Stricter NOx emission requirements mean that SNCR either require excessive ammonia dosing or is not sufficient, and therefore SCR (selective catalytic reduction) becomes necessary. Dedicated SCR reactors for NOx reduction is a well-known technology but require substantial investments to be implement-ed in an existing flue gas treatment facility.
Haldor Topsøe has in collaboration with FLSmidth developed a filter bag which functionally is a combined filter bag and SCR catalyst. This CataFlex™ filter bag works as a drop-in solution for systems with fabric filters for dust removal. Installation of CataFlex catalytic filter bags enables the reduction of NOx levels directly across the filter bag, whereby a separate investment-heavy SCR reactor and associated piping system can be avoided. The catalyst is the same as used in conventional SCR, and NH3 injection is required.
Especially on plants where removal rates that can be obtained using SNCR becomes insufficient due to tightening of NOx requirements, CataFlex™ will be able to ensure that the plant can be in compliance with new and stricter requirements for NOx emissions without entailing significant rebuilds like the traditional SCR solution requires.Læs publikation