Dewatering aids
AssigneeKemira Oyj
InventorsMehrdad Hesampour, Matias Penttinen
Life of this patent
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Abstract
Disclosed are filter aids for use in industrial processes such as metal ore beneficiation dewatering and filtering processes, paper and pulp dewatering processes and sludge dewatering in municipal waste treatment. The filter aid provides increased filtering efficiency, and reduced filter cake moisture levels.
Claims17
Process for dewatering a slurry comprising the following successive steps:
- (i) contacting at least one filter aid composition comprising at least one anionic polystyrene sulphonate homopolymer having a molecular weight in the range 100 kDa-500 kDa with a slurry to be dewatered, at a dosage range of 10 to 500 g per ton of slurry to be dewatered, the slurry being a wet mineral ore slurry or a metal ore slurry;
- (ii) filtering said slurry by passing said slurry through a filter;
- and
- (iii) recovering a filter cake,
- wherein the anionic polystyrene sulphonate homopolymer has a viscosity ranging from 700-2300 cP determined using a Brookfield DV1 viscometer at 20° C., 30 rpm, and a spindle SC4-31, and
- wherein the anionic polystyrene sulphonate homopolymer does not lead to flocculation of the slurry being filtered.
A process for dewatering a slurry, which comprises treating the slurry with a filter aid comprising at least one anionic polystyrene sulphonate homopolymer having a molecular weight in the range 200 kDa-500 kDa, wherein the slurry dewatering process is a wet mineral ore dewatering process or a metal ore dewatering process, and wherein the filter aid is present at a dosage amount of 10-500 g per ton of slurry to be filtered,
- wherein the anionic polystyrene sulphonate homopolymer has a viscosity ranging from 700-2300 cP determined using a Brookfield DV1 viscometer at 20° C., 30 rpm, and a spindle SC4-31, and
- wherein the anionic polystyrene sulphonate homopolymer does not lead to flocculation of the material being filtered.
Dependencies are inferred from the claim text.