Boiler operation with decreased NOx and waste water discharge

摘要

Pollution from industrial plants which produce NOx and waste water is reduced by utilizing waste water to prepare aqueous NOx-reducing solutions. Total water hardness in the waste water is preferably maintained below 2500 ppm, silicate below 200 ppm and the calcium to magnesium ratio above 2:1. The aqueous NOx-reducing solution will preferably contain hardness suppressing compostions in effective amounts.