biochar burner

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Dec 12, 2002
Since moving, have a lot of cardboard waste, and there's general weeds and twigs that are dried. Posted last year about the terrafoming that took place in the South American cultures with Terra Preta, and have been trying to make my own biochar Here's my most successful design...on cardboard. Works fine on twigs and (dry) pine needles Up close, you can look down within and see the smoke produced by the fuel, and then the particles burn out when the upper air holes let the air back in to reburn the smoke. At about 2:00 clock position, you can see the combustion taking place as the air gets reintroduced to the smoke.
End result, with a few big bits to throw back in. But quite a lot of char. compared to straight burning stuff. Char will still be in the garden a couple of centuries from now versus compost. Wikie Terra Preta
Just read the Wikipedia thread... and it’s early so bear with me: If I read this correctly, the Biochar creates or introduces organic matter into the soil...but as only a charcoal, the result of burning, how is it that the Biochar introduces a microherd into the soil? I can’t imagine anything being left after the burn.... Or... Does it simply allow for better air/water infiltration to more readily accept a microherd? .... this is good stuff by the way. Very interesting topic
Finz, the char is (obviously) sterile at the point that it is made. But it is there (comparatively) forever. It has large surface area for things to live on, while still being essentially inert. It provides hosting sites for micro flora, as you have picked up.
2nd cup of coffee... the fog is lifting Acts as soil amendment similar to compost. The difference being: 1: remains as a soil amendment indefinitely unlike compost which, due to its high OM content which is readily absorbed by the soil structure 2: unlike compost, which, of and by itself introduces OM and some nutrients to the soil, Biochar simply remains in the soil acting as a medium to allow for better air infiltration as well as acting as a “sponge” for absorption of nutrients and water. 3. I imagine that Biochar must be dug/scratched into the soil vs applying as a top dressing...? Am I getting close? By virtue of charring, would this have a consistently lower pH than compost which is dependent upon the material used?
Originally Posted By: Shannow
Finz, the char is (obviously) sterile at the point that it is made. But it is there (comparatively) forever. It has large surface area for things to live on, while still being essentially inert. It provides hosting sites for micro flora, as you have picked up.
Hosting.... that’s the word. Ok
What works really good is wood chippings from tree services. It is used as muclch and never mixed into the dirt. An old timer showed me this years ago and it works . The chippings breaks doun and releases minerals and N,P an P into the soil in a way plants like. Wood ash is full of minerals as well.
I burn all our paper and cardboard waste, and tree prunnings too big to mulch...and the Xmas tree. All ash goes on the garden. I figure ash is minerals, plants need that, the charcoal is good too I thought...maybe I was right. My soil is sandy, no nutrients, so my garden soil is all man made, and by the look of the plants is pretty good. I use an incinerator made from a washing machine bowl, sitting on an old display stand, burns really well and easy to empty and clean. I burnt a lot of prunings yesterday, and the thick bottom part of the Xmas tree...letting it slow burn, I had a look later, and a piece of log was sitting over the centre pipe, air coming up was cutting a hole in it. Lots of air gets into this thing, burns well. Lots of ash, but lots of charcoal too. OMG !!!! Is that an oil filter in there ? !!! More fuel for the flame, contained in a oil in my ash.
"Compost" stays in the soil infinitely unless the soil is sterilized. The carbon/nitrogen/fungus/bacteria contributions of compost should be recycled locally and beyond for eternity by the soil biome unless interrupted. Not that I am downplaying the biochar because it is a great addition for sure. I just can't let you degenerates keep bad mouthing compost without speaking up on behalf of that black gold. If it keeps material out of landfills and makes use of it, I can get behind it thumbsup
The "terraces" are all sand and gravel, to allow free drainage ang prevent my garage and slab from sliding down into the house. Here's some plants that I've grown from seed since moving 15 months ago. Clary sage, Yarrow, Hyssop, and Rue in order of appearance...the yellow rose I moved from another area on the block, into another space prepared with Shannow's "terra preta" cardboard charcoal, moved it in winter, and it's come along great this summer. The stuff still free drains, and the plants love it.



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