Abstract: Tripe superphosphate（TSP） was manufactured by den process，with phosphorite and raffinate phosphoric acid by- produced from wet process phosphoric acid purification process as the raw material.The effects of phosphoric acid concentra- tion，reaction temperature，phosphorite fineness，solid content of phosphoric acid，and the ratio of acid to phosphorite mineral on decomposition rate and product quality of TSP were investigated by single factor experiment.The optimal conditions were obtained as follows: phosphoric acid concentration was at least 43%，solid content（mass fraction）was less than 8%，the ratio of acid to mineral［m（P2O5）acid/m（P2O5）mineral］was 2.6，reaction temperature was at 45～65 ℃，reaction time was 2～ 3 min，den process time was 20～25 min and the den temperature was 80℃，ripening temperature was 55 ℃，and ripening time was 8～14 d.Under these conditions，TSP could meet the standard of first class products.Meanwhile，phosphoric acid sludge and raffinate were utilized comprehensively，so that the storage problem of raffinate phosphoric acid would be solved，which would bring significant economic and social benefits.

Key words: wet process phosphoric acid, raffinate phosphoric acid, tripe superphosphate, den process