Improvements in the Process of Extracting Sugar from Beetroot and Sugar-cane Juices and other Fluids containing Sugar

摘要

21,985. Hlavati, F. Oct. 31. Purifying saccharine liquids and syrups.-During the defecation of sugar-cane, beet-root, and other saccharine juices, hydrofluosilicic acid or bydrofluoboric acid. neutralized by means of calcium hydroxide, is added to the juices during the usual treatment with lime ; oxidizing-agents, such as calcium peroxide, manganese peroxide, and hydrogen peroxide, may also be added. The saccharine juices are then saturated with carbon dioxide in the usual way, and filtered. In factories where the juice is treated three times with lime and carbon dioxide, the above-mentioned additions may be made during the second treatment. Vegetable matters, such as hay and grass, or preferably such as contain tannic or gallic acid, such as valonia, quebracho or sumac, may also be added to the juices. During the passage of the filtered juice into evaporating-apparatus, iron filings, zinc dust, zinc antimonide, zinc calcide, magnesium silicide, calcium carbide, aluminium sulphide, sulphide of phosphorus, phosphorous acid, hypophosphorous acid, or other suitable substance may be added ; or charcoal powder may be added, and an electric current passed through the juice during the evaporating process. Tbe concentrated and decolorized syrup may be run from the evaporating-apparatus into tanks, and treated successively with sulphur dioxide and sulphuretted hydrogen. The syrup is concentrated to the crystallization point, and the masse is finally machined. The green syrup from the centrifugal apparatus is added gradually to fresh juice which is being defecated.