We have talked and speculated a lot about whether air curtain incinerators can make biochar. Today I saw it in action on a Forest Service field trip in the Ashland Watershed. Air Burners are disposing of large landing piles of green slash mixed with plenty of dirt. Turns out the moisture and dirt prevent the powerful blower from getting to air to every part of the burner, creating perfect conditions for making biochar!
See pictures here:
Here are some pictures of one site that is finished. The biochar has been mixed into the soil and trees planted. It looks really nice.