Patent ID: 7901583
Filing Date: 2011-03-08
Classification: B03D,C02F

Abstract:
1. A process of rigidifying a mineral material whilst retaining the fluidity of the material during transfer, in which the material comprises an aqueous liquid with dispersed particulate solids is transferred as an underflow from a thickener to a deposition area, then allowed to stand and rigidify and release aqueous liquid, by combining with the material an effective rigidifying amount of an aqueous solution of a water-soluble polymer having an intrinsic viscosity of at least 5 dl/g (measured in 1M NaCl at 25° C.), wherein the water-soluble polymer is anionic and is formed from ethylenically unsaturated water-soluble monomer or blend of monomers, and wherein the water-soluble polymer is formed from monomer(s) selected from the group consisting of (meth)acrylic acid, allyl sulphonic acid and 2-acrylamido-2-methyl propane sulphonic acid as the free acids or salts thereof, optionally in combination with non-ionic co-monomers, selected from the group consisting of (meth)acrylamide, hydroxy alkyl esters of (meth)acrylic acid and N-vinyl pyrrolidone.