[Stoves] Chimneys, rice husks [Ovens]

[ajheggie at gmail.com]

[Default] On Sat, 15 Jun 2013 17:44:56 +1000,Stephen Joseph
<joey.stephen at gmail.com> wrote:

>There has been a lot of work done on formation of crystobalite.  The rate
>of formation is both a function of time and temerature
>
>If you have low temperatures (450c) and short times (<60 minutes)you wont
>produce it.

Fly ash from wood boilers has always been considered hazardous in UK,
typically wood ash is 50% silica, I think, so rice is only different
in having a higher ash content.

The period that any fuel is exposed to the pyrolysis front of a tlud
burn must only be a few minutes but the char above will be subject to
the offgas temperature for the remainder of the burn.

Even so as has been pointed out the bulk of the silica will remain in
the char matrix.

I'm interested to see a bit more analysis of the "grey" particulates
Dean mentioned but overall it doesn't seem to be a big part of the
health problem when one considers how hotspots of silicosis have been
flagged up in industry.

AJH