10.1021/ef4018114.s001
Paula Teixeira
Paula
Teixeira
Helena Lopes
Helena
Lopes
Ibrahim Gulyurtlu
Ibrahim
Gulyurtlu
Nuno Lapa
Nuno
Lapa
Pedro Abelha
Pedro
Abelha
Slagging and Fouling during Coal and Biomass Cofiring:
Chemical Equilibrium Model Applied to FBC
American Chemical Society
2015
bed agglomeration phenomena
Biomass Cofiring
bottom zone
biomas
chemical composition
elutriation effects
occurrence
chemical fractionation
silica sand particles
wood pellets
combustion process
straw pellets
liquids salts
FBCA
Chemical Equilibrium Model Applied
fluidized bed monocombustion
nonreactive fraction
cocombustion effect
2015-12-17 00:14:43
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Slagging_and_Fouling_during_Coal_and_Biomass_Cofiring_Chemical_Equilibrium_Model_Applied_to_FBC/2027673
A thermodynamic model was applied
to foresee the occurrence of
fouling, slagging, and bed agglomeration phenomena during fluidized
bed monocombustion of three different types of biomass, namely straw
pellets, olive cake, and wood pellets. The cocombustion effect in
reducing the occurrence of deposits and agglomerates of blends of
5, 15, and 25% (wt.) biomass with coal was also assessed. Chemical
fractionation was applied to evaluate the reactive and nonreactive
fraction of elements in the fuels, which was used to estimate their
partition between the freeboard and bottom zone of the boiler. Qualitative
and semiquantitative analytical techniques, namely, X-ray diffraction
and scanning electronic microscopy – energy dispersive spectroscopy
were used to compare the results from the simulation with the mineralogical
and morphological composition of ash and deposits formed during combustion.
The thermodynamic modeling revealed to be a powerful tool in foreseeing
the formation of melt and liquids salts, depending on the temperature
and chemical composition of fuels. The main discrepancies observed
between the experimental and simulated data were due to particularities
of the combustion process, which are not incorporated in the software,
namely, kinetic limitations of the reactions, possible occurrence
of secondary reactions in the ashes, and elutriation effects of ash
and silica sand particles.