FOERFARANDE FOER FRAMSTAELLNING AV GRANULER INNEHAOLLANDE KARBAMID SOM HUVUDKOMPONENT

摘要

A process for making granules containing urea as the main component by spraying an aqueous urea solution having a urea concentration of 85-98% by weight, to which solution magnesium hydroxide, an inorganic magnesium salt or a mixture of such substances has been added as a crystallization retarder for the urea, and which solution optionally contains one or more other fertilizers in solution and/or suspension, is sprayed in the form of very fine droplets having an average diameter of between 20 and 120 micron into a fluidized bed of urea particles at a temperature at which the water on the solutions sprayed onto the particles is evaporated, and urea or urea containing material solidifies on the particles, to form granules having a desired size. The urea granules thus produced are compatible with single and triple superphosphate granules.