ENHANCED DEWATERING OF MINING TAILINGS EMPLOYING CHEMICAL PRE-TREATMENT

摘要

The invention relates to a process for separating solids from an aqueous slurry containing particulate material, which particulate material comprises sand particles and fines particles and contains clay particles, which aqueous suspension has a solids content of from 25 to 70% by weight and a sand to fines ratio of from 0.5:1 to 5:1, which process comprises applying a treatment system to the aqueous slurry to cause flocculation of the particulate material, and subsequently separating the so formed flocculated particulate material as solids from the slurry, in which the treatment system comprises (a) at least one ionic polymeric de-coagulant, which exhibits a weight average molar mass of below 2 million g/mol; (b) at least one polymeric flocculant, which has an intrinsic viscosity of at least 5 dl/g (measured at 25°C in 1 M NaCI) and (c) optionally, at least one cationic coagulant.