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Staff of the Scientific Research Institute of Fertilizers, Insecticides, and Fungicides (NIUIF) and the Voskresensk Mineral Fertilizers chemical plant (VMU) have developed and adopted a method for obtaining diammonium phosphate, including: 9 mixing phosphoric and sulfuric acids to obtain a finished product suitable for export (N:P20 5 = 18:46), with an SO 3 content in the slurry equal to 6-7%; 9 neutralization of the mixture of acids in stages with ammonia to a mole ratio of NH3/H3PO 4 equal to 1.75; 9 granulation of the slurry in an ammoniator/granulator; 9 drying the product in a drying drum; 9 a system for removing harmful impurities from the gases (two-stage to remove ammonia and product dust, and one-stage to remove fluorinated compounds).Ammonia and product dust are collected by acid solutions of ammonium phosphates; fluorinated compounds are collected with a 0.3% aqueous solution of H2SiF 6 [1].The process of neutralization of acids is carried out in three tubular reactors: two are mounted in front of the ammoniator/granulator, one is mounted in front of the drying drum.Liquid ammonia, the mixture of acids, and absorption discharges are fed to the tubular reactors.Granulation and complete ammoniation of the ammonium phosphate slurry with liquid ammonia to a mole ratio NH3/H3PO 4 = 1.75-1.85 are carried out in the ammoniator/granulator. We established that when SO 3 ions are present in the slurry, the granulation process occurs more efficiently and uniformly, a larger number of granules of size 2-4 mm are formed, and the amount of the fine fractions is reduced.However, the ratio of P205 and SO 3 ions in the mixture of acids should be strictly controlled, since when the fraction of SO 3 ions decreases, the flowability of the slurry obtained is reduced; and when the fraction increases, the temperature rises, which causes an increase in the evolution of ammonia to the gas phase.The charge from the ammoniator/granulator with mole ratio -1.85 and moisture content 1.7-2.0% is directed to the drying drum, to which the ammonium phosphate slurry with mole ratio NH3/H3PO 4 = 1.0-1.05 is fed from the tubular reactor mounted in front of the drying drum, and using a sprayer is sprayed onto the product screen.In the drying drum, spontaneous evaporation of moisture from the slurry occurs, and the monoammonium phosphate formed is mixed with the charge.The gases exhausted after the ammoniator/granulator and the drying drum, containing product dust, ammonia, and fluorinated compounds, are fed to independent cleaning systems.The basic production parameters and the content of harmful components released into the gas phase during neutralization/granulation and drying of the product are presented in Table 1.