[Stoves] personal pollution monitors (Andrew)

[Andrew Heggie]

On 26 December 2016 at 13:36, Crispin Pemberton-Pigott
<crispinpigott at outlook.com> wrote:
> Dear Andrew
>
> Was the ash content considered to be an important factor in the level of particles emitted, the total mass per ton burned?

No I doubt it, it was likely more to do with  the  propensity for
slagging in power stations, on the domestic from the temperatures
would not have been high enough for it to become significant.
>
> When looking into what ambient air contains, the sources like power stations and fireplaces have very different profiles. In general:  Homes produce PIC's and power stations produce flyash. Ho‎mes produce PM related to the quality of the burn. Big burners produce things that are inherent in the fuel because the quality of the burn is very high and constantly adjusted.
>
> You get my drift?‎

Yes, I imagine smaller fires simply don't reach the temperatures to
burn out the "black carbon" particulates, also because they don't
have cyclonic combustors with fans to mix the powdered fuel and air
there is less fly ash.


>So if the ash was considered to be a major 'cause' of PM it is understandable, but is really a statement of something like, "Our burners produce a lot of flyash and rather than fixing them, let's limit the ash content of the fuel input."

My take was the slagging problem but the other thing is  big exporters
don't want to ship mineral content and its also loss of nutrient to
the soil. When I have seen these energy crops being harvested with
processing machines they set the knifes to strip the bark as well as
branches, so these parts containing the mineral wealth of the soil are
largely left to rot back in, thus exporting only the white wood for
conversion to pellets.

It's only a guess because I had to take a job elswhere 8 years ago as
small woodlands in SE England became non commercial.
>
> My second question is, has the price of the small diameter material been depressed by the regulation? Can it be used as a domestic pellet? The PM might drop a lot by changing the airflow speed.

It was an (off my original topic) anecdote to illustrate how standards
get adopted and have an unforeseen affect rather than anything about
particulates. Now one can only buy premium pellets that achieve the
standard, it isn't worth making pellets that don't meet the standard
so the knock on effect worked against what I wanted to do.



Andrew