GB666781A - Method of purification of sugar juices - Google Patents

Abstract

666,781. Purifying sugar solutions. AKTIEBOLAGET SEPARATOR. Nov. 26, 1948 [Nov. 26, 1947], No. 30726/48. Class 127. [Also in Group II] Sugar juices are purified by adding chemicals to change their pH and precipitate organic impurities, filtering with filter aids which with the impurities, both organic and inorganic, form a sludge which is removed from the juices, removing the main part of the organic impurities from the sludge in a centrifuge and returning the treated sludge wholly or in part for reuse. In operation, sugar beets are washed, sliced and the slices treated with counterflowing liquid in a diffusor batterv 3-7. The slices are strained in a device 8 the water therefrom being returned to the diffusor battery. The slices are pulped in a press 9, the expressed liquid treated with acid and passed to a sedimentation apparatus 11- the separated water being also returned to the diffusors. The sludge is concentrated in a separator 12 and transferred to a drier 10 wherein the pulp from the press 9 is also dried. The raw sugar juice leaves the diffusor 3 and is treated with lime in a container 13 for optimal precipitation. A further lime treatment is given in a container 14 and then followed by a carbon dioxide treatment whereby calcium carbonate is precipitated into the organic impurities precipitated in the container 13. Separation of the juice from the precipitate is effected in separators 16 or 16a, but the separated juice is further treated with carbon dioxide in a container 17 to precipitate more lime, and passed to a filter 18. The sludge so obtained is mixed in a mixer 19 with that from the separators and filtered in a filter 20. The juice therefrom mixes with the juice from the filter 18 is saturated with carbon dioxide in a container 21 to precipitate the remaining lime and filtered on a filter 22, the juice thereby obtained being suitable for concentration by evaporation. The sludge obtained from this filter 22 is returned to the mixer 19 and serves as a filter aid in the filter 20. The sludge from the filter 20 is mixed with water and fed to the centrifugal separator 23 in which the filter aid is separated from the organic impurities and returned to the mixer 19. This organic component is returned to the sedimentation apparatus 11.