METHOD OF PRODUCING DICALCIUM PHOSPHATE FEED Russian patent published in 2009 - IPC C01B25/32 

FIELD: chemistry.

SUBSTANCE: method of producing dicalcium phosphate feed involves a first stage, specifically treatment of calcined phosphogypsum with an alkaline carbonate-containing reagent to pH ranging from 9.15 to 10, a second stage, specifically mixing chalk pulp obtained at the first stage with purified phosphoric acid to pH ranging from 5.4 to 6 with subsequent filtration and drying the finished product. According to the invention, the first stage is carried out with initial ratio of liquid phase to solid phase equal to 4.7-5.5:1, after which the chalk pulp is thickened until attaining ratio of liquid phase to solid phase equal to 3-4:1, and the second stage is carried out until attaining ratio of liquid phase to solid phase equal to 4-4.7:1.

EFFECT: method allows for increasing output of P₂O₅ into the final product and so reducing loss of P₂O₅.

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