SCRT

Functionality

The proven HJS ^SMF® technology with passive regeneration is used to break down the soot accumulated in the ^SMF®. The upstream oxidation catalytic converter converts the nitrogen monoxide (NO) present in the exhaust gas into nitrogen dioxide (_NO2). The particulate filter then uses the nitrogen dioxide (_NO2) produced for continuous combustion of the soot residue (soot oxidation).

However, the downstream SCR system (SCR = Selective Catalytic Reduction) is used to reduce nitrogen oxides (_NOx). To convert the nitrogen oxides, an additional fuel based on urea (brand name ^AdBlue®) is added to the exhaust gas, usually downstream of the diesel particulate filter. In the hot exhaust gas, the AdBlue® is converted ^thermallyand catalytically to ammonia (_NH3). This ammonia now acts as a reducing agent for the nitrogen oxides (_NOx) and converts them into harmless nitrogen (_N2) and water (_H2O) at the SCR catalytic converter. The SCR unit thus reduces the environmentally harmful and unhealthy nitrogen oxide emissions of diesel engines by up to 99 percent. Together with the HJS particulate filter, the SCR system thus reduces almost all pollutants in diesel exhaust gases (^SCRT® system = DPF + SCR system).

Area of application

The ^SCRT® system is used in both passenger cars and commercial vehicles and is the leading system architecture for vehicles of the Euro VI/6 or EPA 2010 generation when it comes to really clean exhaust gases. In addition, it will also be standard for many “non-road” diesel engines, i.e. for use in construction machinery as well as agricultural and forestry machinery, from 2019 at the latest. This technology is also used for stationary engines or rail and marine applications. HJS ^SCRT® systems are available both for original equipment applications and for retrofitting.