Calculate the power required to drive the pump in Prob. 8.2 if the pump is to elevate the toluene 10 m, the pressure in the second unit is atmospheric, and the friction loss in the discharge line is 35 kN/m². The velocity in the pump discharge line is 2 m/s.

Problem 8.2

It is proposed to pump 10,000 kg/h of toluene at 114°C and 1.1 atm abs pressure from the reboiler of a distillation tower to a second distillation unit without cooling the toluene before it enters the pump. If the friction loss in the line between the reboiler and pump is 7 kN/m² and the density of toluene is 866 kg/m³, how far above the pump must the liquid level in the reboiler be maintained to give a net positive suction head of 2.5 m?