Non-Chemical Smelting in India

[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/section4/diy-shaker%20table.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,

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 .

 

[ashir]

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 .

i recently prepare an oil burner, actually a waste vhicle oil burner. it works fine. i will search for coal fired pit furnance,
one of my colleguee is machanical engineer, he was intrested to make an rotary furnance,
we were in trouble to get idea inside the furnance. if you can explain then may be we can get idea to prepare furnance, may be we not succeed but we want try! or you can post pics whenever you replace the crucible so i can get an idea, thanks alot

 

[ashir]

can i use clcium fuoride ( white crystals) instead of fluorspar in smelting?

 

[ashir]

what if smelt ashes with copper as collecter and then remelt the poured metals with potasium nitrate and flux to oxidise copper, then treat with hno3 then with aqua regia?

 

[gaurav_347]

Ashir,

Yes you can use copper as a collector metal. You don't need to do oxidise the copper . Just remelt this dore to make shots of copper . Treat this with nitric acid . Now you will use a lot of a nitric acid to dissolve this copper which will result in you creating a lot of acid waste. Try to find companies who are ready to buy this copper dore . They will pay you 90-95% values after the assay .. This way you stay away from chemicals. From what I have heard there are lot of chinese companies in Pakistan who are already buying these dore bars from local unauthorized E-waste refiners .


If you plan to recover these values then by yourself then cupellation is the way to go. You will end up using very less acids. . Plenty of books available on this forum to study this topic. You can perform large scale cupellation .Look for videos on youtube by owltech to understand the concept and study the books provided here on the forum to understand what is happening and how it should be done safely . Stick to what is being done already and do it in a much better way with safety of yourself and the people around being the priority.

 

[ashir]

thanks gaurave!
chinese companies start to buy dores in early 2005
and later on they completely hold the refining process, no one can sell now such material because refining is banned in pakistan now, and if some one try this then he have to go to jail!
even buying scrap is also now a troubke here, chinese companies are picking everything
cupelation mus need to use lead as collecter and its the only one collectr metal i want avoid !
so copper or silver are intresting!
well i was thinking to request you one more thing
can you post some pictures of your pit furnance?

 

[ashir]

Ashir,

Yes you can use copper as a collector metal. You don't need to do oxidise the copper . Just remelt this dore to make shots of copper . Treat this with nitric acid . Now you will use a lot of a nitric acid to dissolve this copper which will result in you creating a lot of acid waste. Try to find companies who are ready to buy this copper dore . They will pay you 90-95% values after the assay .. This way you stay away from chemicals. From what I have heard there are lot of chinese companies in Pakistan who are already buying these dore bars from local unauthorized E-waste refiners .


If you plan to recover these values then by yourself then cupellation is the way to go. You will end up using very less acids. . Plenty of books available on this forum to study this topic. You can perform large scale cupellation .Look for videos on youtube by owltech to understand the concept and study the books provided here on the forum to understand what is happening and how it should be done safely . Stick to what is being done already and do it in a much better way with safety of yourself and the people around being the priority.

setting up a furnance, soon i will post pics, will need your guide

 

[ashir]

i mannually depopulate 30 kg cell phone bords(old) no chinese boards.
today i pyrolise 4 lb ics, 3.4 lb mixed pins, cameras, 4.9 lb mlccs.


after pyloising, crushed in mortrar and pestal( i have ball mill but its not working fine, some pully issues)

i find that, in crushing, there is still alot carbon under pyrolised layers of ic chips!

should i repyrolise ash or go agead as it is,

 

[kjavanb123]

Ashir

Nice job on pyrolysis. If you have chosen to go lead smelting path, this pyrolysis is enough, just crush them as much as you can mix them with flux and ratio given to you by kurtak and smelt.

Best regards
KJ

 

[ashir]

thanks kj,, i choose smelting with lead, i am crushing them as fine as i can do with mortrar,
heavy rains cause to stop the smelting process. as rain stop , i will give a try to smelt a half kg ash at first, i will post my results

 

[kjavanb123]

Ashir,

Hope all is going well with your smelting. Currently I am smelting a batch of ICs using lead oxide, here are some photos and numbers I liket to share with you and everyone else.

ICs net weight: 530 grams
IC ashes (after pyrolysis) : 437 grams

Flux weight: 2 x 437 = 874 grams
Lead oxide weight: 30% x (437 + 874) = 420 grams

Flux break down as following;
Soda ash (50%) of 874 grams = 437 grams
Borax (40%) of 874 grams = 350 grams
Silica (10%) of 874 grams = 87 grams

For silica source I just crushed a broken glass.

All the ingredients were mixed well, obviously it created much larger volume, and since I have only a 2-kg graphite crucible in hand, I have to pour and smelt in smaller batches.

Here is photo of pyrolyzed ICs


Here is what they look like after crushing.


This is the mix of flux lead oxide and crushed ICs ready for the smelting.


I smelted few cups of above mixture as my crucible size only 2 kg copper, after pouring the slag looks glassy and only few big metallic beads were noticed in the slag, and metallic fraction seems fragile, so I am going to remelt this batch using more flux to see if metal collection improves.

Here is a photo of slag and metallic beads


Keep you all posted soon.


Best regards
KJ

 

[kjavanb123]

Ashir

I noticed that I had to add extra 200 grams of that flux specially soda ash as pour wasn't as fluid as I wanted.

It seems to be much better now.

After smelting the IC ashes completed I was left with a 740 grams of lead dore, as in this photo,


Here is the remains from cupelation, mostly copper plus gold.


This is the copper dore after hammering it to remove oxides and cement. They weighs 33 grams.


And finally the copper nitrate solution from dissolving copper dore in warm dilute nitric acid. There are some what seems tin nitrate forming at the bottom and gold which showed up almost near the end of copper and tin dissolution which form a brown layer on top.


Best