Experiments were conducted in a fluidized bed with I.D.of 81?mm and height of 1600?mm to investigate NO x emissions from incineration of waste water,which contains hexamethylenediamine of 4.5% and dilute HNO 3 of 1.25%.The result shows that decomposition products of dilute HNO 3 water solution are NO and NO 2.NO is the main product,which represents more than 90% of total NO x.The conversion ratio of HNO 3 converted to NO x is about 95%~96%.The results of incinerating organic waste water in a temperature range from 800?℃ to 950?℃ shows that,under non-staged combustion condition,the de-NO x ratio is only about 46%~61% at oxygen concentration of 11%.Staged combustion was adopted to further decrease NO x emission.The experimental data indicate that the NO x emission can be reduced very efficiently,the de-NO x ratio is increased up to 86%-93%.It was found that the presence of hexamethylenediamine is positive for reduction of NO x emission.950?℃ is the optimal operation temperature for incineration of the examined waste water,concerning the NO x reduction.