13. Aspen Plus uses RADFRAC with the Tray Rating option to do detailed heat- and mass...

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13. Aspen Plus uses RADFRAC with the Tray Rating option to do detailed heat- and mass transfer design calculations and tray and downcomer design. Start by setting up the problem below with RADFRAC. 1. We wish to distill 80.0 mol/s of a feed at 25°C and 15.0 atm. The feed is 0.100 mole fraction ethane, 0.300 mole fraction propane, 0.500 mole fraction n-butane, and 0.100 mole fraction n-pentane. The column operates at 15.0 atm, has a partial condenser, and produces a vapor distillate. A kettle type reboiler is used. Our goal is to design a column using mass transfer rate analysis that will have a maximum n-butane mole fraction in the vapor distillate of YD,C4,max = 0.00875 and a maximum mole fraction of propane in the liquid bottoms of XBot, C3,max = 0.005833.- Preliminary analysis with an equilibrium model using the Peng-Robinson VLE was done in Lab 10. Because the flow rate in Lab 10 was significantly higher, the diameter was scaled to the reduced feed rate by using the ratio Dia Col2 = Dia col Coll After doing this scaling, Lab 10 shows that the following variables are a reasonable starting point: N (Aspen notation) = 35 and the feed on stage 16. Reflux ratio is L/D = 2.5, and Distillate flow rate = 32.0 mol/s. The column has two sections, section 1 is stages 2 to 15 and section 2 is stages 16 to 34. Each section has one pass. For initial diameters use Dia₁ = 1.36 m and Dia2 = 1.745 m. In both sections use sieve plates with the Fair flooding calculation method with flooding at 70%. Choose tray spacing 0.60 m, weir height = 0.0508 m, hole diameter = 0.0127 m, fraction sieve hole area to active area = 0.12, and downcomer clearance = 0.0381 m. Leave other variables in Tray Rating blank, which uses the default numbers for the variables in both sections. 13. Aspen Plus uses RADFRAC with the Tray Rating option to do detailed heat- and mass transfer design calculations and tray and downcomer design. Start by setting up the problem below with RADFRAC. 1. We wish to distill 80.0 mol/s of a feed at 25°C and 15.0 atm. The feed is 0.100 mole fraction ethane, 0.300 mole fraction propane, 0.500 mole fraction n-butane, and 0.100 mole fraction n-pentane. The column operates at 15.0 atm, has a partial condenser, and produces a vapor distillate. A kettle type reboiler is used. Our goal is to design a column using mass transfer rate analysis that will have a maximum n-butane mole fraction in the vapor distillate of YD,C4,max = 0.00875 and a maximum mole fraction of propane in the liquid bottoms of XBot, C3,max = 0.005833.- Preliminary analysis with an equilibrium model using the Peng-Robinson VLE was done in Lab 10. Because the flow rate in Lab 10 was significantly higher, the diameter was scaled to the reduced feed rate by using the ratio Dia Col2 = Dia col Coll After doing this scaling, Lab 10 shows that the following variables are a reasonable starting point: N (Aspen notation) = 35 and the feed on stage 16. Reflux ratio is L/D = 2.5, and Distillate flow rate = 32.0 mol/s. The column has two sections, section 1 is stages 2 to 15 and section 2 is stages 16 to 34. Each section has one pass. For initial diameters use Dia₁ = 1.36 m and Dia2 = 1.745 m. In both sections use sieve plates with the Fair flooding calculation method with flooding at 70%. Choose tray spacing 0.60 m, weir height = 0.0508 m, hole diameter = 0.0127 m, fraction sieve hole area to active area = 0.12, and downcomer clearance = 0.0381 m. Leave other variables in Tray Rating blank, which uses the default numbers for the variables in both sections.

Answer rating: 100% (QA)

Answer To set up the problem in Aspen Plus with RADFRAC we need to enter the appropriate parameters in the Tray Rating window The first section of par... View the full answer