Along with greater NOx reduction, this system eliminates the need and expense of ammonia handling and results in a much smaller catalyst section than would be required in a stand-alone conventional SCR system. Also it builds on the ability of the upstream system by further reducing NOx emissions, and by providing the excess ammonia necessary to charge the SCR catalyst.

Benefits:

• 20%-40% additional NOx reductions beyond SNCR for standard utility boilers.
• Expands optimum temperature range for a boiler system as a whole.
• Significant cost savings over conventional SCR system (amount of catalyst is reduced, lowering initial capital investment and subsequent replacement catalyst costs).
• Eliminates expensive and hazardous handling of ammonia.

How it works:
The CASCADE technology relies on an SCR catalyst reactor placed into the flue gas ducting. Ammonia produced by over injection of SNCR chemicals reacts with the cascade catalyst to further reduce NOx. Combining the SNCR and SCR technologies in this fashion dramatically expands the temperature range for reducing NOx production.