OLDGUYS TRIPLE BARREL CHARCOAL RETORT DESIGN

[oldguy]

Dag,

I am shooting for a relatively consistent 300'C (572 F) temperature for around 3 (+/-) hours.

With the way the firebox is insulated & the rest of the retort is set up..

I don't think you will see much "cherry red" metal.

Especially so since it has two draft control dampers.

1 between the firebox & upper outer drum.

The other in the stove pipe atop the upper outer drum.

 

I think steel begins to glow faintly red at about 600C (1110F).

 

LOL, I think I will "ignite" it with Visco......

Edited February 14, 2012 by oldguy

[dagabu]

Dag,

I am shooting for a relatively consistent 300'C (572 F) temperature for around 3 (+/-) hours.

With the way the firebox is insulated & the rest of the retort is set up..

I don't think you will see much "cherry red" metal.

Especially so since it has two draft control dampers.

1 between of the firebox & upper outer drum.

The other in the stove pipe atop the upper outer drum.

 

I think steel begins to glow faintly red at about 600C (1110F).

 

LOL, I think I will "ignite" it with Visco......

 

 

Wink, wink, it was tongue-in-cheek OG,

 

Lets see that bugger all fired up and lets get us some charcoal out of that thing. I would really be interested to see what kind of power standard BP can gain with a controlled burn on a reactive charcoal.

 

-dag

[Peret]

You're going to need some way to grind the results, sothing that takes less effort than turning a meat grinder for hours at a time. I saw a post on Passfire that said people are using kitchen waste disposal units as charcoal grinders - that seems like a good idea, providing you use a new one (or at least a clean one) and keep it dry.

[dagabu]

You're going to need some way to grind the results, sothing that takes less effort than turning a meat grinder for hours at a time. I saw a post on Passfire that said people are using kitchen waste disposal units as charcoal grinders - that seems like a good idea, providing you use a new one (or at least a clean one) and keep it dry.

 

The stainless steel ones seem to last a lot longer for whatever reason.

 

-dag

[oldguy]

Thanks Peret,

 

Using a garbage disposal to grind charcoal is an ingenious idea.

 

If you mounted a hvy duty garbage disposal in a single SS sink.

 

Then mounted the sink in a small metal table top (on casters).

 

Then secured a large pro grade dust type collector bag to the unit.

 

That would be one hell of a set up.

 

Another build is in order with that idea.

 

 

I can reduce barrel run charcoal chunks to about ¼ inch minus using my big old electric garden mulcher / shredder.

But, that is one hell of a dusty job. I did a large tote full last fall & ended up looking like a coal miner from it.

Covering the shredder with an old bed sheet & misting it down with a garden hose, keeps the dust down.

Charcoal gets a little damp. But will air dry in the hot sun quickly.

Edited February 14, 2012 by oldguy

[oldguy]

The stainless steel ones seem to last a lot longer for whatever reason.

 

-dag

 

Stainless steel what?

The grinding impeller?

 

EDIT TO ADD:

Never mind.

Did some shopping.

The SS ones are often 1 HP + & seem to be better built than the cheaper models.

Edited February 14, 2012 by oldguy

[dagabu]

Thanks Peret,

 

Using a garbage disposal to grind charcoal is an ingenious idea.

 

If you mounted a hvy duty garbage disposal in a single SS sink.

 

Then mounted the sink in a small metal table top (on casters).

 

Then secured a large pro grade dust type collector bag to the unit.

 

That would be one hell of a set up.

 

Another build is in order with that idea.

 

I can reduce barrel run charcoal chunks to about ¼ inch minus using my big old electric garden mulcher / shredder.

But, that is one hell of a dusty job. I did a large tote full last fall & ended up looking like a coal miner from it.

Covering the shredder with an old bed sheet & misting it down with a garden hose, keeps the dust down.

Charcoal gets a little damp. But will air dry in the hot sun quickly.

 

 

Stainless steel what?

The grinding impeller?

 

EDIT TO ADD:

Never mind.

Did some shopping.

The SS ones are often 1 HP + & seem to be better built than the cheaper models.

 

Yes, yes and yes. SST has the SST impeller and housing and is not gummed up by the tar you will be introducing when grinding, they also have heavier bearings and as you say, have more robust motors. I have seen a few setups (one right at PGI in Appleton) and most use a pillowcase to catch the coal and another used a three ply setup, one very fine cloth on the very outside (1000 thread count sheets) and standard sheet material inside of that and broadcloth in the inside. It seemed that he held most of the fine dust inside that setup.

 

There is a guy in Big Sky country that sells charcoal and he uses a big plywood box with a sheet covering the far end, he says that the coal drops out pretty fast and that by the time it reaches the far side, the only thing left is talc sized charcoal. That way he doesn't have to empty anything and he just lifts the sheet (really a canvas tarp) and scoops it into garbage bags for sale.

 

He looks like a coal miner most of the time...

 

-dag

Edited February 14, 2012 by dagabu

[allrocketspsl]

Yes, yes and yes. SST has the SST impeller and housing and is not gummed up by the tar you will be introducing when grinding, they also have heavier bearings and as you say, have more robust motors. I have seen a few setups (one right at PGI in Appleton) and most use a pillowcase to catch the coal and another used a three ply setup, one very fine cloth on the very outside (1000 thread count sheets) and standard sheet material inside of that and broadcloth in the inside. It seemed that he held most of the fine dust inside that setup.

 

There is a guy in Big Sky country that sells charcoal and he uses a big plywood box with a sheet covering the far end, he says that the coal drops out pretty fast and that by the time it reaches the far side, the only thing left is talc sized charcoal. That way he doesn't have to empty anything and he just lifts the sheet (really a canvas tarp) and scoops it into garbage bags for sale.

 

He looks like a coal miner most of the time...

 

-dag

 

if anyone ever needs a cheap disposlal let me know at Lowes people bring them back all the time then we resell cheap but even cheaper if I buy.Bought one brand new for a guy and a 129.00 dollar 3/4 was only 25.00 dollars.Been awhile since I have seen one but when I was in plumbing dept had them all the time so I can let a friend in plumbing know so we will know

[oldguy]

if anyone ever needs a cheap disposlal let me know at Lowes people bring them back all the time then we resell cheap but even cheaper if I buy.Bought one brand new for a guy and a 129.00 dollar 3/4 was only 25.00 dollars.Been awhile since I have seen one but when I was in plumbing dept had them all the time so I can let a friend in plumbing know so we will know

 

Your local Craigslist is another good source.

 

I am pondering mounting one in the lid of a short open top type steel or plastic drum.

Once mounted, place lid on drum, close the drum tight with clamp ring.

I would think that would contain the dust well, and also serve as a container.

 

[oldguy]

I shortened the upper inner drum gas intake.

Reason being so I could fit smaller containers in the 30G drum.

That way I could run some balsa or western cedar at once, but in individual containers.

Reason being with the price of wood like balsa & other exotics.

 

I would not want to mix them up.

 

 

 

[oldguy]

 

 

 

 

 

[NightHawkInLight]

Hey look at that, it can burn things! That's a good start. Looking forward to seeing some charcoal. A picture of the gas venting into the fire would be interesting to see also once it really gets going.

[oldguy]

This was just a TRIAL run with the upper inner drum empty, to burn off any paint & see how hot it gets.

 

So, no flammable gas is emitting into the firebox.

Otherwise I would have taken a picture of it.

 

Soon enough I will make a load of charcoal in it.

 

 

[NightHawkInLight]

You have superhuman patience. No way I could have fired that up without throwing some sticks in the cooker. Were you able to get inside the top to get a reading of what the 33 gallon heated up to?

[marks265]

I don't know if this is was discussed or not, but I would keep track of the stack temp below the damper and see if that measurement would be good enough to use against your desired cooking temp. It would eventually keep you from maybe opening the door so often. Or do plan on using a high temp thermocouple with a bulkhead connector in the top drum? I bet it feels good to have made the first fire! Congrats!

Mark

[oldguy]

I don't know if this is was discussed or not, but I would keep track of the stack temp below the damper and see if that measurement would be good enough to use against your desired cooking temp. It would eventually keep you from maybe opening the door so often. Or do plan on using a high temp thermocouple with a bulkhead connector in the top drum? I bet it feels good to have made the first fire! Congrats!

Mark

 

Part of this test was to see if I could get the upper inner drum heated to the sweet spot (300 C / 572 F) & maintain that temperature for as long as I want. It was just shy of that at around 550F. With the little blower on, it would hit +600F. So, it will perform in the range I was hoping for.

 

Besides the slider draft in the cast iron door. I installed a 1 inch pipe fitting just below the door, so I could attach the little blower there. I think if a person installed three one inch fittings side by side there. It would allow enough addition draft so the blower would not be needed.

 

Other than that the sumbitch appears to operate almost perfectly.

 

http://www.ebay.com/itm/330578877735?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Do you think this Type K thermocouple would do the trick?

 

　

 

　

 

Edited February 16, 2012 by oldguy

[marks265]

Yep, I think it would be fine. The stainless steel probe can take the heat but I would only leave it in long enough to take a measurement at least until you are sure it won't get too hot and melt the cord end. Definitely stay with the 11.5" probe because the junction is at the end of the stainless tube. I hate infrared heat sensors because material surface reflectivity will throw the temp off somewhat. If you poke a small hole and slide it back so that it just stays in may also work. If it were me I would want to slide it in far enough to hit the inside steel drum to take the temp reading and then pull it back. With all tinkering you will find your liking. I just figure the inner drum steel temp would tell you what is going on with the charcoal.

If the temp runs away during production decrease the fan air intake to reduce flow. This will still supply a steady air flow at a reduced rate to keep wild swings in temp to a minimum.

 

Hope this helps. Once again, way cool stuff!!!

Mark

[oldguy]

After the prototype paint burn off & heat test today.

I began to think what I could have done differently to increase the units functionality & efficiency.

 

The drawback as built is inadequate natural draft (without the blower).

Secondly, there is uneven heat distribution to the upper inner drum.

Obviously, one end of the upper inner drum gets a lot more heat than the other.

 

So, after pondering those shortcomings.

I have decided to do a retrofit to improve the units draft & heat distribution to the upper inner drum.

No major changes, just going to move the flues.

Plus provide firebox draft from both ends as depicted below.

 

My thinking is this, by configuring natural draft at both ends of the firebox = hotter fire = more heat (no blower needed).

By centering the firebox & upper flue = more evenly heated upper inner drum.

 

Any constructive comments or suggestions?

 

Edited February 16, 2012 by oldguy

[oldguy]

I also think I will plumb a piece of rigid ¼ inch stainless steel tube through the outer upper 55G drum into the inner 30G drum with swagelock type fittings & a cap or plug on the outer exposed end.

That way I can remove the cap or plug & slide in the 11.5 inch stainless steel thermocouple probe through it into the inner upper 30G drum at will.

I cannot think of any better way of getting a consistent precise temperature reading inside the upper inner drum.

 

 

[oldguy]

I came across this infrared photo of an uninsulated barrel stove in operation.

The only modification being a fire view plate installed in the cast iron front door.

 

It's draft is only through the cast iron slider on the front of the door.

 

It's averaged out medium outer skin operating temperature is only 337 F.

 

This makes it painfully obvious that to dramatically increase the inner average medium operating temperate requires significantly more draft than the cast iron slider mechanism alone on the door can provide. With the flue centered I believe around 2 additional inches of natural draft orifice on each end of the fire box drum should allow enough draft to get the temps well within the range required here. .

 

 

　

Edited February 16, 2012 by oldguy

[dagabu]

Part of this test was to see if I could get the upper inner drum heated to the sweet spot (300 C / 572 F) & maintain that temperature for as long as I want. It was just shy of that at around 550F. With the little blower on, it would hit +600F. So, it will perform in the range I was hoping for.

 

Besides the slider draft in the cast iron door. I installed a 1 inch pipe fitting just below the door, so I could attach the little blower there. I think if a person installed three one inch fittings side by side there. It would allow enough addition draft so the blower would not be needed.

 

Other than that the sumbitch appears to operate almost perfectly.

 

http://www.ebay.com/itm/330578877735?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Do you think this Type K thermocouple would do the trick?

 

Type K thermocouples are good for −200° C to +1350° C / -328° F to +2462° F range but get twitchy around 650° F as the nickle reaches it's curie point the first time. There are loads of replacement probes available for this unit that can stand continuous contact without melting. Fill a glass with ice and add water, stir and check the temp, it should be 32° F / 0° C.

It looks great to me and I agree with NHIL, you are a saint how patient you are. BURN, BURN, BURN!!! LOL!

-dag

[oldguy]

Dag,

 

Thanks for the kind words & encouragement.

 

Since I conceived the method & publicly posted it.

I am honor bound to see it through to whatever optimal operational range that I can achieve.

So, the burden is on me to do just that.

 

Otherwise it would be just a half assed idea, without any proof of functionality.

 

Secondly, I would hate for anyone to go to the expense of building this type charcoal retort, if it did not function as I stated.

So, I will keep on keeping on until I achieve the goal, or fail.

The concept is sound. I don’t think failure is on the menu.

 

 

[Arthur]

If you consider cooking sawdustyou may find need for a rotary handle to tumble the sawdust drum as it cooks otherwise the centre of the sawdust is too well insulated by the rest of it to cook.

[dagabu]

If you consider cooking sawdustyou may find need for a rotary handle to tumble the sawdust drum as it cooks otherwise the centre of the sawdust is too well insulated by the rest of it to cook.

 

I posted this a short while ago but if you use taper tubes inside the report drum to separate the sawdust, the burn is much more even.

 

 

-dag

[oldguy]

This remodel fits right in the DIRTY JOB category.

 

Inspection shows bulk of the flue heat was on the far end of the upper inner drum.

Retrofit will cure that defect

 

 

Edited February 17, 2012 by oldguy