| abstract |
The present invention relates to a process for the purification of water or for dehydration of sludge, comprising the steps of bringing into contact a natural treated calcium carbonate on the surface, a natural bentonite and an anionic polymer with the water or mud, forming flocs by gathering particulate substances contained in the water or in the mud, and separating the flocs formed in order to obtain purified water or water separation in order to obtain a dehydrated mud; in the case of natural calcium carbonate treated on the surface, it is a reaction product of a natural calcium carbonate with an acid and carbon dioxide, which is formed in situ by treatment with an acid and / or which is supplied from the outside, and is prepared in the form of an aqueous suspension with a pH value, measured at 20 ° C, greater than 6.0; The present invention also relates to a composition comprising a natural surface treated calcium carbonate, a natural bentonite and an anionic polymer for water purification or for sludge dehydration. |