Entrained Flow Reactor Study of KCl Capture by Solid Additives

An option for abating deposition and corrosion caused byalkali species during biomass combustion, is the introduction of additivesinto boilers for transforming harmful gaseous alkali compounds (e.g. KCl,KOH) into less corrosive ash species with a higher melting point. Kaolin andcoal fly ash have been proved to be very promising additives and havereceived extensive studies during the past decades. However, mostprevious studies were carried out in fixed-bed reactors where the reaction conditions are obviously different from that in suspension fired boilers.Detailed knowledge on the reaction between K-species and solid additivesunder suspension-fired conditions is still limited. In this study, a water slurrycontaining K-salt and solid additives was introduced into an entrained flowreactor (EFR) to study K-capture at suspension-fired conditions. A model willbe developed based on experimental data and recommendations for optimaluse of additives in full scale boilers will be provided.