Method of making granular triple superphosphate fertilizer

摘要

Disclosed is a method of making granular superphosphate by reacting comminuted phosphate rock with phosphoric acid. The process involves two reaction steps. A predetermined amount of phosphoric acid is reacted with phosphate rock in quantities to produce a flowable fluid excess acid slurry which will remain liquid and fluid at the temperature of the reaction. The slurry is then injected into an agitating mixer containing comminuted phosphate rock. The ratio of slurry to phosphate rock in the mixer is controlled to complete the reaction between the phosphate rock and phosphoric acid and produce a granulated superphosphate product having a moisture content of about 5% or less.