[Stoves] Ways of testing combustion/emissions

[Crispin Pemberton-Pigott]

Dear Frank

I am getting behind in my necessary replies to your interesting avenues of
research.

I agree in principle with the carbon calculation loop, which I do to check
the quality of the data.  You can do a O2 balance as well.

If it is not CO2, then it is more likely to be CO than anything else. I
think you need to bear that in mind.

Something else work considering is that usually the analysis of the fuel is
known.

This means that if there is 1% sulphur by weight, then the SO2 and H2S and
H2Sx should contain all of it, plus what is in the ash. So you see what I
mean?  If you wanted to know how much was in the ash, you can tell by
knowing what is in there in the first place, then subtracting what you can
measure. What is missing is in the ash.

You can also do this with Carbon. That is why I keep asking you for the
carbon content of things.  

What you will find is that the energy of the non-carbon components (save H2
is some cases) is so low it is not worth tracking. If you get measurements
accurate to 1% and the energy in the non-carbon oxidizable components is
0.5%, you won't even bother to worry about it.

It boils down to tracking the H2 and the C. In most cases you can assume the
H2 is burned, however I found that with coal this is not the case when the
combustion efficiency is really low. Prof Philip Lloyd feels high H2 levels
in coal smoke indicate evidence of a water shift reaction creating H2 and
CO. Barring that, you can assume the heat from hydrogen has been released.

I am becoming convinced, against my nature, that the energy in the
particulates is usually so low it is also not worth calculating.  The value
of tracking CO2, as Tami often reminds us, is that it is often done at a low
concentration and calculating it using the 'missing O2' method is inaccurate
at low CO2 concentrations.

I think tracking CH4 is OK, but you will probably find in a reasonable fire
there won't be much. It will emerge as H2O and CO or if things are better,
as CO2. It is much harder to light CO than CH4.

What do you think?

Regards
Crispin