Description

ASME STP-NU-038 – ASME Code Considerations for the Intermediate Heat Exchanger (IHX)

This report reviews the current experience on various high temperature reactor intermediate heatexchanger (IHX) concepts. There are several different IHX concepts that could be envisioned forHTR/VHTR applications in a range of temperatures from 850 to 950°C. The concepts that will beprimarily discussed herein are:

Tubular Helical Coil Heat Exchanger (THCHE)
Plate-Stamped Heat Exchanger (PSHE)
Plate-Fin Heat Exchanger (PFHE)
Plate-Machined Heat Exchanger (PMHE)

The primary coolant of the NGNP is potentially subject to radioactive contamination by the core aswell as contamination from the secondary loop fluid. Intermediate heat exchangers (IHXs) have beenproposed as a means of separating the primary circuit of the NGNP or other process heat applicationfrom the remainder of the plant in order to isolate the radioactivity and minimize radiation doses topersonnel as well as protect the primary circuit from contamination.