Selective Catalytic Reduction (SCR)

The Selective Catalytic Reduction (SCR) process reduces NOx emissions to harmless substances normally found in the air that we breathe.
Reducing NOx emissions by 85-95%, SCR is currently the most efficient method of NOx reduction. Hence, it is easy to reach a NOx level of 2 g/kWh or lower, which complies with the most stringent levels at sea.

NITROGEN OXIDE REDUCER (NOR)
Wärtsilä has developed an SCR programme to cover its medium-speed engine portfolio. The size of  the SCR is optimized in terms of performance and cost in order to deliver the best solution. This approach also supports the highest availability of spare parts at all times. Tailor-made solutions are, however, also available.
The SCR product for Wärtsilä medium-speed engines is named Nitrogen Oxide Reducer (NOR). An SCR installation consists basically of a reactor, which is the core of the installation, an injection unit and a compact unit, where the urea solution is pumped and dosed for the desired NOX reduction. This compact unit is provided with dedicated control cabinet. As alternative, the urea solution can be fed with separated pumping unit and dosing unit, which are controlled by a separated control unit.