A process fluid is pumped from the bottom of one distillation column to another, using a centrifugal pump. The line is standard commercial steel pipe 75 mm internal diameter. From the column to the pump inlet the line is 25m long and contains six standard elbows and a fully open gate valve. From the pump outlet to the second column the line is 250m long and contains ten standard elbows, four gate valves (operated fully open), and a flow-control valve. The fluid level in the first column is 4m above the pump inlet. The feed point of the second column is 6m above the pump inlet. The operating pressure in the first column is 1.05 bar(a) and that of the second column 0.3 bar(g). The physical properties of the fluid are: density 875 kg/m³, viscosity 1.46 mN/m²/s. a) Develop a system curve when the pressure drop across the control valve is 35 kN/m² (show full working and assumptions, marks awarded for working and for correct determination of static and dynamic losses) b) Using the system curve from part (a), determine the operating point on the pump curve below. c) Determine the NPSH, at this flowrate, if the vapor pressure of the fluid at the pump suction is 25kN/m². Head (m) 35 30 25 20 15 10 10 5 0 0 10 10 20 30 40 50 60 60 Flowrate (m3/h) 10 70