Whereas the previous measures are designed to
reduce the formation of nitric oxide, reburrdng
reduces existing nitric oxides. Especially if nitrogen
containing fuel is used, the formation of 'fuel NO',
often cannot be avoided. In that case, a reburning fuel
could be injected to the combustion products to
reduce the NO to N2. The reburning fuel could be
either the same fuel as the main fuel, or another fuel,
To achieve good results, the reburning process has to
take place in a specific temperature range and a good
homogeneous mixture has to be provided, s Secondary
air must be injected further downstream to achieve
complete oxidation of the reburning fuel. Because the
reburning process could take place in the combustion
chamber or further downstream, depending on the
process conditions, reburning could be named either a
primary or as a secondary measure. Typical steps for
a reburning process are shown in Fig, 7. Reburning is