Alcolengine "mod" advice

[Warthaug]

I have a kegland alcoengine pot still which I have been using for a while. I've mostly use it as a pot still (and am quite happy with it in that role). But I also use it as the condenser for a simple column still. I have a column that is literally just a 500 mm (~20") 2" triclamp extension tube that I clamp onto the still, and then clamp the alcoengine on top to act as a condenser. This gives me an ~800 mm (32") long column that works OK (essentially a 15:1 height:diameter ratio, which I understand to be the bare minimum for an effective column, with 20:1 considered to be better). If I pack the column with copper mesh I can get upto ~90% ABV, but I cannot get higher and would like to get closer to azeotropic.

While extending the column by adding another extension tube is one option, I was thinking that adding a dephlegmator would be more controllable. I was thinking I could drill holes at the top of the extension tube to attach a copper coil, with the coil made in one of two ways:

1. Position the copper coil at the top of the column. This would be the easiest to make, but the dephleg would be 300 mm (~12") below where the distillate flows into the condenser.
2. Make the copper coil with "arms" that extend it above the top of the extension tube, so when the still is assembled, the coil is at the top of the alcoengine - e.g. at the same height as where the distillate flows into the condenser. Probably better positioning of the depheg, but harder to make, and I would have ~12" of exposed copper carrying water too/from the coil.

I suspect the latter option is the better one, but its still "weird" compared to most dephleg's, which seem to always be placed above the arm running to the condenser.

Would this work? Is this a waste of my time? Is there a better way to make this work that doesn't involve making/buying a whole new setup?

Thanks

B

[Sporacle]

I have a column that is literally just a 500 mm (~20") 2" triclamp extension tube that I clamp onto the still, and then clamp the alcoengine on top to act as a condenser. This gives me an ~800 mm (32") long column that works OK (essentially a 15:1 height:diameter ratio, which I understand to be the bare minimum for an effective column, with 20:1

I'm confused, are you simply clamping your pot still head on top of your extension? If that is the case then you have just extended the riser and have not created a reflux still. In order for that to occur you need a reflux condensor and a product condensor in simple terms.
As you are using a modular system have a search for CCVM, it sounds like you are trying to build something similar, Kimbodious has a great modular setup with heaps of info

[Warthaug]

I have a column that is literally just a 500 mm (~20") 2" triclamp extension tube that I clamp onto the still, and then clamp the alcoengine on top to act as a condenser. This gives me an ~800 mm (32") long column that works OK (essentially a 15:1 height:diameter ratio, which I understand to be the bare minimum for an effective column, with 20:1

I'm confused, are you simply clamping your pot still head on top of your extension? If that is the case then you have just extended the riser and have not created a reflux still. In order for that to occur you need a reflux condensor and a product condensor in simple terms.
As you are using a modular system have a search for CCVM, it sounds like you are trying to build something similar, Kimbodious has a great modular setup with heaps of info

You're not confused, that is exactly what I have done! E.G. its a passive column still, where what reflux there is, is that which that occurs spontaneously due to condensation within the column. I'm trying to find a way to add a reflux condensor to be able to actively drive reflux. I *think* that what I'm describing of building is a cooling management reflux still (I'm not 100% certain of the terminology). Definitely not a CCVM.

[Sporacle]

I understand what you have done, that's not a reflux still and it's not a column, it's a riser.
If you are looking to put a open coil as your reflux condensor then why not go modular and have the reflux condensor movable and do away with an expensive valve by building a CCVM

Edit I'm still a bit confused it sounded like a VM still hence my valve comment

[GrumbleStill]

Hi Warthaug,

As others have said, at the moment you have a pot still with a packed riser that gives you some passive reflux.

If you made or bought a short (200mm should do it for an alcoengine) shotgun condenser and put it between the top of the packed section and the alcoengine, you would have a Cooling Management (CM) reflux column.

[Warthaug]

Hi Warthaug,

As others have said, at the moment you have a pot still with a packed riser that gives you some passive reflux.

If you made or bought a short (200mm should do it for an alcoengine) shotgun condenser and put it between the top of the packed section and the alcoengine, you would have a Cooling Management (CM) reflux column.

Thanks - that seems like a good route forward. I don't distill enough to justify building (or buying) a whole new still, but I do have some random 2" extension tubes that I should be able to convert into a shotgun - probably easier than trying to make a copper coil that would fit inside a 2" pipe!