Apparatus for prilling an oxidizing salt of ammonia

摘要

Prills of ammonium dinitramide (ADN) are prepared by melting this salt with a stabilizer and, by dry nitrogen pressure, injecting the molten salt into an inert, perfluorinated carrier liquid of greater specific gravity which, initially, is above the solidification temperature of the salt. The molten salt and carrier liquid pass together in turbulent flow through a heated conduit in which stationary vanes disperse the salt into droplets. The liquid and salt then pass in turbulent flow through a cooled conduit for solidification of the salt into prills without agglomeration. The prills are then separated from the liquid by flotation and any liquid carried with the prills recycled. The main flow of carrier liquid is pumped through a preheater and then back to the molten salt injector. The cooled conduit is provided with compression refrigeration, the refrigerant passing in parallel flow along the conduit and the compressed refrigerant passing to the preheater before condensation.