MANUFACTURE OF MILK PowpER 285 
supply regulating feed (I}) which keeps the milk in the vacuum 
casing at a constant level, an overflow aperture (]) that regulates 
the thickness of the film, a vacuum pump, a scraper (S) to 
remove the film of dried milk from the revolving drum and an 
evacuated receiver (13) for the dried substance 
‘The milk is drawn into the drum casing or vacuum chamber 
by the force of the vacuum a this chamber. Tv the proper 
adjustment of the feed valve and the overflow valve, the milk 
rises to a given level and stays at that level while operation is 
in’ progress. «The revolving steam-heated drum | slightly 
dips into the milk in the vacuum chamber and picks up a film 
of milk which dries under reduced pressure while the drum 
makes one revolution. ‘Phe dried film is removed by the auto- 
matic scraper and the finished dried milk is discharged into the 
receiver, while the moisture-laden air and vapors escape through 
a condenser located outside of the drying apparatus. 
The Ekenberg Process.—Jhis is also a film drier operating 
in vacuo. This process was invented by Martin Ekenberg of 
Stockholm, Sweden, in the year 1899 and is covered by a number 
of United States patents, some of the earher of which are patent 
No. 764,995, 1904, and No. 785,600, March 21, 1905. The patents 
covering this process are owned by the Hien bars Company of 
Cortland, N. Y., who are operating numerous milk drying fae- 
tories in the States of New York and Michigan. 
The Ekenberge milk drier is called exsiccator. It consists 
of a revolving, steam heated nickel drum, inclosed in a vacuum 
chamber. ‘Phe ends of the drum form) bell-shaped bowls, 
dished outward. The drum is equipped with knives or scrapers, 
which remove the film cf dried milk that gathers on the drum. 
Attached to the vacuum chamber there is a smaller chamber 
which serves to receive the dried milk as it is scraped from the 
drum. ‘This is separated from the large vacuum chamber by a 
series of air locks, so that the material may be removed without 
breaking the vacuum in the large chamber 
The milk, as it enters the vacuum chamber, is sprayed into 
the concave ends of the drum. In this manner it is fore-con- 
densed. It is then withdrawn from the vacuum chamber by a 
pump, and returned again, this time being sprayed upon the 
