Pyro at its best

[bswartzwelder]

I see no reason why the gasses shouldn't burn. Keep in mind however, gasses do have an upper and lower explosive limit. Too little gas and there isn't enough for an explosion. Too much gas and there isn't enough room for oxygen to support an explosion. Having said that, you get gas and air in the right mixture and you could have problems. With a system of this type, there is an open flame (or a lot of hot embers) available all the time. When the chips start to off gas, there isn't enough for an explosion, but it will add to the combustion. As the gasses increase in volume, there is sufficient volume of gasses to keep the fire going without an external combustion source. As Deano said, once the chips have delivered all the combustible gasses there is, the fire starts to go out. Roar, then no roar, then roar again.

 

[kurtak]

Personally this was the best investment I ever made :arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=40&t=22581&hilit=incinerate#p237094

one piece of equipment used for incineration - or - smelting - or - melting (three jobs one piece of equipment)

when incinerating there is no need for an afterburner or a loop to recirculate the unburned volatiles for re-burning --- due to the cyclonic action of the flame in the furnace the volatiles get complete combustion in the furnace right out the gate

Also no need to worry about explosions due to gasses building up - they don't have time & it breaths & the incineration takes place fast - very fast

Kurt

 

[Finn from Ecuador]

I was thinking that if the tube from sealed IC container would be the main line entering the fire chamber and the blower line connected to it in 11 degrees angle we would have an eductor. That would create easily -500mbar negative pressure in the IC container. That would mean lower oxygen part pressure and something like 11,5 % oxygen in the IC container.

As far as i understand, low oxygen enviroment is good for pyrolysis. Or maybe it brings no significant benefits in this application?

Salud

Finn

This just doesn't want to leave me in peace.

Maybe one could also add an air inlet line with shut off valve to the lower part of the IC container. The line should go through the fire chamber so that the fresh air would get pre heated.
Then when the pyrolysis is done, one could open the fresh air valve slightly and let the eductor suck the pre heated air in for to burn carbon.

OK, one more

When the burning is done, then shake the IC container vigorously by touching it for example with hammer drill for to stratify the content so that heavies drop to the bottom. Then open the fresh air valve a little bit more and let the eductor suck out major part of the fly ash. Carefully for not suck out values.

One small detail

There should be pocket at the bottom corner of the IC container where heavies can drop during the shaking. The hammer drill should touch that same pocket corner so that the stroke goes to the upper opposite corner direction and heavies would walk nicely to the pocket. Fresh air holes should be so that they won't blow the pocket during the ash removal.

This should result almost ash free concentrate i think.

 

[4metals]

Could you add a drawing or pics for your wood pellet fired design? I use a pellet stove to heat my shop and have a ton ready for this winter. I can spare some for chip burning and have about 100 pounds or so to incinerate.

I had to figure out how to use an old gas melter which held a #20 crucible to use for pyrolysis. Actually that is quite easy, just invert a bigger crucible or an old crucible liner over the crucible with the IC's in it and it forces the uncombusted material out the bottom into the flame of the melter. That looks like this;

View attachment dual crucible in gas melter.pdf

This does 2 things that Kurt's furnace does not, 1 it covers the IC's and eliminates any oxygen for complete pyrolysis, and 2, it lets the fumes out lower in the furnace to give the volatile fumes more time in the flame path to burn completely. Kurt's furnace may burn IC's beautifully, and the pictures show it does, but in reality there are volatiles escaping but in the wide open spaces where he does this it is not as noticeable. In a closed area inside a hood it would be noticed. The longer the contact time with the flames makes for more complete combustion.

The unit I set up was in a city where the buildings have long ago had their natural gas shut off. So here was this gas burner with no fuel. They were able to use a small propane bottle and they threw a scoop of pellets in the bottom of the furnace. The initial propane lit the pellets and once lit they provided the heat required to get the pyrolysis going. He was burning jewelers sweeps and had to work out the amount of pellets he needed but once he did that it has been consistent. The pyrolyzed material needs to have the carbon burned off and that is done by removing the cover over the crucible and heating it after the pyrolysis is complete. He does that with pellets too.

 

[kurtak]

Could you add a drawing or pics for your wood pellet fired design? I use a pellet stove to heat my shop and have a ton ready for this winter. I can spare some for chip burning and have about 100 pounds or so to incinerate.

I had to figure out how to use an old gas melter which held a #20 crucible to use for pyrolysis. Actually that is quite easy, just invert a bigger crucible or an old crucible liner over the crucible with the IC's in it and it forces the uncombusted material out the bottom into the flame of the melter. That looks like this;



This does 2 things that Kurt's furnace does not, 1 it covers the IC's and eliminates any oxygen for complete pyrolysis, and 2, it lets the fumes out lower in the furnace to give the volatile fumes more time in the flame path to burn completely. Kurt's furnace may burn IC's beautifully, and the pictures show it does, but in reality there are volatiles escaping but in the wide open spaces where he does this it is not as noticeable. In a closed area inside a hood it would be noticed. The longer the contact time with the flames makes for more complete combustion.

4metals - thanks for posting this - I will have to give it a try because I want to build a room inside the barn I work out of so I can continue to work my incineration, smelting & melting operation during the winter - as it is now I have to shut that part of my operation down during the winter as its just to cold outside to do it

I have the blower & ducting for the indoor fume control but need to get the sheet metal to build the walls & ceiling of the room as well as cement board for the floor - I should have the funds for those building materials this coming January so hopefully I can still have it up & working before this winter is over

Kurt