The importance of SO2 and SO3 for sulphation of gaseous KCl - An experimental investigation in a biomass fired CFB boiler
Journal article, 2010
This paper is based on results obtained during co-combustion of wood pellets and straw in a 12 MW circulating fluidised bed (CFB) boiler. Elemental sulphur (S) and ammonium sulphate ((NH4)(2)SO4) were used as additives to convert the alkali chlorides (mainly KCl) to less corrosive alkali sulphates. Their performance was then evaluated using several measurement tools including, IACM (on-line measurements of gaseous alkali chlorides), a low-pressure impactor (particle size distribution and chemical composition of extracted fly ash particles), and deposit probes (chemical composition in deposits collected). The importance of the presence of either SO2 or SO3 for gas phase sulphation of KCl is also discussed. Ammonium sulphate performed significantly better than elemental sulphur. A more efficient sulphation of gaseous KCl was achieved with (NH4)(2)SO4 even when the S/Cl molar ratio was less than half compared to sulphur. Thus the presence of gaseous SO3 is of greater importance than that of SO2 for the sulphation of gaseous KCl. (C) 2010 The Combustion Institute. Published by Elsevier Inc. All rights reserved.
In situ Alkali Chloride Monitor (IACM)
aerosol formation
part 1
KCl
Alkali chlorides
chlorine deposition
alkali
of biomass
rich biomass
combustion
fluidized-bed boiler
ash
wood
Fluidised bed combustion
Sulphation
particles
gas-phase
Combustion
Author
Håkan Kassman
Chalmers, Energy and Environment, Energy Technology
L. Bafver
SP Sveriges Tekniska Forskningsinstitut AB
Lars-Erik Åmand
Chalmers, Energy and Environment, Energy Technology
Combustion and Flame
0010-2180 (ISSN) 15562921 (eISSN)
Vol. 157 9 1649-1657Subject Categories
Chemical Engineering
DOI
10.1016/j.combustflame.2010.05.012