Title:
Long Term Corrosion Measurements during Injection of Ammonium Sulphate in a Biomass Fired BFB Boiler
Author(s):
Kassman, H., Astervik, Å., Mattsson, M., Stålenheim, A., Henderson, P.
Document(s):
Paper
Poster
Abstract:
Combustion of biomass with increased chlorine (Cl) contents can result in operational problems including increased deposit formation and superheater corrosion, because of the higher levels of alkali chlorides (KCl and NaCl) in the flue gas. Various strategies can be applied to reduce such problems and one of these is the use of on-line monitoring of alkali chlorides (IACM In-situ alkali chloride monitor) and sulphate-containing additives such as ammonium sulphate (AS). This is known as the ChlorOut concept and has been used in the work presented here. The sulphate additive which is sprayed into the flue gases in an appropriate position prior to the superheaters converts alkali chlorides into less corrosive alkali sulphates. This paper is based on measurements during combustion of demolition (used) wood in a 63 MWth Bubbling Fluidised Bed (BFB) boiler in Jordbro, Sweden. Results from long-term corrosion probe measurements carried out during the injection of ammonium sulphate (AS) and without injection (Reference) were compared. There was a significant difference in material loss from high temperature corrosion between the two cases at higher temperatures and a steep increase in corrosion rate is observed for the reference case above 460°C. The results revealed that injection of AS according to the ChlorOut concept can be applied as a strategy to reduce the corrosion rate of the superheaters in the boiler in Jordbro.
Keywords:
biomass, IACM, KCl, ammonium sulphate, high temperature corrosion, superheaters
Topic:
Biomass Conversion Technologies for Heating, Cooling and Electricity
Subtopic:
Biomass combustion in large utilities
Event:
24th European Biomass Conference and Exhibition
Session:
2BV.1.59
Pages:
777 - 781
ISBN:
978-88-89407-165
Paper DOI:
10.5071/24thEUBCE2016-2BV.1.59
Price:
FREE
