[Stoves] Charcoal & Stoves

[Crispin Pemberton-Pigott]

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.  Coir I 
think is technically the fibre which has been taken from husks that are 
first retted, often in the ocean for a few months, and combed out.  I guess 
the answer is no.

>It strikes me there's never going to be one best route for every
>waste, in a hot, dry climate Richard's retting and compaction makes a
>useful fuel from non woody agri waste.

Agreed.  I am not sure if the husk will ret (rett?) properly.  It might be 
fibrous enough to stick together on its own under modest pressure.  Perhaps 
he will comment.

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.

Your comment
>Charring does have a lot of advantages though, the
>normal criticisms of charcoal is its overall
>poor conversion and pollution during making plus
>risks from CO in use.

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.

>As we have seen there are a number of ways of making charcoal
>cleanly and using the waste heat.

So my present inclination is to suggest that a use for the gas heat should 
be found first and then the char treated as a waste product of that process, 
rather than the primary goal.  If indeed the heating value of the gas is 
high (how do I refer to that?) then perhaps a commercial application like a 
husk gasifying bakery would be the sort of place to start.  The temperatures 
involved would be low.  Perhaps I could try this in Chimoio, Mozambique.

Regards
Crispin