Integration of Heat and Power

HEAT ENGINES RESERVIOR T1 Q1 W Heat Engine Q2 T2 RESERVIOR First Law of Thermodynamics W = Q1 - Q2 Second Law of Thermodynamics W  7c Q1 where 7c = T1 - T2 T1

HEAT PUMPS RESERVIOR T1 Q1 W Heat Pump Q2 T2 RESERVIOR First Law of Thermodynamics Q1 = W + Q2 Second Law of Thermodynamics W  7c Q1 where 7c = T1 - T2 T1

    F1(=QHmin) T heat source F2 Q F3 F4 W F5 Q - W (F6) heat sink PINCH F7 F8 F9 F10    = F1 + Q H Fn+1(=QCmin) = Fn+1 + Q - W C

  T F2 F3 F4 F5 (F6) PINCH F7 F8 F9 F10 Fn+1 = Q H = Fn+1 C HEAT ENGINE O W cold utility T (Q-W)=F1 F2 hot utility F3 F4 F5 (F6) PINCH F7 F8 F9 F10   Fn+1 = Q H = Fn+1 C

   T F2 F3 F4 F5 (F6) PINCH F7 F8+(Q-W) F9+(Q-W) F10+(Q-W) O F2 F3 F4 F5 HEAT ENGINE (F6) PINCH W F7 F8+(Q-W) F9+(Q-W) F10+(Q-W)   Fn+1+(Q-W) = F + Q H = Fn+1 + Q - W C

  T F2 F3 F4 F5 (F6) PINCH F7 F8 F9 F10 = F1 H = Q - W C F1 O = Fn+1 F7 F8 F9 F10 = F1 H   = Q - W C O = Fn+1 HEAT ENGINE (d) W (Q-W)

  T F2 F3 F4 F5 (F6) PINCH F7 F8 F9 F10 : Q + Q H : Fn+1 + (Q - W) (Q-W) = F1 T F2 F3 F4 F5 (F6) PINCH F7 F8 F9 F10 : Q + Q H   : Fn+1 + (Q - W) C (Q-W) Fn+1 (a)

  ZERO FLOW T X1 F2 = 0 X2 F3 = 0 X3 F4 = 0 X4 F5 = 0 X5 (F6) PINCH Q ZERO FLOW W T X1 F2 = 0 X2 F3 = 0 X3 F4 = 0 X4 F5 = 0 X5 (F6) PINCH (= F1 in (a)) F7 F8 F9 F10 : Q H   : Fn+1 C Fn+1 (b)

  F1 - W T F2  W F3  Q F4  Q F5 (F6) PINCH F7 F8 F9 F10 IN Q + W F3  Q F4  Q W Q HEAT PUMP F5 (F6) PINCH F7 F8 F9 F10 IN : F1 - W + W   OUT : Fn+1 Fn+1 (b)

  F1 T F2 F3 F4 F5 (F6) PINCH F7 F8+Q+W F9+Q+W F10 + W IN : F1 + W F7 Q + W F8+Q+W F9+Q+W W Q HEAT PUMP F10 + W IN : F1 + W   OUT : Fn+1 + W Fn+1 + W (b)

  F1 -(Q+W) T F2 -(Q+W) F3 -(Q+W) F4 -(Q+W) F5 -(Q+W) (F6) PINCH W Q HEAT PUMP F7  Q F8  Q IN : F1 - (Q+W) = F - Q F9  Q OUT : Fn+1 - Q F10  Q   Fn+1 + W (c)

Complex Distillation Configurations

(a) A A B C A B C B B C B C C Figure 5.1 The direct and indirect sequences of simple distillation columns for a three-component separation. (From Smith and Linnhoff, Trans. IChemE, ChERD, 66: 195, 1988; reproduced by permission of the Institution of Chemical Engineers.)

(b) A B A A B C A B C A B B C Figure 5.1(續) The direct and indirect sequences of simple distillation columns for a three-component separation. (From Smith and Linnhoff, Trans. IChemE, ChERD, 66: 195, 1988; reproduced by permission of the Institution of Chemical Engineers.)

A A B C B (Vapor Sidestream) C (a) More than 50% middle component and less than 5% heaviest component. Figure 5.10 Distillation columns with three products. (From Smith and Linnhoff, Trans. IChemE, ChERD, 66: 195, 1988; reproduced by permission of the Institution of Chemical Engineers.)

A A B C B (Liquid Sidestream) C (b) More than 50% middle component and less than 5% lightest component. Figure 5.10(續) Distillation columns with three products. (From Smith and Linnhoff, Trans. IChemE, ChERD, 66: 195, 1988; reproduced by permission of the Institution of Chemical Engineers.)

Partial Condenser A A B A B C B B B C Partial Reboiler C (a) Sequence for three product separation using nonadjacent keys (b) Figure 5.11 Choosing nonadjacent keys leads to the prefractionator arrangement.

Partial Condenser A A B A B C B B C Partial Reboiler C (a) (b) Prefractionator arrangement Figure 5.11(續) Choosing nonadjacent keys leads to the prefractionator arrangement.

A A B C A B C B B C B C C COLUMN 1 COLUMN 2 Figure 5.12 Composition profiles for the middle product in the columns of the direct sequence show remixing effects. (From Triantafyllou and Smith, Trans. IChemE, part A, 70: 118, 1992; reproduced by permission of the Institution of Chemical Engineers.)

COLUMN TOP COLUMN 1 COLUMN 2 RE-MIXING IN COLUMN 1 COLUMN BOTTOM Mole Fraction of B 1.0 Figure 5.12(續) Composition profiles for the middle product in the columns of the direct sequence show remixing effects. (From Triantafyllou and Smith, Trans. IChemE, part A, 70: 118, 1992; reproduced by permission of the Institution of Chemical Engineers.)

Partial Condenser A A B C B Partial Reboiler C Figure 5.13 Composition profiles for the middle product in the prefractionator arrangement show that there are no remixing effects. (From Triantafyllou and Smith, Trans. IChemE, part A, 70: 118, 1992; reproduced by permission of the Institution of Chemical Engineers.)

COLUMN TOP MAIN COLUMN PREFRACTIONATOR COLUMN BOTTOM 1.0 Feed Sidestream Stage Bottom PREFRACTIONATOR COLUMN BOTTOM 1.0 Mole Fraction of B Figure 5.13(續) Composition profiles for the middle product in the prefractionator arrangement show that there are no remixing effects. (From Triantafyllou and Smith, Trans. IChemE, part A, 70: 118, 1992; reproduced by permission of the Institution of Chemical Engineers.)

Figure 5.14 Thermal coupling of the direct sequence. B 1 2 3 4 A B C C (a) Thermally-coupled direct sequence (b) Figure 5.14 Thermal coupling of the direct sequence.

Figure 5.14(續) Thermal coupling of the direct sequence. B 1 2 4 3 A B C C (a) (b) Side-rectifier arrangement Figure 5.14(續) Thermal coupling of the direct sequence.

Figure 5.15 Thermal coupling of the indirect sequence. 2 3 4 A B C B C (a) Thermally-coupled indirect sequence (b) Figure 5.15 Thermal coupling of the indirect sequence.

Figure 5.14(續) Thermal coupling of the indirect sequence. 3 2 1 A B C 4 B C (a) (b) Side-Stripper arrangement Figure 5.14(續) Thermal coupling of the indirect sequence.

Partial Condenser A A B C B Partial Reboiler C (a) Prefractionator arrangement (b) Figure 5.17 The thermally coupled prefractionator can be arranged in a single shell.

A Main Column A B C B C (a) (b) Thermally coupled prefractionator(Petlyuk Column) Figure 5.17(續) The thermally coupled prefractionator can be arranged in a single shell.

A Main Column A B C B (b) (C) Dividing wall column C Figure 5.17(續) The thermally coupled prefractionator can be arranged in a single shell.

T A A B C  B C2 C1  C H Figure 5.18 Relationship between heat load and level in simple and prefractionator sequences. (From Smith and Linnhoff, Trans. IChemE, ChERD, 66: 195, 1988; reproduced by permission of the Institution of Chemical Engineers.)

T A A B C   B C2 C H Figure 5.18(續) Relationship between heat load and level in simple and prefractionator sequences. (From Smith and Linnhoff, Trans. IChemE, ChERD, 66: 195, 1988; reproduced by permission of the Institution of Chemical Engineers.)