Home Distiller

I can lay my hands on some of this. 15mm OD pipe with varying diameters of fins.

I think it will work, any opinions.

http://www.spiralfinnedtube.com/photo/p ... hanger.jpg

https://homedistiller.org/forum/viewtop ... 6#p7295199

Others have done air cooling. Would likely need forced air movement unless made really long.

As already mentioned, I think it needs forced ventilation to have acceptable performance, or it should be very, very long. M is just an opinion, no direct experience.

I'd be concerned with how easily the fins could be damaged or bent over. It doesn't look very robust. I wouldn't want something like that unless I had a place where my still could be set up very long term.

It looks pricey. I would enclose it in a water jacket (Liebig), but the fins are so close together I doubt you would get much cooling turbulence. I use finned tubes in my liebig and reflux condenser(coldfinger) but the spacing is much wider and alternately notched for cross-flow. If you use it as a product condensor, you would as others have pointed out, have a fan or blower pointed at it. These things look like a base board heater strips.

This is not like finned tube baseboard.
This looks just like copper-fin that is used in heat exchangers for copper finned tube boilers.
The copper finned tube used in heat exchangers is a very stout product that we aggressively clean with wire brushes without worry of bending the fins.
It also has a better heat transfer rate being the fins are copper and all made from one piece (fin & tube)
I would think this could make a great condenser either with fans or better yet as a tube and shell as long as you put diverter plates every few inches.

I experimented with my old half inch x 9 foot worm connected in before my Liebig condenser. I had a fan blowing air over the worm and result was lower water temp on the output of the Liebig, this meant I could do a whole stripping run without swapping out the cooling water instead of half way through. This sort of tube would be ideal if the ID is big enough to cope with the vapour volume.

So I wanted the finned tube as the distillate tube in a Liebig.

Was not thinking of air cooling although it is an attractive option. One could drape the finned tubes in a suitable medium, wet it and blow air over it evaporatively cooling it. Starts getting complicated.

A rifled inner tube would work well.
Promotes movement on both inner and outer sides of its tube wall.

Andrew_90 wrote: ↑Mon Oct 05, 2020 3:41 am So I wanted the finned tube as the distillate tube in a Liebig.

Are you trying to achieve something particular? Simple liebigs work well for the jobs they are hired for. Simple mods like the very cool rifling, or spiral wire turbulaors are easy optimizations. The linked pipe is a cool looking product but I can't quite picture a need for it. Of course innovation often involves a lot of trying something just to see, nothing wrong with that.

So I can get the finned pipe for free in varying diameters.

More fins = better utilisation of the cooling water = more efficient cooling is my though process.

Proven air cooling solution:
Use regular liebig and a water barrel. Just install car radiator (with a fan, of course) between a liebig and a barrel. Plus you need a pump to recirculate. We build such a setup at my friend's garage and it work pretty well. Summer time fan blows all air out of a garage, but we also installed deflator to divert part of air back to garage for winter time.

Andrew_90 wrote: ↑Mon Oct 05, 2020 12:34 pm More fins = better utilisation of the cooling water = more efficient cooling is my though process.

Not necessarily, I could see those fins playing hell on flow through the shell. Maybe even to the point it's no better than a smooth pipe. If you just put that pipe in a shell like a typical liebig, what directs the water to flow through all the fins? I'd guess exactly how tall the fins are would make a big difference and if they fill the shell ID or not. And you really need to define efficiency and use case, most liebigs are capable of efficiently condensing and subcooling the distillate they are pitted against with length being the only variable. Do you need a shorter liebig? More condensing power for the same length? More subcooling? If not, then more efficient heat transfer doesn't really get you anything (other than a kick ass condenser). These pipes are designed for air, in flowing water heat transfer is already about 100x more efficient which is why you don't see something similar often.

If you have one with a fin OD = to a convenient shell ID then I guess you could shave down half the fins every (shell ID)", alternating sides so you end up crossflowing coolant zig zagging across the pipe and fins without restricting flow too much. Then you still get maximum coolant flow and surface area. It'd be a ridiculously awesome liebig, only relevant when measuring it against itself, but still awesome.

Or just put it in an oversized shell and see what happens.

Free is pretty powerful motivation to play with it. Your link states lots of sizing options, so exactly which are available would determine exactly what I'd personally do with it. Well, that and what I was building a condenser for.

Kinda like this?
https://homedistiller.org/forum/viewtop ... 6#p7584553

Pretty much

If that rifling is inside the pipe as well , you might like to think about weather it could cause pooling and smearing before proceeding with the idea.

Andrew_90
If I could come across some finned copper pipe like that, I would construct a "cold finger" condenser where the vapor input/liquid output is in the shell of the condenser and the cooling water runs though the finned pipe in the center. You would have to run this contraption at an angle, say 30 degrees or so, to keep your product from pooling on the fins.

Very interesting.

Saltbush Bill wrote: ↑Mon Oct 05, 2020 8:46 pm If that rifling is inside the pipe as well , you might like to think about weather it could cause pooling and smearing before proceeding with the idea.

Has not been a problem Bill.

So in an ideal world, assuming water rather than air as the cooling medium, and not taking into consideration any manufacturing practicalities;

If one could get a spiral between the distillate tube and the outer tube of a Liebig, that forced the water to do say 2 to 5, 360 degree turns around the the inner distillate pipe then would it be safe to assume that one meets and exceeds the requirements for the flow of water and elimination of dead spots?

Send me three or four feet of the finned tubing and I'll let you know.

Those are spiral fins on that copper tube, If I was going to make a liebig with it I would put it inside the tightest fitting pipe possible and run the water in from the end cap and out the other end cap. When I wire-wind my vapor tube (1/4") I space the spiral about half inch on center or less and solder every rung to the vapor tube so the wire acts as a heatsink as well as a turbulator. I don't bother soldering all the way around, just one spot all the way down the length as it sits in front of me.