Non-Chemical How hot does a furnace need to be to melt the ceramic in CC?

[amosfella]

I"m working on building a blast furnace for melting and alloying steel for knifemaking, and will need about 1700C out of it to do what I want with it.... I can run it up to about 1850C if I need to...
So, the other day, I was wondering if the same blast furnace could be used to melt down stuff like gold and silver bearing e-waste, and Catalytic converters for the PM content. So, I was wondering how hot it would need to melt down the CC matrix?? I can easily melt it with oxy acetalyne...
I have a fair amount of access to E-waste, and older stuff at that, and was thinking that a 30# crucible, or 50# crucible would allow me to stuff a whole mobos in, and just let it all melt, and the plastic burn off. At that kind of heat, I don't think the Plastic will give off that many fumes...

 

[machiavelli976]

melting the ceramic honeycomb sounds a bad idea to me. difficult to recover the values after , futile complication.

 

[nickvc]

I dont know if you have what hear in the UK we call the environment agency but if you do i think they might pay you a call if you try burning off volumes of plastic or boards,the smoke will still appear and the only way to control it is with after burners , and im sure that your equivalent agency will be very interested in testing the output and even keener on fining you if you operate outside their limits for emissions.Sorry but there is no easy way with e scrap unless you have deep pockets and a constant large supply of materials to pay for the outlay.

 

[goldsilverpro]

According to this, about 1500C - 1600C = 2732F - 2912F. It is being done with plasma arc furnaces. The metals then collect at the bottom of the melt.

http://www.multimetco.com/pages/?pageID=4

"Multimetco has a patented process for reclaiming precious metals from the catalyst. The heart of the recovery operation is a plasma arc furnace. The catalyst materials are fed into the plasma arc furnace. A 10,000 degree centigrade electric flame moves across the surface of the catalyst heating them to temperatures that range from 1,500 to 1,600 degrees centigrade. The plasma arc is moved above the molten bath to distribute the tremendously intense heat over the entire surface, keeping the bath fluid and providing a stirring effect, causing the precious metals to collect together and settle to the bottom of the furnace in a layer of molten metal. The slag flows continuously form the furnace, is cooled, crushed and sold to steel manufacturers for use in manufacturing high grade steel. The precious metal alloy is tapped, cooled, milled, then refined into Platinum, Palladium and Rhodium."

 

[amosfella]

The environment agency won't be a concern for me... I live a long way from any city. A lot of the stuff I do involves fire and smoke. Blacksmithing from a coal forge, etc. Nearest neighbor is over 2 miles from me...
At 1700C, I'm pretty sure that everything will be burned in my furnace... The design also makes complete incineration more than likely...

 

[Platdigger]

At 1700C, you will vaporize mot of the pms on pc material also.

 

[qst42know]

((Unrelated to the original thread)

Being that you smith with coal already there is a question that has been nagging me.

Have you ever melted (smelted?) any copper powder cemented from your acid wastes?

I was wondering if the carbon monoxide from a coal fire alone would be enough flux to reduce the copper powder to a solid ready to sell as scrap. Primitive copper smelting was done with coal in a shaft furnace.)

 

[amosfella]

I have not tried melting copper in a coal fire. I have only added tin to make brass. But not with acid waste... Something interesting to try... The propane furnace I'm making will have a reducing atmosphere, meaning that all the oxygen inside the furnace will be burned to the point that some propane will be burned outside the furnace.... It needs to do that to smelt the steel I want to make, otherwise it will not bond with the carbon properly....
As for vaporizing the PM's from e waste, I dont' think it's likely... Sinver vaporizes at 1950C, and Gold and 2600C... Don't think it's a problem. I said the furnace could reach those temps. I didn't say that I would use them on the ewaste...

 

[4metals]

In addition to the high temps. you will need a flux to help liquefy the ceramic. The ingredient of choice for this task is cryolite, chemically called sodium hexafluoroaluminate. It is also tough on crucibles so be careful. Adding copper as a collector will also help pool the metals.

 

[qst42know]

In addition to the high temps. you will need a flux to help liquefy the ceramic. The ingredient of choice for this task is cryolite, chemically called sodium hexafluoroaluminate. It is also tough on crucibles so be careful. Adding copper as a collector will also help pool the metals.

I suppose it's no surprise a company would leave out the important bits in their process snippets. :mrgreen:

 

[amosfella]

Is the same flux used to help break down the metals also useful for breaking down the boards in ewaste?? Reason I ask is I have stumbled on a large pile of mid 90s computers and possibly servers as well...

 

[4metals]

Flux doesn't break down metals it helps them flow together. The cryolite is good for ceramics but for the plastics used in circuit boards the method of choice is incineration, high heat to burn the plastics off, followed by an afterburner to burn the un-combusted smoke. The after burner is the pollution control device.

Once the materials that can burn off are gone, the remaining metals can be collected by melting with a flux. So circuit boards are a 2 step process.

 

[amosfella]

My bad, I meant matrix, not metals... Wasn't fully awake when I typed that...
Where would one get cryolite from??

 

[4metals]

Chemical suppliers can usually order it in, it comes in 50 pound bags. Check with the guy you get Borax and Soda ash from. http://www.wegochem.com/en/products/flux-metal/126/

 

[amosfella]

I was thinking about the plasma arc furnace... I was wondering if the martix from the CC could be put into a graphite crucible, which would be attached to a ground connection on a welder, and use a carbon gouging rod from the welding side to form an arc to melt the matrix and the metals... Might create an interesting experiment at the very least... A carbon arc will produce over 3000C...
Can the carbon later be taken out of the metal (if any gets in of course) by further wet refining??

 

[4metals]

I believe granulated circuit boards are fed into a plasma arc at Aurubis (formerly the New Deutsch Refinery) in Germany. They are primarily a copper smelter but that's where all precious metals end up. Their website is http://www.aurubis.com/en/our-business/raw-materials/

If you look at the site and print out some of the pdf brochures you will find their process description.

 

[Harold_V]

I was thinking about the plasma arc furnace... I was wondering if the martix from the CC could be put into a graphite crucible, which would be attached to a ground connection on a welder, and use a carbon gouging rod from the welding side to form an arc to melt the matrix and the metals... Might create an interesting experiment at the very least... A carbon arc will produce over 3000C...
Can the carbon later be taken out of the metal (if any gets in of course) by further wet refining??

I am of the opinion that residual carbon isn't an issue.

You might find something of interest by searching Lidsay's books http://www.lindsaybks.com/ for information on building a carbon arc furnace.

Harold

 

[linden940]

if you ask me...*I made a forge* the better way to go or...it was for me...my forge ran on raw wood or charcoal an....it was not cheap lol.....no place around here would sell me coal *or from what I had found* unless I was buying a train cart load

so i sold that forge after I had it for a wile (it worked great.....but I burned alot of wood/charcoal) and I am building a waste oil burner the one I made is very simple *tested it using water and it worked so to say* but have not yet made the forge body as it will need to hold up to little over 3000F I have heard of them getting as hot to all most 4000F.....and get can get the waste oil pretty much ANYWHERE so you dont need to buy any wood charcoal or even coal....


p.s I DID worked with coal before....one thing i hated....if u had it outside in a bin...and it rained...it could be days before you can forge.....same with wood but when you buy a ton or so...it is kinda hard to keep it inside =P......oil can sit anywhere you put it inside a oil barrel waiting for you to use it....and if you look around U can find 55drum WITH the lid for free or for a few $...no big deal

 

[Oz]

I have spent a lot of hours over a forge, and while wood coal will do the job give me a low sulfur bituminous coal any day instead.

For smelting though (at least for iron) I would far prefer the wood coal. I am at a loss as to how to explain why in exacting detail, but empirically it was by far the preferred fuel in reducing the iron ore I was working with at the time.

 

[Harold_V]

For smelting though (at least for iron) I would far prefer the wood coal. I am at a loss as to how to explain why in exacting detail, but empirically it was by far the preferred fuel in reducing the iron ore I was working with at the time.

Most likely because of its low sulfur content.

Harold