Abrasive Mill

[stoneware]

For those interested in real science.

Experimental abrasion of detrital gold, read from page 203/212,

https://pubs.usgs.gov/journal/1975/vol3issue2/report.pdf

 

[MicheleM]

Unrefined palladium with a bit of gold, this will be going to EDI in Ontario.

It appears to me the palladium content on e-waste exceeds the gold content.

View attachment 53326

View attachment 53325
I would wait your refined product , because based on numbers you gave this is a unrealistic claim

 

[stoneware]

Cheap shot MicheleM

Palladium content in projection televisions, Hammond organs and PSU's where no gold is present, will change the percentage of gold in your concentrates.

 

[kurtak]

Personally I don't care if your a none believer

stoneware --- it's not that I am a "non believer" in the concept of the ability to remove metal by abrasion

In fact quite the opposite - I fully understand how metal removal by abrasion works

It works on the physical force of friction when two sold objects are rubbed together - that is the basic concept

How effective the abrasion is depends on the physical characteristics of the object being rubbed together such as hardness &/or texture of the objects

Example; - if I take two polished copper bars & rub them together I won't remove very much metal from the surface of the two copper bars & that is because both bars are the same hardness & being polished have no real texture - I won't get a whole lot of copper powder abraded away from the copper bars

On the other hand - if I take a copper bar & rub it with a piece of 2000 alumina grit sandpaper I will get a nice pile of copper powder & that is because the alumina grit (alumina is a VERY hard ceramic) provides both hardness & texture to abrade copper from the softer copper bar ---at 2000 grit the alumina sandpaper will abrade copper in such a way that it will also polish the copper

That is why I use my vibrating tumbler to polish my brass for reloading ammo as well as polishing the sterling jewelry I make using crushed walnut shells as the "abrasive" polishing media - the walnut shell is harder then the brass/silver & as well the walnut shell has texture so it abrades brass/silver from the surface of the metal which polishes the metal & there will be metal powder in the walnut shell polishing media

I know that you understand this & that I don't need to explain it to you --- I post all of the above to show that I also fully understand the concept of abrasion

So in no way am I saying that your abrasive mill won't work & in fact I posted that yesterday when I said ----

To clarify - at the same time - I am NOT saying that your system won't recover value - it will

Rather - my issue here - is the very unrealistic expectation of PM recovery you are posting about here with your abrasive mill --- & that is especially true when I consider the feed stock you are running in your mill

Example; - you posted ---------

Unrefined palladium with a bit of gold, this will be going to EDI in Ontario.

It appears to me the palladium content on e-waste exceeds the gold content.

along with that you posted a pic of your scale read out of this powder (also pictured) to be 93.4 grams of unrefined palladium --- recovered from (about) 50 pounds of CBs run through your system

93.4 grams equals 3 ozt of Pd recovered from 50 pounds of CBs

that is not only unrealistic - but in fact outragedly unrealistic

it takes one full ton (2000 pounds) of CBs to get about (plus/minus) 1 ozt Pd

Yet you claim to be recovering 3 times that much Pd from only 50 pounds of CBs

So your claim is not just unrealistic - but unrealistic to the point of outrageous

And I am sorry - but the same holds true for the recovery expectations for gold & silver

That is because your feed stock (shedded CBs) is very low grade to start with (you can not recover 10 grams of gold from something that only contains 1 gram of gold to start with) & your system is not 100% efficient (in fact far from it) meaning you will suffer at least some loss at every step in the process

Bottom line - if the feed stock is low grade to start with the cost of processing is likely going to exceed the value of recovery --- so your feed stock needs to be high enough grade that the recovered value exceeds the cost to process

Your feed stock is not high enough grade to exceed processing cost

How do I know that --- because I spent 10 years making a living (making a profit) handling CBs by the ton - like 2 - 4 ton per month every month

I made my money by

Selling boards by the ton --- I sold all the low to mid grade stuff because trying to process it cost more then I could recover from it --- you CAN NOT make money processing 50 to 100 pound of this stuff at a time --- to make money processing this stuff you NEED to process it by the ton(s)

Sending boards by the ton to board smelters --- I sent my mid to mid/high grade stuff to a smelter because sending this stuff to the smelter paid a bit better then selling it to board buyers --- & again with this stuff - you CAN NOT make money processing 50 to 100 pound of this stuff at a time --- to make money processing this stuff you NEED to process it in batches by the ton(s)

And then I actually processed (only the very highest grade stuff) in large leaching or smelting batches (30 to 60 pound batches)

I think I know what I am taking about when I say - abrading LOW grade feed stock will cost more then you can recover

On the other hand - if you abraded only HIGH grade stuff - like gold plated fingers &/or fully plated pins you would make money

You will understand this when you finally actually recover the small amount of values from your acidic leach solutions --- it will not be even close to what you expect - you will be lucy to make what one day of work at a regular job pays you

I speak from years of experience --- making money --- handling CBs

You need to ether process VERY HIGH grade stuff --- or you have to process ton(s) of low grade stuff it in order to make money processing CBs

Kurt

 

[MicheleM]

Cheap shot MicheleM

Palladium content in projection televisions, Hammond organs and PSU's where no gold is present, will change the percentage of gold in your concentrates.

Clearly you don't know what you're talking about, even the colors are wrong. Anyway it's your time being wasted not mine.

 

[stoneware]

Kurt you were concerned about the cost of electricity.

 

[stoneware]

Clearly you don't know what you're talking about, even the colors are wrong. Anyway it's your time being wasted not mine.

You might be right, the mud could be copper.

 

[ChopperGreg]

In this thread the discussion was about removing silver plate the most economical way.
View attachment 53365

Link?

 

[stoneware]

Link?

Best Ball Mill Media for Plated Silver Removal​

Link

 

[goldshark]

Are you sure that you're not displaying a Pumpkin Pie? It would be funny if you pulled the wool over everyone's eyes at Thanksgiving, and nobody knew the difference.

 

[Yggdrasil]

Just my two cents.
I really do not like abrasion much, it is simple and fast but rarely complete.

Back in the days I was working with machining and welding Stainless Steel.

One always had to acid treat the weld seems to remove the oxide film.

Stainless aren’t very stainless unless it’s clean, even a paint spot can give rise to corrosion.

Anyway the acid paste was a nasty concoction containing amongst other HF, so we started glass bead blasting resulting in a fantastic finish… for a while.
But since abrading are not complete it started corroding after a while any way.

Upon investigation we found out that the blasting left behind quite a bit of invisible oxide layer in specks. It actually just pushed it around.

So for abrading you need to remove quite a bit more than you believe to be complete.

 

[kurtak]

Kurt you were concerned about the cost of electricity.

It's not that the cost of electricity in & of it's self is a big concern but the fact is that it is a cost none the less which is in addition to all the other cost

So if you run 50 pounds of very low grade material that is going to only recover a gram of gold then the cost of the electricity is only one cost factored into over all cost

This is why the grade of the material that you run in a system - any system - has to be high enough grade material that it will cover all cost plus some for profit on top of the investment cost

To put it somewhat in perspective lets use a hypothetical example

Lets start with 50 pounds of very low grade feed stock - so low grade that it only has 1 gram of gold in it & we will assume 100% recover (which NEVER happens) but lets assume that anyway We are talking about the kind of stuff you are running in your abrasive mill)

Lets call that 1 gram worth $55 at spot price (which again you are not going to get)

Now lets say running the shredder - the mill & hot plate only adds 5 dollars to your electric bill

The 1 gram gold is now worth $50

But then you also use another $10 in chem to get to that nice 999 refined gold button

The 1 gram is now worth $40

But - because you in fact will not get spot price & in fact will not get 100% recovery we can now figure in another $5 - $10 in loss

You now have a gold button (a bit shy of 1 full gram) worth $30 - $35 --- lets go with $35 for your actual gold value

Now lets look at the BIG cost - the cost of your time

1 day to shred 50 pound CBs - no time to run mill as you can do other things while the mill runs - 1 day to sift/wash the powders out of the shredded CBs - then - at least - 2 more days for all chem work - filtering - gold drop - wash chem out of gold drop - dry gold drop - melt gold into button

So - at least 4 days time (factored at 8 hour day) equals at least 32 hours of your time (probably more like 6 - 7 days)

Lets say your day job pays you $20/hour - that means the 32 hours time value is $640

Now I know you are going to say - "but Kurt this just a hobby so I don't care about my time" --- but lets be real here --- this hobby &/or any other hobby you do - you at least want to some kind of value return for the time spent at that hobby

So lets say your hobby time is worth $5 --- in order to have that feeling that the time you just spent on the hobby had some value --- 32 hours X $5/hr = $160 --- to recover $30 - $35 worth gold

AND - that is not the only time cost for that $30 - $35 of gold because you had to take time to run around in you car - put gas in your car (actual money spent on gas) to drag electronic stuff home - & the time to tear CBs out of the electronics to get your feed stock --- so even more time

And you have ended up with a pile junk in your back yard from tearing down electronics & a bucket full of TOXIC waste from chem work in your back yard --- to process 50 pounds of CBs

I know - now you are going to tell me --- "but Kurt I am cherry picking the higher value stuff like IC chip, fingers, fully plated pin, etc. to process also --- & I get that

BUT - processing all of that is also going to take MORE (MUCH MORE) of all the above - on the same 50 pounds of boards

50 pounds of modern day mother boards will give you right at 3 grams of gold (IF you recover 100%) which is worth (about) $165 --- the fact is - you will NEVER recover 100% with back yard refining - at best 2/3 so you are down to 2 grams worth $110

Ya but Kurt some of the boards are going to be higher grade

OK - lets double that to $220

Ya but Kurt what about the silver & palladium (to be honest you are not going to see much here maybe $100)

But - lets double it again to $440

Ya but Kurt I can sell the iron - aluminum & copper/brass to the scrap yard

OK - lets add another $100 --- for a total of $540 from processing 50 pounds of CBs

To get that $540 dollars in value it is going to cost you (about) one month in time - $10 - $15 in electric & (about) $100 in chem - with 2-3 buckets of TOXIC waste in your back yard

So --- $540 actual recovered metal value minus $100 actual cost = $440

So --- is a month of your time - the mess you create in your back yard - & the buckets of TOXIC waste you end up with in your back yard worth that $440 in metal you recover from processing 50 pounds of consumer grade CBs ????

Ya but Kurt that's just one 50 pound batch & I plan on doing more then just that one 50 pound batch

Really - OK - then you are starting to approach a fulltime job - if not a fulltime job --- would you work at a fulltime job for $440 a month

Ya but Kurt I am going to improve my system to get better results

OK - lets double it again plus a bit to $1000 a month --- would you work a fulltime job for $1000 a month

The bottom line is that you can not - will not make money processing low grade consumer CBs

Now ask me how you make money processing CBs

Kurt

 

[stoneware]

It's not that the cost of electricity in & of it's self is a big concern but the fact is that it is a cost none the less which is in addition to all the other cost

So if you run 50 pounds of very low grade material that is going to only recover a gram of gold then the cost of the electricity is only one cost factored into over all cost

This is why the grade of the material that you run in a system - any system - has to be high enough grade material that it will cover all cost plus some for profit on top of the investment cost

To put it somewhat in perspective lets use a hypothetical example

Lets start with 50 pounds of very low grade feed stock - so low grade that it only has 1 gram of gold in it & we will assume 100% recover (which NEVER happens) but lets assume that anyway We are talking about the kind of stuff you are running in your abrasive mill)

Lets call that 1 gram worth $55 at spot price (which again you are not going to get)

Now lets say running the shredder - the mill & hot plate only adds 5 dollars to your electric bill

The 1 gram gold is now worth $50

But then you also use another $10 in chem to get to that nice 999 refined gold button

The 1 gram is now worth $40

But - because you in fact will not get spot price & in fact will not get 100% recovery we can now figure in another $5 - $10 in loss

You now have a gold button (a bit shy of 1 full gram) worth $30 - $35 --- lets go with $35 for your actual gold value

Now lets look at the BIG cost - the cost of your time

1 day to shred 50 pound CBs - no time to run mill as you can do other things while the mill runs - 1 day to sift/wash the powders out of the shredded CBs - then - at least - 2 more days for all chem work - filtering - gold drop - wash chem out of gold drop - dry gold drop - melt gold into button

So - at least 4 days time (factored at 8 hour day) equals at least 32 hours of your time (probably more like 6 - 7 days)

Lets say your day job pays you $20/hour - that means the 32 hours time value is $640

Now I know you are going to say - "but Kurt this just a hobby so I don't care about my time" --- but lets be real here --- this hobby &/or any other hobby you do - you at least want to some kind of value return for the time spent at that hobby

So lets say your hobby time is worth $5 --- in order to have that feeling that the time you just spent on the hobby had some value --- 32 hours X $5/hr = $160 --- to recover $30 - $35 worth gold

AND - that is not the only time cost for that $30 - $35 of gold because you had to take time to run around in you car - put gas in your car (actual money spent on gas) to drag electronic stuff home - & the time to tear CBs out of the electronics to get your feed stock --- so even more time

And you have ended up with a pile junk in your back yard from tearing down electronics & a bucket full of TOXIC waste from chem work in your back yard --- to process 50 pounds of CBs

I know - now you are going to tell me --- "but Kurt I am cherry picking the higher value stuff like IC chip, fingers, fully plated pin, etc. to process also --- & I get that

BUT - processing all of that is also going to take MORE (MUCH MORE) of all the above - on the same 50 pounds of boards

50 pounds of modern day mother boards will give you right at 3 grams of gold (IF you recover 100%) which is worth (about) $165 --- the fact is - you will NEVER recover 100% with back yard refining - at best 2/3 so you are down to 2 grams worth $110

Ya but Kurt some of the boards are going to be higher grade

OK - lets double that to $220

Ya but Kurt what about the silver & palladium (to be honest you are not going to see much here maybe $100)

But - lets double it again to $440

Ya but Kurt I can sell the iron - aluminum & copper/brass to the scrap yard

OK - lets add another $100 --- for a total of $540 from processing 50 pounds of CBs

To get that $540 dollars in value it is going to cost you (about) one month in time - $10 - $15 in electric & (about) $100 in chem - with 2-3 buckets of TOXIC waste in your back yard

So --- $540 actual recovered metal value minus $100 actual cost = $440

So --- is a month of your time - the mess you create in your back yard - & the buckets of TOXIC waste you end up with in your back yard worth that $440 in metal you recover from processing 50 pounds of consumer grade CBs ????

Ya but Kurt that's just one 50 pound batch & I plan on doing more then just that one 50 pound batch

Really - OK - then you are starting to approach a fulltime job - if not a fulltime job --- would you work at a fulltime job for $440 a month

Ya but Kurt I am going to improve my system to get better results

OK - lets double it again plus a bit to $1000 a month --- would you work a fulltime job for $1000 a month

The bottom line is that you can not - will not make money processing low grade consumer CBs

Now ask me how you make money processing CBs

Kurt

I'm retired been on pension for the past 8 years, they pay me to stay at home so people like you have a day job.

What I do is far cheaper than sitting in the pub buying rounds for the freeloaders.

 

[goldshark]

As long as you know the real numbers, and can live with it, it's ok in my book. Everybody needs a putz. Sure beats standing on a street corner begging for change.

 

[stoneware]

Now that the mill is sitting idle, we're preparing 50 pounds of silver plate for abrading.

Garnet will be the abrasive used, as it's imperious the most acids which may become relevant during the final recovery

 

[ChopperGreg]

Best Ball Mill Media for Plated Silver Removal​

Link

Thank you

 

[stoneware]

Kurt your sales pitch needs boning up, that 20 liter pail contains the goods from over 1000 pounds of various types of boards.

Surface mounted caps, BGA's, Cpu's and whole ram sticks went through the shredder before tumbling.

I'm not trying to sell anything just sharing information, take it for what its worth, gold is a very soft metal usually platted over nickle to keep the gold from migrating into the copper.

Wave soldering picks up gold, the solder underneath cpu sockets are a good candidate to absorb some gold.

Using the small hatchet, I have it all.

By the way copper rubbing against copper will wear the copper wihtout some sort of lubricant,

 

[stoneware]

The gold is in with the copper,

How would you go about recovering the gold.

 

[orvi]

The gold is in with the copper,

How would you go about recovering the gold.

View attachment 53687

I will consider to shot this down with XRF in order to find out what you are actually doing. There are far to many assumptions in a row in your recovery venture.
First of all, I can say, that from modern motherboards, most of the gold is in the CPU and (usually) 2 BGA chips. This can comprise sometimes even 40-50% of total gold content on the average motherboard of WinXP computer. Then there are pins and smaller chips+transistors. This era MLCCs are junk for the most part - base metal types, some good ones on the some CPUs. Silver - mostly from caps and RuAg resistors. Really, not much of the stuff to be found here. Value lies in the tin, copper and gold - other precious metals are just added bonus.

And I would say it would be very difficult to get the gold bonding wires from the plastic via abrasion. Smearing is very bad thing which happens all the time when you have soft metal like gold.

Tested batch of connectors with pins running like 7g/kg gold was shredded to liberate free metal from the plastic. Loss of gold was about 2-10% on the plastic, depending on the type of plastic and shredding method used. No metallic pieces were left in the light fraction. Just smeared gold on the surface of the light stuff. It could even be measured with XRF. Second, once you have soldered something, gold cannot be reclaimed with abrasion.

Pick the cherries if you want to process something and sell the rest as lowgrade. No waste on your side, no hassle due to processing and nice material in your hand to play with. After catching goldfever, most important part to stay sane is to abandon processing unpopulated boards then, it will go easy. I also wanted to set up bigger shaft furnance scaled to around 100kg/day. I am glad that I never worked it out and never tried to build that thing

 

[goldshark]

My guess, is the Copper is well above the 75% range, so inquartation may work. Try a 1 gram digestion in Nitric, and see what happens. Small amounts will not lead to an excess of HMs. I don't know if you have a good microscope to see if there are foils coating the Copper, but would think this is the case, since you are grinding, and not chemically, or thermally alloying the metals. Mind you, the Au may be only microns thick, so may be difficult to identify on Copper, and the Nitric digestion may produce Au in very thin, flat particles, but should filter in a very fine filter. Please keep us posted on results.