In line liebig design

[Alchemist75]

I'm trying to come up with a good inline Liebig design for my column but I need some suggestions.....
Water input needs to be at the top of course but if I put the outlet at the top as well will the water actually circulate fully through the jacket during operation or will it simply fill and then only circulate at the very top? I've tried angling the outlet line upwards to try to get water to "meet its own level" but it doesn't work that way in a pressurized system. Ideas? Knowledge?

[Alchemist75]

I'm currently using a coiled 1/8" copper tube around the vapor path at the very top of the dephlegmator with an array of through condensers below it. Below all that is a centering lip of and then down to the packing. It's not the most efficient design I know but it does work. I'm thinking a liebig would work better still than that coiled design but getting it to work well at a vertical angle may be a challenge if not impossible.

[The Baker]

I'm trying to come up with a good inline Liebig design for my column but I need some suggestions.....
Water input needs to be at the top of course but if I put the outlet at the top as well will the water actually circulate fully through the jacket during operation or will it simply fill and then only circulate at the very top? I've tried angling the outlet line upwards to try to get water to "meet its own level" but it doesn't work that way in a pressurized system. Ideas? Knowledge?

'Water input needs to be at the top of course...'
In English this can be taken more than one way, at first I thought you meant 'at the higher end of the barrel of the condenser'.
But I think you probably meant (at the lower end of the barrel of the condenser but) at the higher side of the barrel of the condenser.
(Of course this, 'higher side of the barrel', does not apply if the condenser is vertical, mine is slanted).

My little liebig condenser is fixed to the riser and the fellow who brazed (whatever) it for me put the inlet at the lower END and the outlet at the upper END but both at the upper side of the barrel.

Big problem. The hose twisted and would have cut off the water; so I had to rig a little frame for the hose to make a gentle curve so it would hang down.
If he had set it up so the hoses would HANG, no problem.
His idea was to avoid possible bubbles but that does not seem to be a problem.

Geoff

[Alchemist75]

Lol. Sorry, my verbage could probably have been a bit more clear. So the typical liebig would have an inlet port at the lower end and an outlet port at the upper end. This is fine but if it's at the top of the column we want the coldest water coming in at the top of the condenser and exiting the lower end. This doesn't work well with a vertical liebig, the condenser will not fill up using the normal configuration. I'm trying to design a liebig where the cold water enters from the upper end. The challenge with this is the place to put the outlet port. It could also be placed at the top of the condenser but I have a feeling that the water wouldn't actually circulate through the whole condenser. The jacket would fill up and then the cold water would only flow in and out at the top. Water seeks the path of least resistance naturally. I'm trying to think of a way to make it possible to pipe the water in at the top and ideally out at the bottom but unless there is something I fail to understand I'm not clear that there's a good solution to this problem. Does that make better sense?

[Alchemist75]

This is why I currently employ the spiral tube condenser idea. It's possible to have the water inlet at the top with this design. The coolant in my condenser "array" flows down through the coiled 1/8" tubing and then down to the through condensers.

[Kareltje]

I have a feeling I miss something important.
When I hold my Liebig vertical and insert water in the top inlet, it comes out at the bottom opening. No problem! Has something to do with Newton, if memory serves me well.
The condensate would be more of a problem, because it will flow back downward.
When I read your question I thought of something like this:

Vapour enters the central pipe from below, turns the corner and condenses in the second pipe, leaving this through a bottom outlet. Water enters the outer pipe from above and flows down, leaving at the bottom.

I have seen several of this kind of designs, but don't know where.

But maybe I do not understand your real question??

[Skipper1953]

How about placing a bleeder valve at the highest point of the condenser jacket? By restricting (temporarily) the flow of water from the outlet of the jacket and opening the bleeder valve, you could force the jacket to fill with water and push out the unwanted air.

[Alchemist75]

@kareltje:
That's an interesting design, I think it still has the same problem a regular liebig would have in that the coldest part is still the bottom of the condenser.
@skipper:
I thought about that, might just work. I'll try that with one of my glass condensers to see if it works.

I rebuilt my whole column and product condenser, just finished it up today. I did a quick trial run with water to check performance and it hums. The outer copper spiral tube condenser is underrated. I used it also on my initial prototype and it's surprisingly efficient and allows for proper flow direction. A liebig would be even more efficient but until I can figure out a way to make it coldest at the top I probably won't use one. Now all this is a result of comments made by Der Wo, he has stated multiple times that having coolant coming from the top and moving down is the best in terms of performance. It maintains the temperature gradient more evenly I suppose. Some cm style columns use a liebig condenser and I wonder if the performance is actually affected by the direction of water flow or if this is strictly theoretical. I don't know enough about engineering to be able to say one way or another, I only know what I read and the folks doing the writing are probably smarter than I......

[acfixer69]

That's an interesting design, I think it still has the same problem a regular liebig would have in that the coldest part is still the bottom of the condenser.


That is what you would want. Counter flow it has less thermo shock "vapor collapse" "huffing" and aids in a less finicky water adjustment.

[Alchemist75]

@acfixer:
OK, now I'm all afusededed. So you're saying that you would WANT the cold water entering from the bottom of a liebig style dephlegmator as it would reduce shock cooling? I get that's how you want your water flow on the product condenser but I would expect precisely the opposite on a dephlegmator. You want the bottom of the dephleg to be hot and the top cold. Right? Or no?

[acfixer69]

What I am saying is you want counterflow for each condenser, so both will be feed from perspective ends.

[Yummyrum]

Alchemist , your topic title may have confused a few people . Makes one jump to the conclusion that you are talking about a liebig as a product condenser when really you were meaning as a reflux condenser.

This may be why you are getting advise about running cold into the bottom .
Having said that , the majority of flute owners run cold into the bottom of the deflagmator and it still works . The reason its done that way despite being contray to the counterflow theory is to prevent airlocks and other hydrolic issues that would occur if you feed it from the top.

Salt bush bill however quite happily runs his deflagmator in a counterflow manner but he added a air purge valve for when he inially primes it .

A shot gun condenser is nothing more than a series of liebigs in parallel that share the same outer water jacket .

[Alchemist75]

I guess that settles the issue then. It doesn't really affect things in a noticeable way, good to know, I'll work with what I have now but when I finally upgrade I'll consider the liebig depending on what I end up building. It would certainly be cleaner and easier than the coiled tube concept. Thank you.

[shadylane]

I guess that settles the issue then. It doesn't really affect things in a noticeable way, good to know, I'll work with what I have now but when I finally upgrade I'll consider the liebig depending on what I end up building. It would certainly be cleaner and easier than the coiled tube concept. Thank you.

Based on my limited experiments, I'll have to disagree
A coiled reflux condenser is better than a shotgun

[The Baker]

Dunno about vertical Liebigs, all mine are/ will be slanted.

And soon I will probably be using my big coiled condenser in a water bath, the old traditional one. The Liebig runs on the house water supply and wastes too much water (which is not cheap).

Geoff

[Yummyrum]

Dunno about vertical Liebigs, all mine are/ will be slanted.

And soon I will probably be using my big coiled condenser in a water bath, the old traditional one. The Liebig runs on the house water supply and wastes too much water (which is not cheap).

Geoff

Geoff viewtopic.php?f=87&t=71307#p7531154

[The Baker]

Dunno about vertical Liebigs, all mine are/ will be slanted.

And soon I will probably be using my big coiled condenser in a water bath, the old traditional one. The Liebig runs on the house water supply and wastes too much water (which is not cheap).

Geoff

Geoff viewtopic.php?f=87&t=71307#p7531154

All these are product condensers on pot stills.

Geoff

[steelmb]

Dunno about vertical Liebigs, all mine are/ will be slanted.

And soon I will probably be using my big coiled condenser in a water bath, the old traditional one. The Liebig runs on the house water supply and wastes too much water (which is not cheap).

Geoff

+1
I have cheap cold well water and I will not use a liebig. A worm is so much more efficient and less problematic.