English: This is a diagram of a vertical submerged tube triple-effect evaporator, for concentrating sugar cane juice in the production of cane sugar.

The three vessels are each fitted with a calandria that allows steam fed in through pipes labelled b to condense against tubes that connect upper and lower chambers, which all contain the juice to be concentrated (fed in through pipes labelled a).

The chambers are kept at successively lower pressures, so that the steam that boils off the juice in the previous chamber can be used to further boil the more concentrated juice in the next chamber.

Condensation is pumped out through pipes labelled c, and steam that does not condense in the second calandria can be fed forward through pipes labelled d. The pipe labelled e is described as a washout pipe.