ANALYSIS, REPINING, AND COMPOSITION. 



33 



crude turpentine through valve 1 constant, whatever the level of 

 crude turpentine in D. The reservoir D having been filled and valve 

 10 closed, valve 1 is opened until the crude turpentine is running at 

 the required speed as registered on the speed indicator J, say 25 gal- 

 lons per hour. The crude turpentine then flows through the feed 

 heater C, where it is heated by steam from valve 2 to a temperature 

 of about 95 C., and enters the upper column A x at the fourth boiling 

 cap section as indicated. The steam supply is now adjusted by the 

 pressure regulator H 1? and the water in the reflux sections by valve 4, 

 so that the distillate leaving the top of column A is running at the 

 required speed as indicated on the speed indicator J 2 . The speed 

 required is determined from the analysis of the crude turpentines; 



FIG. 20. General arrangement of apparatus for refining crude turpentine. 



for instance, if 5 per cent of low-boiling material which it is desired 

 to remove from the refined turpentine is present in the crude, then 

 it is only necessary to adjust the speed of the first distillate to 5 per 

 cent of the speed of the crude. 



The portion of the crude not distilled in column A flows from the 

 bottom section through the trapped pipe 8 into the column A 2 at the 

 sixth boiling cap section. Here the distillation process is repeated 

 as in the top column, the water and steam supplies being adjusted 

 by valve 5 and the regulator H 2 , respectively, so that the distillate 

 leaves the top of A 2 at the required rate. 



The undistilled residue or " tails " runs out in liquid form from the 

 first boiling cap section, is cooled in the tails cooler I, separated from 

 58637 Bull. 10513 5 



