| 摘要 |
The potassium content of aqueous liquors, e.g. a fermentation or distillation residue, is reduced by adding H2SO4, H2SO4 and a base other than a potassium base, or a sulphate of such a base, in a quantity, based on the potassium content of the liquor such that sulphating of the potassium occurs without precipitation of K2SO4, concentrating a minor fraction of the resulting solution to form crystal nuclei and increasing the size of these nuclei by progressive addition of the remainder of the treated solution thereto, in such a way as to maintain the concentration of potassium in the mother liquor at the desired value, followed by cooling the mixture of growing crystals and mother liquor. In one embodiment the minor fraction concentrated to provide nuclei is granulated by stock prior to addition thereto of the remaining liquor and concentration of the product under vacuum. The resulting liquor is further concentrated and cooled prior to separation of the K2SO4 crystals by centrifugation.ALSO:The potassium content of fermentation and distillation residues is reduced to render the liquor suitable for use in the preparation of cattle foods, by a process comprising adding H2SO4, or a water-soluble sulphate, or H2SO4 and a base not containing potassium, to the liquor in such quantity that sulphating of the potassium occurs without precipitation of K2SO4, then concentrating a minor fraction of the resulting treated liquor to form crystal nuclei and increasing the size of the said nuclei by progressive addition thereto of the remainder of the treated liquor, in such a way as to maintain the concentration of potassium in the mother liquor at a desired value, followed by cooling the mixture of crystals and liquor and separating the crystals from the liquor. |
