NZ514405A - Higher actives dispersion polymer to aid clarification, dewatering, and retention and drainage in water treatment - Google Patents

Abstract

A method for the treatment of waste water with an effective clarifying amount of at least one dispersion of a water soluble cationic polymer flocculant; where the water soluble flocculant is added to the water in an effective amount to flocculate suspended solids, the suspended solids are removed, and a clarified water is obtained, the dispersion of the water soluble cationic polymer flocculant formed from polymerizing vinylic monomers under free-radical forming conditions in a medium containing water, monomers, stabilizer polymer, and an aqueous anionic salt solution; where the water-soluble cationic polymer flocculant is polymerized from: a) At least 5 mole % of a cationic monomer of formula (I); dialllyldialkyl ammonium halides or a monomer of formula II. In the compounds of formula I and II: R1 is H or CH3, R2 and R3 are independently CH3 or CH2CH3, A1 is O or NH, B1 is CH2CH3, CH2CH2CH3 or a hydropropoxy group, X1- is an anionic counterion, R4 is H or CH3, R5 and R6 are independently CH3 or CH2CH3, R7 is H, CH3 or CH2CH3, A2 is O or NH; B2 is CH2CH3, CH2CH2CH3, CH2CH2CH2CH3 or hydroxypropyl, and X2- is an anionic counterion. b) At least 5 mole % of a monomer selected from the group consisting of C1-C10 N-alkyl acrylamide, C1-C10 N,N-dialkyl arylamide, C1-C10 N-alkylmethacrylamide, C1-C-10 N,N-dialkylmethacrylamide, N-aryl acrylamide, N,N-diaryl acrylamide, N-aryl methacrylamide, N,N-diaryl methacrylamide, N-arylalkyl acrylamide, N,N-diarylalkyl acrylamide, N-arylalkyl methacrylamide, N,N-diarylalkyl methacrylamide, acrylamide and methacrylamide. The stabilizer polymer is a cationic polymer which is at least partially soluble in the aqueous solution of the anionic salt, where the addition of the water-soluble cationic flocculant polymer dispersion to the waste water is at a concentration of at least twenty-five weight percent polymer dispersion in water.