| abstract |
Water purification process, in which a natural calcium carbonate whose surface has undergone reaction is brought into contact with the water to be purified, so that the natural calcium carbonate whose surface has undergone reaction is the reaction product of a natural calcium carbonate with an acid and carbon dioxide, which is formed in situ by treatment with acid and / or supplied externally, and the natural calcium carbonate whose surface has undergone reaction is prepared in the form of an aqueous suspension having a pH greater than 6.0, measured at 20 ° C, and a polymeric flocculant is added to the water to be purified after the addition of the natural calcium carbonate whose surface has been reacted. |