(Solved): A distillation unit consists of a partial reboiler, a bubble-cap column, and a total condenser. The ...

A distillation unit consists of a partial reboiler, a bubble-cap column, and a total condenser. The overall plate efficiency is 65%. The feed is a bubble-point liquid of 50 mol % benzene in toluene, which is fed to the optimal plate. The column is to produce a distillate containing 95 mol% benzene and a bottoms of 95 mol % toluene. Calculate for an operating pressure of 1 atm the: (a) minimum reflux ratio (L/D)min; (b) minimum number of actual plates; (c) number of actual plates needed for a reflux ratio (L/D) of 50% more than the minimum; (d) kg/h of distillate and bottoms, if the feed is 907.3 kg/h; and (e) saturated steam at 273.7 kPa required in kg/h for the reboiler using the enthalpy data below and any assumptions necessary. Enthalpy data for benzene and toluene: h? hy benzene 4,900 18,130 toluene 8,080 21,830 Equilibrium data for benzene and toluene at 1 atm: y 0.21 0.37 0.51 0.64 0.72 0.79 0.86 0.91 0.96 0.98 0.5 0.6 0.7 0.8 0.9 0.95 x 0.1 0.2 0.3 0.4