Ok here is a concept Ive been carrying around in my head for quite a few years.
The idea of this, is for use as a primary heat source using standard cut and split firewood while rendering charcoal as a byproduct. So in concept during a first light up it will run in a bypass updraft mode. Just like most ordinary wood stoves. So you fill it up and get it going until its good and warmed up. Then you switch off the bypass gate it runs in a downdraft mode. Bellow the primary air input is a set of rods with fingers. Sort of like a rebok chunker but instead of blades there are finger the poke into the char logs and chunks to break them up into small pieces. From here these pieces then fall down into an auger troft. There are three bars that span across this troft and spread 4 inches apart. So larger pieces that make it through the buster, will further be broken down as the auger tries to push them past these bars.
Primary combustion gas also passes through the buster mechanism, but right after it is redirected updraft and too the outside walls of the burn chamber. Second stage air is introduce immediately after this transition so the ambers and established combustion will keep it lit. Fire brick will be used on the outside housing of this passage chamber. Once the gas enters the top is then directed to a heat reclaim with a forced air blower to direct heat out of the unit. This will have a backside exhaust outlet so it is more universal you can go through wall or through the roof.
Dealing with the charcoal indoors I think is a no go. So this will have an auger drag out that will take the char out through wall to an outdoor barrel drum container with a sealed lid.
I have no idea if this will work at all lol. But ideally I will be able to control how much char it produces verses how much heat is produces. For instance during the day I may run optimized for charcoal production, but at night I will want a full nights sleep. So this thing will need to still be burning in the morning. I think if I control the buster speed to a crawl or even stop it, then it will act as a static grate and the fuel will burn to ash. No biggy the auger will pull it out. You will still need to screen the fuel so ash isnt a worry.
Ill post more detailed pics later, Ive been working on this from the time I woke up till right now.