SCR Technology can achieve more than 95% NOx reduction. SCR is the absolute NOx control system.
SCR technology for reducing NOx emissions
Selective Catalytic Reduction (SCR) is a method to reduce the level of nitrogen oxides (NOx) with the help of a catalyst.
SCR technology can achieve more than 95% NOx reduction in combustion processes and can meet stricter incoming legislation.
It is the absolute NOx control system.
With SCR technology:
- The temperature of the flue gas is much lower than in SNCR systems
- A catalyst is needed to reduce nitrogen oxides with the help of a reducing agent ( anhydrous ammonia, ammonia solution, urea solution). The NOx and ammonia enter the catalyst, causing the NOx to react with the ammonia to produce elemental nitrogen and water. It ensures that you reach good NOx control level, up to 95% reduction
- The reagent consumption is optimized
- Investment costs are high (Capex) given the catalyst but also its whole installation
- The maintenance costs are high as you regularly need to renew the catalyst – when it shows signs of decreasing performance
When choosing SCR technology it is also important that you choose a reliable reagent supplier for ammonia or urea to ensure you are always meeting your legal requirements in terms of NOx emission reduction.
A reliable supplier guarantees continuous deliveries of the reagent. Without the reagent, your NOx control unit will stop as you will be over the emissions limits prescribed for your site according to the Clean Air Act.
Furthermore the quality of the reagent is particularly important to meet the strict demands of your catalyst supplier to ensure a long and maintenance free life-time of your catalyst.
Yara has been producing and delivering its reagents to clients for over two decades from our unique network of production plants which offer a constant back-up in sourcing, thus guaranteeing both supply and quality.
When choosing how to reduce NOx emissions, the feasibility and the economy of SNCR technology should also be investigated. The investment cost of an SNCR system is only a fraction of a complete SCR installation.