METHOD OF OBTAINING MELIORANT BASED ON NEUTRALIZED PHOSPHOGYPSUM Russian patent published in 2024 - IPC C05G5/12 C01F11/46 B01J2/28 

FIELD: chemistry.

SUBSTANCE: invention relates to the production of granular neutralized phosphogypsum used as an ameliorant, as well as a calcium-containing fertilizer. The original pulp of dihydrate phosphogypsum is filtered, filtered phosphogypsum with a moisture content of 25–30% is mixed with phosphogypsum dried to a moisture content of no more than 1% to obtain a moisture content of 13–15%. The resulting phosphogypsum is dried at a temperature of not more than 130°C until the moisture content is not more than 1%, pierced to a moisture content of not more than 0.01% and mixed with a binder solution with a volume concentration of not more than 50 g/l and a temperature of 20–40°C, followed by granulation by the rolling method until the granule size reaches 2 up to 5 mm with a content of at least 95%. Subsequent drying is carried out at a temperature of 50–60°C until the moisture content does not exceed 10%, after which it is classified.

EFFECT: method makes it possible to obtain granular ameliorant based on phosphogypsum with increased granule strength of 30–60 kgf/m².

1 cl, 3 ex