LOW-FLUORINE PHOSPHATIC FERTILIZER AND METHOD FOR MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a phosphatic fertilizer which is little in a fluorine content and fluorine elution rate. SOLUTION: This low-fluorine phosphatic fertilizer is decreased in the fluorine content to <=0.2 wt.% and the fluorine elution rate to <=25 mg/l, more preferably to <=8 mg/l by a first process step of preparing a sulfuric acid decomposing slurry by using raw material (phosphoric acid-lime raw material) essentially consisting of phosphoric acid-lime obtained from phosphoric acid subjected to defluorination treatment and adding sulfuric acid to this raw material and a second process step of adding the phosphoric acid-lime raw material and basic material to the slurry to neutralize the slurry and fixing the fluorine liberated into the slurry.