CANE SUGAR. 



Control of the Boiling House. The basis of this is the amount 

 of available tugar in the mixed juice, i.e., that quantity of sugar which can he 

 obtained from that expressed by the mills. 



In times past a number of irrational formula? based on the percentage of 

 glucose and of ash have been proposed ; the first rational one is that due to 

 Winter who from a study of actually recorded results in Java concluded that 

 one part of non-sugar prevented '4 part of sugar crystallizing ; expressed 

 algebraically this observation appears 



Available sugar = S x f 1*4 p . j 



where S is the amount of sugar in the raw juice. In this formula the available 

 sugar refers to the gross weight of the commercial product. 



The writer treats the matter as follows : 



In unit weight of a juice after removal of water let there be a parts of 

 sugar and b parts of non-sugar. Now let c parts of sugar be removed as in the 

 process of manufacture so that the residue (molasses) now is 1 c ; let 1 c 

 contain d parts of sugar per unit weight. Since the total amount of sugar was 



0, the equation a = c + (1 c\ d results. Whence =, -. 



a a (I d) 



Now is the proportion of sugar that has been removed and for a, which 



is the proportion of sugar in dry material, the purity of the juice may be 

 written and for d the purity of the molasses. 

 The expression then becomes 



Proportion of Sugar \ 



<, T, , ,. I purity juice purity molasses .; m 



removed or Extraction } = . ^ ; r A ; = ^7\ "x 



\ purity luicefl purity molasses) Jil m) 



of Sugar in Juice ) 



where/ and m are the purities of the juice and molasses. 



That is to say when the purity of juice and ipurity of molasses are known, the 



corresponding extraction of sugar per 100 sugar in juice can be calculated. 



The calculation above is an ideal one under conditions that are not reached 

 in practice, assuming as it does that pure sugar and not an impure product 

 containing a portion of the impurities is made ; the impurities contained in the 

 commercial sugar if replaced in the molasses would of course tend to lower 

 the actually observed purity of the molasses. The complete formula can be 

 obtained as follows : 



From a material containing a sugar and b non-sugar per unit weight, let 

 there be removed c sugar and d non-sugar and let (c + d) contain e sugar per 

 unit weight. The residue (molasses) is 1 c d and let it contain / sugar per 

 unit weight. 



Then a = ( c + d) e + (I - c - d) f or 



(*-/) 



or proportional gross weight of dry commercial _ j m 



sugar removed j ( m) 



where y and m are as before and s is the purity of the commercial product. 



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