88 



the "2Oth Century" (See Fig. 30), which is sold as a pasteurizer 

 under the name of "Farrington," having cooling disks in another 

 compartment, while the "Miller," which I show with cooler at- 

 tached in Fig. 79, and the "Sturges & Burn" differ in using hot 

 water instead of steam, and in having the milk flow between two 

 revolving heating surfaces. Then we have the "regenerative" 

 heaters of which the Ahlborn is considered the best up-to-date. 

 The "regenerative" action is, that the cold milk cools the hot 

 while the hot milk heats the cold, and the great saving in heating 

 and cooling material (coal and ice) is thus evident. 



In Fig. 80 I show a cross-section of the apparatus. The cold 

 milk runs into the upper circular receptacle H on top of the pas- 

 teurizer and flows over the corrugated mantel A ; here it is heated 



by the warm milk inside the 

 mantel and is caught in the 

 annular trough B and led in- 

 to a small tank, not shown 

 in cut. This tank is connect- 

 ed with one of the most 

 "sanitary" pumps I ever saw 

 and the milk is forced 

 through the pipe C to the top 

 of the inner chamber in the 

 pasteurizer flowing over the 

 steam chamber D down the 

 inner side of the rotating 

 cylinder E and up between its 

 outside and the inner side of 

 the corrugated mantel A. 



A thermometer T is placed 

 at the point where the milk 

 has its maximum heat. The 

 milk is then discharged to 

 the cooler through the pipe 

 F. It is evident that the 



(Fiig. 80) 



milk when it leaves the apparatus must have equalized, or nearly 

 so, the temperature of the cold and hot milk, or to give an ex- 

 ample, if the hot milk at T is 160 degs. and the cold milk at H is 

 50 degs., then the milk at E will be about 105 degs. or just about 

 right for running through the separator. 



