Hybrid SNCR/SCR Systems

Hybrid systems SNCR/SCR for NOx reduction

NOx reduction

Recent years have seen the development of hybrid systems for NOx reduction, using a combination of SCR and SNCR technologies. These hybrid systems reduce the level of nitrogen oxides (NOx) in the flue gas with a hydrocarbon treatment in 2 stages: selective non-catalytic reduction (SNCR), followed by selective catalytic reduction (SCR).

Why choose a hybrid SNCR/SCR system?

A hybrid system may be an interesting alternative versus installing a single SCR system. Hybrid systems help to find a balance between investment costs (CAPEX) and operating costs (OPEX). This is particularly useful for cases where:

  • A significant reduction in NOx emissions is expected, yet flexibility of operation is needed 
  • The installation space available for the catalyst is restricted 
  • Increasing the pressure drop is critical or leads to higher operational costs and significant investments

In such cases, the hybrid solution is the best choice : it reduces the size of the catalyst to be installed, thus reducing investment, and volume issues at the site.

Learn more about SNCR systems from Yara.

If you have questions about SCR/SNCR hybrid systems, please contact our experts on NOx control.