A continuous evaporator process is shown in Fig. Q$2$a$.$ The liquid feed is heated

by an external steam$-$fed reboiler.

$($a$)$ Show how the process could be fully controlled by creating a properly

annotated P&ID of the process using Fig. Q$2$a as a basis. You should aim

to specify four separate control loops.

$(12)$

$($b$)$ Briefly overview the rationale of operation of each control loop that you

have specified.

$(4)$

$($c$)$ The dynamic performance of one of the control loops under a step$-$change

in set$-$point occurring at $08$:$00$ is represented in Fig. Q$2$b$.$ The process

variable is shown as a percentage. For each of the performance metrics

below determine the numerical value and explain what the features of the

response the metric describes.

i$)$ Overshoot. $(3)$

ii$)$ Settling time. $(4)$

iii$)$ Time to first peak. $(2)$