Thank you for the input. Very interesting project with your 7th graders, I am actually speaking to a couple of 7th and 8th grade classes next week about this material. Do you have any advice on that? I have been trying to get creative with my powerpoints and teachings aids, I do not want to lose the student's interest, and I also do not want the material to be over their heads.
When I fired this kiln up the other day, it burned very clean, you could not see and smoke coming out of the chimney, but, none of the biomass inside the retort charred (I think its because I was using stainless steel, which is very heat resistant). If the material did char I was thinking that the pyrolysis gasses would just flare off in the chamber, but I eventually do want to re-route those gasses to be burned off at the start of the J-tube. The chimney you see is just connected to the 55 gallon barrel, the bottom of that barrel is completely cut out and placed over the smaller keg (pictured above). It is kind of a closed system. Ideally, the chimney has the same area as the portion of the rocket stove where wood is loaded to be burned. As heat rises through the chimney it creates a... siphon I guess is one way to put it, a push/pull type motion with the air flow, that is the idea anyways. The heat travels around the smaller keg that is used at the retort. Hope that makes sense?