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DeNOx SCR

DeNOx-SCR (Selective Catalytic Reduction) is a proven technology for the efficient reduction of nitrogen oxides (NOx) from industrial exhaust gas streams at low to medium temperatures. In this process, nitrogen monoxide (NO) and nitrogen dioxide (NO₂) are converted into environmentally harmless nitrogen (N₂) and water (H₂O), with NO₂ being of particular importance due to its higher toxicity.

Several chemical reaction mechanisms occur simultaneously during NOx reduction:

Standard SCR
4 NO + 4 NH₃ + O₂ → 4 N₂ + 6 H₂O

Fast SCR
NO + 2 NH₃ + NO₂ → 2 N₂ + 3 H₂O

NO₂-SCR
8 NH₃ + 6 NO₂ → 7 N₂ + 12 H₂O

C&CS SCR catalysts enable highly efficient NOx reduction even in oxygen-containing exhaust gases. Ammonia is used as the reducing agent, either directly or in the form of urea. Our experts support the design of SCR systems, including the calculation of the required reducing agent quantities, the optimal catalyst volumes, and the sizing of the SCR reactor. In addition, operation requires a precise injection unit and supporting system components.

Compared to selective non-catalytic reduction (SNCR), DeNOx-SCR technology using vanadium catalysts operates at significantly lower temperatures and therefore achieves higher NOx reduction rates while simultaneously reducing energy consumption.

The SCR catalysts used in these applications by C&CS are primarily based on vanadium oxide and are designed for a defined service life. Once the operating lifetime has been reached, the vanadium catalysts are replaced. C&CS provides the planning, engineering, and supply of complete SCR systems, including pre-assembled stainless steel support frames. Precise design of the SCR modules and their professional installation are essential for ensuring long-term stable and efficient operation.