170 Continuous Process EVAPORATORS 
milk in the tubes (160 feet per second or more) increases the 
capacity of the heating surface, and the small amount of milk 
in circulation, together with the low level of the milk in the 
tubes, reduces the possibility of foaming, confining the foam to 
and breaking it up in the upper part of the tubes where film 
evaporation takes place. 
The escape of the condensed milk is continuous and the 
VAPO.t OUTLET 
~COMDENSATION OyTLED 
SECTION 
\ Liquor OUTLET 
AnD DRAIN 
\ 
MANHOLE WITH OBSERVATION GLAssy 
WASH Wares i ae 
i 
Varog OUTLET STEAM Imier 
pees 
7 
C-. Conpensanon Ovrusy 
Pal 
Liquom Inet — 5 s 
& OBSERVATION GLAse 
PLAN 
Fig. 74. Cross section of Buflovak rapid circulation evaporator 
Courtesy of Buffalo Foundry and Machine Co. 
degree of concentration is controlled by a valve regulating the 
outlet. The condensed milk runs by gravity from the steam 
chest into a reservoir located under the evaporator. In this case 
the reservoir must be under the same vacuum as the evaporator. 
In some cases it is recommended to have an intermediate storage 
tank removing the condensed milk from the evaporator by a spe- 
cially constructed steam pump- 
