Method for grinding calcium carbonate in water in the presence of a solution of acrylic polymer and an alkali carbonate salt manufactured in place in the said solution

摘要

A method for manufacturing an aqueous suspension of calcium carbonate by grinding in an aqueous medium in the presence of an acrylic grinding aid agent and of an alkali carbonate salt. These salts enable the quantity of grinding aid agent used to be reduced, for an equivalent level of performance in terms of rheology and granulometry of the suspensions. The method includes a first step of manufacture of the alkali carbonate salt within the aqueous solution of acrylic polymer itself, through the addition of alkali hydroxide and bubbling of carbon dioxide.

主权项

1. A method of manufacturing an aqueous suspension of calcium carbonate, comprising:
a) preparing an aqueous solution comprising water, at least one water-soluble polymer of acrylic acid, and an alkali hydroxide, where the quantity of hydroxide present is greater than that required for total neutralisation of the polymer, b) introducing into the aqueous solution, during and/or after its preparation in a), gaseous carbon dioxide to provide a grinding aid solution, c) introducing the grinding aid solution into an aqueous suspension comprising water and calcium carbonate to produce a grinding suspension, and d) grinding the grinding suspension,
wherein an alkali carbonate salt is formed in b).