The invention discloses an
ammonium phosphate drum
granulation method which comprises the following steps: step 1) pre-reaction of a tube reaction tank and a pre-
neutralization tank: acid
sludge of a
phosphoric acid device, a washing solution of a pre-washing
tower and process water firstly enter a pre-
washer and then enter the tube reaction tank,
sulfuric acid is added, stirring reaction is performed in the tube reaction tank, and the
reaction product is output through a tube C; acid
sludge of a
phosphoric acid device, washing liquid of a pre-washing
tower and
tail washing water enter a pre-
neutralization tank, and the temperature of reaction
slurry of the pre-
neutralization tank is controlled through a steam
pipe on the outer wall of the pre-neutralization tank and output through a
pipe A and a
pipe B; 2) mixing tube reaction: mixing the liquid in the tube A and the tube C to react again; and (3) granulating, namely feeding the liquid after reaction in the mixing tube into a granulator, and adding
liquid ammonia for granulating to obtain the product. And the tube A, the tube B and the tube C react to realize a 2 + 1 tube reaction process (the tube A reaction, the tube B reaction and the tube C reaction). In the DAP production period, the high-
solid-content
slag acid and the extraction-residue concentrated acid are used in the tube reaction, and the
slag acid and the extraction-residue concentrated acid directly enter the tubular reactor by bypassing a washing
system, so that the DAP production cost is reduced, the stock pressure of the
slag acid is relieved, and frequent blockage of the washing
system caused by the high-
solid-content slag acid and the extraction-residue concentrated acid is also avoided.