OLDGUYS TRIPLE BARREL CHARCOAL RETORT DESIGN

[FrankRizzo]

No silly! I was wondering if this would be good for a willow shell? It's paulownia wood.

 

-dag

 

Dag,

 

Paulownia is too reactive for willow. A shell made with willow stars from Paulownia turns into a charcoal-orange snowball.

[oldguy]

Thanks! You have done a great job with this post! Many thanks.

 

A word of warning.

Wear gloves & a respirator when working the insulation mix. DE, Vermiculite & Perlite absorb a LOT of water.

And for sure, you don’t want to get any water glass in your eyes. I did not measure how much water I used.

But guess around 8 gallons to get a tacky workable grout.

So there was a lot of water weight.

Which if slow dried, evaporates off.

The end result being a very light weight refractory insulation.

 

Also, if I had it to do over again,

I would use 1.5 inch square steel tubing for the legs.

As it’s cheap & easy to drill holes in.

 

I would not hesitate to use all 1 inch pipe & gate valves either.

As it is FAR less expensive than 1.5 inch pipe & fittings.

Since the heat build up is slow to start, you don’t get sudden surges of pressure & flammable gas.

 

Once I had the steam heated off.

I switched the valves, closing the upper one & opening the lower one.

I adjusted the lower valve a little, closing it, then opening it.

Pressure built up fast (pinging sound) & I released it with a whooshing sound.

 

Then adjusted the lower valve until I got a nice even hissing sound.

Which maintained some amount of pressure in the upper inner drum for the duration of the cook off.

 

 

[FrankRizzo]

[quote name=oldguy' timestamp='1329843329' post='92374

This morning open upper barrel.

 

Remove inner drum lid.

 

SHOCKED……..

 

Load did not appear to have shrunk more than 5%.

 

Thought it was a FAILURE.

 

Started unloading the inner drum.

 

(stupidly, in the excitement did not take a picture before I started unloading the inner drum".

 

SHOCKED…… 100% charcoal.

 

 

 

 

These were 2X6X about 23 inches

 

Almost NO shrinkage

 

A rough guess is shrinkage was about 5 to 6%.

 

Whoot Whoot…… …… this triple drum sumbitch system works better than I could ever even imagine.

 

Wow, that is definitely a testimonial to your ingenuity, right there Do you have any idea what pressures you were maintaining in the conversion barrel? I recall a statement on this page linked in your Consistent Quality Charcoal thread about pressure achieving higher conversion efficiency by weight. It certainly looks like you've gotten close to that goal.

 

I've never cooked Paulownia before, so I suppose there may also be something in the grain geometry or lignin structure that doesn't pull the wood into a denser structure as it's cooked (like pine does).

Edited February 21, 2012 by FrankRizzo

[pyrokid]

Fine work, Oldguy!

[oldguy]

Wow, that is definitely a testimonial to your ingenuity, right there Do you have any idea what pressures you were maintaining in the conversion barrel? I recall a statement on this page linked in your Consistent Quality Charcoal thread about pressure achieving higher conversion efficiency by weight. It certainly looks like you've gotten close to that goal.

 

I've never cooked Paulownia before, so I suppose there may also be something in the grain geometry or lignin structure that doesn't pull the wood into a denser structure as it's cooked (like pine does).

 

Thanks for the kind words.

 

This was the very first burn off with a load of wood inside the upper inner drum.

The high temp thermocouples I ordered have not arrived yet.

 

So, this test was by the seat of my pants, by sound, feel & a hand held infrared thermometer gun.

 

Previously, when attempting the same thing in an autoclave.

I totally wrecked a handful of high end pressure gauges.

They don't seem to like molten lava like bubbly creosote tar.

 

So, I have nothing to gauge the internal pressure by on this either.

There must be a way, I just haven't found it yet.

 

I just used sight & sound to adjust the internal pressure in the range I was comfortable with it.

 

When the firebox was going full blast & I closed the valves.

After a moment or two, I could hear internal pressure building rapidly.

As the inner drum made a "pinging" metal stress sound.

At the same time the piping began to leak hot thick molten tar at the thread joints.

 

 

So, there was a LOT of pressure building up quickly.

 

I had previously tightened all the piping with two 14 inch pipe wrenches.

Not so hard it would give me a hernia, but darn tight.

For those pipe fittings that tight to leak shocked the hell out of me.

 

I would suggest using some of this to seal the pipe treads & joints beforehand.

 

 

I was truly mind boggled when I first opened the upper in drum.

No doubt muttering WTF several times.

I thought it was a total failure at first glance, because of the lack of shrinkage.

 

Then I picked up a piece. Again shocked, it was light at a feather.

The other shocking thing was some of the charcoal had a shiny bronze sheen appearance in places.

But only on a microscopically thin surface level.

Once broken, the inside was as black & shiny as coal tar.

I would think it would be visa versa with a brown sheen on the inside & under cooked.

 

So, it did work, just far better than I thought it would.

 

I think it is because of the slow build up of heat, relatively constant heat, in combination with pressure.

Burn off was around 4 or 5 + hours, then shutting it down to cool overnight.

Emptying the inner barrel was not messy or difficult at all.

All in all It was a clean leisurely affair about like crock pot cooking.

Edited February 21, 2012 by oldguy

[dagabu]

Dag,

 

Paulownia is too reactive for willow. A shell made with willow stars from Paulownia turns into a charcoal-orange snowball.

 

CRAP! Oh well, back to white pine.

 

-dag

[oldguy]

CRAP! Oh well, back to white pine.

-dag

 

PM sent......

[allrocketspsl]

Oldguy,you have made a master piece and Im glad it turned out but hey with all the correct moves you made truly you knew it would work and Im sure now glad it worked better than you thought.Pipe thread plummers use might be good to use.I have no idea which one.great job I shall take a pound of your best pine you have? Just kidding!Ten stars!!

[oldguy]

Oldguy,you have made a master piece and Im glad it turned out but hey with all the correct moves you made truly you knew it would work and Im sure now glad it worked better than you thought.Pipe thread plummers use might be good to use.I have no idea which one.great job I shall take a pound of your best pine you have? Just kidding!Ten stars!!

 

 

Thanks for the kind words.

Automotive RTV high temp gasket silicone should also work fine for the pipe threads.

Under heat it hardens like a rock.

Edited February 23, 2012 by oldguy

[allrocketspsl]

Thanks for the kind words.

RTV high temp gasket silicone should also work fine for the pipe threads.

Under heat it hardens like a rock.

 

good to know thanks!Im jealous!!!

[oldguy]

Eyeballing Triple Drum Charcoal (TDC)

 

 

Grain intact without shrinking much

 

 

Grain intact & some developed holes

 

 

A small percentage had a razor thin bronze sheen.

 

 

Very fast ignition in a charcoal chimney starter (about 5 or 6 X faster than lump hardwood, mesquite or briquettes)

 

I also weighed about a square inch of TDC against about a square inch of charcoal that was made in a normal retort & while still very light weight, the TDC charcoal was significantly heavier.

Edited February 23, 2012 by oldguy

[JFeve81]

Good job. Looks like it turned out great. Now where's the vid? Might not be much to see but I'd watch it. I will probably have to remember this thread as one day, if all the moons and planets align, I would like to build one on a smaller scale. Could use it for pyro and food charcoal.

[oldguy]

Some preliminary conclusions about my triple drum retort design:

 

Certainly a lot depends on your personal metalworking skills, tools, equipment and the parts available to you at inexpensive or at least reasonable prices.

So there are numerous variables involved depending on your individual situation.

 

Had I to build this triple barrel retort over again,( and plan to this spring). I would make a few changes.

With the caveat that those changes would involve some fairly simple welding.

Obviously, with adequate inlet draft (2 or more inches on both ends of the 55G firebox barrel) the firebox generates ample heat to perform the retorting task.

 

However, as designed & built there is (at least to me) an obvious bottle neck in the heat transfer from the lower firebox drum up into upper outer drum.

Caused by the bottleneck small diameter 6 inch flue between the upper and lower drums.

I would use additional sheet metal (55G drum sheet metal skin) to build a flue between them approximately 10 inches or more in diameter (without a damper).

Then simply weld that oversized flue into place between the two.

 

The reasoning behind this is that doings so would alleviate the bottleneck cause by the existing small 6 inch flue, allow far more rapid heat transfer from the firebox into the upper drums, and provide much more evenly distributed heat up and around the upper inner 30G drum.

 

Secondly, looking at the cost of insulating the firebox drum (as I did).

I am unsure if the benefit is worth the additional cost and labor. Instead (having numerous 55G open top drums on hand bought at $5 each).

I think it would be more cost effective and certainly more expedient to simply cut the ends off 2 or 3 more 55G open top type drums.

Slit them lengthwise and insert those addition sheet metal skins inside the firebox drum, increasing the sheet metal thickness X 3.

This would not have the same insulating quality as I built the prototype.

But would add more insulation factor than a single drum alone and certainly would increase the life expectancy of the firebox itself.

 

I also think rather than 2X6's, if 2x4's & better yet 2X2's were charred, the process would be more even & go quicker.

Also 2x2 - would fit right down the throat of a garbage disposal type charcoal grinder.

 

More thoughts & conclusions to follow ASAP.

Edited February 23, 2012 by oldguy

[oldguy]

Some other conclusions.

 

Unless you have a serious desire, want or need for large volumes of premium BP & Pyro grade charcoal.

Because of the expense & labor involved, a triple drum charcoal retort isn't for everyone.

Besides the overall expense of building the unit itself, you should also consider actual operating costs.

 

Unless you have a readily available inexpensive source or supply of firewood fuel.

Wood fuel costs alone would be considerable.

The same goes for the cost of the wood you intend to char.

 

Firing a fairly full load in the 30G retort drum (so far) results in roughly 20 or so pounds of charcoal.

That is just an educated guess, as I did not weigh this load, but will the next.

 

You can buy commercial mesh graded air float to 20 mesh charcoal from vendors like Hobby Chemical Supply or Skylighter for about $$3.50 to $6.50 a pound plus postage.

You can do the dollar math on that yourself. Considering commercial charcoal is already mesh graded, saves you considerable dirty work.

 

However, based on the assumption that commercial charcoal is made from a mix of hardwood, soft wood & whatever other sorts of wood the manufacture utilizes.

The quality of homemade charcoal is assumed to be superior, if you utilize optimal type wood and charring methods.

So, there is a trade off in relative reactivity, lift power, spark effects & BP speeds.

 

In addition, there is a high degree of self satisfaction and pride in start to finish production of premium homemade charcoal, not to mention associated bragging rights.

So, it's 6 dozen things one way, and another 6 dozen the other.

 

I would think this type & size charcoal retort would be ideal for clubs.

In that if some members shared metal working skills, tools & equipment to build one & the material costs were split amongst the club members that built it..

They individual cost to anyone involved would be minimal.

The unit could also pay for itself in short order by selling or horse-trading some of the charcoal it produces at meets, shoots & events.

 

If you were around & had the inclination.

It would not be a chore to produce 100+ lbs of premium charcoal a week with this retort.

 

　

Edited February 23, 2012 by oldguy

[oldguy]

I should make mention, as built there is no pressure relief pop off safety feature on the upper inner 30G drum.

For serious safety minded adults, that is not an issue.

 

But for kewl kids,big time pot smokers, heavy drinkers and the like, there should be.

 

It is easy to install one, by simply inserting an upright ¾ inch short pipe nipple on top the upper inner 30G drum.

Then setting a 1 inch steel pipe cap over then top of it as a weight .

Which would serve as a pop off pressure release, if/when someone forgot to open the proper valve

Edited February 24, 2012 by oldguy

[dan999ification]

i found my pine charcoal swells when cooked [maybe its not pine,unknown furniture wood very soft looks like pine], only the willow shrinks but i do cook green wood.

this picture of the bronze sheen: can we safely say that this is the mythical brown charcoal, more reactive, better yield etc, looks to have the same brown sheen i had on some willow a while back NOT undercooked wood, made the best bp ive ever seen.

is it possible to have a control batch [for im guessing dag] of charcoal cooked in the normal way with the same wood to compare the two after milling some bp, either way i think the difference will be noticable.

so happy to see this works like it should

 

dan.

 

 

[oldguy]

You can actually run 2 batches a day, if you start early in the day.

 

Once batch 1 is completed charring.

 

Close lower damper.

 

Remove upper out drum lid.

 

Which allows upper inner 30G drum to cool much faster.

 

Wait until upper inner drum is cool enough to touch & open (about 90 to 2 hours).

 

Open & unload.

 

Reload upper inner drum with another batch to char.

 

Close upper inner drum & upper outer drum.

 

Rekindle the firebox drum.

 

 

[oldguy]

Load containing some thin very clear white pine ½ X 4 inch wide random lengths. Retained around 85 or 90% of its original volume.

Removed from the retort warm, watched pieces go pyrophoric SPARKING right in my hand.

It made tiny snap, crackle, pop sounds, actuality distorting as I held pieces, twisting, cracking as if it was released from a vacuum or something.

Really strange, almost magical like.

 

 

 

　

 

　

Edited February 27, 2012 by oldguy

[dagabu]

Not the last word on the subject by far but fire investigators run into this phenomena as well with super reactive charcoals.

"The theory from the scientific community (as I understand it) is that the low temperature cooks the wood turning it in to charcoal which we all know is more reactive and the more porous the charcoal is the more oxygen it absorbs and the more reactive it becomes."

You may have created the scaffold for pyrophoricity to take place by using a very low temp conversion to carbon that when exposed to an oxygen rich environment, went pyrophoric. Bet you cant do it again!

-dag

[oldguy]

Bet you cant do it again! -dag

 

LOL, I don’t want it to do that again.

 

Only the thin 1/2 x 4 inch random lengths of white pine did it.

 

It just surprised me to have it crinkle, crack & spark like that right in my hand.

 

Lesson learned, don’t open the retort drum when it is as warn as it was.

 

 

[oldguy]

 

Minimal shrinkage every load so far.

 

Looks undercooked. But, almost as soft as pop corn.

 

Perplexing that pieces with a brown or bronze sheen are black as coal tar inside.

 

[dagabu]

My mouth is watering! I am betting that you have some awesomely reactive charcoal there. It looks like it is weathered and not cooked at all, the coppery tint makes it look like it's fresh wood.

 

Absolutely gorgeous.

 

-dag

[oldguy]

I am thinking the internal retort temperatures are around 340C - 644F range.

Unloading, shows everything coal black near the center of the retort drum load, where direct higher heat hits it.

While both ends of the load further from the direct heat show the copper bronze sheen.

There must be an explanation why the loads only minimally shrink.

Impart I think it’s because of the lower temperature, in combination with pressure.

 

 

 

 

[allrocketspsl]

looks like they have been burning then started burning from the inside out,weird looking pieces with all the detail of wood,you may have stumbled onto a new exciting charcoal mate Im putting in a bid of $15 for a pound not broken up I wil grain it to different meshes

00

please please please

Edited February 26, 2012 by allrocketspsl

[oldguy]

I am sending out a few box's for others to test.

Other than that, I have a use for all I can make.

Sadly, I don't plan to sell any.

Sorry