GEA to supply thomas zement turnkey plant for the reduction of NOx in flue gas

GEA competence in selective catalytic reduction

Selective catalytic reduction (SCR) is a technique for the reduction of nitrogen oxides in exhaust gases from industrial plants. The chemical reaction at the SCR catalyst is selective. This means that the nitrogen oxides (NO and NO2) are preferably reduced, while undesirable side reactions such as the oxidation of sulphur dioxide to sulphur trioxide are largely suppressed. SCR technology reduces nitrogen oxide (NOx) in the the catalyst passing gas flow upto 95 percent. The core is the catalyst, which makes it possible to reduce the reaction temperature from around 1000°C to a range of 230°C to 400°C. High reduction rates can thus be achieved with a minimum of ammonia slip.

Due to an adequate low sulphur concentration and a sufficient temperature level, the SCR unit is installed low-dust behind the existing fabric filters. This arrangement has already proven itself in three successfully operated plants with the lowest NOx and NH3 emissions. Analyses of catalyst samples consistently show no loss of the high reactivity of the selected material and thus a long catalyst life.