THE CONCENTRATION OF THE SYRUP TO MASSECUITE. 



Crystallization in Motion of Low Products. In some 

 factories it is customary to cool in motion the low massecnites only after one or 

 two lots of crystals have been obtained. In such cases the massecuites are 

 usually allowed to stand until grain has begun to appear when they are 

 subjected to a stirring which is continued for about a week ; from this product 

 a low sugar is obtained which usually is not marketed directly but is remelted 

 and refined in the factory. Except for economy in floor space and for the 

 saving of money lying idle, this process has nothing to recommend it ; it is 

 much inferior in results to the processes described above ; its chief application 

 lies in factories which make a high grade white sugar where the addition of 

 molasses to the syrup is inadvisable. 



Time for Cooling. The strikes of higher purity are usually cooled 

 for 12-15 hours; those of lower purity whence exhausted molasses are 

 expected are cooled from 48-72 hours. 



Crystallizer Capacity. -For a complete separation of massecuites 

 into sugar and waste molasses 20 cubic feet of crystallizer capacity are required 

 per long ton of sugar per week ; less may serve but no margin is then allowed 

 for the miscarriages which occasionally happen. 



Technique of Crystallization in Motion. This process gives 

 great opportunity for observation and craft skill ; some points are mentioned 

 below. 



Before taking molasses into the pan they should be cleaned by boiling in 

 an eliminating pan and the scum which rises to the surface skimmed off ; this 

 heating will also dissolve fine grain. 



The size of the pans and crystallizers should be correlated, so that a 

 crystallizer takes a full or half charge of a pan. 



For convenience of working all pans and tanks should be graduated, so 

 that the operators can know exactly what quantities of syrup and molasses are 

 in progress. During the process of cooling the massecuites should be inspected 

 frequently and if they become too thick, hot exhausted molasses may be 

 added as a diluent ; an experimental centrifugal is very useful in following up 

 the cooling process. 



The stirrers should be completely immersed in the massecuites, else in 

 their rotation they will force air into the massecuite which will form an 

 emulsion and may make the molasses so light that they will not pass 

 through the wall of sugar in the centrifugal baskets. 



Control of the Water Content of Massecuites.* It has 



been shown above that the success of these schemes depends on a knowledge 

 of the water content of the massecuite when it is struck from the pan ; this 



* See Note in Appendix. 

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