Page 267 - Sustainability in the Process Industry Integration and Optimization

244 Cha p te r T e n

this current problem. Wherever appropriate, suggest how
an option can be exploited.
(1) Flue gas heating
(2) Heat pumping
(3) Introduction of a new steam level

Problem 7: Solutions
Answer to (a). The heat recovery targets and the Pinch location can be obtained
with the help of the PTA. The heat cascade intervals and the corresponding
stream population are shown in Table 10.20, and the computed problem table
is given in Table 10.21.

Temperature boundary Interval number Stream population
180.1
1 H4
180.0
2
165.0
3 H3, C1
160.0
3 H1, H3, C1
155.1
4 H1, H3, C1, C2
155.0
5 H1, H3, C1, C3
115
6 H1, C1, C3
95.0
7 H1, C1, C4
85.0
8 H1, H2, C1, C4
65.0
9 H1, H2, C4
60.0
10 H2, C4
35.0
11 H2
25.0

TABLE 10.20 Heat Cascade Intervals and Stream Population for Problem 7(a)