Non-Regenerative Heat Exchanger
Applications of heat exchangers may be classified as either regenerative or non-regenerative. The
non-regenerative application is the most frequent and involves two separate fluids. One fluid
cools or heats the other with no interconnection between the two fluids. Heat that is removed
from the hotter fluid is usually rejected to the environment or some other heat sink (Figure 11).
Figure 11 Non-Regenerative Heat Exchanger
Regenerative Heat Exchanger
A regenerative heat exchanger typically uses the fluid from a different area of the same system
for both the hot and cold fluids. An example of both regenerative and non-regenerative heat
exchangers working in conjunction is commonly found in the purification system of a reactor
facility. The primary coolant to be purified is drawn out of the primary system, passed through
a regenerative heat exchanger, non-regenerative heat exchanger, demineralizer, back through the
regenerative heat exchanger, and returned to the primary system (Figure 12).
In the regenerative heat exchanger, the water returning to the primary system is pre-heated by
the water entering the purification system. This accomplishes two objectives. The first is to
minimize the thermal stress in the primary system piping due to the cold temperature of the
purified coolant being returned to the primary system.