Unique method to metalize E-waste milled powder

[4metals]

When I generated a lot of sweeps as an operating refinery I was able to ship out multiple drums of low grade powder to a smelter in Europe. Boliden in Sweden is one I remember well. The ash would yield in the neighborhood of 1/2 ounce of gold per drum which was typically 400 pounds. So something around 0.075 grams per pound. This was just from the fines after incineration and sifting. At that concentration, and at the time $300 gold, it was not worth recovery in house.

The process used was to ash the circuits to burn off all of the plastics and, if the feed rate was slow enough, burn off the toxins in an afterburner. The resulting ash was very much like the ash in the video’s after the torch ashed them. That material was sifted through a screen to separate the metallic fraction from the powder. The metallic fraction was melted into bars and assayed and the customer was paid on the recovery value of that bar. The powder was also assayed but was never concentrated enough to process in house.

If I had a rotary furnace at the time, I think the rotation of the load would have allowed the molten copper to recover the small percentage remaining in the powder as well. Ironically I had customers that came back to me after using refiners with a rotary saying my returns were better. So I never had issues with not paying on the powder.

To address your issue with the cost of crucibles why don’t you start a thread discussing how the crucibles used in the video’s are made. Seeing the simple shape they use, I think the proper mix of ingredients is all you need to confirm to make your own.

 

[Ayham Hafez]

When I generated a lot of sweeps as an operating refinery I was able to ship out multiple drums of low grade powder to a smelter in Europe. Boliden in Sweden is one I remember well. The ash would yield in the neighborhood of 1/2 ounce of gold per drum which was typically 400 pounds. So something around 0.075 grams per pound. This was just from the fines after incineration and sifting. At that concentration, and at the time $300 gold, it was not worth recovery in house.

The process used was to ash the circuits to burn off all of the plastics and, if the feed rate was slow enough, burn off the toxins in an afterburner. The resulting ash was very much like the ash in the video’s after the torch ashed them. That material was sifted through a screen to separate the metallic fraction from the powder. The metallic fraction was melted into bars and assayed and the customer was paid on the recovery value of that bar. The powder was also assayed but was never concentrated enough to process in house.

If I had a rotary furnace at the time, I think the rotation of the load would have allowed the molten copper to recover the small percentage remaining in the powder as well. Ironically I had customers that came back to me after using refiners with a rotary saying my returns were better. So I never had issues with not paying on the powder.

To address your issue with the cost of crucibles why don’t you start a thread discussing how the crucibles used in the video’s are made. Seeing the simple shape they use, I think the proper mix of ingredients is all you need to confirm to make your own.

Yes you alright that what am thinking, the recipe to make same crucibles,I have done some researches about it, will make new thread and share the recipe that I think its suitable.

I have incinerated IC chips hundreds times, but I don't get metallic beads after finish incineration, I use natural gas torch with steel tawa to incinerate till get fully white ash, so how I can get metallic beads from incineration? Or I just have to increase the torch temperature to make small metal parts crump together?

When I thought about rotary furnace which I think its the best for E-waste smelting because of the rotation feature, I remember my experience with rotary furnace in lead smelting industry, when we build new rotary furnace for lead smelting, first 3 or 4 batches can't reach more than 60% of original recovery rate because lead bean absorbed by the refractory bricks till it been saturated, in lead industry its not an issue but in E-waste smelting it will be a big issue since the absorbed smelted value is too high

 

[4metals]

E-waste smelting it will be a big issue since the absorbed smelted value is too high

True to some extent but the ratio of copper to precious metals makes most of what is trapped between the refractory bricks copper. And you could grout the refractory with clay graphite to minimize the retention.

The crushing and sifting to a fine mesh will assure most of the values remain in the oversize. But assaying the powders will tell the story.

 

[Ayham Hafez]

True to some extent but the ratio of copper to precious metals makes most of what is trapped between the refractory bricks copper. And you could grout the refractory with clay graphite to minimize the retention.

The crushing and sifting to a fine mesh will assure most of the values remain in the oversize. But assaying the powders will tell the story.

Is Alumina refractory bricks 70% is good for e-waste smelting or I have to use chromite or magnesium refractories bricks?

 

[4metals]

Alumina refractory was all that was readily available when I used it (remember I am old) but if I remember correctly it will exceed the temperature limits your furnace will hit, withstanding up to 1650ºC. Gold melts at 1060º or so and I always ran a furnace at 1100ºC because copper required a bit more heat. But you are essentially melting copper.

 

[Ayham Hafez]

Alumina refractory was all that was readily available when I used it (remember I am old) but if I remember correctly it will exceed the temperature limits your furnace will hit, withstanding up to 1650ºC. Gold melts at 1060º or so and I always ran a furnace at 1100ºC because copper required a bit more heat. But you are essentially melting copper.

Do you think Alumina bricks much resistance to fluxes than salamander graphite crucibles?

 

[4metals]

All refractories succumb to cryolite of fluorspar it's just a matter of time. A crucible goes bad and you take it out and put in another. When a refractory lined rotary goes bad it is a project. Remove the old brick, chisel off where flux leaked through over time and get back to bare metal, and then re-line the furnace with refractory brick. So there is no comparison.

 

[Ayham Hafez]

Alumina refractory was all that was readily available when I used it (remember I am old) but if I remember correctly it will exceed the temperature limits your furnace will hit, withstanding up to 1650ºC. Gold melts at 1060º or so and I always ran a furnace at 1100ºC because copper required a bit more heat. But you are essentially melting copper.

Another thing want to ask you, you mentioned before in "Smelting" thread, that depopulating PCB'S and process items separately much better that just process PCB without depopulating, but I didn't understand why? Depopulating and sorting took most of the time, and at the end we need PCB copper to collect the PM's , so why just process the PCB with its components in one step?

 

[4metals]

This is a question I would like to hear from others on as well.

When I refined the only boards I depopulated were boards with ceramic IC's because they are alumina ceramic and they do not turn to ash or melt in a fluxed furnace and tend to mess things up. Plus they do refine well in acid and were worthwhile to process separately.

Other things like heat sinks and obvious parts that do not have any value to refine also came off.

 

[Ayham Hafez]

Another thing want to ask you, you mentioned before in "Smelting" thread, that depopulating PCB'S and process items separately much better that just process PCB without depopulating, but I didn't understand why? Depopulating and sorting took most of the time, and at the end we need PCB copper to collect the PM's , so why just process the PCB with its compon

This is a question I would like to hear from others on as well.

When I refined the only boards I depopulated were boards with ceramic IC's because they are alumina ceramic and they do not turn to ash or melt in a fluxed furnace and tend to mess things up. Plus they do refine well in acid and were worthwhile to process separately.

Other things like heat sinks and obvious parts that do not have any value to refine also came off.

More than one month thinking of how I can upgrade my process, I'm trying to reach to optimum recovery rate with minimum time, time and labor cost are the most valuable things for me, the process that I think it will be the best is:

1- separate steel, aluminum, ceramic ic chips and copper coils from PCB manually
2- shred the PCB into small pieces
3- pyrolizing shredded pieces
4- milling the pyrolized stuff with rod mill
5- incinerating
6- mixing incinerated ash with flux without washing or panning
7- smelting to get metals shots


Hope other members share their advices

 

[Ayham Hafez]

In case we are just focusing on gold, is it a good idea to just leach the incinerated PCB powder in Jinchan? Treating the E-waste similar to high concentration gold ore, after getting the gold we can just smelt the E-waste ash to get impure copper and sell as it is.

 

[kurtak]

In case we are just focusing on gold, is it a good idea to just leach the incinerated PCB powder in Jinchan?

Per the bold print - I have no idea what "Jinchan" is - could you please explain

In other words - is this (Jinchan) supposed to be some kind of leach that is selective to gold only

Kurt

 

[Ayham Hafez]

Per the bold print - I have no idea what "Jinchan" is - could you please explain

In other words - is this (Jinchan) supposed to be some kind of leach that is selective to gold only

Kurt

Jinchan is substitute of sodium cyanide, eco-friendly, selective for gold and silver only

 

[Yggdrasil]

Jinchan is substitute of sodium cyanide, eco-friendly, selective for gold and silver only

Do not believe what they tell in their web sites and ads, it is not entirely correct.
Most of these magic concoctions are Ferro or Ferri Cyanides.
They often have very imaginative descriptions of their products in their MSDS.
For example in stead of saying NaOH they call it Sodium Oxide

 

[kurtak]

First off I love the way they suck you into watching. Start with a picture of refined bars neatly stacked.

Then after watching the entire video, you see the yield;

Kurt

 

[kurtak]

Jinchan is substitute of sodium cyanide, eco-friendly, selective for gold and silver only

Don't believe everything a company that is trying to sell you - their only real interest is in making money selling you their product & they really don't care if &/or how well that product actually works

If this is anything like the Eco-Goldex product (& it likely is - just sold under a different name) don't waste your money on it

Could you provide a link to their web site

Kurt

 

[Ayham Hafez]

Don't believe everything a company that is trying to sell you - their only real interest is in making money selling you their product & they really don't care if &/or how well that product actually works

If this is anything like the Eco-Goldex product (& it likely is - just sold under a different name) don't waste your money on it

Could you provide a link to their web site

Kurt

Their website:

http://www.gxshgk.com/senhe_en/index.php

In Africa they are well know, most of the gold mining market share is for them, today I contacted them and mentioned the following:

"
In the recycling industry, one of our major clients is USS from Russia
www.uss.ltd

Our regular products have an active ingredient of 30%, and electronic recycling requires 35% "

 

[Yggdrasil]

Their website:

http://www.gxshgk.com/senhe_en/index.php

In Africa they are well know, most of the gold mining market share is for them, today I contacted them and mentioned the following:

"
In the recycling industry, one of our major clients is USS from Russia
www.uss.ltd

Our regular products have an active ingredient of 30%, and electronic recycling requires 35% "

It would be much cheaper to buy straight Ferro or Ferri Cyanide.

 

[Ayham Hafez]

It would be much cheaper to buy straight Ferro or Ferri Cyanide.

I bought potassium ferricyanide from Egypt for 34 USD per kg, didn't find industrial grade, Jinchan is less than 2 USD per kg, also as I know ferricyanide act as a gold oxidizer so it needs cyanide to dissolve gold.

 

[Yggdrasil]

I bought potassium ferricyanide from Egypt for 34 USD per kg, didn't find industrial grade, Jinchan is less than 2 USD per kg, also as I know ferricyanide act as a gold oxidizer so it needs cyanide to dissolve gold.

No, it needs UV light.
Then the CN ion will be freed to do the job.
Ferrous Cyanide is easier, if I remember correct.
These things can be found relatively cheap on Alibaba if you do not find it locally.