Pyrolysis reactor

[snoman701]

If insistent on paint can design, just pop a hole in the bottom and use a tight fitting tube to vent gas from inside the can near top of lid to bottom side of can near flame. Positive pressure will force an outward flow. I.e...the vapor lock is not necessary.


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[upcyclist]

If insistent on paint can design, just pop a hole in the bottom and use a tight fitting tube to vent gas from inside the can near top of lid to bottom side of can near flame. Positive pressure will force an outward flow. I.e...the vapor lock is not necessary.

Didn't someone post a similar design for a cast iron pan pyrolysis sytem? As far as pipe/vent placement, that is--a hole in the bottom, but have the tube inside extend to near the top of the chamber.

I searched around but couldn't find the reference--I can't even remember if it was a drawn diagram or a verbal description.

 

[anachronism]

4metals posted it mate.

 

[upcyclist]

4metals posted it mate.

Well, that narrows it down--it's not like he posts very often :roll: :lol:

 

[snoman701]

If insistent on paint can design, just pop a hole in the bottom and use a tight fitting tube to vent gas from inside the can near top of lid to bottom side of can near flame. Positive pressure will force an outward flow. I.e...the vapor lock is not necessary.

Didn't someone post a similar design for a cast iron pan pyrolysis sytem? As far as pipe/vent placement, that is--a hole in the bottom, but have the tube inside extend to near the top of the chamber.

I searched around but couldn't find the reference--I can't even remember if it was a drawn diagram or a verbal description.

That's cool...I wonder if it was an idea I had, or something I just don't remember reading? Life blurrs together.

 

[anachronism]

4metals posted it mate.

Well, that narrows it down--it's not like he posts very often :roll: :lol:

Ha! Fascist :lol: :lol:

 

[anachronism]

Upcyclist this is the post you're looking for mate.

"If you get one of these;

http://www.agrisupply.com/carolina-cooker-9-qt-preseasoned-dutch-oven/p/90677/

and drill a hole in the center you can tap, screw in a piece of 1/2" threaded black iron pipe sticking into the pot but short enough that you can put the lid on and it will still fit tight. This will cause the gasses to pass out the bottom where they will be burned because you are heating on one of these;

http://www.agrisupply.com/carolina-cooker-stand-and-burner/p/49469/

You have to monitor the temperature with one of these:

http://www.harborfreight.com/non-contact-infrared-thermometer-with-laser-targeting-69465.html

it measures up to 950 F so it will work.

Think of all the stuff you can pyrolyze now!!!!!!!"

 

[kurtak]

Jon

I am (fairly) sure Kevin's current paint can pyrolysis reactor is an experimental prototype in which he is trying to work out better efficiency for recovery of the gases & oils of "larger" systems he has already built (Kevin can correct me if I am wrong)

Edit to add; - if you scroll up about mid way on this page you will see one such larger system (55 gallon drum reactor) with the jug he is collecting the oils in - & a tube that is burning the gases of at the oil collection jug (so I "think he is now wanting re-use those gases at the reactor - rather then just burn them off)

So the turkey fryer burner is not the answer to his endeavor as its not going to scale up well

If you have been following what he is doing - he has been working on building a pyrolysis reactor that not only pyrolysis the CBs - but also circulates the volatile gases back to the reactor as fuel (re-burning) for the reactor - AND - as well "recovers" the oils produces from the pyrolysis

He has already done this with fair success on a larger scale - so I "think" this current paint can reactor is just an experiment to improve on all that

The thing is (at least the last I know of) after Kevin is done with the pyrolysis of his material - he is then bagging the material up & taking it to a smelter for smelting - because he is not set up for the smelting part

That is why I am suggesting he build a smelting furnace :!:

With the furnace - he can do it ALL in house :!:

Pyrolysis - incineration - smelting (using litharge - as lead collector) & cupelling (to recover PMs from lead smelt) all done with the ONE piece of equipment (the furnace)

With not a whole lot of engineering - there is no reason why a furnace (such as mine) couldn't be set up to "also" recirculate the "gases" back to the furnace as fuel for the furnace - AND - recover the oils as well during the pyrolysis stage

It would just be a matter of placing a piping system (similar to what he is already doing) over the center hole of the furnace lid - instead of a "after" burn chamber like 4metals design --- the piping system "may" need some blower assistance (very low pressures) to make it efficient in the oil/gas - recovery/use

other then that - its just a mater of running the furnace at the proper temp depending the task you are wanting it to preform (pyrolysis - incineration - smelting - cupelling)

Kurt

 

[kurtak]

Didn't someone post a similar design for a cast iron pan pyrolysis sytem?

I believe that was NoIdea (Deano) from New Zealand

:arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=38&t=16473&p=166282&hilit=pyrolysis#p166228

Kurt

 

[kjavanb123]

Kurt,

Thanks for the post. Yes I was using the paint can seen in my last post to do testing and modifications, so I can do on my large scale pyro unit.

I did some changes and I think it really improved the pyrolysis.

Will post the photos soon.

 

[patnor1011]

I suppose that litharge is being used in smelting as collector but I was wondering if one can use lead instead. I mean it is quite hard to get litharge over here. I do not plan to do any insane amounts, rather few small tests to concentrate values. Few samples of ceramic capacitors and resistors. I was thinking about incinerating them, milling to powder and then using lead as collector. After that, bone ash cupels and xray and processing resulting buttons. Is litharge absolutely necessary or can I use lead? Which one will be more suited - roofing lead sheets or lead from acid car battery?

 

[snoman701]

I suppose that litharge is being used in smelting as collector but I was wondering if one can use lead instead. I mean it is quite hard to get litharge over here. I do not plan to do any insane amounts, rather few small tests to concentrate values. Few samples of ceramic capacitors and resistors. I was thinking about incinerating them, milling to powder and then using lead as collector. After that, bone ash cupels and xray and processing resulting buttons. Is litharge absolutely necessary or can I use lead? Which one will be more suited - roofing lead sheets or lead from acid car battery?

Roofing lead sheet is nearly pure lead. Lead from a battery is a pain in the butt to get to.
Edit to add:
With that, litharge is a fluxing agent. The lead is a collector of other metallics. If you use lead, without a fluxing agent, your values are more likely to float to the top of the molten pile of lead as dross. If you use litharge, it is during the reduction of lead oxide that the metallic is "collected" with the lead through the fluxing.

Lead will work as a collector, to a certain extent, but I imagine it would be a lot more efficient to use litharge.

Wonder if it's possible to use any of the glass frit's developed for pottery as a litharge replacement in fluxes, in the presence of silver as a collector. Frit 3134 comes to mind.

 

[kernels]

I am very interested in this information too, if anyone knows it will be 4Metals. Litharge is surprisingly difficult to get hold of.

 

[snoman701]

The other thing you have to keep in mind is that litharge is a powder. In order for fusion to occur, you have to have intimate contact between the lead and the PM. That is going to be a lot more difficult in a lead boat, than it will as litharge reduces to metallic lead.

If I had some litharge, I'd offer to send you some of "Grandma's cornbread biscuit mix".

 

[kernels]

The other thing you have to keep in mind is that litharge is a powder. In order for fusion to occur, you have to have intimate contact between the lead and the PM. That is going to be a lot more difficult in a lead boat, than it will as litharge reduces to metallic lead.

If I had some litharge, I'd offer to send you some of "Grandma's cornbread biscuit mix".

I don't think it is a controlled substance or anything like that, just not very commonly used. I can buy it by the ton from chemical suppliers, just not a few kg at a time!

 

[kernels]

So, it seems pretty trivial to make Litharge, take lead and heat it to just over 600 Degrees C. The lead oxidizes and you skim the PbO from the surface. Boiling point of Pb is over 1700 Degrees C, so should be a reasonably safe process if done in a well ventilated environment ?

 

[4metals]

There is an assaying procedure that is effective in some circumstances called scorification. If you assay a high grade material like karat gold, you use lead sheet for cupellation, if you are assaying low grade you use litharge because there are a lot of material in the sample that is not precious which need to be liquefied in the flux or dissolved with the lead when the reduction is complete.

Then there is scorification, which is done in a shallow dish called a scorifier. Actually a lot of you guys who melt with torches use them as melting dishes. In the dish you put your sample, usually a metal sample with lots of copper which needs to be lowered in concentration to get a good cupellation, but a lot of metals can be oxidized by scorification while the PM's go into the lead pool. Granulated lead is used with a spoon full of borax and the lead melts and forms a pool which collects the PM's, some copper, and a lot of the undesirable metals are oxidized.

Similar to a fusion using litharge, the contents of the molten scorifier are poured into a cone mold, the slag is broken off, and the cone of lead based alloy is hammered into a cube and cupelled.

So yes lead metal is likely to work, more likely on a metallic sample as a powdered sample with a lot of non metallic ash will likely float on the surface and not have the same intimate contact with the lead and borax as it would if it were mixed with litharge and flux powders.

Another thing to keep in mind is mixing. When smelting in a rotary furnace, the rotation constantly has molten lead raining down through the pool of molten metal and flux and contacting the metallic particles that may be suspended in the flux pool.

But if I were to pick any metal for a collector it would be silver (can get expensive) or copper. Then a cell cleans up the collector metal and the slimes are holding your values.

These are the dishes used for scorification assays, appropriately called scorifying dishes.



edit to add; We should not forget the health implications of lead exposure. Word has it the use of lead plumbing caused the fall of the Roman empire. Just sayin'!

 

[g_axelsson]

I mean it is quite hard to get litharge over here.

Have you tested places that sells supplies for pottery? Litharge is used as a glaze... or at least used to.
Might have to call them, a quick look showed that there are hundreds of different glazes and many containing lead.

Göran

 

[kurtak]

I suppose that litharge is being used in smelting as collector but I was wondering if one can use lead instead.

Pat

The reason litharge (PbO/lead oxide) is used in the smelt - instead of just lead - is because the PbO acts not only as a collector for the PMs (as it is reduced to lead in the smelt) but also - the PbO acts as an oxidizer for the base metals thereby allowing the base metal (oxides) to be carried off in the slag leaving you with a PM bearing lead dore/alloy (for the most part) free of base metals

The lead dore can then be fired in a cupel - where the lead is oxidized again & the PbO is absorbed into the cupel leaving your PMs as a bead (or blob on a larger scale) in the cupel

If you use just lead as the collector "in the smelt" - it will collect not only the PMs - but the base metals as well --- so you end up with lead dore that has not only PMs - but base metals as well

That because unlike PbO - lead does not have the oxygen atom to give up to oxidize the base metal so they slag off

The problem with having base metals in the lead dore - is that they can cause gold (&/or other PMs) to go off (be lost) with the PbO & be absorbed in the cupel during the cupelling --- copper & nickel in particular (as well as tin & antimony) - in the lead dore - can cause substantial amounts of PMs going off with the PbO & absorbed in the cupel

Therefore - if you used just lead as your collector in the original smelt (instead of PbO) you would need to preform the scorification (as mentioned by 4metals) to remove (oxidize) the base metals before cupelling the lead/PM dore

Depending on the amount of base metals in the lead dore - you may have to add more lead to the scorification &/or preform the scorification several times before the lead dore is cleaned up enough to cupel it

Kurt

 

[4metals]

Depending on the amount of base metals in the lead dore - you may have to add more lead to the scorification &/or perform the scorification several times before the lead dore is cleaned up enough to cupel it

This is correct. I often used scorification on copper based bullion generated by melting the oversize metallics from incinerated circuit boards, and it was not uncommon for it to require multiple scorifications.