Die zirkulierende Wirbelschicht als Reaktionssystem für katalysierte Gas/Feststoff‐Reaktionen

Abstract

AbstractThe circulating fluidized bed reactor for catalyzed gas/solid reactions. For many years circulating fluidized beds (CFB) have been successfully employed for a variety of technical applications, e.g. for dry sorption processes to clean waste gases from alumina electrolysis, waste incinerators, and from coal dust combustion. A new application of the CFB principle, the dry and simultaneous removal of nitrogen oxides and sulfur oxides both from power plant and industrial waste gases has been developed and tested in laboratory‐scale, bench‐scale, and pilot plant facilities and has since reached technical maturity. In this dry DeNOx/DeSOx process, desulfurisation is accomplished by dry sorption with Ca(OH)2 whereas NOx is eliminated by selective catalytic reduction (SCR) with NH3 as reducing agent. To perform the process in a CFB reactor, powder‐like DeNOx catalysts are required. Referring to the simultaneous DeNOx/DeSOx CFB‐process, the main features of highly expanded gas/solid reaction systems as well as the requirements for fine catalyst particles used therein are evaluated. First basic results of the simultaneous NOx und SOx removal from firing gases in the CFB will be reported.