This type of apparatus is composed of a fairly long bundle of tubes topped
with a separator. The film of liquid is drawn through the tubes from the bottom
to the top by the evaporation vapour that is produced. The tubes are heated
from the shell side by steam, hot water or thermal fluids.
The original
Kestner apparatus, as it was patented in 1899, had tubes of seven meters long
and of various diameters, depending on the working conditions and the
characteristics of the processed liquids. This apparatus can be adapted in many
practical ways: lateral separator, one or more recirculation passes of liquids,
various diameters and lengths of tubes.
A: Product
B: Vapor
C: Concentrate
D: Heating
steam
E: Condensate