Distillation column C3 in Figure separates stream 5 into streams 6 and 7, according to the material balance in Table 1.5. A suitable column for the separation, if carried out at 700kPa, contains 70 plates with a condenser duty of 27,300,000 kJ/h. Using the following data and an infinite surroundings temperature, To, of 298.15 K, compute:

(a) The duty of the reboiler in kJ/h

(b) The irreversible production of entropy in kJ/h-K, assuming the use of cooling water at a nominal temperature of 25?C for the condenser and saturated steam at 100?C for the reboiler

(c) The lost work in kJ/h

(d) The minimum work of separation in kJ/h

(e) The second-law efficiency Assume the shaft work of the reflux pump isnegligible.

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Feed (Stream 5) Distillate Bottoms (Stream 6) (Stream 7) Phase condition Liquid 348 Liquid 323 Liquid 343 Temperature, K Pressure, kPa 1,950 700 730 17,000 Enthalpy. kJ/kmol 13,420 15,840 Entropy, 25.05 21.22 5.87 kJ/kmol-K Column 1 Column 2 Column 3 3 Deethanized feed C1 C2 C3 Component Ibmol/h C,H6 C3Hg iC,Hg nC,H10 iCgH12 nCsH12 0.60 57.00 171.80 227.30 40.00 33.60 205.30 735.70 Ce rich Ycnch Ibmol/h in Stream 3 4. iC4 nCa-rich Cs+-rich Feed to C3 Feed to C1 Feed to C2 C3 Component 0.00 0.00 0.60 0.00 0.60 С-Нь 0.00 0.60 2.20 2.20 0.00 54.80 C;Hy ICH10 NC4H10 iC,H12 nCsH12 57.00 0.00 57.00 8.60 162.50 0.60 171.10 171.70 171.80 0.10 226.60 10.80 215.80 0.00 226.60 227.30 0.70 28.10 0.00 28.10 0.00 11.90 28.10 40.00 17.50 0.00 17.50 0.00 33.60 16.10 17.50 0.00 0.00 0.00 0.00 Cs* 205.30 0.00 205.30 445.50 175.50 270.00 501.50 56.00 234.10 Total 735.60