A twin-fluid nozzle in the SCR dosing system uses compressed air to inject and atomize the required mass of reducing agent (aqueous urea solution 32.5%, 40% or 45%, comparable with AdBlue® for motor vehicles) into the exhaust gas flow at the beginning of the mixing section. The exhaust gas heat in the mixing section (> 280 °C) causes the urea solution to evaporate, with the subsequent thermolysis and hydrolysis reactions then releasing ammonia (NH3). Alternatively, it is also possible to use SCR dosing systems that feed ammonia gas directly into the mixing section from a pressure cylinder or gas tank.
We can also design our SCR reactor so that it simultaneously acts as a silencer, removing the need for an additional exhaust silencer in some applications.
If an additional silencer is used, please note that absorptive silencers in particular should only be placed downstream of the SCR catalyst; otherwise, any insulation wool that comes loose from the silencer may cause irreparable damage to the catalyst.
Current and future emission limit values require an individual compilation of the exhaust gas treatment system to integrate the systems in the best possible way into new or existing applications. We have various concepts for the combination of particle filters and SCR DeNOx systems. An engineering team of highly qualified employees with years of experience takes over the conception and further development of SCR DeNOx systems, thermal management systems, soot particle filters, oxidation catalysts, programming and controls. With the SCR DeNOx systems (Selective Catalytic Reduction) from Fischer Abgastechnik you always comply with the latest limit values of the exhaust gas regulations.