# Scrubber for smelting



## kjavanb123 (Oct 15, 2013)

All,

If one wants to use pyrometallurgy to smelt circuit boards, can fumes be filtered first then directed by a pipe into a bucket filled 2/3 by water, then exit from another pipe out of the bucket? 

Thanks and regards,
Kevin


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## butcher (Oct 16, 2013)

My thought on the subject.

Burning the smoke (incomplete combustion) with an after burner would be the best way to lower the toxic fumes.

Bag filters can catch some of the larger particles, but the tighter the filter the harder it would be to keep enough draft in the burners (fans and large filter surface area and exhaust piping will help some), bubbling the gases through water would help a minor amount, for some of the toxins, but most of the smoke and toxins would just bubble through the water so fast most of it would pass on through.

A good afterburner would be the most important to complete combustion, (or recycling the flue gases back to the combustion chamber to re-burn), bag filters, bubbling through the water or a base solution Could help somewhat for some of the toxins that would produce acids.


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## kjavanb123 (Oct 16, 2013)

Thanks butcher, you know a good company that makes filteration system you discussed? Itliainfo ?

Regards,
Kevin


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## bswartzwelder (Oct 16, 2013)

NoIdea AKA Deano has built incineration units whereby the exhaust gasses are redirected into the combustion chamber. He states that once the unit gets hot enough, the gasses being redirected into the combustion chamber burn well enough that he can turn off the fuel supply to the combustion chamber. He needs to turn the fuel back on as the items being incinerated stop producing fumes on their own. I hope this may help.

Sorry, but somehow, this message got double posted. I deleted the other copy of it. I have been experiencing no home phone for the last 2 weeks and sketchy DSL service from Verizon. Both, the phone service and DSL come to the house on the same line. They are supposed to be out again this afternoon to fix it.

Bert


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## goldsilverpro (Oct 16, 2013)

A guy I knew in Oregon incinerated x-ray film scrap. He put the exhaust smoke through a series of drums filled with water. In just a few days, everything solidified. The drums were filled with solid stinking gunk and everything stopped. I think the same would happen with boards. Like Butcher said, you need an afterburner, at least. Depending on the efficiency of the afterburner, you might also need a baghouse. They are quite expensive. In the late 60's, a very large refinery I worked for spent about $250,000 - $500,000 on a baghouse. 

I can't see you being able to smelt those boards directly without incinerating first. The standard method is: Incineration; Ball milling to powder the ash; Screening at 10-12 mesh; Melting the metals that are on top of the screen into bars (called refiner's bars); Sampling and assaying the bars and the ash (called pulps) that went through the screen; Shipping both bars and pulps to a primary copper smelter for processing.

I did know of a guy in the desert in New Mexico that was processing refiner's bars using about 10% sulfuric in a large membrane cell.


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## kjavanb123 (Oct 16, 2013)

Goldsilverpro,

Thanks for your post, I think I did the steps you mention, incenaration, ball mill and remelt the metallic pieces into an alloy piece, which you can see at the following, I also kept the pulp, both are sent to a lab for fire assay for gold and ICP mass for other elements analysis, all the melting was done using an induction furnace which worked pretty fast on boards, but created a hell of smoke, the only thing that needs to be solved is dealing with smoke, I guess I couldnt redirect the smokes into the graphite crucible inside the coil of induction? Is this a closed loop system?

Refiner s bar



Pulp







Thanks and regards,
Kevin


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## kjavanb123 (Oct 21, 2013)

All,

The ICP result for my alloy metal is ready, Cu is 58%, Zn at 38%, and gold is not ready yet. This was from few pieces pf gold finger cards. 
I tried the following scheme trying to burn the toxic fumes coming out of smelting boards, to inert it through water then through a bucket filled with hot charcoal. Please advise.






Regards
Kj


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## butcher (Oct 21, 2013)

Just from what I can see in the pictures, paper is unburnt on the outside of those thin tin cans, this tells me anything inside those cans is also unburnt, or not completely combusted, Note at the temperatures you need those cans would be red hot, if not up to the point of melting, and with these acidic gases that thin steel can would not last long.

The Idea is sound, but you need better equipment and much higher temperatures.


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## kjavanb123 (Oct 21, 2013)

Butcher,

Thanks for your post. This was just small test set up. I will prepare a set up using the right components.

Regards,
Kevin


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