CAKE SUGAR. 



the decreased quantity of non-sugar the actual loss of sugar is not increased ; 

 in addition carbonation molasses are less viscous and lighter coloured, so that 

 they are more easily removed in the centrifugals. 



Later analyses of carbonation molasses published by Geerligs in " Cane 

 Sugar and its Manufacture " do not show a higher purity than do defecation 

 molasses; the average of eight carbonation factories and of sixty-seven 

 defecation factories are as under: 



Total 



Solids Polari- Sucrose Apparent True 



Brix. Percent, zation. Percent. Purity. Purity. Glucose. Gums. Lime 

 Garb... 83-7 .. 78'6 .. 31-1 .. 31'3 .. 37'1 .. 39-8 .. 21-6 .. -74 .. 1-38 

 Def. .. 85-4 .. 80-0 .. 28-8 .. 33'9 .. 33'7 .. 42'4 . 23'6 .. 1-95 .. '53 



It will be observed however that the difference between the polarization 

 and sucrose per cent, is much less in the carbonation molasses, than in the 

 defecation molasses ; this is of course to be correlated with Lobry-de-Bruyn's 

 and Yan Ekenstein's observations on the transformations of reducing sugars in 

 the presence of alkalies. 



Finally, Hazewinkel 3 in obtaining a formula for available sugar allows a 

 loss of 5 per cent, of sucrose in the carbonation process ; this would seem to 

 imply that the recovery of sucrose in this process is less than in the defecation 

 process, and is to be ascribed to the action of the lime in large quantity on the 

 sucrose. 



Details Of Routine. It remains to describe the practice of the pro- 

 cess, which may be varied in details to suit the requirements of different 

 factories or the ideas of different manufacturers. In the single process, the 

 juice is received as usual in tanks, where it is treated with from 10 per cent, 

 to 20 per cent, of milk of lime, standing at 20 Brix. Attempts made to intro- 

 duce the lime in a dry state have not been successful, but to prevent the 

 considerable dilution that would be necessary if the lime were mixed with 

 water, the dilute washings from the filter presses have been substituted. But it 

 has been found that a badly filtering juice thereby results. The carbonation 

 may be performed in the vessels in which the juice is received, or the limed 

 juice may be run off into special tanks ; the exact amount of lime added not 

 being a matter of importance, the use of liming tanks is not essential. 



In the double process, the first carbonation is performed in the vessels 

 in which the lime is added, after which the juice is filtered en masse or else 

 decanted and the scums only filtered. The cleared first carbonation juice is 

 then passed on to the saturation or second carbonation tanks where the process 

 is finished as already indicated. 



It is general to keep the scums from the two carbonations entirely 

 separate, but in some beet sugar factories it is the custom to mix and filter 

 them together, a more easily treated material being thus obtained. This is a 



264 



