Task $1$:

Solve this problem by hand calculation.

Fresh blueberry juice contains an initial concentration of dissolved solids in

mass with the balance being water. It is to be processed to obtain a

concentrated sample with higher final concentration of dissolved solids for

easier transportation.

For that purpose, an initial process was evaluated where a feed of juice witl

is fed into an evaporator as a single process. However, for this initial

process, some volatile flavouring components were evaporated with the

water leaving the product with a modified taste.

The problem was overcome by bypassing the evaporators with a fraction of

the fresh blueberry feed and mixing with the evaporator product stream to

get a final product of required concentration with improved flavour.

$($a$)$ Draw and label a process flow diagram to represent the improved

process, neglecting the evaporation of volatile components with the

water $($assume the stream is purely water$).$

$($b$)$ Apply balance boxes and calculate the degree of freedom analysis

for each balance box. For example, demonstrate that the balance

box where the feed stream is split and bypassed from the evaporato

has a degree of freedom of $1.$

$($c$)$ Write the order of equations that will be used to determine all

unknown variables.

$($d$)$ Calculate the amount of final product produced per $100k\frac{g}{h}$ of fresh

juice fed to the process and the fraction of the feed that bypasses th

evaporator.

$($e$)$ As most of the volatile components that affect the flavour of the

concentrated juice are contained in the fresh juice that bypass the

evaporator, another improvement to the process would be increase

the amount of water from the evaporator to increase the juice

concentration to $90\%,$ you could then bypass a greater fraction of

fresh juice to get better taste of the product. Discuss possible

drawbacks of this proposal and support your answer.

Task $2$