An RO system consists of one pressure vessel with $6-$membrane elements in series as shown

Use the given data to calculate the required design variables:

Given Data

Feed Salinity $=38600m\frac{g}{L}$

Feed pressure $=68$ bar

Permeate pressure $=1$ bar

Pressure loss per element $=\frac{0\mathrm{.}18}{b}ar$

Recovery per element $=10\%$

Salt rejection $=99\mathrm{.}7\%$

Max applied pressure $=83$ bar Max.

Feed flow rate $=330\frac{m^3}{d}$ Max.

Permeate flow rate $=29\frac{m^3}{d}$ Min

Brine flow rate $=80\frac{m^3}{d}$

Required Design Variables

Feed, Permeate and Brine flow rates for each element

Feed, Permeate and Brine Salinities for each element

Net Driving Pressure of each element

Total pressure drop in the system

Total Feed flow rate of the system

Total Permeate flow rate of the system

Total Brine flow rate of the system

Total Recovery of the system

The average salinity of the permeate