New - Process for separating ash from bond wires.

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Worms4u

Member
Joined
Dec 6, 2016
Messages
14
The other post on this topic really didn't answer what I was looking for.

So I've got a pretty large amount of pyrolized/incinerated IC chips. My initial plan was to put some ash in a bucket and fill the bucket up, then tip off some ash, and do that until I was only left with the heavy stuff at the bottom, and clear water.

Then I read about the heavy metals (chromium, I believe) that is in the chips and in doing what I was planning, I'd be putting that into the ground only to be kicked up later in the wind and probably causing lung problems.

So that's not going to work.

I did some research and found that Geo made a sluice (his famous 'poop chute') but I don't really have the room for that.

To my question - How do people separate the ash from the bond wires? If I used water + gravity I'll be generating a LOT of water I need to evaporate off to keep the ash in one place, which I don't think is feasible. Further I don't think I can pan out this amount of ash. Dunno, I'm kind of stuck.
 
It is fairly easy to recirculate water and use the same to process everything. You can go long route involved settling and decanting or faster one involving some filtering. I used old shirt which was quite good on catching most if not all ash. Waste washed ash can be dried and disposed anywhere you wish.

[youtube]http://www.youtube.com/watch?v=XBUiMjCzLuM&feature=youtu.be[/youtube]
 
I have burned (pyrolyzed) crushed and sifted a lot of circuitry over the years. I never ran the powders through a sluice but it was sifted to a -80 mesh and shipped to Sweden for smelting. (sorry for my contribution to your air quality Goran!) These powders always contained payable metals.

How do you know you are getting all of the values out of the powder? Have you ever dried, re-sifted, and sampled the powder that came off the table to see if it has gold. It would require a fire assay but IMHO it cannot hurt.
 
I do not know, perhaps some micro particles from solder may escape but I have dried and run again few batches couple of times. I do it kinda slow so I manage to get nearly all of it on a first run. Never found any significant quantity on second and subsequent runs.
 
I have had a few kilos of incinerated chip's from a board member.
Talk about a mess.
I did decide to go gravity separation first after ball milling to below 1mm as that amount of junk must act as a sponge and would definitely interfere with any process wet or hot. So am using the old blue bowl on it's absolutely lowest setting.
One kilo produced about 60L of dirty water that had to be settled in three different tanks .You have to change the water in order to see what is happening. but you could use this dirty water again for the first dirty pass on more material.
I took the concentrate and found it to be mostly finely divided copper which I managed quite a nice recovery from. If you have caught all the fine copper which is relatively light you should have caught most of the Au which is much heavier.
I am getting my assay furnace up and running so I can run a series of test on samples from various points. such as starting material and waste water sediment.
Quite a demanding material to run.
on larger lots I will smelt the concentrate and flux well to obtain a straight alloy before I decide a rout for recovery.
It might be a good alloy to use with my karat material instead of silver making it economical to digest.
 
Ball Milling to below 1mm is not anywhere near fine enough, if you look at the material through a microscope you will see many bond wires still caught in the epoxy-carbon at that scale. I find that everything has to go through a 60-mesh sieve before the vast majority of bond wires are freed.

The problem with not milling the material fine enough is that gravity separation doesn't work well on bond wires with carbon parachutes still attached.

I also find that if I sieve to 100-mesh I get too many bond wires caught by the sieve, 60-mesh seems to be the sweet spot for pyrolized and ball milled ICs.
 
4metals said:
I have burned (pyrolyzed) crushed and sifted a lot of circuitry over the years. I never ran the powders through a sluice but it was sifted to a -80 mesh and shipped to Sweden for smelting. (sorry for my contribution to your air quality Goran!) These powders always contained payable metals.
You are forgiven, you did send us the gold. :mrgreen:

Göran
 
g_axelsson said:
4metals said:
I have burned (pyrolyzed) crushed and sifted a lot of circuitry over the years. I never ran the powders through a sluice but it was sifted to a -80 mesh and shipped to Sweden for smelting. (sorry for my contribution to your air quality Goran!) These powders always contained payable metals.
You are forgiven, you did send us the gold. :mrgreen:

Göran

:lol: :lol: :lol:

Kurt
 
kernels said:
Ball Milling to below 1mm is not anywhere near fine enough, if you look at the material through a microscope you will see many bond wires still caught in the epoxy-carbon at that scale. I find that everything has to go through a 60-mesh sieve before the vast majority of bond wires are freed.

The problem with not milling the material fine enough is that gravity separation doesn't work well on bond wires with carbon parachutes still attached.

I also find that if I sieve to 100-mesh I get too many bond wires caught by the sieve, 60-mesh seems to be the sweet spot for pyrolized and ball milled ICs.

I use 80 mesh - bonding wires go through & no carbon stuck to them & being a bit finer it washes/concentrates better

Kurt
 
kernels said:
Ball Milling to below 1mm is not anywhere near fine enough, if you look at the material through a microscope you will see many bond wires still caught in the epoxy-carbon at that scale. I find that everything has to go through a 60-mesh sieve before the vast majority of bond wires are freed.

The problem with not milling the material fine enough is that gravity separation doesn't work well on bond wires with carbon parachutes still attached.

I also find that if I sieve to 100-mesh I get too many bond wires caught by the sieve, 60-mesh seems to be the sweet spot for pyrolized and ball milled ICs.
The ball mill douse not really power up the main body of the material, that would take an impact mill I think.
The oxides and a lot of ash shatter more easily than the metal, so I just milled and sieved.
The great thing about gravity separation is you do not have to get a good separation, if you can simply float off the very fine particles which shatter easily and any thing soluble you are on the right path. all the more robust elements will stay relatively untouched,We do not want to flatten any bond wires do we.so gently gently.
I am still testing but I have not found any value in the waste which is a good sign.
 
justinhcase said:
The ball mill douse not really power up the main body of the material, that would take an impact mill I think.

If you do the pyrolysis to completion (insure ALL the volatiles are burnt out of the epoxy & it is FULLY carbonized) a ball mill does a VERY good job of turning the main body (the epoxy casing) of IC chips to powder - fine enough powder that 85 - 90% should pass through a 80 mesh sifting screen

The 10 - 15% over size (that doesn't go through the screen) goes back to the (ball) mill for re-milling & sifted again

If you are getting more then 10 - 15% over size --- you ether did not run it in the mill long enough - or - you did not do the pyrolysis to completion so the chips are not carbonized enough to make them soft enough for the (ball) mill to bust them down to powder

Also - if you are using a cement mixer as a ball mill - you have to learn to adjust the angle of the mixer to different angles to get it preform the task you want it to preform at the different stages of the milling

In the beginning of the milling - when the chips are still large/whole chunks - you want the mill to preform a "crushing" task - so you want the angle of the mixer in more of an "up right" angle - this allows the balls to be lifted up & around at the back of the mixer drum - because they are "lifted" up to the top (of the back of the drum) they then come "crashing" down on the chips at the bottom of the drum - thereby "crushing" the chips

Then - once the chips are crushed down in size - you want to "lower" the angle of the mixer so the balls are not lifted as much (but still lifted some) because you want them to stay more in the bottom of the drum where they "roll" causing them to now preform more of a "grinding" task

You might have to adjust the mixer angle back & forth a few times during the milling - it just depends on what you see happening with the milling during the milling

The other thing when ball milling - you want a load of different size balls - you do NOT want all one size balls - my "ball load" is made up of 1 inch balls - 1 1/4 inch balls & 2 inch balls (having mixed ball sizes is "important" to proper mill operation)

Finally - you want to have your material (being milled) to ball ratio with in a ball park of what is right for the mill --- not enough material - during the "crushing" task - you wont get enough material lifting with the balls & instead of good crushing you will just get balls banging against balls

To much material & it will hinder the balls from rolling like they should during the grinding task

Bottom line - a ball mill works VERY well for milling IC chips - its just a matter of understanding what/how it is supposed to work - & then getting familiar with operating it

Takes about 2 - 4 hours &/or 3 - 6 mill runs

Kurt
 
I have a set of lab earthen ware jar's and ceramic balls that have razed gully's running around the inside of the jar's so you can leave a slight gap between the mill balls and the jar thus. control the size of particle that way. Can be very delicate which is where you want to start, you can always increase force.
My mill has eroded and shattered some of the silicon wafers but left most intact. no epoxy left,but it would take a big old ruff cement mixer with big steel balls to grind them. :D
Then I thought you would be in danger of flattening gold wires so they would float and catch eddy's.
I thought all the people who work gold ore are quite keen to move from ball mill to impact mills for that reason
I am upgrading the motor on my running rollers and have the parts for one twice the size with a steel set up.
But I bought a flow drill to attach all the fittings to the frame and my drill press just turned it with out it heating up. :roll:
 
So I can assume that no-one who crushes the pyrolyzed material to powder and screens it has ever dried and assayed the tailings that come off the screen?

Do you at least save it?

I have always said one of the keys to profitability is to never send out any material that has not been homogenized and properly sampled and assayed. A second key is never throw anything that has been through refining processes away without assaying it!
 
4metals said:
So I can assume that no-one who crushes the pyrolyzed material to powder and screens it has ever dried and assayed the tailings that come off the screen?

Do you at least save it?

I have always said one of the keys to profitability is to never send out any material that has not been homogenized and properly sampled and assayed. A second key is never throw anything that has been through refining processes away without assaying it!
Yes I have saved it all and am collecting supply's so I can do a good run of fire assay's.
I also asked for the chap who sent me the lot and did the pyrolysis to invest in an independent assay.
that way we can have a good base line to work with, a minimal target and a chuffed look if you ever exceed expectations. :D
 
Goran,

Yes the gold stayed in Sweden but the payment for a very high percentage of the metals, precious and copper, came back to me. I seem to remember an accountability in excess of 98%. However I am likely guilty of contributing to the Rönnskär's nose syndrome!

But I will sleep better now having been forgiven of former perceived sins by a resident Swede!
 
No worries, 4metals, the Rönnskär nose is from exposure to arsenic and the small amounts of trace in IC:s are negligible compared to the amount of arsenic in the sulfide ores in the area... There is a reason there is an arsenic filter at the smelter and it's big as a house.

Here's a natural arsenic specimen I found on a mine dump a couple of years back. 6.8 kg of metallic arsenic in one piece. There is some calcite too but my guess is that there is more than 5 kg of arsenic in it. It probably contains quite a lot of silver too.
6.8 kg arsenic.jpg
Not a beautiful crystal but as a mineral specimen it's really rare with botryoidal arsenic in that size. It's all the rounded dark pieces with the center between the two sides filled up with some calcite and pale green fluorite. When I found it my hart skipped a few strikes.

Göran
 
4metals said:
So I can assume that no-one who crushes the pyrolyzed material to powder and screens it has ever dried and assayed the tailings that come off the screen?

Do you at least save it?

I have always said one of the keys to profitability is to never send out any material that has not been homogenized and properly sampled and assayed. A second key is never throw anything that has been through refining processes away without assaying it!

4metals

Just curious if your talking about all the silver that is being left behind in those tailings?Thanks in advance.



modtheworld44
 
Talking about any PM's. In theory silver will also be caught in a riffle I am talking about metals ground to super fine powder from the crushing process and blow off the table. It may be very little and not be payable, but then again it may be payable.

Finely crushed dirt looks like dirt, our eyes cannot tell the difference. A fire assay can.
 
4metals said:
Talking about any PM's. In theory silver will also be caught in a riffle I am talking about metals ground to super fine powder from the crushing process and blow off the table. It may be very little and not be payable, but then again it may be payable.

Finely crushed dirt look like dirt, our eyes cannot tell the difference. A fire assay can.

Simple rule to follow Save, Sample, Test and Assay.
Why throw away potential values from your hard work :shock:
 
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