| 摘要 |
1428790 Removing solids from sugar liquors by flocculation and flotation TATE & LYLE Ltd 10 Sept 1974 [28 Sept 1973] 45516/73 Heading C6B Suspended solid impurities are removed from a sugar liquor, which is cane sugar evaporated juice or affination syrup, by a process comprising adding a water-soluble phosphate salt (e.g. a sodium orthophosphate) to the sugar liquor, to form a water-insoluble calcium phosphate primary floc containing suspended impurities; aerating the liquor containing the primary floc, with agitation; distributing uniformly throughout the aerated liquor from 1 to 40 parts by weight of anionic flocculating agent per million parts by weight of sugar in the liquor, to initiate the formation of a secondary floc therin, the flocculating agent being a polymer with a molecular weight of from 1 to 10 million containing from 50 to 80 mole per cent of acrylamide units and from 50 to 20 mole per cent of acrylic acid and/or acrylate units; retaining. the resulting mixture for from 15 seconds to 5 minutes in a flocculator vessel, with non-turbulent agitation preventing the segregation of the secondary floc from the liquor and allowing the secondary floc to grow; transferring the liquor containing the secondary floc without further agitation from the flocculator vessel to a separator vessel; allowing the secondary floc to segregate by flotation from the liquor in the separator vessel; and separately removing clarified liquor and flocculated solids from the separator vessel. Preferably the phosphate salt is added in an amount corresponding to from 100 to 600 parts by weight of P 2 O 5 per million parts by weight of sugar in said liquor and from 1 to 20 parts by weight of flocculating agent are used per million parts by weight of sugar in the liquor. |
