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While the nickel will remain it is not a game ender.

The nickel will dissolve in the copper cell electrolyte and not report to the slimes. However, since copper plates at a lower applied potential than nickel, the copper will plate out at the cathode and the nickel will accumulate in the electrolyte. So the copper you produce will be very high grade.

Soon I will start working on a thread about electrolytic copper refining.
 
Here comes the nightmare for me, and for many others I believe, even the big boys...
The Nickel build up in the electrolyte.

Any procedure known to deal with the Nickel at the smelting stage ?
 
Sure, how many million do you want to invest in a flash smelter and a pair of oxygen top blown converters and finishers?

Nickel is tolerable in the electrolyte at a concentration up to 10 times higher than Iron. The upper limit is around 20 grams per liter. It comes down to how much nickel is actually in your copper doré?

You will be running a copper electrolyte around 40 grams per liter copper and there are methods that have been in use for many years to separate the copper sulfate from the nickel sulfate but for small scale refining, the analytics may be a game breaker. Changing out the electrolyte may prove easier.
 
Here's part of an assay from 4 types of pcb that have been prepared for smelting (pyrolized and milled).
Samples are from unsieved material (fines & oversizes mixed together).
No magnetic separation done yet, it sure will be an important step to get rid of some Fe & Ni.



The Ni & Zn values seems very high.
CRT-001 has a Fe content going trough the roof and was sent for processing at a secondary copper smelter.
 
I do not understand how a representative sample was made for the analysis shown. Did you melt the metallics fraction into a bar and sample the bar?

If they were prepared for smelting and unsieved, I don't see the sample as representative.
 
I would like to Thank everyone for their input on this thread. While I am in no way ready for smelting, I am a small step closer. A very small step, as this furnace is sitting on the bottom of a 10 gallon barrel. I hope to have a small crucible by the weekend to put it to a better test. I can fire it up and bring a 4 inch x 1/2 grade 8 bolt to red/orange hot in less than 3 minutes. I ran it for an hour today with no noticeable problems. It should help to advance my understanding of using a furnace better given time to practice with it.

SANY0087.JPG
 
Thanks Dave. That chart will be handy in the future. If you look close you can see the head of a bolt sticking out on the right side of the furnace. That bright yellow looking spot inside is the end of the bolt glowing. I didn't make the furnace itself, but it has two holes so it could be fired using two propane torch's. I just made the burner, if all else fails, I will add another one just like it. I had to start someplace, and it was a lot of fun.
 
30 second video of it running in the dark, with bolt end still in place.

 
If you didn't say what that video was i would have thought you got some amazing photo's of a meteorite hurling through space!

I hope you do have, or intend to build a lid for the furnace, for that size furnace a hole in the cover about 1 1/2" will suffice. it is amazing how much heat a lid with a hole that large retains in the furnace.
 
It has a lid on it. The actual inside is 3 1/2" wide by 3 3/4" deep. The opening in the lid is 2 inch's wide. I had been thinking that the lid opening might be made a bit smaller to see if that would help retain some of the heat better. With out the lid it doesn't quite roar as loud.
 
The external dimension's are 5 1/4" wide by 4" high with out the lid. With the lid it is 6" high. I have been using a large set of pliers to remove the lid, but I would prefer a handle of some sort made into the lid. If I were to make a new one some of the things I would add would be a handle for the lid, only one opening for the burner, brazed connections instead of silver solder, and make it bigger. I am sure there will be others as I go but it is all a learning process. I would like to make one in a gallon sized can dimensions just for more true smelting type tests.

0825161406.jpg
 
OK that is a little puppy! Nice job though. See there is a definate use for a beer can for reference in photographs.

When I make cast lids I like to have a ring of metal around the perimeter. One way to do this would be to cut a metal can of the proper diameter down so it is as thick as you want the cover and cut off the end so you just have an empty "pipe" made from the walls of the can. Then get 4 screws and nuts and put one screw in every 90 degrees and put the nut on the inside to tighten it. when you look down the "pipe" you will see 4 screws stopping about an inch from center. These support the refractory so it doesn't fall out of the ring when you pour the cover. If I were making a furnace this small with walls as thin as you have made I would use a 2 inch length of black iron pipe of the same OD as the furnace body on the lid, and a longer length for the body of the furnace.

If you add extra nuts to two screws opposite each other so about 1/2" of the bolt head sticks out, you can make a bail type handle which makes removal easy. Just make sure it can swing down and not stand tall and get heated by the flame.

For the hole in a furnace that size I would use a toilet tissue tube in the form to cast the hole which should make it about one inch. And it burns out in the first heat!

Please post the details of the burner as a furnace this size could be a popular build for forum members. And which refractory cement did you use?

Nice job!
 
Burner orifice from a King Kooker cast iron burner assembly Model #WKAF2B. (I got mine at Academy Sporting Goods)
A 1/4" to 1/2" Copper reducer.
A 1 inch long piece of copper tubing.
A 6" piece of black iron pipe.
A 3/8" gas line cut off valve. Optional but I am liking it since I added one to mine.
A 8" x 3/16" steel brake line.

Using the orifice, I silver soldered the 1/4" x 1/2" copper reducer to the small end. (orifice end) The orifice is just about right to reach the wider part of the reducer without extending into the the wide area. I then silver soldered the 1 inch copper pipe into the reducer. Once done I drilled four 1/4" holes at right angles through the reducer right in front of the orifice. Take the 1/2 inch black pipe and test fit the copper tubing into it. It should be very tight, almost an exact fit. With a round file I worked the inside of the black pipe to open it up some. I worked the out side leading edge of the copper tubing only slightly, just enough to get a compression fit between it an the black pipe. Don't make it permanent just yet. I drilled a 1/4" hole 1 1/2" in front of the air holes in the copper reducer (this hole is in the black pipe). I cut both ends off the brake line and bent the last inch or so at an angle where the center line of the tubing is centered inside of the black pipe. Then I silver soldered it in place. I cut a strip from a drink can just wide enough to cover the holes in the reducer when lighting it. Once it warms up a little, I uncover the holes and turn the air compressor on.

There is one last piece, an air supply. I tried my small 2 gallon compressor but the regulator on it would not go down low enough. The next best thing I had on hand was a nebulizer. It works great, it is actually what I used in the video. When the air is turned off, the furnace runs completely silent. (I hooked the air line into the brake line.)

As for the furnace, another member, JHS, made it. He had sent it to me quite some time back but health issues had kept me from working with it. I know he has been down in health for the last few days, but maybe he can post up the mix he used for the refractory.
 
Let's see if I can word this right. If I understand correctly, the crucible needs roughly 1/4 or 25% of the crucible diameter as clearance around the crucible body when heating. This should insure better heat transfer to the material to be melted. This 25% should be measured from the top portion which should also be the widest part of the crucible. So a crucible with a 4 inch wide measurement (at the top) should have roughly a 1/2 inch clearance from the inside of the furnace all the way around. Since my furnace has a 3 1/2 inch opening the crucible should be in the neighbor hood of 3 inch's. Since 3" was unavailable from the local supplier, I went with a 2 1/2 inch diameter crucible. I could have ordered 3 1/8" graphite crucible, but went with the fused silica with a clay bond since he had these in stock. Now the real question is does all that sound about right? Also am I right in thinking that an undersized crucible would be preferred over one that was slightly to big?

Edit for clarity
 
Made a little progress today, but still have more to do before I am satisfied. After trying three different burners today, I am close. If I can melt copper, I will be happy. Here is the heat almost at it's limit earlier today and it would not quite melt copper.

Not Quite there.jpg

Late this evening I got the copper to melt, but just barely. Changed burner to the third version which helped greatly. It still needs a bit of tweaking.

SANY0093.JPG

Last test for the night.

SANY0094.JPG

Finally some little success. Poured copper from a piece of pipe and legs from IC's.

SANY0095.JPG

Still a ways to go yet, but I am happy with most of the progress so far.
 
Shark,

Take some bricks and close in the top of your furnace to to about half the size of the opening to retain more heat and it should solve part of your problem. Your hole in the top of your furnace is much larger than it needs to be and you are loosing a lot of heat from it. Once you find that this works better for you then you can have a metal plate made for it or make another top for it.
 
Yea, I agree. Use some fire clay and make a round puck a little larger than the vent hole. You can slide it across the hole until you have just the right gap. You will know because it will leave a blue flame shooting up through the gap that you may be able to see in the daylight.
 
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