Question

Orange juice concentrate is made by concentrating single-strength juice to 65% solids followed by dilution of the concentrate to 45% solids using single-strength juice. Draw a diagram for the system and set up mass balances for the whole system and for as many subsystems as possible.

Answer 1

Consider a hypothetical proportionator that separates the original juice (S) to that wich is fed to the evaporator (F) and that (A) wich is used to dilute the 65% concentrate. Also, introduce a blender to indicate that part of the process where the 65% concentrate (C₆₅) and the single-strength juice are mixed to produce the 45% concentrate (C₄₅).

The material balance equations for the whole system and the various subsystems are:

Overall: S= W +C₄₅

Proportionator: S = F + A

Evaporator: F = W + C₆₅

Blender: C₆₅ + A = C₄₅

And the diagram goes like this.

Hope the answer works for you!