Tugas II

Perhitungan Utilitas (asumsi onstream factor = 0.95)

a. E-101, Feed Preheater

Duty : 15.19 GJ/h

Cost of High-Pressure Steam = $17.70/GJ

Yearly Cost = (Q) (Csteam) (t) = (15.19 GJ/h) ($17.70/GJ) (24) (365) (0.95) = $2,237,000/y

b. E-102, Reactor Effluent Cooler

Duty : 46.66 GJ/h

Cost of Cooling Water = $0.354/GJ

Yearly Cost = (Q) (Ccw) (t) = (46.66 GJ/h) (24) (365) (0.95) ($0.354/GJ) = $137,000/y

c. E-103, Tower Feed Heater

Duty : 1.055 GJ/h

Cost of Low-Pressure Steam = $13.28/GJ

Yearly Cost = (Q) (Csteam) (t) = (1.055 GJ/h) ($13.28/GJ) (24) (365) (0.95) = $116,594/y

d. E-104, Benzene Condenser

Duty : 8.335 GJ/h

Cost of Cooling Water = $0.354/GJ

Yearly Cost = (Q) (Ccw) (t) = (8.335 GJ/h) ($0.354/GJ) (24) (365) (0.95) = $24,554/y

e. E-105, Product Cooler

Duty : 1.085 GJ/h

Cost of Cooling Water = $0.354/GJ

Yearly Cost = (Q) (Ccw) (t) = (1.085 GJ/h) ($0.354/GJ) (24) (365) (0.95) = $3,196/y

f. E-106, Benzene Reboiler

Duty : 9.045 GJ/h

Cost of Medium-Pressure Steam = $14.19/GJ

Yearly Cost = (Q) (Csteam) (t) = (9.045 GJ/h) ($14.19/GJ) (24) (365) (0.95) = $1,068,116/y

g. H-101, Feed Heater

Duty : 27 GJ/h

Assume thermal efficiency 90%

Cost of Natural Gas = $11.10/GJ

Heating Value = 0.0377 GJ/m3

Yearly Cost = (27 GJ/h) (11.10/GJ) (24) (365) (0.95)/(0.90) = $2,771,000/y

h. C-101, Recycle Gas Compressor

Shaft Power = 49.1 kW

Electric drive efficiency = 90% (Figure 8.7)

Electric Power = Pdr = Output power/efficiency = (49.1)/(0.90) = 54.6 kW

Yearly Cost = (54.6) (0.06) (24) (365) (0.95) = $27,200/y

i. P-101, Toluene Feed Pumps

Shaft power = 14.2 kW

Electric drive efficiency = 86% (Figure 8.7)

Electric Power = 14.2/0.86 = 16.5 kW

Yearly Cost = (16.5) (0.06) (24) (365) (0.95) = $8,240/y

Capital Related Cost