THE CLAKIFICATION OR DEFECATION OF THE JUICE. 



surface and are removed without breaking them up. The temperature is 

 kept constant by an ingenious thermostatic device ; cold water circulates in a 

 coil of oopper following the curve at the bottom of the clarifier. As this 

 water is heated it expands, and when the temperature becomes too great the 

 expansion operates the lever of a throttle valve admitting steam to the double 

 bottom and shuts off the supply. 



8. A type of automatic clarifier due to Hatton 2 is shown in Fig. 1J$. 

 The cold limed juice flows through the pipe a and the regulating valve b r 

 entering the defecator by the pipe c. As the defecator fills up, the juice over- 

 flows and fills the vessel d, which is closed at the bottom ; hence the juice 



U 



FIG. 142. 



passes upwards through the pipe e and away by the pipe /in to the clear juice 

 conduit and thence to the evaporators. 



The scums collect on the surface of the juice and are removed from time 

 to time ; it is claimed that these contain so little sugar that filter pressing is 

 unnecessary. The heat necessary is obtained by passing steam into the double 

 bottom ; heavier particles which settle are disturbed by occasionally rotating 

 the scraper and are then stated to be carried upwards to the floating layer of 

 precipitated material. The amount of steam entering, and consequently the 



243 



