Here's an album of pictures from the first burn of the Oregon Kiln that took place at Willow Witt Ranch on Nov 27, 2015. Thanks to Suzanne and Lanita of Willow Witt Ranch and helper Micah. Thanks also to Vicklund & Son for fabricating the kilns and mounting the jib crane to the trailer. The Oregon Kiln was designed by Kelpie Wilson, Wilson Biochar Associates (wilsonbiochar.com). The Oregon Kiln is a Flame Cap Biochar Kiln intended for use with forest slash and other kinds of waste wood commonly found in the forested regions of Oregon and elsewhere.
Web Album: https://goo.gl/photos/H1bBQ1mZQwukipAp9
I was impressed with the efficiency of the kiln. We had some big chunks - 4"x4" and even a little bigger that charred nicely. And it did not take all day. I showed up at 10 am and we lit the rick at about 11 am. Quenched at around 5 pm. So the burn was only 6 hours long. Compare to my 4 foot diameter, 4 foot tall tube kiln that took 11 hours to fill. Total volume is almost the same. The Oregon kiln dimensions are 4' square bottom base, 5' square top base and about 25" elevation (sides are 26" wide).
Here is a simple description of how the kiln works:
You have to think of the Flame Cap Kiln as a retort that is made of steel on the bottom and of a stable gas vortex (actually a collection of vortices) on the top. Both function to exclude air, hold in heat, and char the feedstock.
Next task is to design some better wind screens - I'm thinking of something modular that can be moved around the kiln as needed.