The fumes coming off PCB boards during Pyrolysis are flammable, during the world war when uel was rationed the gas produced from a gasifier was used to operate bus's, tractors and automobiles.
Coal gas
Charcoal.
The residue ( ASH ) left behind after Pyrolysis is what your after.
Here's a report paid for by Uncle Sam.
This handbook has been prepared by the Solar Energy Research Institute under the U.S.
Department of Energy Solar Technical Information Program. It is intended as a guide to the design, testing, operation, and manufacture of small-scale [less than 200 kW(270 hp)] gasifiers. A great deal of the information will be useful for all levels of biomass gasification.
The handbook is meant to be a practical guide to gasifier systems, and a minimum
amount of space is devoted to questions of more theoretical interest.
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