Charcoal

[Kellep]

Hey guys, I've been lurking for a while and now I am finally making my first post

I have some "fingers", that's what you call the gold on the board connectors right?

Could I heat the boards in the absence of oxygen (much like making charcoal) instead of using one of the others processes?

Open burning is forbidden right? But maybe this isn't, this would not burn the board, just turn it into charcoal, gases would be burned immediately after being released and the process of recovering the metal should be easier and safer, no chemicals in the primary phase.

What do you think?

 

[4metals]

Circuit boards are often incinerated to burn off the volatile plastics. The key piece of pollution control equipment is an afterburner. Smoke is re-burned in an afterburner to completely combust any of the incompletely burnt smoke. If your afterburner is operating with a very lean flame, there isn't enough oxygen to combust the unburnt smoke and a nasty plume results. So in essence it's an excess of oxygen that allows the complete combustion of the smoke, not a lack of oxygen.

By the way, welcome to the forum.

 

[Kellep]

Thanks for the quick and helpful reply

So, do you think that if I had a small can with a hole on top with a tube connecting to the flame below I would effectively do this without any problem?

If I ever do this it will be in very small quantities so it should be easy to see if something was not working the way I wanted right?

 

[Barren Realms 007]

Thanks for the quick and helpful reply

So, do you think that if I had a small can with a hole on top with a tube connecting to the flame below I would effectively do this without any problem?

If I ever do this it will be in very small quantities so it should be easy to see if something was not working the way I wanted right?

There is a good possability of that working.

 

[jimdoc]

Fingers are the easiest thing to process. You should study the forum to see how easy it is. Especially for small amounts I think you will be creating too much work, and smoke.

Jim

 

[Kellep]

I understand what you are saying, however, I am thinking of building this for making charcoal so it I thought I could use it for this too.

Do you think it wouldn't work? I really don't know...

I've read about using sand with an electric stove to remove depopulate boards so another thing is that I could use the same setup to remove solder from the boards, it should be hot enough for solder to melt and still keep other metals solid.

 

[jimdoc]

The most popular methods on the forum are generally the easiest, and safest. Doing whole boards is messy and you must deal with a lot of wastes.

If you are going to do just the easiest stuff, like fingers, and then maybe pins and processors. Then you can sell the boards and not deal with all the wastes from whole boards. That is how I would suggest, at least to start out.

Jim

 

[Kellep]

Hm maybe you are right.

Problem is, now I have to find something I'ne never heard of in Portugal, people actually giving money for those boards :S

 

[4metals]

The thing about an afterburner is it requires a retention time, 1 second is usually enough, and a high temperature oxidizing flame. (like 1000 C)

I've seen a stack section which is essentially a long tall gas melting furnace function as an afterburner. The stack has to be long enough and fat enough so the CFM of exhaust gasses to be re-burned will remain in contact with the hot oxygen rich heat for 1 second to re-burn.

It is a lot of work for fingers but worth considering for burning boards if you can balance the feed with the afterburn retention time.

 

[Kellep]

ouch 1 second at 1000ºc seems quite hard :S maybe this really isn't the project for me. thanks