Pyrolysis reactor

[kjavanb123]

Interesting, we combine all these steps, lead oxide smelting, scorification specially when we smelt mobile phone boards to get rid of copper, but instead of cupeling, we just skim off the lead oxide in a furnace which can be reused for next batches.

Our final product is silver dore with all the PMs.

 

[4metals]

smelt mobile phone boards to get rid of copper

This is an interesting statement because the one thing smelting and air sparging does not remove from the melt, other than precious metals is copper. For the most part the copper remains which makes it a viable process for producing anodes for copper refining and collecting values in the slimes.

I would guess if you added enough lead / litharge to a smelt you could put the copper into the lead alloy and drag it into the bone ash by cupellation, but that would take a lot of lead, much much more than the copper you are removing.

How are you removing copper?

 

[kjavanb123]

4metals,

You are correct, during last stage of smelting when we pull out the silver dore out of furnace, when there is copper, operator adds more lead oxide to the melt, after few minutes, turn the fuel to minimum while keeping the air at the same flow rate, this oxidize the lead mixed copper and skim it off.

Since we do not use cupel, skimmed lead pxide copper is reused over and over.

Operator can separate copper from the lead oxide once we accumlated enough.

Lead oxide without any copper is brittle and dark yellow in color, when it has copper it is mallable and dark in color.

Regards
Kj

 

[kjavanb123]

All,

After modifying my last prototype, I built the following pyrolysis system that on the first test run worked perfectly.

Here is the overall photo,


So on the right, that rocket looking chamber is my pyrolysis chamber, the cone makes the fumes come out with great speed, entire container that I put plastics materials engulfed in heat, the connecting surface between the cone and container I used heat resistance o-ring seal.

On the left side of photo, you can see 2 glass jars, that condense fumes comes out of pyrolysis chamber, and jars are connected using iron 10mm pipes, and one exit pipe that is connected to the intake of the blower.

There was some smoke coming out of the cap of the big jar which has been temporarly taking care of with tapes, but I will have to seal it using some types of o-ring sealer.

First jar decrease the pressure and velocity of fumes, while second jar condenses the fumes and excessive fumes are sucked in by the blower so they get enough oxygen and burn completely in the furnace.

Until the leakage from first jar, there was no visible smoke around the system nor there was any smell.

I am thinking a bigger jar, maybe even 3 jars in series, would control the flow rate and condensing of fumes.

Your comments as always are welcomed.

Regards
Kj

 

[anachronism]

I'm definitely no expert at this Kevin but I can see what you're trying to achieve.

Would a non return valve on the pipe where you feed the gases back into the furnace be a good idea to prevent a potential flash back in the system?

Jon

 

[snoman701]

Why is it necessary to condense the gasses at all? Why not just feed them back in to the combustion stream?

If condensation is your goal, pass the iron pipes through a water jacket, or force them to bubble through water. As it is now, you don't seem to have enough cooling action. You need an increase in surface area and a decrease in temperature. Best way to do that is going to be passing it through small diameter pipes that are cooled below ambient. Similar to the inside of a boiler.

 

[kjavanb123]

Snoman,

My objective to use those jars was to control the flow rate, and volume of smoke.

I have tested what you suggested to direct smoke to furnace and in my testing it did not work because the flow rate and volume of smoke is too much for my furnace to be able to burn and a lot of smoke would come out of furnace.

Using this condensers helped as the amount of smoke that is being sucked into the blower is very small compare to the flow rate of iron pipe into the first jar.

According to 4metals, smokes need to stay in hot temps for at least 8 seconds in order to completely burned.

Anachronism,
I had never experienced the effect you are talking.

 

[anachronism]

Anachronism,
I had never experienced the effect you are talking.

And I hope you never do Kevin. It's the same theory as a flashback arrester on an Acetylene tank. You don't want a spark going back into the combustible gasses.

It's food for thought mate, take it or leave it but since you're using plastic piping, a non return valve would be extremely cheap.

 

[kjavanb123]

Anarchronism,

The distance from the in-take and furnace is 50 cm or more, so I had never had it happend.

Ok pyrolysis completed, I just used the same chamber to do incineration without the cone cap, no smoke or smell while incineration and color of materials change from carbon black to white ash.

Here some photos,

Materials after pyrolysis completed,


Same material after incineration completed,



Materials inside the pyrolysis chamber this time without the cap on,

 

[anachronism]

Anarchronism,

The distance from the in-take and furnace is 50 cm or more, so I had never had it happend.

Just trying to be helpful Kevin. "It's never happened" doesn't cut the mustard when it goes bang. Most people don't get Acetylene flash backs but they still fit arresters. You've got the potential for the ignition to come backwards- a fan failure for example. If you can build something in to prevent if for a couple of bucks.... Well - up to you.

 

[snoman701]

Anarchronism,

The distance from the in-take and furnace is 50 cm or more, so I had never had it happend.

Just trying to be helpful Kevin. "It's never happened" doesn't cut the mustard when it goes bang. Most people don't get Acetylene flash backs but they still fit arresters. You've got the potential for the ignition to come backwards- a fan failure for example. If you can build something in to prevent if for a couple of bucks.... Well - up to you.

Kevin,

A much bigger concern is that you are feeding a flammable gas in to the low pressure zone of the blower. Basically, all that has to do is happen is to shut off the blower with flame present at your forward gas nozzle and you could very well could get a small explosion in the blower. This pressure could then push oxygen and fire back in to the glass jar, and then it could get real interesting.

Now I would ask...couldn't the same thing occur in a power outtage?

Bubbling your vaporized pyrolysis gas through water will act as a spark arrestor.

 

[anachronism]

A much bigger concern is that you are feeding a flammable gas in to the low pressure zone of the blower. Basically, all that has to do is happen is to shut off the blower with flame present at your forward gas nozzle and you could very well could get a small explosion in the blower. This pressure could then push oxygen and fire back in to the glass jar, and then it could get real interesting.

Now I would ask...couldn't the same thing occur in a power outtage?

Bubbling your vaporized pyrolysis gas through water will act as a spark arrestor.

Thanks Snoman that's pretty much where I was coming from. You worded it much better than me.

 

[autumnwillow]

From your previous setup, could the smoke be incomplete combustion?
Maybe you can lower the fuel supply a bit and rely on the pyro gas as a fuel?
Or is the smoke like ashes?
I don't think its the velocity of it being too fast.

I'm trying to build a non-polluting pyro / incineration furnace like your goal. Hope you could show some more info.

 

[kjavanb123]

Autumn,

I prefer the later design. First design shown in photo of 55-gallon barrel as was mentioned by other members flames are yellow which is a sign of incomplete combustion.

In my latest prototype instead of lighting the gray smoke, I let the in-take of blower nix it with forced air and furnace will burn it completely.

I have not tested accurately using equipments and etc to see if fumes come out of furnace, but no smoke or smell could be felt around the system.

 

[kjavanb123]

I changed the gasket between the cone shaped top and chamber with graphite with iron laminated between gasket. It works perfect no leakage at all.

I have also saved the collected oil from 4 kg of boards I have pyrolized using this prototype and once I have enough, will figure out a way to condese it further to recover fuel.

Here is the collected oil 2 batches into the pyrolysis, after 4 kg was finished the amount of oil increased so I had to empty this jar twice,


Here is a shot of cut circuit boards inside the chamber before the process begins,


After 17 minutes into pyrolysis, I let it cool for also another 20 minutes, and pyrolysis completed, you can see how copper is not oxidized,


One thing noticable, later pyrolysis gets done so much quicker than the first one.

Regards
Kj

 

[tortuga09]

Very interesting this topic.
I did not understand after the end of the first pyrolis you made a second one with the same product?

très intéressant ce sujet .
J'ai pas compris après la fin de la première pyrolyse vous en faite une deuxième avec le même produit ?

 

[kjavanb123]

Hi,

The 55-gallon barrel pyrolysis did not have the fumes going back to furnace.

This small one has 2 condensers and fumes go back to furnace to burn off.

Thanks and regards
Kj

 

[autumnwillow]

May I ask why did you move from a 55gal to a smaller one?
Pyrolysis only needs about 600degC and I think the burner you are using is sufficient enough.

 

[flyfisherman]

Hey Kevin well done a process that works for you and is fairly quick.
I would be a little concerned with the lead so I hope you have good extraction and scrubbing to remove them safely, you know what health and safety rules are like these days..

Well, this process works, but is it "fairly quick"? It looks like the whole deal takes 10-12hrs, expose the worker/s to the harmfull lead and other compounds, heat, etc. Wouldn't it be better to just pyrolize the material till it turn white, when grind it to powder, magnetically remove the legs, and concentrate the gold wires with a gold pen? After this gold laden concentrate can be treated with gold desolving chemicals, gold powder droped, washed,etc,etc. This way alot of time and money can be saved. Just my humble opinion, no intention to criticize other refiners methods.

 

[kjavanb123]

Hey Kevin well done a process that works for you and is fairly quick.
I would be a little concerned with the lead so I hope you have good extraction and scrubbing to remove them safely, you know what health and safety rules are like these days..

Well, this process works, but is it "fairly quick"? It looks like the whole deal takes 10-12hrs, expose the worker/s to the harmfull lead and other compounds, heat, etc. Wouldn't it be better to just pyrolize the material till it turn white, when grind it to powder, magnetically remove the legs, and concentrate the gold wires with a gold pen? After this gold laden concentrate can be treated with gold desolving chemicals, gold powder droped, washed,etc,etc. This way alot of time and money can be saved. Just my humble opinion, no intention to criticize other refiners methods.

Hi

It is not that easy to process the way you describe. There will be losses unless you smelt with copper and part using a copper cell.

We have bag filter and scrubber for our lead smelting process as you can see in photo below,