Making charcoal

[Don P]

While the guys were fussing and shimming the last rows of skip sheathing on the barn roof I started cleaning up the pasture we've been sawing in. Some minor mountains of slabs and edgings and a heap of docked tops. We had been talking about charcoal and there were a couple of old drums in the windrow so I decided to 'speriment at being a collier. I lit it through a 4" bung hole in the bottom and then plugged that after it got going good. Then I fed it all day, definitely not the fast way to get rid of a pile! You can barely see the edge of the lid with a chain in the foreground, I lowered that onto the fire at 5 o'clock yesterday and scooped a couple of scoops of dirt from around our charcoal hearth on top then packed it into the crack around the edge well. We're supposed to let it cool for 2 days, I'll tip it onto a wire mesh screen and bag anything that looks like good cowboy charcoal. The rest will leave that black stain in the soil from a coaling that I've discovered in the woods several times. Kind of neat to happen upon one.
That's a Thansksgiving stumpkin in the background 

[69bronco]

I find there's a fine line between charcoal and ashes . Last batch I had some company show up and didn't cap it off on time, probably 20 minutes past usual. Poof!

[Bert]

I love making my own charcoal! Never did it on that scale though. Usually a metal 5 gal bucket at a time. Good Luck!

[samandothers]

Look forward to your picture of your creation!

[gww]

I have been looking for a good 30 gal barrel to fill and turn up side down in a 50 gal barrel.  I have found one of two but they always have a rust hole of some other defect.  I have not gone out of my way or wanted to spend any money getting one but will keep looking and when I finally get one, it will be time to try it.  Interested to hear your final out come.
Cheers
gww

[TKehl]

GWW, if you get around Sedalia, I'll give you a 50 gallon barrel.  Closed head, but good shape, still have paint on them.  They throw them out at work and I often have more than I need.

FYI, there is a good article about firing a LARGE charcoal kiln in one of the Foxfire books.  Can't recall which one...

[gww]

TKehl
Thanks for the offer.  I took the 50 gal barrel I had and cut the top out for storing chicken feed mouse proof.  I do have another one that I can get at moms house and so I am good.  If a guy could only see into the future.  I had a thirty gal barrel with a spicket on it that I had kerosine in and gave to my brother in law who ended up giving it to some one else.  I had another one in my shed full of trash but the bottom rusted out and another one at moms used as a trash can with the same results.  Now when I want one, I have ruined them all or already given them away.  I can't see spending much untill I try it myself and see if it really works for me. 

That was a great offer but I think I am good there and sooner or later I will come up with something.  I saw one guy making it in gal paint cans and oven roasting pans in his wood stove.  I have a wood stove but don't feel like making such small amounts.  Them guys make fire works and filters and such.  Me, I just want to use some of the stuff I am just burning now to cook with.  super small batches don't have much appeal to me. 

Again, your offer was nice.
Thanks
gww

[thecfarm]

I was looking for one to burn stumps. I heard someone say they have a $50 deposit on them.     Maybe that is why I can't found any. I've been watching one at a woods landing. I got one from the dump,but I would like to have another one,since they are hard to find.

[69bronco]

I was looking for one to burn stumps. I heard someone say they have a $50 deposit on them.     Maybe that is why I can't found any. I've been watching one at a woods landing. I got one from the dump,but I would like to have another one,since they are hard to find.

I've got 15 or 20 55gal drums, if you get over my way I'll load you up.

[thecfarm]

Deal!!   

[Don P]

Probably only if Sam needs one, this is the old road parallel to I-77 running up the escarpment between NC and VA. Highway 52 through Cana, VA has the removable lid kind at the apple/honey roadside stands. That is really a nothing bigger than a pickup truck with good brakes hiway , there's country songs about that hill, several

So I pull in to one of the stands to buy a drum, he really wants to sell 2, the second for half price, I should have done it, a man always needs another drum. So we walk by the pile of drums marked honey, some south American stamp, and I go inside to pay, stacks of jars of mountain honey inside. Now ... I had walked by this stack of foreign honey drums on the way in to the store 

[LeeB]

They have mountains in South America. 

[Don P]

I realized if folks were going to be milling around I didn't want to dump out 500 gallons of charcoal. I need to load Christmas trees tomorrow so might not be able to see if we made charcoal for a few days.

We did light the stumpkin around dusk tonight though.


This one was a little later, it was kind of a neat abstract;

[samandothers]

I have been up and down that road a time or two going from Winston Salem to the Blue Ridge Parkway particularly before the connector was put in between I77 and 52 south of Mt Airy.  It is an interesting drive.  We would usually hit the Parkway at the top of the 52 climb and go North.

By the way the Stumpkin is neat!

[Don P]

Yeah, those stumpkins are a neat use for a hollow log. This one didn't get up and go that good. I've had it stood on its end for... years. It should have had a piece of tin over the top. It seemed to be a little too damp for quite awhile. Five year old Matthew built and ran that little bonfire at the bottom intake. Tending that and the fire coming through a crack in the back kept him entertained all evening.

I shoveled out and bagged 16 30 gallon trash bags of charcoal today. With a better burn it should make about 20 bags worth BUT I need to screen out a lot more. This screen is leaving too small pieces still, I think I'll try some chicken wire which will dump probably 50% into the next grade, which would be good blacksmith or metalwork size I think, then what drops out of the screen in the pic is good bio-char for soil. I got 2 bags worth of it. I did some reading, it looks like the soil would be happy with 10-20 tons/ac, so no worries about a spill  .

I forgot to take a pic when I tipped it over, I'm about halfway into it. You can see we didn't do a good job separating sizes so there are a lot of "brands", unburned chunks, that got pulled out and will go back in next time.


Then the screen and into bags. This all needs to be a stand that I can bobcat around that grades 3 ways and it shakes down into the sacks. I need to get some of those double wall paper sacks. Anyhow, there's the charcoal empire, low startup costs   

[drobertson]

Never done it on purpose, but have noticed larger slab burn piles contained nice charcoal when the burn settled.  I know for a fact the makers of it use dried wood, light , burn then choke,(damp) off the O2, making lump, doing your own makes sense to me, the timing of the water quench is a key component,

[Don P]

There's no water quench here. I stick a fork, darn, I just looked back at the pic I posted, the lid is upside down. You can about see the bolts that hold the 4' or so of chain on the other, top, side. I bump the barrel and drop everything below the rim, slip a fork under the chain and drop the lid in the burning barrel. Get it punched down level and then scoop dirt on top till it seals all the smoke out. It's amazing, that 500 gallon barrel was cooling rapidly in a half hour.

So today's burn started with the barrel on its side shoved over right beside the slab pile, duh huh. I stuck in slabs, nicely lined up, no big gaps from tossing them in over the top of an upright 7' barrel. Chainsawed the pile somewhat close to the top and tipped it up. Shoved it back over to the burn area and stuck the torch in the hole. It really needs 3 or 4 bottom ports to get going, oxygen never gets to that bottom back corner. I let it get going longer before I plugged the bottom hole. from then on it burns up top but no oxygen gets to the bottom and it begins cooling. I opened it for about a half hour around 2 hours into the burn and warmed the bottom back up, who knows  .

With it pretty well packed it dawned on me charcoal really isn't that much smaller than shrunken wood. I thumped the barrel several more times and did add a good bit more but I dropped the top on it after about 4 hours.

This is lighting it with a weedburner torch stuck in the single 4" hole.


And the action shot, I've bumped it once and piled more on, I capped the bottom inlet soon after this;

[Don P]

I need to get more uniform bottom air, it's just not getting a good burn in the bottom of that big drum. The top of that last burn was great charcoal but in that tight stuff down below not enough air in the early burn to get it going, the bottom half of the barrel will need reburning but not before I cut another hole or two around the bottom that will get it going then I'll block and dirt pack those shut once its rolling and smoke free.

I screened into 3 sizes this time by using a chicken wire screen first blocked up over a 1/4" mesh expanded metal screen. 1" and larger pieces of charcoal on top of the chicken wire goes into lump charcoal sacks. Sitting on the next screen is 3/8 to 1" foundry grade, then everything that drops through is biochar... the greatest interest right now is in biochar, I could grind and sell every bit.

We were under wind warnings today. I went down to work in the shop but had a squirrel attack.  My first charcoal melt, this chunk of aluminum is about 6" across and 1/2" thick, the mold was the bottom of a large coffee can.

I just nestled a cut off empty propane little camping cylinder into a 5 gallon metal pail full of charcoal, popped a 2" hole in the bottom edge and hooked an old vacuum blower to it. This was as crude as it gets, an uninsulated furnace, winds to 50 blowing blizzard at times and it melted metal, neat! On the second batch I had a good bit more in the crucible, enough where I was starting to be able to just push scrap down into the pool and it would melt. I skimmed the dross off the top, got my stuff ready to pour, opened the top back up... and the metal was gone! It's all in the bottom of the pail, I had probably too much air and really had a torch going on that thin little tank. I'll rig it up better but I had a... blast 

[btulloh]

What are you using for your crucible?

[Don P]

It was on old empty camping propane cylinder with the top hacksawed off. So much too thin but it was sitting there  . I'll be in town tomorrow and will pick up a nipple of 4" sch 40 black pipe and an end cap and try that. I'll also see if I can get a bag or two of fireclay and some sand.

I've been emailing around with some interested local folks thoughts as I've been playing, it might be of interest;

Well I couldn't screen in the wind yesterday so I played with some of the mid sized charcoal, between grilling size and biochar sized. I slapped together a furnace in a 5 gallon metal pail and put a blower on it for forced draft, basically a deep bed of charcoal and a blacksmiths forge. Nestled in the charcoal was an old camping propane bottle with the top cut off for a crucible. In the crucible I put scrap aluminum. Attached is a pic of the first pour, I just poured it into a 2 lb coffee can and made about a 1 lb disc.

The furnace was still working so I melted a good bit more the second time, I increased the charcoal and draft and got the pool hot enough I could just feed metal into the hot pool and it would melt immediately, pretty cool! I had just skimmed the dross off the top and was getting ready to pour and my metal disappeared from the crucible... I burned a hole in the thin steel propane cylinder However this is another use for our charcoal, we can release that carbon back to the atmosphere... and cast metal.

I now had a problem in the bottom of my "furnace" I had a slaggy mix of aluminum and charcoal. To clean that up and recover the aluminum for another melt I kept blowing air on the charcoal bed until it was gone leaving me with mostly aluminum that I'll remelt in another pour.

Sooo, where did that charcoal go? I combined the charcoal, pure carbon that the tree had created by pulling CO2 out of the air, with oxygen, and released it back to the atmosphere as CO2 and CO. Making and using charcoal while explaining this would be a real hands on teaching moment. There is the other lesson... if you smell burning fur, its you! All this stuff is wickedly hot.

In the screening from Monday I got a couple more bags of biochar. This would be the equivalent of "extra virgin" biochar by which I mean everything that drops through the screen is in those bags, charcoal AND ash. Ash contains the minerals that were in the wood, potassium (potash), it also has a liming effect. This is fine for most of us but this is not neutral biochar. Overdoing that... probably not really possible in a field but quite possible in a pot or small garden, could lead to ph or nutrient problems.

Any charcoal from above that screen is pure carbon, the ash dropped out of those screens. I will probably end up grinding that for biochar, that is nutrient free and should be ph neutral. So I'm actually producing 2 different kinds of biochar.

Oh, if you visit the old iron furnace at Foster Falls there is a large slaggy chunk of ore, charcoal, limestone and iron laying beside the furnace. At some point in the life of that furnace they lost blast and the charge inside the furnace "froze". I can only surmise they had to disassemble the front of that furnace and drag it out to where it sits now, then rebuild the furnace, a really bad day! I've scooted inside the Ravens cliff furnace, the firebrick lining inside of it collapsed, ending its service life.