Patent ID: 8562838

Claim:
A method for treating sludge from the mining or mineral industry, comprising: before above-ground spreading of a sludge, contacting the sludge with a flocculating agent that is a water-soluble organic polymer having a molecular weight of from 5,000,000 to 25,000,000 g/mol and an anionicity of from 10 to 40 mol %, to produce a contacted sludge, wherein the water-soluble organic polymer comprises at least one anionic monomer having a carboxylic function or having a sulfonic acid function, at least one non-ionic monomer, and optionally one or more cationic monomers, wherein the flocculating agent is branched, and has from 0.02 to 2 mol % hydrophobic monomers, and the hydrophobic monomers comprise one or more members selected from the group consisting of a (meth)acrylic acid ester with an alkyl and ethoxylated chain; an anionic or cationic hydrophobic (meth)acryloyl derivative; and an anionic and/or cationic derivative of (meth)acrylamide bearing a hydrophobic chain.