CANE SUGAK. 



The same canes with double saturation in a twelve-roller 

 mill will give an extraction of 



And with compound saturation in a twelve -roller mill will 

 give an extraction of 



97-4 

 98-0 



The Effect of an inferior Dry Crushing. Instead of taking 

 45 per cent, of fibre in the dry crushed megass, let the percentage of fibre be 

 40 per cent. Then if the canes contain 12 per cent, of fibre, the extraction due 

 to dry crushing is 81-93 per cent, leaving 18-07 per cent, in the megass ; let 

 this megass after the addition of water be crushed to 50 per cent, of fibre . 

 below is calculated what will be the extraction with single maceration after 

 the addition of water 10 per cent., 20 per cent., &c., on cane, and for the pur- 

 pose of comparison the figures already obtained when the dry crushed 

 megass contains 45 per cent, of fibre are added. 



Water added per 100 cane. 



The advantage in favour of the more eifective dry crushing is in reality 

 greater than is shown in the above calculation ; complete admixture is in both 

 cases assumed; in practice we do not obtain complete admixture, but the 

 admixture will be the less imperfect the more the megass is disintegrated; 

 that is to say, when the fibre content is higher. 



The Economic Limit of Saturation. It is well known that 

 with each increment of extraction the purity and the amount of available sugar 

 per 100 sugar extracted also falls; if with an extraction a the proportion of 

 available sugar is #, and with an extraction of a 4- d the proportion of available 

 sugar is x e, it is easy to conceive a state where a x is greater than (a + d) 

 (x e) and where ( a x expenses) is greater than [_ (a -\- d) (x e) 

 expenses.] In order to put this conception to the test the writer crushed canes 

 with the addition of water in a hand mill till over 98 per cent, of the sugar 

 was obtained ; in all, eight fractions of juice were obtained, each one being 

 measuied and analysed separately; there was thus obtained the extraction at 

 eight points together with the available sugar; the available sugar was 



calculated from the . ^ _ ^ formula developed in Chapter XXF., giving to* 

 and m the values 97*5 and 45'0. 



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