Hybrid SNCR/SCR Systems for NOx reduction

Hybrids are the optimal choice where the need for NOx reduction is high but space limitations are present. Hybrid systems are the most flexible choice of reducing NOx emissions.

Power plant

In recent years, new NOx control hybrid systems, using a combination of SNCR and SCR technology, have been developed. These hybrid systems reduce the level of nitrogen oxides (NOx) in fossil fuel combustion flue gas with a selective non-catalytic reduction (SNCR) treatment stage followed by a selective catalytic reduction (SCR) treatment stage.

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.

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

Ed Wells
Ed Wells
VP, Environmental Solutions, North America