Title:
Formation of Fine Particulate Matter in a Domestic Pellet-Fired Boiler
Author(s):
Fernandes, U., Madeira, J., Costa, M.
Document(s):
Paper
Abstract:
This study concentrates on the formation of fine particulate matter (PM) in a domestic pellet¬ fired boiler, and includes a detailed characterization of the combustion process inside the combustion chamber of the boiler. Measurements of local gas temperatures, major gas species concentrations and PM concentrations and size distributions are reported for a representative boiler operating condition. In addition, a number of selected PM samples were also morphologically and chemically characterized. The results revealed that (i) particles smaller than 0.1 .m are rapidly formed at the beginning of the combustion process, where the oxidation rate is also high; however, the oxidation rate decreases rapidly along the combustion chamber height due to the significant temperature drop; (ii) the diameter corresponding to the maximum amount of particles increases slightly from the burner until ~4/5 of the combustion chamber height, indicating some tendency for aggregates formation; in the final region of the combustion chamber is observed a decrease in the diameter corresponding to the maximum amount of particles, as consequence of some PM fragmentation; (iii) the carbon present in the particles significantly decreases along the combustion chamber and the inorganic elements tend to condense and solidify with the temperature decay along the chamber; and (iv) in the post flame region the small particles are wrapped by inorganic compounds that deposited on them by heterogeneous condensation.
Keywords:
boiler, pellet, particle emissions
Topic:
R&D on Biomass Conversion Technologies for Heating, Electricity and Chemicals
Subtopic:
Solid biofuel combustion for small and medium scale applications
Event:
20th European Biomass Conference and Exhibition
Session:
2BO.4.1
Pages:
717 - 722
ISBN:
978-88-89407-54-7
Paper DOI:
10.5071/20thEUBCE2012-2BO.4.1
Price:
FREE
