Monday, July 16, 2007

pyrolysis

I have read a lot of comment of the role of pyrolysis and how it produces gases and liquids while leaving char behind. Obviously the higher the temperature the more complete the process that could well include substantial reforming of complex molecules into simpler compounds. This is well worth the trouble if the fuel and the end markets for the liquids, gases, heat, and char are located in the same industrial setting.

As soon as we lose any of that closeness for any component, we lose efficiency in a hurry. I say this because even if one has a market for the lighter components, then you will need to shift unto other components of the fuel in order to support the process. The point I am making is that a lot of the fuel gets used to produce process heat.

Agricultural charcoal is in the position of been located at the source and application sites of the process protocol. Thus all the light fractions and as much of the process heat as possible needs to be used in the process itself.

This will also turn out to be the best protocol for an industrial sized plant as well. The secondary gases and liquids are potentially a red herring that can generate poor design when the only thing that matters is burn efficiency.

The interesting question for the shipping container design is what might the net efficiency be? I ask this because it will be possible to avoid any combustion in the main chamber as an operating option. The 2000 degree exhaust gas from the second burner can bring the core temperature of the shipping container up to the needed 400 t0 500 degree level.

Yields of obviously inefficient and messy systems run around 20 percent. It may be thus possible to exceed this by an additional twenty percent . The theoretical 80 percent yield may even be possible if it turns out that the volatiles produce enough fuel to complete the job.

This is a major potential payoff for both agricultural charcoal yields and the direct sequestering of carbon, and well worth the small additional capital investment in a charcoaling system.


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