Sorting for refining e-scrap

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4metals

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Sorting, the process of separating your e-scrap scrap based on how it will be best processed.

I always try to think of things that make life easier, so naturally I apply this train of thought to this forum as well. One of the things that new members and old members alike may find confusing is determining a best process for a specific type of material. So it was my intent to start this thread with the hope that we can all input information that may eventually lead to a useful flow chart for sorting e-scrap prior to refining it.

I am not looking to add things like karat gold or sterling silver to this list, these high grade materials are pretty straightforward and well covered on this forum. Nor am I looking to detail the specifics of AP or a sulfuric cell here, simply to determine what different materials are processed together.

So what I am looking for is the thought process our members go through when they arrive home with a trunk full of e-scrap. What are the different sorting bins you have when you disassemble components to process? How do you group different boards, fiber vs plastic, burn vs strip, or whatever criterion you use to separate materials for processing.

One of the good things about refining is there are many different pathways to get to the same end. This also provides for one of the more confusing aspects of refining, what method is best? So if we can begin to describe the different bins or sorting piles to break scrap down based on how it will be processed and how you process it, maybe we can use this thread to generate a flow chart of sorts to determine what is grouped together and what method you are using to process it.

If we all pool our logic and our methods for sorting and processing different types of scrap, we can all learn from each other, and make life easier.

So........ who's first?
 
well I can give my half hay penny but from my point of view there is very little e-waste that is suitable for the small scale refiner.
Ram , old processors and old mobile phones would be the only things I would incinerate smelt and leach.
the fingers are nice and easy but you need a lot to make it worth while, which I find with all e-waste.
Heavily gold plated parts are good to store but the only really effective method for them I have seen is Cyanide leach.
The other 99.9% I just stack up in high grade(any thing with visible value such as capacitors or chip's )and low grade copper (all the power supply's and coils)
My agreement is large dumpy bags such as is used for building aggregate. very patient partner as I still have not enough for a shipment after two years, I am at about 3/4 of the dump sack.
I did run trials on recovered components. picked bit's off for a week, I did a time and effort study against returns ,knocked that on the head after that week. :D
 
Ok, thanks for going first Justin but we need to come up with a system which will help this all make sense easily.

So in your operation:

Bin A ram, old processors and old mobile phones. Treatment method; incinerate, smelt and leach

Bin B trimmed fingers and lead trim. Treatment method ?????

Bin C heavily gold plated parts. Treatment method? Hold for whenever
Are these separated by magnetic, copper or brass or stainless categories?

Bin D high grade, capacitors, chips. Treatment method?

Bin E Low grade copper Treatment method. Accumulate and sell as is.

Eventually it would be nice to give a descriptive name to each bin so we can all comment on what goes in each specific bin, but lets see how this plays out and how much response we get.
 
Its funny you would bring this up 4metals. I remember after about a year of studying I realized that everything we run into needs to be brought down to its basic form, these are foils, powders, or bond wires. When I sort, I think about where I need to end up.

While I still consider myself an amateur, I think I've got a good handle on what needs done how. Everything is sorted by IC chips, pins, fingers, BGAs. From there I have little sub categories. Pins I sort by copper, mixed lightly plated, mixed heavy plated, IDE, and last, plated components like transistors and laser diodes.

I am excited to hear from the pros on this one.
 
Every piece of Electronic Waste I get in that has precious metals on it goes in my containers that are bound for Sipi. I do pick things off the boards to process myself like fingers and some packages like BGA but everything else goes in the Gaylord box, even some extra copper and small LCD screens.

And of course all the different types of base metals have their own container and I just sell that stuff to the local (Padnos) scrap yard. I won't take the time to work on the problematic or less yielding scrap, it's not worth my time, I'll get paid for it from Sipi and I won't have lost any values or generated an excess of chemical waste that I would then have to deal with.

When I first started I thought I would process everything I could get my hands on that contained gold but it was too easy for me to instead, keep it simple and efficient. I see a line to not cross there based on my facility, capabilities and being practical. Some of it just ain't worth the battle.
 
When I sort, I think about where I need to end up.

And this is essentially the whole enchilada! Where you need to end up and how to get there with less effort. (meaning, less chemical, less waste, and less time!)

Can you detail what you call your bins? And how you break down individual bins further based on what criterion? And finally what method you use for each type.

Eventually enough input here can result in members referring to specific chips and components as Bin X material. That is where I would like to take this.

Some of it just ain't worth the battle.

But knowing which battles to fight and which to pass on is a learning curve. And we get there by sorting as you did at the outset.
 
When i would pick up and tear down escrap. I kind of shot myself in the foot a bit with it. As I would tear down the computers and servers. Throwing motherboards in one box, peripheral cards and ram in another box. Processors in 3 boxes (ceramic, black, green).

I would then take and depopulate the motherboards, throwing my ic chips in their own bucket (dip, and flat packs -which would be sorted by size later *) mlcc and ta caps would be put in their own buckets, and bga's had their own bucket.

*that is where I shot myself in the foot, touching the same product more than once creates that much more time devoted to it, time is money, and escrap there isnt a lot to be had doing it that way.

So it would probably be best to remove the boards, strip all the components and throw them in their buckets:
**processor buckets
-ceramic
-black fiber
-green fiber
**ic chips
-dips
-quads
**fingers
**pins
-full
-partial
-solder
-magnetic
**bga's
**mlccc's
**ta caps

I know there are other categorised buckets i should have had, but, i threw in the escrap towel long ago. (unless other's are breaking it down and sorting it for me, of course)
 
Me! Me! Me! Me! Me! Me! I can start.... Oh.. too slow... :cry:

I started off by collecting every scrap that had a hint of gold and to keep acid costs down the only thing I processed was fingers. The only way I knew to process then was dissolving base metal with nitric and collecting the gold. This was back in the pre-forum days.
At that time I didn't know of anyone buying electronic scrap so anything picked cleaned went to recycling. Soon I realized I got more scrap than I had time to fully process and I started to prioritize, only picking pieces with decent gold. I started to skip PCI and ISA connectors.
Later on I found out the local scrap dealers paid good money for iron, aluminum, cables, brass, copper, stainless steel, lead batteries and any circuit boards so naturally that was the fractions I sorted in, picking off any good gold on the boards and no one noticed.

When I found the forum I realized I had missed quite a lot of the gold. At the same time they lowered the price on circuit boards so today I sort the circuit boards in three parts :
- Low value boards like power supplies, TV-boards, power electronics... and so on. These I sell in 50 kg batches.
- Good value boards like mother boards, hard disk boards, boards with a lot of IC:s... and so on. I don't care to remove any gold at all from these boards, just any non-gold containing parts like cooling fins, large capacitors... Any components removed here goes to the low value bin.
The good value cards are stored for later processing or for sending off to a smelter where I can get paid on content. There are no good buyers in my area and I would get the same price for this as for power supply cards.
- Stuff to process. Here is a mix of different things. Anything large and gold plated like microwave components and connector housings is placed in a box waiting for the next run of the sulfuric cell. Memory SIMM, CPU:s and mobile phones also ends up here. Basically this is what I have time for in the foreseeable future and if I get too much the border between "Good value" and "Stuff to process" will move to produce a balance.

The rest of the scrap is still sorted in the lots the scrap yards buy things in. For example, my buyer doesn't sort zinc from aluminum so all white non-magnetic metal except for stainless ends up in the same bin.

Some complex scrap is processed slightly, I had a couple of server power supplies that had gold fingers, some logic boards and MLCC:s. The gold fingers were cut off, the logic boards broken off and put with the Good value cards and the MLCC:s I could reach easily enough was cut off before the bulk went into the low value box.

The iron is mostly an annoyance, I filled up the car today with old computer chassis and 250 kg made me $20. I needed the space more than the money, tomorrow I'm filling up the car with old printers and that will result in quite a lot of iron scrap again.

When it comes to refining I don't have a lot of rules I follow, usually I start with quite specific treatment of scrap depending on what it is. Then as I progress I can combine the lots unless I want to do some assays on specific components or refining for a client.

- If it is fully plated on thick metal and everything can be accessed by a liquid, cyanide or sulfuric acid cell.
- If it is plated on thin copper, copper chloride leach to extract the gold foils.
- If it contains gold bond wires in plastic, incinerate and pan.
- If it is ceramic and got iron pins, hydrochloric acid to remove iron and solder.
- If it is ceramic and most base metals are mostly gone, aqua regia.
- If there is tin or indium on it, hydrochloric to remove it, then sort it again.
- If the precious metals are covered in plastic material, incinerate (dipped MLCC:s with pins for example)
... and so on, sometimes it is possible to merge two lots into the next processing step, for example foils from fingers, panned bond wires and gold sludge from a sulfuric cell can easily be dissolved in AR together. But sometimes mixing two lots can produce strange results... that builds experience. :lol:

I have the following bins I sort small electronic things in. Bins is a bit vague and can go from a small jar to large boxes.

Gold :
- Bin 1. Metal pins fully or mostly gold plated, no plastics (Currently 30-40 kilos). Too much metal to economically dissolve the metal. First plan, melting and copper cell but scrapped that. Second plan sulfuric acid tumbler cell on hold. Third plan cyanide leaching and researching it currently, looking good.
- Bin 2. Good plating contacts, mostly leaving it on boards unless the rest of the board is low value. Pulling pins while watching TV and putting it in bin 1. Having 10-20 kilos of it in storage.
- Bin 3. DIL IC:s, sell or process myself. Only stockpiling at the moment.
- Bin 4. Surface mount IC:s. Stockpiling but will process with RAM when I have a couple of kilos for a decent batch. Processed according to Patnor method.
- Bin 5. plastic BGA, Processed according to Patnor method when I have a kilo or more. I keep this separate from Bin 4 since there is only gold and trace copper inside, no lead frame to mess with.
- Bin 6. RAM, In small batches I would depopulate in HCl, collect IC:s and MLCC:s separately, circuit boards goes to copper chloride bath.
- Bin 7. CPU:s, Sort and process according to model and sell to collectors if possible. Modern CPU:s might end up with Good boards in the end. This is a subject of it's own.
- Bin 8. Mobile phones and similar high end scrap. I'm collecting for processing via smelting. Not there yet. Might go with Good boards in the end.
- Bin 9. Large plated objects. Collect a couple of kilos then run through sulfuric cell.
- Bin 10. Other gold containing components, throw in a box and look at it some other time. Might go to smelting with the mobile phones. Anything I don't have enough of or don't know what to do with ends up here.

Silver :
- Bin 11. Keyboard mylars. Collect for incineration or other treatment.
- Bin 12. Silver contact points from relays and breakers, collect, dissolve in nitric and cemented on copper.

Palladium :
- Bin 13. MLCC:s, When convenient I pick off some MLCC:s and collect. Usually process when I have 2-3 hg or more. A long soak in HCl (months), then nitric acid, silver as chloride, denox, cement and collect PGM concentrate.

Other :
- Bin 14. Tantalum capacitors. When I feel for it and there are easy pick on boards I remove some other components I usually pick these off too for selling.

If I would be doing this for economic reasons I would sort in low value boards to sell locally and high value boards to send away... yeah, that's about it. I might keep some high end stuff just as some CPU:s or fingers might be faster to payout if I process it in house. Then I would have gold in my hand in a few days instead of money in a month or more.
The reason I sort in so many bins is that I want to try different methods and to get a first hand knowledge on how much values there are in different types of scrap. If I know how much I can expect from a DDR3 RAM then I can buy scrap, collect a larger batch and send out for processing. There is more money in refining, toll refining or collect larger batches than in ripping apart computers one at a time.

As has been said before, if you need to sort scrap component by component then you will never earn any decent money. Smelting can process tons of scrap at a time so for us there basically is only high grading and collecting left that we can do with mixed scrap.
The sole exception is when we get already sorted scrap that we can process straight away, like CPU:s or RAM.

So far I'm only a hobby refiner and have kept all metal I have refined. I'm getting closer to my first ton of good boards and is still collecting.

Being a hobby refiner, nothing I do needs to make economic reason...

A long post but when I started to write I couldn't stop. :mrgreen:

Göran
 
Ok this can get confusing real fast and it makes me realize something else we don't have, a component dictionary with pictures. It wouldn't surprise me if different members are referring to the same types of circuitry with different names.

If anyone else thinks this would be worthwhile to have, say so here and I will start a sticky thread in the "Types of PM scrap" section. Something like the "Definitive GRF e-scrap component acronym list, with pictures."
 
You can also make it a whole lot simpler but whilst this won't be popular I'm sure Chris would possibly agree.

1. Worth doing.
2. Not worth doing.
 
hi . i dont know where to post it. i have ram fingers . should i use hcl + a drop of h2o2+ aquarium pum or just nitric acid+gentle heat to remove gold foils ? which one is more efficient and less time consuming?
 
Salman,

Please post your question in the help needed section. When you do, I will delete it from this section. If you post in the proper section you will likely get your answer.
 
anachronism said:
You can also make it a whole lot simpler but whilst this won't be popular I'm sure Chris would possibly agree.

1. Worth doing.
2. Not worth doing.

My first sort for "e-scrap" is:

1. Worth selling (for resale after testing).
2. Not worth selling (not worth testing based upon resale value).

Primarily by doing ebay searches and other searches of similar items that have sold or "not sold"
at a reasonable price to justify my time and materials to test, catalog, photograph, price, list, sell, pack and ship.

Then I drop into process of sorting for recycling or processing for refining. 8)
 
Here's my two cents :)

I sort boards into rhos and non rhos compliant board type.
I then use a lab hot plate to de populate the components off the boards.
I sift the components into large pieces and fines.
The large pieces are sorted by type/garbage. And the fines are heated on the hot plate in a piece of old steel screen. I then shake off the melted solder till no more comes out. Collect the solder in pools and screen and treat the fines in hcl. The remaining material is a mix of pins and mlcc and resistors. The rhos board solder is checked for silver/ bismuth. Mabey a Cupel material? The lead solder is sold as scrap. It goes without saying a respirator needs to be worn when playing with melted solders righr :| also I pull off All the capacitors before heating the board.think pop corn but with hot aluminium and acid flying everywhere. Gold fingers/ boards are kept. Rest is mixed with low grade junk and sold at scrap yard.
Hope this helps someone.
 
I sort by my interpretation of low, mid and high grade boards. Low grade boards are things like power supply boards and boards from old TV's, microwaves and other low end appliances (very little to no gold). Mid grade is mother boards, flat screen TV's and monitors, dvr's, satellite and cable boxes (some gold but not much). High grade is daughter boards, peripherals, ram, military and medical (good gold content by weight).

Low grade boards are stripped of non-PM metals like aluminium and copper for recycling and any small PM bearing items.

Mid grade boards are cherry picked of any PM bearing parts and are down graded to low grade. Any boards with gold plated traces are trimmed and gold bearing parts are added to the high grade boards.

High grade board are depopulated of non-PM bearing items and prepared for other treatments.

My preferred processing method is CuCl2 and oxygen. Almost all of the PM bearing parts listed above are treated with CuCl2 in large batches of fifty pounds or more at a time. Since I have some years of practical experience with the process, I am used to the mess it creates as far as soluble and insoluble oxides and chlorides and have developed my own ways of dealing with it. I have found that tin, in a very oxidized, acidic environment will convert from tin chloride to tin oxide. Just like stannous chloride will "go bad" over time due to oxidation from the air, the stannous chloride created in the AP process will oxidize from the air bubbled through the solution. This tin oxide will precipitate out of solution as an insoluble oxide salt. Keeping air bubbling through the solution continuously helps this process along. All the higher reactive metals will oxidize given enough time and drop out of solution with the exception of a couple of metals including iron.

For this reason, I process any iron bearing PM scrap (processors, gold plated Kovar) in AR exclusively.
 
I'm a bit late on my input for this thread.


First, I'd take off certain things like steel, aluminum, plastic, copper windings, glass and electrolytic capacitors.

When I started, everything got chiseled off and thrown into a bucket of HCL to remove solder, then into AP to dissolve most of the metals. When I finally get around to it, I'll be pyrolyzing/incinerating, grinding, filtering, then re-dissolving what's left. ( I never got around to incinerating anything yet, but I did process a couple things separately . ) The boards get processed seperately if there's any gold plating/traces, or if not they go to the scrapyard as "copper bearing".

About 2 years after that, I started sorting things into separate containers.

I got tired of chiseling everything off, then going through the big bucket of components looking for certain things.

So after I finish up with the small pile of boards I have left, now I'm just going to cherry pick certain things and take what's left of the boards to the scrapyard as low grade. Which is what I should have been doing from the begining.

Edit - reworded
 
I am still a newbie but have been meticulously stripping boards and saving jars or buckets of components etc. One thing I do is have a container for gold plated board materials that need solder shields removed, so I can later process a batch in hot lye and water before adding to another pile for AP processing. It seems I get pretty much gold from these kinds of boards, which include some cell phones, lap top finger sensor pads, high quality gold plated boards, and whatever else I come across.
Other bins include:
1 MLCCS
2 tantalum caps
3 RAM boards
4 IC chips
5 CPUS
6 copper containing transformers and motors
7 DVD and CDR components (laser eyes, arms, etc)
8 Aluminum parts
9 plastic junk for free disposal at the local dump recycling yard
10 Metal parts to take to the local scrap yard
11 Items for use in craft projects (ie. resistors, hard drive parts, gears, motor parts)
12 screws
13 other copper containing parts
14 wires for the scrap yard
15 copper containing wires for later stripping
16 HIgher quality IC chips (that contain gold bonding wires)
17 Pins and any other metal electroplated pieces
18 old switches for re use on projects
19 Vintage caps and other electronic components for re sale mostly
20 stripped boards
....and a few things I'll probably end up tossing out because they really aren't worth anything.

I think that's about it. :mrgreen:
 
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