

Microwaves turn wood waste to high value carbon (2014) - edward
http://www.3news.co.nz/business/microwaves-turn-wood-waste-to-high-value-carbon-2014110216#axzz3aHZKWULr

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danieltillett
There is nothing magical about microwaves - they are just heating the wood to
a high temperature where the carbon chars. You can do the same using any form
of heat - the low tech and cheap solution is to use some of the waste wood to
generate the heat.

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SixSigma
Except they heat by increasing molecular dipole rotation which, while not
magic, is different to conduction. Which means the heat can penetrate more
efficiently.

[http://en.wikipedia.org/wiki/Dielectric_heating](http://en.wikipedia.org/wiki/Dielectric_heating)

I want to be convinced this is better than simply producing charcoal by
burning some wood to dry out other wood.

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danieltillett
Is heat penetration really an issue with making char from waste wood?

I have seen some very clever designs where the syngas generated by the
carbonisation process is used to provide the heat to carbonize the wood. With
this approach you can drive the whole process cheaply with a very low carbon
loss.

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SixSigma
That bit I don't know, hence my caveat.

What I was responding to is that microwave heating certainly is different to
other methods.

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danieltillett
In practice it is not that different to just rapid heating. The organic
chemists have been arguing about this for some time [1] and any non-heating
effect is very minor.

1\.
[http://pipeline.corante.com/archives/2013/07/09/a_microwave_...](http://pipeline.corante.com/archives/2013/07/09/a_microwave_argument.php)

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leoh
> But CarbonScape's coke is made from wood that has absorbed carbon as a tree,
> so no new carbon is released, and that's better for the environment.

This doesn't make sense. It's like saying: oil is made from organic matter
that had absorbed carbon as organisms, so it's good for the environment.

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ZeroGravitas
Oil made from recently dead organisms would be better for the environment, and
various schemes are proposed to make it.

Normal oil is bad because it's releasing carbon stored over a long time and
introducing that carbon back into the system.

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trimble-alum
Seriously, when will Bill Gates' team adapt this to drink the water from
microwaved ...

