[Stoves] Charcoal & Stoves

[AJH]

On Wed, 11 Apr 2007 08:58:07 -0400, Crispin Pemberton-Pigott wrote:

>Dear Andrew
>
>>First step is to establish the moisture content of the coconut husk,
>>is it the same as what's called coire?
>
>It can be rapidly dried because it has a huge surface area per Kg.  

I was rather after what the moisture content was to get a handle on
why the offgas wouldn't burn.

>It is however a pretty smokey fuel. It must have a lot of resins that boil 
>off at a low temperature.  If the preheat is 150 degrees or so I found it 
>makes a clean flame but not without preheat, whether that was because of 
>moisture in it (probably not) or because it is volatile well below the flame 
>temperature.

If it's not the moisture content then there must be some other reason
the offgas won't burn, still as you say it will burn with some pre
heat then there is a means.

>gave me pause to consider that perhaps charring something this full of 
>resins is not such a good idea.  There would be big losses during the 
>process and if the gases were not burned it would leave a) nearly no mass of 
>charcoal dust and b) no useful work done.

You say there "would" be yet we don't know yet, if it is such an
abundant resource it must bear some further investigation, take note
of the point Richard makes, blending in some char may add sufficient
support to enable clean burning, remember unburnt smoke is lost
energy.

I must have lost my touch because I assembled a tlud burner from 2
spun steel 40cm by 150mm pipes and 4 bits of wire today. I filled it
with  40cm long  corrugated cardboard (573 grammes) and rolled around
a 40cm long length of scaffold tube. Initial results were good and but
the fire reached the bottom unevenly and the result was some ash in
the centre and of course once it began this bottom up burn there was
blue smoke. Anyway after I snuffed the remains I weighed 27 grammes of
scorched cardboard from the outside and 114 grammes of char that
itself didn't burn very well in a further experiment.


AJH