I made this video last year and thought I'd share it here. We've been working with this system for a few years now, and have generated a large amount of very high quality charcoal while heating our home. Feels like a very effective way to create a continual flow of charcoal while using the heat effectively.
Would love to hear notes and ideas from folks!
Hi Sean, I shared this same video of your last year . I follow this process to make char and love it.
I started with a thin SS soup pan but after about 40 cycles it has developed holes in the bottom. It still worked but was on its last legs so I upgraded to a steam table pan (or hotel pan). Mine is smaller than yours, probably 6" wide by 6" tall and 12" long. I think our stove is a bit bigger than yours but I'm happy leaving the extra space for the rest of the fire.
Mine will burn down to char in about 90 minutes. I've found that it still keeps oxygen out even if the lid is propped open 1/4" or so on some taller chunks of wood. As it off-gasses the wood shrinks and the lid settles down into place. Our main fuel source is pallet slats that failed to be removed in one nice piece for pallet projects. I set the chop saw up for 5.5" cuts and the pieces will stand up in the retort and fill it up efficiently.
When you put it outside on a cement slab, don't take the lid off to "cool it down faster". That introduces oxygen and it will slowly build back up into a fire.
If you pull it out of a hot fire, get it outside promptly because it can still be giving off some stinky fumes. We usually just do one batch a day and pull the retort out of a cold fire in the morning so there aren't any fumes.
"Hundreds of years from now it will not matter what my bank account was, the sort of house I lived in or the type of car I drove... But the world may be different because I did something so bafflingly crazy that it becomes a tourist destination"
Nice video. The pans are a great way for using up scraps. I just harvest coals for my gasifiers and biochar the dust. I used to use containers but they wear out with time. Nice clean efficient setup. Here is my much messier rig. https://m.youtube.com/watch?v=LKZPTBA-boU Best regards, David Baillie
I'm very new to biochar. Just wondering if I can use the regular charcoal I find in my wood stove in the mornings after it cools? Obviously the quantity is a lot less, but is this just the same kind of stuff?
Wood pyrolized in a very low oxygen environment tends to by almost crystalline. It has a 'ring' or a 'tinkle' to it when shifted around and is very light weight. If that's the sort of charcoal you are getting, then, it will work! But if you are getting lumpy, smudgy bits of dull sounding char, that is less than good.
I use a paint-can, with a few small holes punched in the top, full of wood shards and chips during a regular burn in my wood-stove. I place the can on the ash, turn the can upside-down so it can off-gas, but not take in oxygen, and make a morning fir as per usual. It gives high quality charcoal with almost no extra work.
The higher quality charcoal has a fractal-like physical structure, giving acres of effective surface area for micro organisms to inhabit. Low quality char has a more sponge like structure and orders of magnitude less surface area.
Once you inoculate that charcoal with biological organisms, it becomes biochar.
I find that "tinkly char" can also be made in an actively managed open burn pit, though there is more ash content. It may not be as good, but I make wheelbarrows full at a time, so maybe that compensates a little. It's great to add stable carbon to soil, for many reasons.
Looking at Sean's excellent and well-considered video, I'm taken down memory lane, and realize how much I miss my old wood stove.
He baked a muffin that stole my car! And this tiny ad: