to the heating calandria of the third cell under a vacuum of approximately 

 15 inches the vapors are hot enough to boil the juice in the third cell and 

 the vapors from this cell passing to the fourth cell calandria under a vacuum 

 of approximately 26 inches, bring the final boiling down to a temperature 

 of about 150. Therefore, we have had four successive boilings of juice, re- 

 ducing the temperature in each cell without adding any additional live steam. 

 Vacuum gauges are fitted to each cell of the evaporator so that the operator 

 may at all times know the vacuum carried. Test tubes are also fitted to the 

 syrup side of the evaporator to permit the operator at any time to test the 

 density. In maintaining a vacuum on this apparatus a vacuum pump is 

 required in addition to a supply of cold water. The vapors passing to the 

 condenser come in contact with the cold water and are condensed, the air and 

 non-condensable gases being drawn off through the vacuum pump. 



Vacuum 

 Pans 



Concentration and Crystallization 



The evaporator discharges the syrup into a syrup tank from 

 which it is pumped to the highest floor of the factory building 

 or what is known as the vacuum pan floor. A series of tanks are 



Vacuum Pans w here sugar crystals are formed 

 43 



