Smelting in India

[kurtak]

i have no idea on concentrate the ashes ! what will be the best way to wash off ashes without loosing pm's

ashir

There are a number of different ways to concentrate your chip ash

Examples - panning with a gold pan - using a blue bowl - sluice box/miller table - shaker table - I have even used 5 gallon (20 liter) buckets

Regardless of the method you use what is important is learning how to do it "without" washing off some of the gold bonding wires when washing the ash off because when washing the ash off you can wash some of the gold off with the ash if not done right

Also the method you choose depends somewhat on the amount of ash you are trying to concentrate - AND - how often you intend to do it

You said you have about 30 kg of chips to process - that's a lot of ash to try to concentrate


So my question is --- how often do you plan to process batches of (plus/minus) 30 kg of chips


Kurt

[kurtak]

One more question --- can you provide some pictures of the chips you are wanting to process ?

Kurt

[ashir]

One more question --- can you provide some pictures of the chips you are wanting to process ?

Kurt

at the moment i am fr from my work area, (for some scrap deals)
here are few pics of mobile boards that were depopulated

image.jpg

image.jpg

and 2+ kg BGA chips.
i want use silver as collector and smelting 2 kg ash at a time,
also trying to make a tilting furnance to handel 10 kg ash at once. i am afraid of loosing values during concentration. i also watches some video and read post about concentration, and i never like this idea untill you mention it, but still i am not prepare to use such mathods where human error works as big error!

[ashir]

hi every one. can some one link me to a post to get help for making a tilting furnance.
and i dont remember if i post this already , what will be other thining flux out of fluorspar?

[ashir]

One more question --- can you provide some pictures of the chips you are wanting to process ?

Kurt

here are pic of ic's that i want process

image.jpg

and i got a gold pan , recieved today

image.jpg

[kurtak]

ashir


Sorry I have not posted more lately - I have been gone on a trip & just got back & as well I am currently sick


Could you provide a better picture of the chips --- I would like to see "more" of what is in the mix of the chips

A few chips in your hand (with the rest in the back ground) does not really tell me much


Kurt

[ashir]

ashir


Sorry I have not posted more lately - I have been gone on a trip & just got back & as well I am currently sick


Could you provide a better picture of the chips --- I would like to see "more" of what is in the mix of the chips

A few chips in your hand (with the rest in the back ground) does not really tell me much


Kurt

i am far from my work area today,
i ask my worker to send me fotos but he is not understanding. though he send me this

image.jpg

i clean mobile boards(ic chips from mobiles) BGA chips from p3 / laptop mother boards. ic chips from p2 motherboards.ic chips from rams. guys are working still, collecting more ic's
untill i start smelting, so looking for your more guide

[kjavanb123]

Ashir

Once you completed the pyrolysis followed by incinerationn of IC chips. You need to use a mill to pulverize them.

They should be as fine as flour. Now this is a method I got from the YT ,link as following;

https://youtu.be/Z47ZEyD5zSE

So once you pulverized the ICs, you sift them through a kitchen sifter. Save the oversized for later.

For fine powder, add water to cover them plus maybe 5 cm above them. Add sodium hydroxide (lye-caustic soda) and use a spoon mix them well.

Let it settle, then pour off the black solution a little, keep adding lye, mix and pour off small amount until it is clearer.

Now you need to add enough lye to make it concentrated lye solution, it makes the pot to heat up and dissolve aluminum or any tin in the mix plus it dissolves silica in the ash.

You let this on low heat for an hour, then slowly add water to it and pour off a little, repat till solution is clear.

This safely concentrate your ash to smaller volume.

Best of luck
KJ

[ashir]

thanjs kj!
hope i can do this,

[kjavanb123]

thanjs kj!
hope i can do this,

Sure you can. Please note sodium hydroxide reacts with glass or aluminum pots so use stainless steel container to do your lye processing.

Also always wear glasses and protective gear hot lye solution is more dangerous than sulfuric acid.

[ashir]

thanks kj to remind ne about safety. i will di it under proper safety! thanks alot!

[ashir]

kj i read more on what you mention! loosing gold is the mainissue! i am still too afraid of loosing values as gold wires sometimes broken so fine! i still want use smelting mathods as i am also finding ores to be processed! big batches of e waste !
chamicals and labour is still too cheap here. 3 to 7 dollars per 10 hours is labour cast here!
though its hard to find chamicals but these are all cheaps ( out of flourspar) ! the mathod you mention is quite intresting and safe as low waste production!
but i have to run 2 different setups for ewaste and ores! so i was intrested in one in all( hope you understand what i want to say because my english ability is not so good)
but in smelting i am not feeling good to use lead( as it will raise same issue of too much toxic waste)
so i was looking to use silver as collector, copper is a choice if shark start a thread of coper cell( he once ask that soon he is going to do so)

[ashir]

one more thing
i am looking at kurtak
at same time thinking to process ic's with connecter pins( from mibiles) mlccs combine.
question raise
why process 10 kg,while ashes can be reduced by 5 kg
but
leaching pins require one extra setup, ( iodine is expensive, cyanide is banned, Ap deal with chlorine )
why not combine whole and process with flux! ?
collect clean mobile circuit boards and later smelt them and run in copper cell to get copper and any gold in plating!

[kjavanb123]

kj i read more on what you mention! loosing gold is the mainissue! i am still too afraid of loosing values as gold wires sometimes broken so fine! i still want use smelting mathods as i am also finding ores to be processed! big batches of e waste !
chamicals and labour is still too cheap here. 3 to 7 dollars per 10 hours is labour cast here!
though its hard to find chamicals but these are all cheaps ( out of flourspar) ! the mathod you mention is quite intresting and safe as low waste production!
but i have to run 2 different setups for ewaste and ores! so i was intrested in one in all( hope you understand what i want to say because my english ability is not so good)
but in smelting i am not feeling good to use lead( as it will raise same issue of too much toxic waste)
so i was looking to use silver as collector, copper is a choice if shark start a thread of coper cell( he once ask that soon he is going to do so)

Ashir

You can follow lye method to concentrate ashes to smaller volume, then follow by AR leaching.

Or

You can smelt using silver as collector, that way if your setup is right you can reuse that silver many times.

For flux you can use a stock flux (5 parts soda ash, 4 parts borax, 1 part silica).

Your best method to use silver as collector is to dissolve your silver in nitric acid, precipitate as silver chloride, then convert that use sulfuric acid and cement it to metallic silver which is in form of fine powder.

Now you can mix the IC ash with silver powder and flux and smelt it.

For few kg of IC ashes a regular small furnace should do the job, for larger batches best is to use a rotary furnace.

[ashir]

thanks kj.
i am working on rotary furnance. crucibles are ready so i am finding some stuff to fix crucibles in rotary furnance setup, i ask gaurave to start a thread on making of rotary furnance at home and a coal fired furnance( if he have time for us)
i want see gaurave because he is in me neighbour country and i can easily get what he will use!
also searching a fume controle idea that i can construct by myself to controle smelting fumes.
i already arranged flux
borax
soda ash
flourspar
kno3 ( its banned, no idea yet to use it but i buy it because may be next time i can not buy )
silica is not yet in my flux but i will get this soon.
what should be the ration of silver to ash
or silver ratio to axpected values?

[kjavanb123]

thanks kj.
i am working on rotary furnance. crucibles are ready so i am finding some stuff to fix crucibles in rotary furnance setup, i ask gaurave to start a thread on making of rotary furnance at home and a coal fired furnance( if he have time for us)
i want see gaurave because he is in me neighbour country and i can easily get what he will use!
also searching a fume controle idea that i can construct by myself to controle smelting fumes.
i already arranged flux
borax
soda ash
flourspar
kno3 ( its banned, no idea yet to use it but i buy it because may be next time i can not buy )
silica is not yet in my flux but i will get this soon.
what should be the ration of silver to ash
or silver ratio to axpected values?

Ashir

You do not need KNO3 for smelting. Gaurav knows me as we discussed a lot of smelting issues before.

Rotary furnace is difficult to built in home, so you maybe better of using a regular non-rotary furnace.

Please view the following link as how to setup a good size furnace,
https://youtu.be/y2RYYBRFu1A

This shows how to build a venturi burner for the furnace, he also shows how to build a furnace and use coal as the heat source.
https://youtu.be/eO8NwseRxSA

Amount of silver is related to your amount of concentrate. I think 200g of fine silver powder for 5 kg of ash should be sufficent to do the collection.

Always run a small test to get idea.

[ashir]

thanks kj. yes rotarg furnance is difficult to prepare at home, but once i will try. and after smeltinv with silver, there is no need of any cupelation! or 2 step smelting is required?

[kjavanb123]

thanks kj. yes rotarg furnance is difficult to prepare at home, but once i will try. and after smeltinv with silver, there is no need of any cupelation! or 2 step smelting is required?

What I do here is to use lead oxide as collector, smelt everything, skim off slag, then oxdize the lead into lead oxide and all of the base metals presented in lead will be skimmed off.
Near the end silver is added and remaining lead is oxidized and skimmed off till only silver is left.

You can either run your silver dore in a silver parting cell, if I recall kadriver has a great threat about silver cell using stainless steel bowl.

Then collect the slimes, dissolve in HCL, the AR to dissolve gold.

Or

You can scorify the silver dore, add volume wise 1:1:1 soda ash, borax and glass to molten silver to remove the base metals, you need a steel pipe connected to an air compressor to slowly blow air into molten silver this oxdizes base metals and they form a darker donut shaped layer on top of molten silver, just add that flux and pour, repat till bubbling air in silver doesn't produce any dark layer.

At this stage molten silver looks like mirror, this is silver without any tin or copper, you can dissolve in nitric, collect the residue and dissolve in AR.

Or lastly

You dissolve your silver dore in warm nitric acid, this results in silver/copper nitrate solution and gold with tin nitrate (metastanat acid) form at the bottom of your beaker.

Decant the solution, wash the gray residue with hot water let it settle decant do this 3 times, add lye to gray residue it reacts solution turns black add water decant, you should see your gold powder at the bottom.

Silver/copper nitrate solution, you add salt till the silver chloride is fomed, filter it and keep adding hot water till the solution coming out of filter is clear and no more blue.

And again do this on a small scale test to get the feeling.

Best of luck
KJ

[ashir]

thanks kj
i need some more clearification please.
what will the way to skimm off lead while melting the ashes? a rod with bended end will work? or i have to melt , then turn iff furnance remove sold lead with base metal and an other melt with silver?
thanks again for guide

[kjavanb123]

thanks kj
i need some more clearification please.
what will the way to skimm off lead while melting the ashes? a rod with bended end will work? or i have to melt , then turn iff furnance remove sold lead with base metal and an other melt with silver?
thanks again for guide

Ashir

If you watch my video from 1:34 onward show our process of oxidizing lead dore to remove impurities.

In order to do that you need to build a sinilar furnace. Guarav at some point was given the design schematics so maybe you can ask him.

For regular furnace like the ones in the YT channel provided in my previous post, you need to watch a video by owlTek, a memeber of tjis forum, here is his video link.

https://youtu.be/hyDlrVgJETw

And for the first step of lead smelting please watch CodyLab YT channel below as he does something similar. Notice his cupel is manufactured but owlTek cupel is homemade by portland cement.

Part 1
https://youtu.be/OyOzfP-JAI4

Part 2
https://youtu.be/Qo32s7zrCP0

Here is another cool video shows how lead smelting followed by cupelation is done in South Asian countries,
https://youtu.be/5TQmEq5A4Mo

[ashir]

very informative
i will watch them carefully and i will ask if i cannot understand any steps
thanks alot

[kurtak]

ashir

First - sorry I have not posted more - just been to busy

Kevin

you posted -----

Amount of silver is related to your amount of concentrate. I think 200g of fine silver powder for 5 kg of ash should be sufficent to do the collection.

200 g of silver for 5 kg ash is not even close to enough silver to get good collection of metal in a smelt


using such a VERY small amount of collector metal in a smelt WILL result in "small" beads of metal "hanging up" in the slag --- which mean "loss" of metal in the slag

There NEEDS to be enough metal in the "smelt load" for "all" the metal to come together when the load becomes molten

The smelt load - is the total weight of all component's going into the furnace

The components of your load are --- the ash being smelted - plus - the flux - plus - the collector metal

To "insure" that you get "complete" collection of the metal in the smelt you want the load to be "at least" 30% metal

That means for every kg (1,000 grams) in the load - 300 grams needs to be silver (your collector)

Your ratio of flux to ash needs to be 2 parts flux to 1 part ash

So here is an example of a kg smelt load ----------

233.333 grams ash - plus - 466.666 grams flux - plus - 300 grams collector metal (silver) equals 1,000 grams smelt load

This is why you "need" to concentrate the ash as much as possible --- if you don't concentrate the ash - you will need to use a HUGE amount of collector (silver) & "many" smelt loads - to collect a SMALL amount of gold

Kurt

[ashir]

thanks kurtak.
i understand the logic of concentrating ashes.
i am nealy ready to do some small experiments as kj said
i also got some lead oxide, silver and going to do some experiments with both as collector
i will post my results and the procedure
i am also busy in making a desi type rotary furnance.

concentration via gold pan is a good idea?

[kernels]

concentration via gold pan is a good idea?

No, it is almost impossible to pan bond wires from ash without losing quite a lot of them, they are often long and bent/coiled, so they do not settle in a pan the same way that alluvial Gold does.

I have had good results with bucket washing and blue-bowl and medium results with drainage pipe sluicing.

I would love to try a good shaker table type setup at some point.

[ashir]

concentration via gold pan is a good idea?

No, it is almost impossible to pan bond wires from ash without losing quite a lot of them, they are often long and bent/coiled, so they do not settle in a pan the same way that alluvial Gold does.

I have had good results with bucket washing and blue-bowl and medium results with drainage pipe sluicing.

I would love to try a good shaker table type setup at some point.

the problem i am facing is to find the "any prepared setup."
can you suggest some videos or documents or a post to setup a shaker tables at home!

[kjavanb123]

concentration via gold pan is a good idea?

No, it is almost impossible to pan bond wires from ash without losing quite a lot of them, they are often long and bent/coiled, so they do not settle in a pan the same way that alluvial Gold does.

I have had good results with bucket washing and blue-bowl and medium results with drainage pipe sluicing.

I would love to try a good shaker table type setup at some point.

the problem i am facing is to find the "any prepared setup."
can you suggest some videos or documents or a post to setup a shaker tables at home!

Try this link for shaker table DIY.

http://www.crazycrusher.com/download/se ... 0table.pdf

[Shark]

Thanks kjavanb123, that is the best looking homemade table I have seen.

[Platdigger]

Yes, very nice.
Would be great to see one in operation.

[ashir]

gaurave ! you posted a picture of rotary furnance,

image.jpg

i am trying to construct tge same at home!
i can not find proper informations, if you kindly answer some questions!
the upper view( as shown in picture has no holes from where burning fumes get the way to go out, is there any other side hole?
crucible is fixed in furnance and can i see if the furnance is filled or tgere is place inside?

[gaurav_347]

IT's a hydraulic tilting furnace . It runs on waste oil . There is a waste oil burner with a high speed blower attached to it .. The crucibles are replaceable . You need to unscrew the top ring. The burner is attached to a oil supply drum which is kept at height . It will be hard for a newbie to operate such kind of a furnace. I would strongly suggest that you build a coal furnace out of a oil drum or a pit furnace . You cannot use regular coal but instead you have to use net coke . It gives temperatures which could easily melt iron . In Fact we started using pit furnaces more than oil fired or gas fired furnaces at our plant. It's more convenient and we can easily do 8-10 50kg smelt loads in a day. look for coal fired pit furnaces online .