Procedure to reduce nitrous oxide (N2O) emissions in a combustion installation and an installation for embodiment

Abstract

A procedure wherein a catalyst pertaining to the family of zeolites is injected into the vessel ( 1 ) of the circulating fluidized bed, in powder form. The installation includes a vessel ( 1 ) in which the top is connected to a separator ( 3 ) in which the bottom is connected to the vessel ( 1 ) by a recirculation loop ( 4 ), a silo ( 5 ), in which the catalyst based on crushed zeolites is stored, and which is connected by a conveyer ( 6 ) to the recirculation loop ( 4 ).

1 . A procedure to reduce nitrous oxide N 2 O emissions in a combustion installation which includes a vessel ( 1 ) operating as a circulating fluidized bed, wherein a catalyst pertaining to the family of zeolites is injected into the vessel ( 1 ) of the circulating fluidized bed in powder form.  
     
     
         2 . The procedure in accordance with    claim 1   , in which the catalyst injected into the vessel represents between 0.2 and 5% of the charge of solids circulating in the vessel.  
     
     
         3 . The procedure in accordance with    claim 1   , in which the catalyst has an average diameter ranging between 0.05 and 2 mm.  
     
     
         4 . The procedure in accordance with    claim 1   , wherein said catalyst is injected into the vessel ( 1 ) through a recirculation loop ( 4 ) connecting the bottom of a separator ( 3 ) to the bottom of the vessel ( 1 ).  
     
     
         5 . An installation for the embodiment of the procedure in accordance with    claim 1   , including the vessel ( 1 ) which operates as a circulating fluidized bed, a top of the vessel being connected to a particle separator ( 3 ) in which the bottom, which recovers the largest solid particles ( 2 ) present in combustion smoke, is connected to a bottom of the vessel ( 1 ) through a recirculation loop ( 4 ) equipped with a siphon, wherein a silo ( 5 ), in which a catalyst based on crushed zeolites is stored, is connected through a transport system ( 6 ) to the recirculation loop ( 4 ).