Using SCR to reduce pollution from biomass combustion
SCR stands for Selective Catalytic Reduction, and is a technology used for breaking down oxides of nitrogen (NOx).
In chemistry, ‘reduction’ refers to a reaction in which oxygen atoms are separated from another element, i.e. it is the opposite of oxidation.
In hot processes, oxides of nitrogen are often formed and these are harmful pollutants which are of increasing concern.
Selective catalytic reduction works by introducing another compound, termed a ‘reductant’, which encourages the oxygen atoms to ‘jump ship’ from the NOx molecules to react with the reductant instead.
In most cases, a catalytic converter is used to promote this reaction, in which case it occurs in the temperature range of 150-600oC.