E3.1

For the five-stream problem below (from Section 2.6), find the energy targets and pinch and plot composite curves and GCC if not done previously. What is the significance of the temperature range and CP of stream 3? What effect does this have on the pinch?

Stream

Supply temperature ( C)

Target temperature ( C)

Heat capacity flow rate CP (kW/K)

Heat load Q (kW)

Hot 1

200

50

3

450

Hot 2

240

100

1.5

210

Hot 3

120

119

300

300

Cold 4

30

200

4

-680

Cold 5

50

250

2

-400

E3.2

For the organics distillation unit in Section 3.8, calculate the airflows and fuel use for the vacuum furnace, assuming the same level of heat losses as for the atmospheric unit furnace, and the same temperatures for air and flue gas.Perform the targeting calculation for the vacuum unit with its furnace included, and for the combined units including both furnaces. Evaluate and rank the various options for energy reduction from integrating the utility systems.