[Stoves] Grates and chimneys

[ajheggie at gmail.com]

On Thu, 16 Feb 2012 22:59:37 -0500, Crispin Pemberton-Pigott wrote:

>BTW that is a remarkably high MC for spruce. Wow. We never see that. Is it
>from a swamp??

Taking figures from "the forest mensuration handbook" of about 1975
vintage grand fir at 200%mc dwb is the highest and by my calculation
that's only 30% dry matter on a wwb. Sitka is 164% and Norway spruce
183%. Poplar figure is from memory when we tested our commercial
dryer. Figures for fresh whole tree chips are worse in evergreens
because the needles have a higher mc. We often have trouble meeting
the 45% mc wwb requirement for whole tree pine chips delivered to a
power station.

I have a woodchip stoker designed to run on joinery waste and that's
nigh on impossible to get hot enough to burn fresh woodchip cleanly,
I'm working on that.

AJH