The initial process in most refineries is a simple distillation in which the crude oil is...

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The initial process in most refineries is a simple distillation in which the crude oil is separated into various fractions. The flowsheet for one such process is illustrated in Figure. Make a complete material and energy balance around the entire distillation system and for each unit, including the heat exchangers and condensers. Also: Figure: 500 F Tower I Furnace 250°F 200°F Heat exchanger Storage residue 500,000 lb/day 90°F Overhead H₂0 Condenser H₂O 70°F I 120°F 480°F Bottoms Charge oil Overhead, tower I Bottoms, tower I Overhead, tower II Bottoms, tower II 180°F Steam Preheater 260°F Storage naptha 200,000 lb/day 90°F Specific Heat of Liquid Btu/(lb)(°F) 0.53 0.59 0.51 140°F 0.63 0.58 Tower II Overhead 150°F 100 111 92 118 107 Heat exchanger IV. Latent Heat of Vaporization Btu/lb H₂0 Condenser H₂O 70°F II 110°F H₂0 70°F Bottoms a. Calculate the heat load that has to be supplied by the furnace in British thermal units per hour. b. Determine the additional heat that would have to be supplied by the furnace if the charge oil were not preheated to 200°F before it entered the furnace. Storage charge oil 1,000,000 lb/day 90°F Do the calculated temperatures of the streams going into storage from the heat exchangers seem reasonable? Additional data: Heat H₂O exchanger E /80°F 120°F Storage gasoline 300,000 lb/day 90°F Specific Heat of Vapor Btu/ (lb)(°F) 0.45 0.51 0.42 0.58 0.53 Condensation Temp. °F 480 250 500 150 260 The reflux ratio of tower I is 3 recycle to 1 product. The reflux ratio of tower II is 2 recycle to 1 product. The reflux ratio is the ratio of the mass flow rate from the condenser to the mass flow rate that leaves the top of the tower (the overhead) and enters the condenser. The initial process in most refineries is a simple distillation in which the crude oil is separated into various fractions. The flowsheet for one such process is illustrated in Figure. Make a complete material and energy balance around the entire distillation system and for each unit, including the heat exchangers and condensers. Also: Figure: 500 F Tower I Furnace 250°F 200°F Heat exchanger Storage residue 500,000 lb/day 90°F Overhead H₂0 Condenser H₂O 70°F I 120°F 480°F Bottoms Charge oil Overhead, tower I Bottoms, tower I Overhead, tower II Bottoms, tower II 180°F Steam Preheater 260°F Storage naptha 200,000 lb/day 90°F Specific Heat of Liquid Btu/(lb)(°F) 0.53 0.59 0.51 140°F 0.63 0.58 Tower II Overhead 150°F 100 111 92 118 107 Heat exchanger IV. Latent Heat of Vaporization Btu/lb H₂0 Condenser H₂O 70°F II 110°F H₂0 70°F Bottoms a. Calculate the heat load that has to be supplied by the furnace in British thermal units per hour. b. Determine the additional heat that would have to be supplied by the furnace if the charge oil were not preheated to 200°F before it entered the furnace. Storage charge oil 1,000,000 lb/day 90°F Do the calculated temperatures of the streams going into storage from the heat exchangers seem reasonable? Additional data: Heat H₂O exchanger E /80°F 120°F Storage gasoline 300,000 lb/day 90°F Specific Heat of Vapor Btu/ (lb)(°F) 0.45 0.51 0.42 0.58 0.53 Condensation Temp. °F 480 250 500 150 260 The reflux ratio of tower I is 3 recycle to 1 product. The reflux ratio of tower II is 2 recycle to 1 product. The reflux ratio is the ratio of the mass flow rate from the condenser to the mass flow rate that leaves the top of the tower (the overhead) and enters the condenser.