Dear All,
i have a small querry that from preheater stack yellow fumes are coming i have checked all possible things like alkali,chalorides so any one can give me a specific reason for these yellow fumes.
Ted Krapkat
Yellow (or orange) fumes indicate an excessive amount of NOx coming out of your stack. This indicates a very hot main burner and/or calciner burner flame temperature combined with highly oxidising kiln conditions.
As a last resort, NOx can be reduced by adding a small amount of ammonia or urea solution to the preheater gas stream at a location upstream from the pre-calciner, where the gas temperature is between 850 and 1150 deg.C.
Plenty of information on this process is available on the internet.
Regards,
Ted.