Page 100 - Sustainability in the Process Industry Integration and Optimization

P r o c e s s I n t e g r a t i o n f o r I m p r ov i n g E n e r g y E f f i c i e n c y 77

Once utility levels are chosen, the heat pump can be placed also
across a Utility Pinch (Figure 4.38). A special case of integration
involves the placement of refrigeration levels (Figure 4.39).
Refrigeration facilities are heat pumps whose main value is that their
cold end absorbs heat. Utilizing their hot ends for process heating
can save considerable amounts of hot utility, especially when
relatively low-temperature heating is needed.
Distillation Processes and Other Separations
The simplest distillation column includes one reboiler and one
condenser, and these components account for most of the column’s

T*
HP

MP

IP
LP

CW
ΔH
FIGURE 4.38 Heat-pump placement across the utility Pinch.

T*

R cond CW
HEAT 0
W
PUMP
R 1

R 2
ΔH

FIGURE 4.39 Refrigeration systems.