Copper chemical reactions?

BenStiller

As far as I know, both water and ethanol conduct electricity by the same mechanism and this mechanism requires the presence of electrolytes (of which ions is the most comon form). I have looked relatively quicly and have found a few sources that list the conductivity of pure ethanol as lower than that of pure water. Tables will list ethanol as "conductive" as it has the capacity to become so or is so unless purified, unlike other liquids, (like hydrocarbons for example).

I still do not see how mist or vapor can conduct electricity unless some kind or arc is formed.

Prairiepiss

Let's fill a bathtub with distilled water. And throw a hair dryer in it. And see who is willing to jump in.

And vapors don't have to conduct. When the walls of the still are coated with liquid.

Just saying.

And not having a proper ground. Doesn't mean you would get shocked. It means you are more likely to get shocked. You do have to make contact with two separate conductors. To get shocked.

jbierling

Did two more beer runs... both resulted with silver on all six of the plates. I suspended a bubble cap and some copper mesh in the pot with some string hanging from the 2" overhead access ports. Both did not have any evidence of silver.

Duck0fDeath

We fill transistors with pure ethanol as a cooling agent and it does not conduct electricity at all. We have thousands of volts in these circuits.

nvnovrts

Fusel oil?

Law_Of_Ohms

Looks like your going to need someone with a lab, maybe a local university? I'm sure you can bribe some students with some free hooch. They should have access to the relevant hardware.

grim

Do the bubble plate gaskets completely isolate the copper plates touching from the bubble tees? Or do the plates sit metal-to-metal? I'm thinking they've got to be metal to metal, based on the results of the string test. Asking because I've seen sieve plate gaskets that do isolate the plate from the column (plate sits in a U-groove) - can't for the life of me remember where I saw those though (similar to the crystal dragon gaskets, only in a standard gasket size - I think it was someone out in Europe who built their own).

This really now sounds like an issue with the heating elements and stray voltage causing some kind of galvanic reaction. The stray voltage does not need to be high enough for you to get zapped, a volt or two is sometimes enough to cause a plating reaction to occur.

Drop the same exact fitting onto a bubble plate on the next run, as long as it's in physical contact with the copper, I bet it gets coated.

Or, do the opposite. Take some teflon tape and wrap it around the edge of the bubble plate, fold it over both sides so that there is absolutely no copper/stainless contact. It might be a bit bumpy, but if you keep the teflon tape tight and give it a few loops around, it should be good enough to keep it isolated and not cause a leak. Pick a plate in the middle, I bet it stays clean. If I'm wrong, let me know where to mail the beer.

On another note, I did not have a similar issue, I only ran a very small volume though (only had 40lbs of spare rye floating around). I tried packing a column with copper mesh and running in 100% reflux for a good long while to ensure good contact. I'd say the mesh did appear to get darker quicker than I'm used to, and I swear I could see some silver glints/sheen/oil floating on the top of the water after rinsing them in a pot, but nothing quite like what you saw.

jbierling

@grim said: Do the bubble plate gaskets completely isolate the copper plates touching from the bubble tees?

No.

Or do the plates sit metal-to-metal?

Pretty much metal to metal. There really isn't much room at all for the plates if they're not perfectly placed inside the gasket. The bubble tees won't sit right and the clamp gets to be almost impossible to put on.

Drop the same exact fitting onto a bubble plate on the next run, as long as it's in physical contact with the copper, I bet it gets coated.

I think I will put a couple caps on top of a plate next time but isolate one from any metal contact with the plate.

Or, do the opposite. Take some teflon tape and wrap it around the edge of the bubble plate, fold it over both sides so that there is absolutely no copper/stainless contact.

That's a great idea.

On another note, I did not have a similar issue, I only ran a very small volume though (only had 40lbs of spare rye floating around). I tried packing a column with copper mesh and running in 100% reflux for a good long while to ensure good contact. I'd say the mesh did appear to get darker quicker than I'm used to, and I swear I could see some silver glints/sheen/oil floating on the top of the water after rinsing them in a pot, but nothing quite like what you saw.

You did or did not have a similar issue? Sounds like you did?

Philter

@jbierling Ive asked John Palmer, metallurgical engineer, and the author of "How to Brew" what his thoughts were on these silver deposits.

He is away on vacation at the moment and will reply next week.

I've had the same issue, but nowhere near as much deposit as yourself.

CothermanDistilling

Yeah, Palmer will likely know...

brantoken

just catching up here... very interesting thread.

There is a process called electro polishing , it is basically plating run backwards. I used to work in the medical industry and we used it to polish preformed wire parts.

1) it will polish to almost a mirror sheen on stainless wire.

2) so for plating we would need , Acid, electrtic charge .

3) could it be that the rye mash is very acidic? I guess the next question is can vapor or distillate be acidic. I know i have had some very acidic washes from rye flour, had one that stalled got down in the 3"s.

Not a clue how the electric potential could be different in different section of the still. Are sections of the still isolate electrically? or all one continuous piece?

I still can't imagine that that metal is going out the vapor path. So could the liquid runing down a wall be the electolite?

if this was happening the donor metal could appear very shiny, How are the inside of your tubes looking these days? Are there any very shiny metal parts, more so that when installed.

it is Just a thought......

I like the idea of getting a ground wire on the whole rig..... to make sure everything is grounded. Just went electric myself. Got some electrical engineer friend types, i got a safety review and a ground wire was a must. Not a bad idea anyway.

Duck0fDeath

Could just be build up from mineral oil

brantoken

check this out....

Galvanic Corrosion

There is definitely some galvanic potential here.....

jbierling

@Philter, any word from Palmer?

I wrapped half the plates with Teflon tape today. Rye will be coming up again in the next couple days.

Philter

@jbierling said: Philter, any word from Palmer?

No doubt after a vacation his email box would be full. Like mine at work, you take a week or two off and there's 500 emails to wade through :-O

I'll send him a reminder.

Philter

Here is Mr Palmer's reply:

I think it is zinc too. Dont know where it is coming from, but it would make the most sense galvanically, where a high activity metal (such as zinc, aluminum, tin, or lithium) would plate onto a more cathodic or low activity metal like copper, titanium, nickel, stainless, etc. Galvanically, it would be difficult for stainless or nickel to plate onto the copper, they are too electrically similar.

So, there has got to be a source of a light metal somewhere in the system where the pH of the mash is low enough to dissolve the metal and plate it onto the copper. The fact that it floats on the liquid is odd though.... Normally that would not happen in industrial plating, but then again, this is a unusual situation so who knows what's normal in this case.

The source of the metal could be an herbicide or something that is sprayed on the barley (pure speculation) but it is more likely coming from a galvanized piece of metal in his system. Or could be coming from brass or bronze components. He should check the pH of the different mashes. I bet the beer is much lower than the sugars and rye.

Also, he should check his electrical ground on the still. If there is a short or something then the still could be acting like a plating bath when the electrolyte concentration is high enough (ie beer) and then it could be a component of the stainless plating onto the copper. Have him look all over for signs of corrosion/pitting/etched appearance. Hope this helps, John

I thanked him for taking the time to help with this issue

jbierling

Thanks @Philter. Pretty much the same bases that have been covered before. I don't think the mashes are that much more acidic than the sour mashes... the sour mashes get to a pretty low pH sometimes. Something in the grain -- a long shot but possible I suppose -- its just standard Country Malt Products stuff though.

I've not found any pitting or corrosion other than the well known problem areas of the element bases. But these same elements are in wide use.

Rye is on the list for tomorrow. We'll see what happens to the teflon wrapped plates.

punkin

So far none of the people who have supposed it is a metal have explained how this metal is acting as a liquid at room temperature. Maybe it's Gallium, that has a melting point of 30C odd. As said above every type of plating i've ever seen has been fairly solid on the metal, haven't heard of anyone zinc plating water before.

http://www.lenntech.com/periodic/elements/ga.htm

Law_Of_Ohms

Jezzus Punkin, Havn't you ever watched Terminator 2 ?

jbierling, this could be the start of Skynet.

grim

You don't need to approach the melting point of a metal for galvanic plating to take place.

CothermanDistilling

we have gas-fired folks, right? If there is someone who runs gas who knows someone who runs electric and sees the stuff in person and can say 'holy crap, I have never seen anything like that!', then we know where it is coming from, right? If a gas fired person has seen this, then we know it has to come from somewhere besides the electric element...

BenStiller

@punkin said: So far none of the people who have supposed it is a metal have explained how this metal is acting as a liquid at room temperature. Maybe it's Gallium, that has a melting point of 30C odd. As said above every type of plating i've ever seen has been fairly solid on the metal, haven't heard of anyone zinc plating water before.

http://www.lenntech.com/periodic/elements/ga.htm

The metal would not become a liquid as part of the proposed electroplating process. The zinc present on some component would be dissolved as zinc ions in the wash. The zinc ions would then form a compound that would be volatile and would be carried in the vapor. The compound would then electroplate on the copper, reforming metallic zinc.

Volatile metal compounds do exist but I do not know of any obvious ones for zinc. I am still unconvinced that this is what is happening but this would be a possible mechanism for it to happen.

mort

That would be me, but it's kind of another source of frustration as it happened in my early days, before I had access to the forums and all. I'm talking 15 years ago. I mentioned it to jbierling on AD but could not really add much. My best recollection is it rinsed off of copper that had been in the vapor path. My "opinion" is it came from the wash. I was using materials I haven't used in years, turbo yeast, clarifier, feed molasses of some sort maybe. But all gas-fired for sure.

grim

Impatiently waiting for the next results...

jbierling

Just got to the rye today. Same silver on all the plates -- including the teflon taped ones.

Grip

Just taken my 11 copper bubble plate crystal column apart fro cleaning and there on a couple of the plates was a 'zinc-like' plating. I used a turbo yeast in the wash, could zinc be a turbo nutrient?

Law_Of_Ohms

What is your rye recipe. I will have a go at a scaled down mash to see if I can replicate

jbierling

@Law_Of_Ohms:

@jbierling said: Here's the protocol:

Add 70 gallons of water at 158F. Add 6.0lb rice hulls then 150lb of malted rye. Temp drops to 146F. Add 60g enzyme. Rest 90 min. Temp drops to 130F. Sparge. Add 15 gallons of sparging water. Add enzyme at 122F->116F. Pitch US-05.

Nothing else. No other enzymes.

Law_Of_Ohms

What enzymes? , What rice hulls? (stock feed grade?)

jbierling

@Law_Of_Ohms said: What enzymes? , What rice hulls? (stock feed grade?)

Saczymeextral & saczyme. Country malt group's hulls.