Liming, sugar extract

Raw Sugar Extract Purification (liming and carbonatation). Juice purification results in the removal of 30—40% of the nonsugar substances and has the following objectives ... 

An enamel-lined rotary digester, which was heated by direct steam, was used for the hydrolysis in these investigations. The sugars produced by the hydrolysis were extracted from chips in an extraction battery. The sugar solution was neutralized with lime, filtered and then prepared for fermentation. 

In the initial stages of purification, sucrose is recovered in juice form by crushing cane stalks or by extraction of sliced sugarbeets (cossettes) with hot water. The resulting solutions are clarified with lime, then evaporated to thick syrups from which sugar is recovered by crystallization. The final syrup obtained after exhaustive crystallization of sucrose is known as molasses. Enhanced recovery of sucrose from beet molasses is accomplished by ion-exclusion chromatography, a process used in some sugar mills in the United States, Japan, Finland, and Austria. 

Seme years ago a method was patented by,Mr. Micuiel for extracting the sugar from cane without the nsa of the mill it was proposed to cut the canes into thin slices and treat them with lime water. The ooject of this was to render the nitrogenous constituents of the... 

The juice is further clarified by a liming step. Here the juice is preheated and mixed with Ca(OH)2 (lime milk) in the required ratio. This mixture is transferred into a settling tank (clarifier), where solid compounds are separated. By this procedure, clear juice is obtained. The mud from the clarifier stiU contains considerable amounts of valuable sugar. Therefore, the mud is filtered on rotary vacuum filters. This way, the residual sugar is extracted the mud is washed again, releasing sweet water that is united with the clear juice [61-63]. 

Strontium hydroxide, prepared mainly from the mineral sulphate, is largely used in the extraction of the uncrystallisable sugar from molasses. The native carbonate requires a higher temperature for calcination to oxide than does calcium carbonate to lime. However, in certain sugar works, where fuel, including exhausted cane, is cheap, this process is used for the production of the material. 

For the extraction of sugar the expressed juioe ia heated in large pans to about 100 F.) muk of lime is added, which causes t precipi-... 

The process of making sugar depends on the source from which it is extracted. With sugar cane, the plant stalks are crushed to obtain the sweet juice they contain. The juice is treated with lime to remove impurities and then boiled until the juice thickens into a syrup. Evaporation of the syrup produces crystals of sucrose. Juice remaining after the evaporation step is sold as molasses. Stalks remaining after the juice has heen extracted can he used as a fuel in the plant s boilers. 

Sugar is also extracted commercially from certain species of palm, from the sugar maple and from sweet sorghum. Lime is used to purify the extracts before evaporation. 

The second step is coloring. The local term used for this step is mbabar. The dye used is usually derived from a plant that is extracted through simple methods. Among others are indigo (Indigofera), sugar cane or molasses and lime or calcium oxide as additives. 

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