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[juzer]

Hey,
My name is Juzer and i am working on a problem of evaluating the losses effectively in a boiler.
I have come across the case of solid fuels, where indirect efficiency calculation is proving difficult.
I have a theory that in case of coal with large number of fine particles( around 30% particles of size < 2 micrometer) the draft can carry off the particles with it also they cna fall through the grate. So I am trying to apply a mass balance and element balance to find out this quantity.
Details of the mass balance:
Mfuel + Mair = Mbottomash + Mfluegases + Munburntfuel.
to get flue gas masses ill be evaluating the flow rates of flue gases using anemometer, then invoking ideal gas law to convert volume fractions to mole fractions. Also i'll assume NOx formation is negligible and unburnt solid fuel volume is negligible.
The aim is to get the unburnt solid fuel quantity
A few concerns i have:
1. Some of the solid fuel may burn along the way in the flue pipe before it reaches my flue gas analyser.
2. some of the solid fuel may fall through the grate as it is fine, but will be clubbed with bottom ash.
Could the forum please tell me about possible shortcomings of this method. Please be critical.

To crosscheck ill be using an element balance
using this equation(ignoring NOx and H2)
CxHyOz + a*(1+E.A.)O2 ----> bCo2 + cCO + dH2O + eO2 + fC
then applying elembent balance
y= 2d
z+2a(1+EA) = 2b +c +d + 2e
here d is known
and b:c:e is known. Hence we can get result
only problem is i dont know how from ultimate analysis (without molecular mass) i can get formula
then ill apply carbon balance to get unburnt carbon
x = b + c +f
Thanks for Reading
Juzer