make charcoal?

[chilled_fluorine]

The challenge is: I have a coffe can and some pieces of wood, now how do I make charcoal with them?I really hate the method of heating the can in an external fire, the wood should be it's own fuel for pyrolysis. Please help?

[zapatos]

This is an example of making charcoal in a large drum. Simply downsize for the container you are using.

 

Making your own charcoal

 

--------------------------------------------------------------------------------

 

 

Using a cold chisel prepare the drum by making five 50mm (2in) holes in one end and completely removing the other. Knock-up the cut edge of the open end to form a ledge (Note, the lid will have to placed back on this ledge and made airtight).

 

Position the drum, open end upwards, on three bricks to allow an air flow to the holes in the base.

 

Place paper, kindling and brown ends (incompletely charred butts from the last burn) into the bottom of the drum and light.

 

 

Once it is burning well, load branchwood at random to allow air spaces until the drum is completely full. Keep the pieces to a fairly even diameter but put any larger ones to the bottom where they will be subjected to a longer burning.

 

 

When the fire is hot and will clearly not go out, restrict the air access around the base by using earth placed against it, but leaving one 100mm (4in) gap. Also place the lid on top, leaving a _small_ gap at one side for smoke to exit.

 

Dense white smoke will issue during the charring process. When this visibly slows, bang the drum to settle the wood down, creating more white smoke.

 

 

When the smoke turns from white (mainly water being driven off) to thin blue (charcoal starting to burn) stop the burn by firstly closing off all air access to the base using more earth, and secondly by placing the lid firmly on its ledge, and making it airtight by the addition of of sods and soil as required. The burn will take between three and four hours.

 

After cooling for about 24 hours, the drum can be tipped over and the charcoal emptied out onto a sheet for grading and packing.

 

 

Source: Traditional Woodland Crafts. Raymond Tabor. Published by Batsford,London,UK ISBN 0-7134-7138-7

http://www.eaglequest.com/~bbq/charcoal/

[JMJones0424]

The challenge is: I have a coffe can and some pieces of wood, now how do I make charcoal with them?I really hate the method of heating the can in an external fire, the wood should be it's own fuel for pyrolysis. Please help?

 

I think you will find that a "top lit up draft" (TLUD) stove is exactly what you are looking for. Designs are abundant on the internet

[Essay]

The challenge is: I have a coffe can and some pieces of wood, now how do I make charcoal with them?I really hate the method of heating the can in an external fire, the wood should be it's own fuel for pyrolysis. Please help?

I've been playing with a modification of the basic TLUD, called TLOD (top-lit opposite draft) tech.

 

If you create a "sealed" vortex above the can of burning fuel, you can reduce ash production and improve your yield of char up to four times. This is an active process, requiring a little extra power to generate an active, directed, airflow.

===

 

The can of fuel (the active can) is open on top, and it needs 5-6 small holes punched into the sides--just above the bottom. A kitchen-style can punch/bottle opener, with just the sharp tip punched through the can's side, often works well for both distance and size.

 

Place this (active) can inside of a larger diameter can (so there are a few inches or so between the outside of the inner (active) can and the inside of the larger can. The larger (outer) can needs a lid, with a hole in the center, for heat/flame to rise out of. The hole in the center of this lid should be about 1/3 to 1/2 of the diameter of the inner can.

 

The distance between the top of the inner can, and the lid of the outer can, should be at least a few inches--less than or similar to the airspace between the can's radii--to allow an effective vortex to form easily. Given a good vortex, the farther the lid is from the top of the inner can, the less efficiently will the smoke be sealed within and below the vortex; so this, and the size of the exit hole, can be adjusted to improve the shape of the vortex and thus efficiency of the burn.

 

A battery operated (solar rechargeable) pump (normally used to inflate air mattresses) produces enough airflow to create a vortex for a coffee can / 5 gal. metal bucket system. At least it worked for me this past Spring.

 

Feed the airflow into the side (near the bottom) of the outer can, pointed around the perimeter of the can (not straight toward the center, but radially around the inside of the can). The air pumped in circulates around the outside of the inner can, and thus pulls some air out through the small punched holes (Venturi effect), carrying it up to the top where it continues circling and being pushed toward the center hole in the lid... to exit. This creates a vortex (tornado) which dips into the inner can (where a small fire has been started with kindling on top of the main fuel).

 

The vortex becomes filled with smoke (sucked out through small holes near bottom of inner can by Venturi force). The vortex ignites and continues to heat the fuel below--after the kindling is burned. The heated fuel produces smoke, which feeds the burning vortex, which continues heating the fuel. Smoke pulled down through the fuel improves the char yield, as carbon-rich smoke fractionates and some carbon redeposits onto the fuel.

 

A burning tornado is fun to watch, but when smoke production ceases (enough to keep the vortex burning), then the fuel has been converted to charcoal. Turn off the airflow and continue cooking with perfect, rapidly produced, hot coals--or dump the char into water or mud to quench the process. Hot char will soak up, and retain, lots of water (or compost tea) to create a great onsite soil amendment (biochar). Suffocating the char will keep it dry and easy to process and transport when cooled.

===

 

Balancing the depth of the vortex (airflow speed/volume), with the little holes in the lower side of the inner can, is the hard part. The vortex need to broadly dip into the inner can (to create an "air curtain" and low oxygen conditions below the vortex), but not so far that it dips deeply into the fuel. Enlarging the small holes will shrink the vortex depth for a given airflow configuration; so start with very small holes.

 

[A hair dryer (or blowdryer) will work with two 5 gal. buckets (one as a stand, below the other active bucket), inside of a trash can.] Did this over the past summer.

 

[A leaf blower should work with a 50 gal. oil drum, inside of a sheet-metal "air guide" or other, larger drum with lid.] Haven't done this yet.

 

Check out woodgasCampstove dotcom, or woodgas campstoves in general, for examples and pictures of this basic "active airflow principle" applied to improved charcoal production. Most sites have errors about the airflow, but a few sites show the correct diagrams for the airflow related to the inner (active) can.

===

 

It's a way of burning the smoke separately, instead of burning the fuel directly, to turn waste biomass--even sewage and plastics--into char. Smoke-free burning, which produces reduced carbon; what a deal!

 

~

[chilled_fluorine]

This is an example of making charcoal in a large drum. Simply downsize for the container you are using.

 

 

http://www.eagleques.../~bbq/charcoal/

 

I'm still trying to find one of those big oil drums... It didn't work when I tried to scale it down a few months ago. I'm going to try going full scale, now that I have more than enough wood.

 

I've been playing with a modification of the basic TLUD, called TLOD (top-lit opposite draft) tech.

 

If you create a "sealed" vortex above the can of burning fuel, you can reduce ash production and improve your yield of char up to four times. This is an active process, requiring a little extra power to generate an active, directed, airflow.

===

 

The can of fuel (the active can) is open on top, and it needs 5-6 small holes punched into the sides--just above the bottom. A kitchen-style can punch/bottle opener, with just the sharp tip punched through the can's side, often works well for both distance and size.

 

Place this (active) can inside of a larger diameter can (so there are a few inches or so between the outside of the inner (active) can and the inside of the larger can. The larger (outer) can needs a lid, with a hole in the center, for heat/flame to rise out of. The hole in the center of this lid should be about 1/3 to 1/2 of the diameter of the inner can.

 

The distance between the top of the inner can, and the lid of the outer can, should be at least a few inches--less than or similar to the airspace between the can's radii--to allow an effective vortex to form easily. Given a good vortex, the farther the lid is from the top of the inner can, the less efficiently will the smoke be sealed within and below the vortex; so this, and the size of the exit hole, can be adjusted to improve the shape of the vortex and thus efficiency of the burn.

 

A battery operated (solar rechargeable) pump (normally used to inflate air mattresses) produces enough airflow to create a vortex for a coffee can / 5 gal. metal bucket system. At least it worked for me this past Spring.

 

Feed the airflow into the side (near the bottom) of the outer can, pointed around the perimeter of the can (not straight toward the center, but radially around the inside of the can). The air pumped in circulates around the outside of the inner can, and thus pulls some air out through the small punched holes (Venturi effect), carrying it up to the top where it continues circling and being pushed toward the center hole in the lid... to exit. This creates a vortex (tornado) which dips into the inner can (where a small fire has been started with kindling on top of the main fuel).

 

The vortex becomes filled with smoke (sucked out through small holes near bottom of inner can by Venturi force). The vortex ignites and continues to heat the fuel below--after the kindling is burned. The heated fuel produces smoke, which feeds the burning vortex, which continues heating the fuel. Smoke pulled down through the fuel improves the char yield, as carbon-rich smoke fractionates and some carbon redeposits onto the fuel.

 

A burning tornado is fun to watch, but when smoke production ceases (enough to keep the vortex burning), then the fuel has been converted to charcoal. Turn off the airflow and continue cooking with perfect, rapidly produced, hot coals--or dump the char into water or mud to quench the process. Hot char will soak up, and retain, lots of water (or compost tea) to create a great onsite soil amendment (biochar). Suffocating the char will keep it dry and easy to process and transport when cooled.

===

 

Balancing the depth of the vortex (airflow speed/volume), with the little holes in the lower side of the inner can, is the hard part. The vortex need to broadly dip into the inner can (to create an "air curtain" and low oxygen conditions below the vortex), but not so far that it dips deeply into the fuel. Enlarging the small holes will shrink the vortex depth for a given airflow configuration; so start with very small holes.

 

[A hair dryer (or blowdryer) will work with two 5 gal. buckets (one as a stand, below the other active bucket), inside of a trash can.] Did this over the past summer.

 

[A leaf blower should work with a 50 gal. oil drum, inside of a sheet-metal "air guide" or other, larger drum with lid.] Haven't done this yet.

 

Check out woodgasCampstove dotcom, or woodgas campstoves in general, for examples and pictures of this basic "active airflow principle" applied to improved charcoal production. Most sites have errors about the airflow, but a few sites show the correct diagrams for the airflow related to the inner (active) can.

===

 

It's a way of burning the smoke separately, instead of burning the fuel directly, to turn waste biomass--even sewage and plastics--into char. Smoke-free burning, which produces reduced carbon; what a deal!

 

~

 

Wow, that was really long! There were a few things I was unsure of while reading it. Through what opening does the blower blow? Could you try to give some more specific measurements? Maybe a diagram or two? Great post! For some reason this seems familiar to me.

[Essay]

Through what opening does the blower blow? Could you try to give some more specific measurements?

 

Good points!

 

 

The blower gets jammed into a single hole formed on the side of the outer can, at the bottom, and is angled so that it blows around (parallel to) the perimeter--inside of the outer can. The blower is also parallel to the ground, or bottom of the barrel; it is not pointing upward, but is blowing air around in a circle at the bottom. As more air is blown in, the swirling air pushes up to the top so it can exit through the hole in the lid--still swirling quickly around. That is what creates the vortex that dips down into the inner can.

 

I'll try to take a photo. It would be easier than these thousand words.

~

[chilled_fluorine]

I think you will find that a "top lit up draft" (TLUD) stove is exactly what you are looking for. Designs are abundant on the internet

 

Really? I can't find any, just videos of people using them.

[JMJones0424]

http://www.lmgtfy.com/?q=tlud

[chilled_fluorine]

http://www.lmgtfy.com/?q=tlud

 

I already tried google, could you give me a specific link?

[Essay]

I'll try to take a photo. It would be easier than these thousand words.

 

 

I took pictures of the various pieces. They are all backyard, "found" items, except for an extra trashcan cover/lid--and a steel bowl that holds the fuel/wood chunks. I bought a 5 quart stainless drinking dish at a pet store, and punched 6 holes around the lower perimeter with a nail. It fits into the bottom of the tall black bucket, which is placed atop the shorter galvanized washtub--both inside of the trash can. This brings the sides of the (black) inner bucket up to [barely below] even with the top of the (outer) trash can.

 

The slightly domed lid (with the hole cut in center), from a larger trash can, provides enough space above the top of the inner bucket for air to escape--and a vortex to form--as the rapidly spinning blower air rises between the walls of the inner and outer buckets and exits through the trashcan lid.

 

The top inner bucket (black in this case) needs small holes around the base, like the steel liner has, to permit (Venturi) entrainment of smoke by the rising "input" or blower air... or to permit the vortex to push smoke out into the blower air. These small holes thus permit the vortex to "seal" the inner can--forming an air curtain across the top--without completely smothering the fire.

 

Note the original, tight-fitting lid in background, and the new, oversized lid (with hole cut in center) on the right. It's nice to be able to place, remove, or replace the lid easily; and to have a tight-fitting lid available for smothering the whole process during trials with different configurations/inner buckets. Note hole in side, at the base, of the trashcan.

 

Note stainless liner/bowl in bottom of black bucket.

Also, Note hair dryer/blower. It has high/low speeds and no/low/high heat options, so using the "no heat" option it is just a blower. Low speed is more than enough airflow for this setup. I don't always use the plexiglass tube, but it better shows the intended airflow--around the perimeter.

 

Hmmm. I have more pictures, but seem to have maxed out the file limit on posting.

Here are the captions for those pictures--with timestamps from the pm of Aug. 26, 2012.

 

 

4:55. Note nail-holes near the bottom of stainless liner. Three holes on other side also.

 

6:13. Aside from the one big chunk and the kindling at center, the bowl is filled with medium sized chunks like the two or three visible around the kindling.

 

6:14. All set and ready to add a lit match.

 

6:17. Match added and lid replaced, and at

 

6:18. The kindling is burning.

 

6:19. Blower has been turned on.

 

6:20. The fire grows quickly.

 

6:21. Diffuse flames still swirl after exiting, while concentrated flames swirl in a blur near the bottom of the inner bucket, above and around the fuel.

 

6:21. It's hard to get a picture looking down into the vortex, without getting scorched a bit. Yowch! Notes licks of burning smoke trailing off from dark chunks of fuel at bottom.

 

6:22. Burning the woodsmoke vigorously.

 

6:23. Most of the easily generated woodsmoke has been liberated. The fire is calming down, but the fan has been running at the same speed throughout.

 

6:24. Fire is almost out. Note lick of smoke curling around at left, which ignited a moment later.

 

6:25. Only charcoal remaining. Time to turn off the blower and quench the char.

 

6:26. Char dumped into clay dish and misted with hose.

 

[chilled_fluorine]

I took pictures of the various pieces. They are all backyard, "found" items, except for an extra trashcan cover/lid--and a steel bowl that holds the fuel/wood chunks. I bought a 5 quart stainless drinking dish at a pet store, and punched 6 holes around the lower perimeter with a nail. It fits into the bottom of the tall black bucket, which is placed atop the shorter galvanized washtub--both inside of the trash can. This brings the sides of the (black) inner bucket up to [barely below] even with the top of the (outer) trash can.

 

The slightly domed lid (with the hole cut in center), from a larger trash can, provides enough space above the top of the inner bucket for air to escape--and a vortex to form--as the rapidly spinning blower air rises between the walls of the inner and outer buckets and exits through the trashcan lid.

 

The top inner bucket (black in this case) needs small holes around the base, like the steel liner has, to permit (Venturi) entrainment of smoke by the rising "input" or blower air... or to permit the vortex to push smoke out into the blower air. These small holes thus permit the vortex to "seal" the inner can--forming an air curtain across the top--without completely smothering the fire.

 

Note the original, tight-fitting lid in background, and the new, oversized lid (with hole cut in center) on the right. It's nice to be able to place, remove, or replace the lid easily; and to have a tight-fitting lid available for smothering the whole process during trials with different configurations/inner buckets. Note hole in side, at the base, of the trashcan.

 

Note stainless liner/bowl in bottom of black bucket.

Also, Note hair dryer/blower. It has high/low speeds and no/low/high heat options, so using the "no heat" option it is just a blower. Low speed is more than enough airflow for this setup. I don't always use the plexiglass tube, but it better shows the intended airflow--around the perimeter.

 

Hmmm. I have more pictures, but seem to have maxed out the file limit on posting.

Here are the captions for those pictures--with timestamps from the pm of Aug. 26, 2012.

 

 

4:55. Note nail-holes near the bottom of stainless liner. Three holes on other side also.

 

6:13. Aside from the one big chunk and the kindling at center, the bowl is filled with medium sized chunks like the two or three visible around the kindling.

 

6:14. All set and ready to add a lit match.

 

6:17. Match added and lid replaced, and at

 

6:18. The kindling is burning.

 

6:19. Blower has been turned on.

 

6:20. The fire grows quickly.

 

6:21. Diffuse flames still swirl after exiting, while concentrated flames swirl in a blur near the bottom of the inner bucket, above and around the fuel.

 

6:21. It's hard to get a picture looking down into the vortex, without getting scorched a bit. Yowch! Notes licks of burning smoke trailing off from dark chunks of fuel at bottom.

 

6:22. Burning the woodsmoke vigorously.

 

6:23. Most of the easily generated woodsmoke has been liberated. The fire is calming down, but the fan has been running at the same speed throughout.

 

6:24. Fire is almost out. Note lick of smoke curling around at left, which ignited a moment later.

 

6:25. Only charcoal remaining. Time to turn off the blower and quench the char.

 

6:26. Char dumped into clay dish and misted with hose.

 

 

Too bad I can't see the other photos... And I'm still not sure how I would go about making that thing. Maybe it's my ADHD acting up. I'm a very visual learner, just a picture of everything would enlighten me instantly.

[Essay]

Too bad I can't see the other photos... And I'm still not sure how I would go about making that thing. Maybe it's my ADHD acting up. I'm a very visual learner, just a picture of everything would enlighten me instantly.

 

I just posted them in an album on facebook:

http://www.facebook....&type=1

 

But those pictured above are all the pieces. The washtub fits inside of the trashcan, upside down, to serve as a base for elevating the black bucket--which is also then inside the trashcan. I just center them by eye, it's a pretty forgiving system. There is one picture in the album looking down through the lid onto the fuel--before lighting.

 

[edit]The washtub (pictured in post above) is upside down in the picture (note handles on ground), which is the way it goes into the trashcan; but any bucket about that size will work, it is just a stand to elevate the active (black) bucket.

 

This stainless bowl/liner fits inside of the black bucket (as pictured in post above): [/edit]

Note nail-holes near the bottom. Three holes on other side of this stainless steel bowl/liner also.

 

 

Blower (as pictured in the post above) has just been turned on. This is looking down into the stainless bowl in bottom of the black bucket.

~

Edited August 28, 2012 by Essay

[chilled_fluorine]

I just posted them in an album on facebook:

http://www.facebook....&type=1

 

But those pictured above are all the pieces. The washtub fits inside of the trashcan, upside down, to serve as a base for elevating the black bucket--which is also then inside the trashcan. I just center them by eye, it's a pretty forgiving system. There is one picture in the album looking down through the lid onto the fuel--before lighting.

 

[edit]The washtub (pictured in post above) is upside down in the picture (note handles on ground), which is the way it goes into the trashcan; but any bucket about that size will work, it is just a stand to elevate the active (black) bucket.

 

This stainless bowl/liner fits inside of the black bucket (as pictured in post above): [/edit]

Note nail-holes near the bottom. Three holes on other side of this stainless steel bowl/liner also.

 

 

Blower (as pictured in the post above) has just been turned on. This is looking down into the stainless bowl in bottom of the black bucket.

~

Alright, I think I get it. For some reason I can't see the Facebook images. You really should be more specific about the hole sizes though. Are they 1 millimeter or 5 cm? Could be either, I don't have a clue. Thanks for putting up with my seemingly endless stream of questions.

[Essay]

Alright, I think I get it. For some reason I can't see the Facebook images. You really should be more specific about the hole sizes though. Are they 1 millimeter or 5 cm? Could be either, I don't have a clue. Thanks for putting up with my seemingly endless stream of questions.

Thanks for getting me to take some pictures!

 

Yeah, F'nBook! Ya gotta log in to see anything! I'll update this if I get all of them posted elsewhere, but most of the critical ones are up here now.

===

 

 

There are many examples of similar stoves on You-Tube (search Rocket Stoves, biochar stoves, or gasifier stoves), made from coffee cans, etc.; but most are passive or use direct forced air, instead of recycling the smoke in a vortex. Any flame that exits should be diffuse and clean (see photo), rather than dense and sooty.

 

 

 

* 6:21. Diffuse flames still swirl after exiting, while concentrated flames swirl in a blur near the bottom of the inner bucket, above and around the fuel.

===

 

 

Overall:

Six 1/8-inch holes in steel 5-qt. dish, inside of 11-inch diameter black bucket (with twelve 1/8-inch holes around its base), inside of 18-inch diameter trash can (with 1 hole around its base to permit the blower nozzle), and a 15-cm --just under 6-inch-- hole centered in an oversized (22-inch) lid on top. [Not Pictured here; see above]

===

 

 

* 6:13. Aside from the one big chunk and the kindling at center, the bowl is filled with medium sized chunks like the two or three visible around the kindling. Stainless bowl is set down into bottom of bucket.

===

 

A different, 11-inch diameter, tube could be used to extend the sides of the stainless bowl up to the height which the black bucket currently does; instead, the black bucket only serves that purpose now--but it was convenient--or just use the black bucket without the stainless liner inside (if you have a strong enough bucket).

 

The black bucket is raised (set atop the washtub) to rest just within one inch of the trashcan lid. A different bucket/washtub, which raised the black bucket up to only within 2 or 3 inches of the lid would probably also work, or might work better. But however you raise the 11-inch/active unit up nearer to the trashcan lid, you should help to reduce the open-air space below that active unit/bucket, and to guide the airflow around the perimeter and upward, so the vortex can form just below the exit hole.

 

~Cheers!

 

p.s. Experimenting with the exit hole size would be a good, next project.

Edited August 29, 2012 by Essay