioned the vapoursplit could be an issue...
Anyway, as a even vapoursplit is not your goal, i still see your solution working...
Sure there will be more vapour on the CCVM side, but with the condensor running, it will just reflux back into the column.
Some time ago i had a idea of a low cost CCVM/LM head , with both solutions inline.
That way the vapour can only take one way up the column and the vapoursplit issue is void.
It also uses just one coil, so cheap and easy to build.
I have not yet had the time to build it, so unfortunatly i have no testrun to refer to.
With the coolingcoil active it will run LM and overflow to column, with the coil moved the VM would be active for takeoff.
Here it is: http://homedistiller.org/forum/viewtopi ... 17&t=54153

[Kegg_jam]

Dane, I forgot about seeing your idea. That's a good one.

[HookLine]

One thing I would add...add a vent tube from the sealed end of the LM condenser back to the CCVM tube to help balance the pressure of the vapor. The LM condenser is "dead-ended" and might not flow vapor properly without the vent.

Can't see the point of the vent.

I am not trying to balance the vapour split. I am trying to make the vapour go either one way or the other, but not both at the same time.

If the LM condenser is not running then all the vapour will go up the VM path (eventually, after the LM condenser mass has heated up and stopped passively condensing vapour). This is why the end of the LM condenser housing is sealed.

If the LM condenser is running and working properly then all the vapour going into that arm should be fully condensed before it hits the sealed end and there will be no back pressure issue. And if the bottom of the VM condenser is high enough above the LM condenser then no vapour should reach the VM condenser as it will be sucked into the LM arm and condensed before it can rise that high. The LM condenser is in effect bleeding off the pressure from below the VM condenser.

Think about atmospheric pressure bearing down on the rising vapour through the open top of the column. If that is higher than the pressure from below – in the space between the two condensers – then the vapour will stop rising up the VM path. In LM mode the vapour ideally should never reach the VM condenser. It is running purely as a safety backup if the LM condenser doesn't work properly.

I am very sure this design will work in principle. The big design question is, how much vertical clearance is required between the two condensers to give us that effect? Is it small enough to make this a practical design?