Farm Charcoal

Wasn’t exactly sure where to post this as it falls into so many categories.

Farm Charcoal

I make charcoal from time to time to sell at the farmers market, with the economy so bad of late, sells haven’t been booming. Also, brazilian lump charcoal is dirt cheap, (despite questionable origin). The real money is in smoking woods cut to the same size as raw charcoal. Charcoal became the appetizer.

Charcoal has lots of other uses on a farm. Need to bend or shape metal in your forge? I find it indispensable for water filtration. It has medicinal uses and let’s not forget pyrotechnics.

Now don’t go thinking I cut down trees willy-nilly. I lose trees every year to wind and storms and especially to drought the last few years.

Any high quality hardwood makes great charcoal, various oaks, hickory’s, even maple. The properties of each vary greatly. As far as I’m concerned red oak is the king! It comes out extremely cracked and pitted. When it comes to ease of lighting, burning and water filtration I’ve found nothing to compare.

In a nut shell – Small pieces of hardwood, 1.5 X 1.5 X 5 inches long go into a 15 gallon steel drum. This small drum is placed into a 55 gallon steel drum, scrap wood is placed into the gap in between the sides and burned.

People always get hung up in the details but the concept of using a retort is the important part. Use any type of containment vessels you can dream up or build! As long as age old principles are followed anyone can make great charcoal!

The retort or small drum can be thought of as a static chamber. Being filled with wood it has very little oxygenated air to begin with, it’s soon gone as the result of a flash burn. For the rest of the cooking process there is no oxygen left inside for fire. Result, this good hardwood “cooks” into charcoal. Exiting gases don’t burn until they reach oxygen outside the retort.

Details

The best detailed version of the whole process I’ve written so far is at survival blog dot com. I believe it was posted on Sept 19th 2012. Under the name Dan L. There are no photo’s there.

On Aug 14th I posted an old version with photo’s in the Green Deane Forum. “Eat the Weeds”. It’s under primitive skills, Making Charcoal. I answered a few questions already.

Here are a full set of photo’s with a few notes. I hope it helps any and all who read it!


FC 01 – Stacked red oak disc’s ready for processing. Some hickory to the left and maple in the background. I experimented quite a bit that first year.

FC 02 & 03 – Some knotty hickory that didn’t split very well. Loading the retort is next. The pieces in the retort are a little large for efficient processing.

FC 04 – Scrap pine I got from a local wood products company. Gave the owner a couple of bags of charcoal and he was more than happy to let me have all I needed. Quick burning pine is helpful in regulating the cooking process but white oak fire wood from last year is the main stay.

FC 05 – I run 2 cookers at the same time spaced about 3ft apart. They share radiant heat which cuts down on the total amount of scrap burned. I can produce about 35lbs of charcoal a day. 17 – 18 pounds per cooker.

FC 06 – About three pounds of the finished product. Notice the aloe in the background? If you cook charcoal you’re going to need some.

FC 07 – 1 of 3 vents cut into bottom edge of large barrel.

FC 08 – Vent holes in the retort.

FC 09 – A cooker set, 15 gallon drum with crimp on lid inside open head 55 gallon drum.

Next 3

Last 3

thank you for sharing the details and the nice pictures. I'd like to experiment with making charcoal over the winter/rainy season here. I have loads of white oak, madrone, doug-fir and ponderosa pine to play with. Have you tried making bigger pieces of charcoal in the 15 gal drum (not breaking up the wood prior to the burn)? I may try using a sand-pit to transform some logs into charcoal to see how it works...

hey dave, I would be curious to see your water filter set up. Do you further process your filter charcoal with steam as your cooking it, and if so, will it stay in large chunks?

I've had thoughts of simply filling a 4" plastic pipe with hardwood charcoal, (coarse pieces like in your pix FC 06) adapt my 1" city water supply line to the 4" 'charcoal filled filter line', (then reduce to 1" again, install a cartrige filter to catch the fines as it gets to the house). I figure just leave the stuff in there for 20 years or so. Am I way off base?

james beam

I have seen burn chambers similar to yours. The main difference is that they have 2 pipes coming out of the top of the inner chamber that are open ended near the bottom of the outer chamber. These take the off gassing product from the smaller chamber, and feed it to the burn chamber. This helps to fuel the fire, as well as keeping the off-gasses from the atmosphere. A more complete burn of the fuel.

Quote
"I'd like to experiment with making charcoal over the winter/rainy season here."


With this method ambient air temperature is a factor. The cooler it is the more scrap wood is necessary to “cook a batch”. More work for the same return.

I’ve only used hardwoods for charcoal, have no experience with pine or fir.

I started out with bigger pieces. Cooking time was much longer compared to the size I eventually settled on. This allowed me to make sellable amounts in a shorter time.

Besides, for cooking on smaller charcoal grills and green egg’s the smaller pieces work out better.

I know it seems like a lot of work and time to prep small pieces of wood, in the beginning it was. After a couple of hundred pounds I was amazed how quickly it could actually be done AND keep all my fingers! This is why straight grained wood is important, easy to spilt. I could prep enough to fill both small drums in a little over an hour.


Quote
"I figure just leave the stuff in there for 20 years or so"


My family has used the same spring for water over 80 years, no need for filtration. Customers at the farmers market reported back the results and preferences. Friends and I experimented with gravity systems of various sizes. The goal was to filter water for a few or a dozen people in emergency situations. The 25 gallon tub’s I buy cattle feed in work great, 5 gallon buckets too.

Locally deposits of white quartz sands are plentiful, great to layer above and below the charcoal.

Charcoal for filters, the goal is surface area. You crush the charcoal in fine pieces exposing more surface area to come into contact with water. There are lots of better expiations on the net.

I’ve read various “authoritative statements” over the years. Basically 20 to 40 pounds of charcoal will purify water for 1 person for a year. Of course this all depends on how polluted the water is to begin with. Charcoal can only absorb/trap so much pollution.

In searching for a way to test when homemade charcoal needed to be replaced I settled on chlorine. Occasionally run a batch of “chlorinated drinking water” through the filter. When you start tasting the chlorine replace the charcoal! Anyway, this was the best test I could come up with.

Basically the same as knowing when to replace purchased filters in home systems. If the water tastes like crap replace the filter!

Quote
"The main difference is that they have 2 pipes coming out of the top of the inner chamber that are open ended near the bottom of the outer chamber"


That’s, what happens here, the retort or small drum is vented in the bottom. As the escaping gases reach oxygen in the “burn chamber” they ignite. I can always tell when out gassing starts by the tremendous heat coming off the big barrel. I can sometimes see a color change near the bottom of the furnace drum which means temps are near or above 1100 degrees. Very efficient, without pipes.

sounds like a pretty good test too me! thanks dave for the informative response.

james beam