Treatment of aqueous mineral suspensions with polymeric flocculants

A method of dewatering mature fine tailings comprising the steps of:

• i. adding to the mature fine tailings a poly(ethylene oxide) copolymer at a dosage level of about 600 ppm, wherein the poly(ethylene oxide) copolymer is (a) the reaction product of polymerizing 95 weight percent ethylene oxide and 5 weight percent 2-ethylhexylglycidyl ether to obtain a poly(ethylene oxide) copolymer with a dynamic viscosity of 8320 cP or (b) the reaction product of polymerizing 90 weight percent ethylene oxide and 10 weight percent 2-ethylhexylglycidyl ether to obtain a poly(ethylene oxide) copolymer with a dynamic viscosity of 6100 cP, the dynamic viscosity determined using a BROOKFIELD™ DV-II+ digital viscometer in a 1 weight percent solution of the poly(ethylene oxide) copolymer in a mixture of water and isopropyl alcohol in a weight ratio of about 6:1 at 25° C., and the polymerizing in the presence of a zinc alkoxide catalyst;
• ii. allowing the mature fine tailings and the poly(ethylene oxide) copolymer to flocculate;
• and
• iii. dewatering the mature fine tailings.