Process Equipment and Plant Design
In actual operation of distillation column, the vapour is not distributed uniformly among the bubble caps, primarily because of the

Lower skirt clearance
Liquid gradient on the tray
Small downcomer liquid seal
Lower static submergence

ANSWER DOWNLOAD EXAMIANS APP

Process Equipment and Plant Design
In a shell and tube heat exchanger, triangular pitch arrangement as compared to square pitch arrangement

Facilitates easier shell side cleaning; hence is more suitable for handling high dirt factor shell side fluid
Results in higher shell side pressure drop
Creates relatively lower turbulence on the shell side resulting in lower shell side heat transfer co-efficient
Can accomodate less number of tubes for a given shell diameter

ANSWER DOWNLOAD EXAMIANS APP