Process Equipment and Plant Design
Number of evaporators which can be used in service in a multiple effect evaporation system is limited by the

Economic limit reached, when the plant cost exceeds the saving of steam
Practical limit reached, due to low heat transfer rate because of inadequate temperature difference
Both A & B
Neither A nor B

ANSWER DOWNLOAD EXAMIANS APP

Process Equipment and Plant Design
Weep holes provided in the plates of a distillation column

Must be large enough (usually 1/4" to 5/8" dia) to prevent plugging but should not deliver excessive amount of fluid during operation
All of these
Are normally located near the overflow weir so that any delivery of liquid during operation follows approximately the same path as the overflow fluid
Facilitate draining out liquid from a tray when the unit is not in operation

ANSWER DOWNLOAD EXAMIANS APP