Copper mesh in the vapor path

[PalCabral]

Good morning (early here).

EDIT: let me rephrase my convoluted question, guys - I blame not having had my morning coffee yet, basically I wasn't human when I wrote the post.

How do you "put copper" in the vapor path if all your still components are SS? Do you put copper mesh in the column tubes or do you use some other material? Are you also "putting copper" in the lyne arm and at the spout where the product comes out of the PC?

Background "talk" from a coffee starved brain below:
As I was packing my column tubes with copper mesh for today's run with the reflux still I started thinking about the other reason to why have copper in the still. Often repeated on this forum, distillers are reminded to have copper somewhere in the vapor path because of the positive reaction that copper have on sulfur impurities in the alcohol vapors, cleaning some of it up.

In my case, one of my column tubes is made of copper, all other components of the still are made of SS (304). This equates to half of the total height of my column is copper when set up for reflux distilling, more so when in pot still mode, as it is the only riser I use. I figure this set up is sufficient.

However, with all my column tubes packed with copper mesh for the run today, I realized have a lot of extra copper mesh lying around. I was thinking if I should, for the sake of the copper's cleaning abilities, also put some loose mesh ends elsewhere in the vapor's path, for example in the elbow/lyne arm where vapors are taken to the product condenser. Would it make any difference to put some mesh there or would it rather introduce unwanted reflux at the critical point where vapors are supposed to leave the still?

[NZChris]

What are you making?

Smell the charge. If it is low in sulfides the extra copper might make no difference.

What is the charge? If the charge is fresh wash it is more likely to contain sulfides than low wines.

[PalCabral]

What are you making?

Smell the charge. If it is low in sulfides the extra copper might make no difference.

What is the charge? If the charge is fresh wash it is more likely to contain sulfides than low wines.

I wasn't making much sense, Chris, sorry. I had to edit the thread, did it while you answered.

It's more a generic question. How do I "put copper" in the vapor path if my still is SS and how far should I go?

[MooseMan]

If you have the column packed with copper mesh that's more than sufficient I'd say.

And on a pot run, if your riser is copper then you are good. I've actually just made a copper riser for my pot, as I have been using my ccvm head flipped over, all SS.
I've never been concerned about sufficient vapour/copper contact since my condenser is copper.

[higgins]

Check out this paper on placement of copper in stainless steel stills:
The Impact of Copper ...

Their conclusion is that the best placement of copper was the condenser of the wash still (stripping) and the kettle of a spirit still.

My 2" x 20" shotgun condenser is copper, so that works for stripping, and I have about a dozen 1/2" copper elbows that I put in the kettle during spirit runs. I just rinse them off & let them air dry, then store in a mason jar until next time.

[Dougmatt]

I have some copper mesh in the vapor path right before my condenser (packed slobber box) and I throw a wad in the boiler for every run. That way I’m covered for both in my ss rig.

[OtisT]

My still is mostly stainless but I do have a copper product condenser. I keep some copper bits in my boiler all the time and I also put a small section of wire mesh in my riser. (Small section is a 1’ long section from a 5” wide roll of mesh. I attach it inside the riser by pinching a single copper thread in a tri clamp joint as I assemble things, so it dangles freely).

Not sure if it’s overkill, but I have not had any issues with the smell of sulfur.

After each run I clean the mesh by soaking it in the hot backset/dunder.

[Tammuz]

I bought some copper coming of a lathe. I thought I was getting long spirals coming off the lathe. I only got 20% that was like that. With the fine stuff I ended up buying a 4" tea bob that I hang a few inches below my boiler. My friend used in running some rum. It really grunged up the copper,had to soak it in some citric acid to clean. I believe it worked better then copper in the column on pot run. Bought off of eBay.

[Homebrewer11777]

I'm not sure about the interpretations of that Harrison paper encouraging adding copper into a boiler. Harrison's still may have more copper in the vapor path from the cone shaped lid of his boiler (look at figure 1) than it has had in the entire lyne arm section depending on how full the boiler was...and the copper in the lid of the boiler probably encounters much more vapor than the downstream sections as the still refluxes.

Copper in the vapor path clearly works from is S2 and S5 results, having the same copper in the same place in both the wash still and the spirit still (or more likely using the same still with the same copper for both wash and spirit) would presumably work better than only one or the other.

Practical experience that frequently shows up here and other forums says some copper in the vapor path is good enough. I've been following that advice and happy with the results. I found I like a bunch of short copper tubes cut from some scrap pipe in my 3" riser better than copper mesh. They have developed a nice patina. I rinse them from time to time but don't wash them with acid or PBW unless I had a puke.

[PalCabral]

Check out this paper on placement of copper in stainless steel stills:
The Impact of Copper ...

Their conclusion is that the best placement of copper was the condenser of the wash still (stripping) and the kettle of a spirit still.

My 2" x 20" shotgun condenser is copper, so that works for stripping, and I have about a dozen 1/2" copper elbows that I put in the kettle during spirit runs. I just rinse them off & let them air dry, then store in a mason jar until next time.

Interesting paper. I've heard (on this forum) so many different version of where the copper would do best use: some say boiler, some say in the vapor path before condenser, and some say condenser. The fact that the studies showed different results for the stripping run and spirit run kinda explains the different views.

I must admit that tossing copper into the boiler making difference was surprising for me. That sounds like superstition to me but there you go - for a stripping run it would make sense. At the same time, I dont have a copper product condenser and looking at the copper shotgun condensers from China they look like the tubes are made of steel, only the jacket is made from copper, which would defeat the purpose. Building my own Liebig in copper would probably be the best way to have the optimum spirit run configuration. Not sure it's a task for 2025 though, I just got the shotgun condenser and it cost a bundle.

I've seen some pics where ppl put mesh up the spirit spout off the condenser. Again, sounds like someone's wish rather than a fact - but hey, I was wrong about copper in the boiler. Who am I to knock it down? Thanks for the link!

[Homebrewer11777]

Again...that paper says nothing definitive about putting copper in the liquid in the boiler. The entire boiler is made of copper including what is likely a large headspace.

[NZChris]

If research contradicts opinions, I use the research results.

If I don't have copper somewhere where it is advantageous, I do something about it.

[Salt Must Flow]

My stills are all stainless. I put 3-4 rolls of copper mesh at the base of my riser when I'm doing stripping runs. When I'm doing a spirit run with my reflux column, I use 2-3 rolls of copper mesh at the base of the column and fill the rest of the column with packing. For the copper mesh to stay put, there are many different ways to create a retainer. The easiest way is to just solder some copper wire across the base of the pipe.

[Fletching]

On adding copper to the elbow/lyne arm, I did this once on my CCVM reflux column between my RC and PC. I was thinking an extra roll of copper wouldn’t hurt. I was wrong. I experienced a great amount of surging, struggled to find the “sweet spot” on my RC, and the proof suffered.

I shut down, removed that roll of copper, started back up, and it behaved just as it usually does.

I haven’t stuffed any copper between the two condensers since.

[Homebrewer11777]

I got a PTFE TC gasket with SS screen from Amazon to hold my copper tubes.

[PalCabral]

On adding copper to the elbow/lyne arm, I did this once on my CCVM reflux column between my RC and PC. I was thinking an extra roll of copper wouldn’t hurt. I was wrong. I experienced a great amount of surging, struggled to find the “sweet spot” on my RC, and the proof suffered.

I shut down, removed that roll of copper, started back up, and it behaved just as it usually does.

I haven’t stuffed any copper between the two condensers since.

Yeah, this is what I was worried about.

[Yummyrum]

One thing that hasn’t been mentioned here is Ethyl Carbomate .
There are quite a few topics on here about it .
This one for example .
viewtopic.php?p=7275807#p7275807

As we know copper removes sulfer , but it also creates a carcinogen called ethyl carbomate .
So long as the copper is in the riser , ethyl carbomate will remain in the boiler and riser .
Hiwever , if there is no copper in the boiler and riser , but only in the condenser , then the ethyl carbomate will be formed and end up in the collection vessel .