Preparation of water-soluble polymers for flocculants with improved dewatering characteristics

David Hunkeler, Christine Wandrey
(Ecole Polytechnique Federale De Lausanne (EPFL), Switz.)., 2002
Brevet

Résumé

A process for prepg. a water sol. polymer comprises: providing a polymn. reaction mixt. comprising one or more polymerizable ethylenically unsatd. monomers; polymg. the ethylenically unsatd. monomers; and adding to the reaction mixt. during polymn. one or more chain branching agents (e.g., methylenebisacrylamide) either continuously or semi-continuously, the semi-continuous addn. further comprising at least two discrete addns. The polymers, typically acrylamide-based, have improved flocculating and dewatering properties. The polymer is useful in solid/liq. sepns. such as flocculants and coagulants in wastewater treatment applications, and as thickening agents. [on SciFinder (R)]

Official source

https://infoscience.epfl.ch/record/81284?ln=fr

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Polymer flocculants with improved dewatering characteristics

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(Ecole Polytechnique Federale De Lausanne (Epfl), Switz.).2002

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