Environmental Engineering Reference
In-Depth Information
facility needs with the minimum utility needs calculated before to define the gap needed to be
tackled. This step will help us evaluate potential savings upon the heat integration for certain
process area.
C
ONSTRUCTING THE
G
RAND
C
OMPOSITE
C
URVE
(G.C.C)
This curve will be drawn between T* calculated before during the temperature interval
diagram construction which is the average temperature of hot and cold side each interval
boundary and the corresponding surplus heat/enthalpy from each interval.
These data are shown below for a generic balanced cascade diagram that can be
developed for any application as shown before:
Data Required To Construct The G.C.C
T* (K)
Enthalpy ( kW)
2620 kW
555
1
T* (K)
515
1860 kW
2
385
690 kW
3
375
580 kW
4
310
280 kW
5
305
0.0 kW
Thermal Pinch
6
295
50 kW
Enthalpy ( kW)
Figure 14. Data required to drawing Grand Composite Curve (G.C.C.)
Drawing these data as T* versus Enthalpy results in the following diagram that can be
used to define different levels of utilities mix that can be used to satisfy the process heating
utility requirement for instance, as shown below.
