[What forum? I picked one, and you might think it is wrong. ]
Trying to search for this in a search engine one gets swamped with medical or agricultural incinerations of bodies (tissue, humans, animals, ...).
What a person is trying to burn in this incinerator, is diseased plant material And that burning might be best done in a couple of steps.
I really don't like the idea of using steel barrels for burning (my background is materials science and engineering). I like the idea of using "stone" for burning; it's already oxidized.
There is supposed to be a lot of expertice here on
rocket mass heaters, so let's see if we can bend this to accomplish what is needed. But for me, I think the best incinerator is something at the focal point of
solar mirror.
A particular demonstration of a
rocket mass heater had:
a vertical fuel area (fuel "flows" down)
a horizontal burn zone
a vertical chimney (where the smoke is burned)
a downdraft into a chamber which absorbs heat
an eventual outlet.
Some plant diseases may have you trying to destroy leaves or grasses, which are highly flammable when dry. Other plant diseases give you a dense piece of
wood (cellulose, lignin and hemicellulose) which is loaded with
water.
The plenum where a
rocket mass heater deposits heat to a thermal mass, is where I am proposing to load the material in the first step.
I am thinking one puts a thermal (reflective) shield around the "vertical column" where the smoke is burned, since we don't want to radiate any heat away until after it processes what is in the Stage 1 plenum (if anything).
I suspect this plenum is approximately constant area, it may be a labyrinth; in heating applications.
In Stage 1 incineration, we want the flow rate of hot gas at the "end" of the plenum to be very low, low
enough to keep leaf fragments from flowing out We probably want some kind of replaceable screen at the end of the plenum to stop possibly diseased material from leaving. The gas flowing through the plenum,
should have less oxygen than normal air, and should be hot. The killing of pathogens involves a time/temperature trade off. You can go for less time, it the temperature is higher. I am going to guess that on the long time exposure, you want something like 200C or 400F (not exactly the same, but close).
Similar to making charcoal, it is likely that the temperatures in the plenum will be high enough to drive many pyrolysis reactions. The material put into the Stage 1 plenum will become an approximation to charcoal. The exhaust from the plenum will be laden with gaseous fuel (and could resemble smoke). It needs to be fed into another
rocket mass heater to burn it (again).
The disease we are concerned with are bacterial and fungal (are their any viral or prion diseases of plants?). The pyrolysis gas from Stage 1 should not have disease producing components in it. It could be biochemically active, which is why it needs to be burned in a Stage 2
rocket mass heater. This pyrolysis gas should have much less "ash" content than the original material.
I am thinking, that much of the original load of diseased material to be incinerated, will be come an approximation to charcoal. And hence could be burned as fuel in the stage 2 rocket mass
oven. But if a person was trying to destroy things like diseased leaves, some of this charcoal could be very fine. It might be hard to reliably burn six 9's of it in a rocket mass heater.
If the "solids" from Stage 1 got enough time/'temperature exposure, they should be charcoal (aka
biochar) and could be just added to your
compost. But, how do we tell if they got enough time/temperature at heat? Which is why I am thinking it needs to be "burned" twice.
Just like an ordinary rocket mass heater, this creates heat. But the heat is "released" quite a bit differently. Is there some use for the "excess heat" in this process?
A friend pointed me to storing excess windmill
energy by making fertilizer. Is something along that line feasible here?
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