Best options for this ash

[jord]

Hi, I have some bulk of incinerated ash. It has been pyrolised, Milled, run through an 80 & 100 mesh, magnets run through the ash then Incinerated to the colour in photos no black/carbon visible. The source is a complete mix of ic chips bgas included. Due to this reason I do not want to wash the ash as I am pretty sure I will wash way some fine gold wires from the bgas. I do not want to leach the entire ash as it seems a waste of resources. I was thinking of smelting the ashes with a flux of borax and soda ash 1:1 with fluorspar as a thinner if needed. My collector metal is going to be copper as I have an excess laying about, is there a rough guide to work out how much collector metal I should need? Also does it have to be poured into a cone mould as they seem to be quite hard to source in my area.

 

[goldshark]

Are you going to part with Nitric? This uses a lot of Nitric, about 4 times more then Silver. A cone mold can be made from steel by a welding shop, or if you can lay a flat bead, do it yourself. You can also use fine casting sand, but your conical metal slug will require a lot of cleaning. Cone molds are the best, steel or cast iron. Copper is not the desired metal, if you are going to cupel, requires too much heat, leading to PM losses.

 

[anachronism]

Jord what was the initial weight of the chips, and do you have any pics of them please?

 

[kurtak]

Hi, I have some bulk of incinerated ash.

Hi jord

You sent me a PM asking about this - sorry that I did not reply - just have not had time yet

Will "try" to do so this weekend when I have more time

Two things for sure

1) you absolutely do not want to try to leach that much ash !!!

2) you absolutely do not want to try to smelt that much ash !!!

This means you NEED to reduce amount of ash before ether leaching or smelting

I will post how to when I have more time (this weekend)

Jord what was the initial weight of the chips,

Please answer Jons question

Also - what kind of BGAs where mixed in the batch ? --- small BGAs like RAM BGAs or the north/south bridge BGAs - or some of both

And "about" how much of the batch was BGAs compared to other chips ?

Kurt

 

[kurtak]

one more question - if you put the ash in a 5 gallon bucket (or 20 liter bucket) how much would it fill the bucket

In the pic it looks like it would fill a bucket about 1/3 to !/2 full --- or is it more - or less then that (pics can be deceiving)

Kurt

 

[nickvc]

Could you make a small sluice as I think that would concentrate the values , you might have to run the material several times and pan to see if you have recovered most of your gold.

 

[kurtak]

Could you make a small sluice as I think that would concentrate the values , you might have to run the material several times and pan to see if you have recovered most of your gold.

There is a "bit" of a problem with running ash from BGAs through a sluice/concentrator table take can result in "some" gold lose --- which is why I asked the questions I asked

It is not a big problem just a 'bit" of a problem

Will post more when I get time

Kurt

 

[jord]

If I was to part yes nitric would be used, that was what I was wanting to avoid, I have casting sand but seems it would be easy enough to get a fabricator to make one up for me out of steel, also are my only choices for collector metal bismuth as I do not want to use lead

Are you going to part with Nitric? This uses a lot of Nitric, about 4 times more then Silver. A cone mold can be made from steel by a welding shop, or if you can lay a flat bead, do it yourself. You can also use fine casting sand, but your conical metal slug will require a lot of cleaning. Cone molds are the best, steel or cast iron. Copper is not the desired metal, if you are going to cupel, requires too much heat, leading to PM losses.

 

[jord]

Jord what was the initial weight of the chips, and do you have any pics of them please?

Inital weight was roughly 10-15KG I do not have an exact. The source of chips was literally every type of chip that comes off circuit boards more high grade than low, i estimate roughly 5-6kg bgas. I know they should be processed seperate but I fancied a challenge! This maybe be a bit ignorant of me but it's how I like it.

 

[jord]

Hi jord

You sent me a PM asking about this - sorry that I did not reply - just have not had time yet

Will "try" to do so this weekend when I have more time

Two things for sure

1) you absolutely do not want to try to leach that much ash !!!

2) you absolutely do not want to try to smelt that much ash !!!

This means you NEED to reduce amount of ash before ether leaching or smelting

I will post how to when I have more time (this weekend)


Please answer Jons question

Also - what kind of BGAs where mixed in the batch ? --- small BGAs like RAM BGAs or the north/south bridge BGAs - or some of both

And "about" how much of the batch was BGAs compared to other chips ?

Kurt

Most questions have been answered above, do you think it is possible to capture the gold with a concrete shaker and some fine ribbed matting, i also have a sluice box not large 70cm length, 18 cm wide but it is for capturing fine gold was thinking of using it to capture the run off from the table

 

[jord]

Could you make a small sluice as I think that would concentrate the values , you might have to run the material several times and pan to see if you have recovered most of your gold.

I do not have a pan, I have mesh screens down to 200 mesh, a concrete shaker table and small sluice box. What you are suggesting seems the most viable/ resource efficient

 

[jord]

one more question - if you put the ash in a 5 gallon bucket (or 20 liter bucket) how much would it fill the bucket

In the pic it looks like it would fill a bucket about 1/3 to !/2 full --- or is it more - or less then that (pics can be deceiving)

Kurt

The ash filled a 15L bucket and a little more, I do have more material to process but wanted to see if it was possible this way before I revert back to splitting the bgas(mix of all bgas mostly gold corner)

 

[Alondro]

Are you going to part with Nitric? This uses a lot of Nitric, about 4 times more then Silver. A cone mold can be made from steel by a welding shop, or if you can lay a flat bead, do it yourself. You can also use fine casting sand, but your conical metal slug will require a lot of cleaning. Cone molds are the best, steel or cast iron. Copper is not the desired metal, if you are going to cupel, requires too much heat, leading to PM losses.

Copper is best used if one plans to use copper sulfate electrolysis to capture the PMs as anode slimes. In that case, he'd need to remelt the copper slug and pour it into a rod shape, or else make shot. The sand stuck to it wouldn't be much of an issue in that case.

 

[jord]

Copper is best used if one plans to use copper sulfate electrolysis to capture the PMs as anode slimes. In that case, he'd need to remelt the copper slug and pour it into a rod shape, or else make shot. The sand stuck to it wouldn't be much of an issue in that case.

I have experience in running silver cells with success, I have two exactly like sreetips. But copper cell refining is not something I'm looking getting into at the moment. Due to that I believe copper will not be my choice of metal.

*Edit*
Just to add further to this, only way I want to recover copper is from shredded boards and seperating the particles with an eddy current seperator which I am trying to build and will post the design if I get success

 

[Shark]

Copper is best used if one plans to use copper sulfate electrolysis to capture the PMs as anode slimes. In that case, he'd need to remelt the copper slug and pour it into a rod shape, or else make shot. The sand stuck to it wouldn't be much of an issue in that case.

I melted my copper in flat, round anodes. I poured them in a 51/2 inch cast iron skillet that was made especially for baking one cookie per pan at a time. When I poured them I used a wedge under the pan so I would get one side thinner than the other that reduced the amount of copper that fell into the slimes. A copper cell is a great tool to have on hand.

 

[goldshark]

I do not have a pan, I have mesh screens down to 200 mesh, a concrete shaker table and small sluice box. What you are suggesting seems the most viable/ resource efficient

If you go the gravity separation route, use some Jet Dry, or other surfactant in the water. This will help to keep the small Au particles depressed. Classification of particle size is also paramount. Sieve through your screen, keeping the minus particles in one run, then after a clean up, run the other component..

 

[nickvc]

I do not have a pan, I have mesh screens down to 200 mesh, a concrete shaker table and small sluice box. What you are suggesting seems the most viable/ resource efficient

You can use many items as a standby pan , a plastic bowl would do, it’s only to check you are capturing your values not to clean them up.

But before you do anything wait for Kurt to come back as he may well have a better idea.

 

[jord]

If you go the gravity separation route, use some Jet Dry, or other surfactant in the water. This will help to keep the small Au particles depressed. Classification of particle size is also paramount. Sieve through your screen, keeping the minus particles in one run, then after a clean up, run the other component..

So i add a surfactant to keep the gold together? Then run through the mesh sieves in one run after that run I do a clean up and go again?

 

[jord]

If you go the gravity separation route, use some Jet Dry, or other surfactant in the water. This will help to keep the small Au particles depressed. Classification of particle size is also paramount. Sieve through your screen, keeping the minus particles in one run, then after a clean up, run the other component..

So i add a surfactant to keep the gold together? Then run through the mesh sieves in one run after that run I do a clean up?
*Edit*
I belive I could maybe use fairy liquid as the surfactant it contains sodium stearate?

 

[kurtak]

do you think it is possible to capture the gold with a concrete shaker

I have no idea what a concrete shaker is so could you post a pic of that - as well as a pic of the sluice box you have

Inital weight was roughly 10-15KG I do not have an exact.

Nice size batch

i estimate roughly 5-6kg bgas.

So about half the chips where BGAs ? --- if that is true - with 5kg you are looking at roughly 30 - 40 grams gold (plus/minus)

And for what it is worth there is about (plus/minus) 3 - 4 times more gold in the BGAs then in a "mix" of the other chips

To put that in perspective BGAs run "about" 6 - 8 grams per kilo (depending on mix/type) whereas a "mix" of other chips run about (plus/minus depending on mix) 2 grams per kilo

Keep in mind that when you process chips you will NEVER get 100% of the gold - there is ALWAYS gold lost in every step of the process - the goal in the processing is to minimize the gold lost in the different steps so that most of the gold ends up in the concentrates when you get to the point of leaching or smelting the concentrates --- & you MUST concentrate before leaching or smelting --- why ?

The ash filled a 15L bucket

Leaching - that is a LOT ash with a VERY small amount of gold distributed within it - so you need A LOT of leach acid (AR) just to wet that much ash - ALL that wet ash is going to turn to ULTRA fine MUD - it will be IMPOSSIBLE to filter/wash all the leach solution out of all that MUD --- therefore you "must" concentrate to get rid of the ash that creates the mud before leaching - or gold will be lost to leach solution that stays tied up in the mud

Smelting - again - that is a LOT ash with a VERY small amount of gold distributed within it - to slag off that much ash you need "at least" 2X flux (or more) plus collector metal - so - if you have a 15 liter bucket of ash plus two 15 liter buckets of flux = 45 liters - and you still need collector metal - a LOT of collector metal - why ?

To get good collecting of the metal - meaning so that the molten metal is able to rain down through the slag & pool in the bottom of crucible - you need the "smelt load" to be "at least" 30% metal - other wise you will have beads of metal hang up in the slag --- the "less" metal in the smelt load the more beads of metal that hang up in the slag

The smelt load - the smelt load is the combination of the ash + the flux + the collector metal

A bit about the collector metal - for best results in collecting your target metal (the gold bond wires) you want the collector metal to be "small" bits of metal so it can be well mixed in the smelt load so the collector metal makes contact with the target metal

Example; - if you just put you mixed ash/flux in a crucible with some large chunks of copper - bond wires that are close the chunks of copper will collect with the copper when it all gets molten - BUT - bond wires that are not in close contact with the chunks of copper will likely just melt into small beads that hang up in the slag

So you want the copper to be chopped into small bits so it can be well mixed in the smelt load making more of the copper in close contact with the bond wires

So - back to the smelt load - it needs to be (at least) 30% metal to get good collection (pooling in the bottom of the crucible once all molten) that means (roughly) for every 2 cups of ash/flux you need 1 cup chopped copper (the smaller the better)

So trying to smelt 1 bucket ash + 2 buckets flux + 1&1/3 bucket collector metal = 4&1/4 buckets to be smelted - resulting in only 1.5 ozt gold collected in a HUGE amount of copper

So - whether you smelt or leach you MUST get your ash reduced down to a concentrate

With chip ash there is no reason why you can't get a 15 liter bucket of ash reduced down to (plus/minus) a half liter of concentrates for better leaching or smelting

So my next posting will be about reducing that 15 liters down to a workable concentrate for leaching or smelting

Kurt