Abstract: An improved process in the preparation of sustained release fertilizer compositions which comprises subjecting a preponderantly water-soluble granular fertilizer composition first to accretive granulation under accretive granulation conditions with a melt, solution or slurry of one or several fertilizers and in a second stage coating these treated grains with a suitable almost impermeable envelopment.

Abstract: Ammonium polyphosphate is manufactured on a continuous basis by reacting gaseous ammonia and aqueous phosphoric acid at elevated temperatures in a one or multiple stage falling film reaction zone in the presence of a diluting gas if desired, using wet phosphoric acid, preferably containing 28-32%, by weight P.sub.2 O.sub.5 and an excess of ammonia. The phosphoric acid and the gaseous ammonia are preferably carried in counterflow and the temperature in the falling film reaction zone is adjusted using heat transfer fluids to within the range of 120.degree. - 260.degree. C.

Abstract: Stabilized ammonium nitrate is prepared from ammonium nitrate melts by removing substantially all of the water from said ammonium nitrate melt, then adding polyphosphates in an amount of 0.1 to 1.0% by weight and finally converting the melt to a solid state.