METHOD OF PRODUCING CHEMICALLY PRECIPITATED CHALK Russian patent published in 2019 - IPC C01F11/18 

FIELD: technological processes.

SUBSTANCE: invention relates to production of inorganic materials, namely chemically deposited chalk, intended for food, medical, perfume-cosmetic, chemical, petrochemical, paint and other industries. Method of producing chemically precipitated chalk includes annealing of natural chalk to lime with extraction of carbon dioxide, suppression of obtained lime with water to lime milk, filtration on vibrating sieves, carbonization of purified lime milk with production of chalk milk with carbon dioxide. Further, the obtained chemically precipitated chalk is dried. Prior to drying, lime milk is washed in the medium of complete ozonation of air. Calcination, quenching and carbonization are carried out in the medium "air: ozonized air". Duration of annealing of natural chalk makes 1–10 hours from the moment of reaching of 850–900 °C in natural chalk loading zone.

EFFECT: invention simplifies the technology of producing chemically precipitated PCC chalk while improving the quality of the finished product.

7 cl, 1 dwg