THERMAL SCIENCE

International Scientific Journal

EFFECTS OF BIOMASS ON DYNAMICS OF COMBUSTION IN CIRCULATING FLUIDIZED BEDS

ABSTRACT
Fluidized bed technology is very suitable for the combustion of biomass Nevertheless substitution of coal with biomass affects boiler operation and especially dynamics and controllability. Non-homogeneity of biomass and fuel feeding disturbances cause process instability, such as variations in temperatures and pressures, which reduce lifetime of equipment and structures. Because of process instability higher air coefficient must be used in order to avoid CO emissions, which is not economical. Combustion profiles for coal, wood and peat, measured at the VTT Processes Pilot circulating fluidized bed reactor, have been compared. Process stability and char inventories have been studied by the measurements and the model. Biofuel are usually very reactive and their combustion profiles are quite different compared to coals. Because of high reactivity and low char content combustion process with biofuel is very sensitive for fuel feeding. Also low char inventory effect on load changes combined with combustion profile that differs from coals. Because of different combustion profile heat transfer can be a limiting factor in load changes despite the high reactivity and fast oxygen response.
KEYWORDS
PAPER SUBMITTED: 2004-03-06
PAPER REVISED: 2004-04-20
PAPER ACCEPTED: 2004-08-27
DOI REFERENCE: https://doi.org/10.2298/TSCI0402093T
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2004, VOLUME 8, ISSUE Issue 2, PAGES [93 - 105]
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© 2022 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence