Process Equipment and Plant Design
Liquid gradient over a tray can be minimised by

Decreasing the number of rows of caps through which the liquid flows or by decreasing the velocity of liquid flow past the caps or by reducing the distance along the tray through which the liquid must
All of these
Providing a higher skirt clearance or a higher weir
Using split flow, radial flow or cascade flow for column diameter large than 4 ft

ANSWER DOWNLOAD EXAMIANS APP

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

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

ANSWER DOWNLOAD EXAMIANS APP