36th Annual CNS Conference - 2016 June 19-22

Presented at:
36th Annual CNS Conference
2016 June 19-22
Toronto, Canada
Session Title:
Session W2A: Plant Life Extension 2

S. Fernandes (Amec Foster Wheeler)
M. Singh (Amec Foster Wheeler)


Nuclear power plants often require prolonged maintenance or refurbishment outages in order to replace or refurbish various critical components. In order to isolate key piping systems in a dry state, various draining and drying techniques can be applied (e.g. dry air purge, drying by heating). Vacuum drying is a technique that reduces the temperature at which evaporation can occur by lowering the air pressure within the piping. The drying of either light or heavy water results in a significant reduction of radioactive dose, emissions and associated hazards during maintenance. However, specialized equipment (vacuum pumps, heat exchangers, heaters, etc.) are required in order to successfully implement vacuum drying in the primary heat transport or moderator systems in a CANDU plant. This paper explores vacuum drying strategies and equipment considerations across previous nuclear refurbishment outages and outlines some recommendations for future outages (primarily the Ontario Power Generation’s Darlington Unit 2 Refurbishment).

Individual Conference-Paper Copies (Electronic Where Available):

  • For CNS members, the first 5 copies per calendar year are free, and additional copies are $10 each.
  • For non-members, the price is $25 for the first Conference-paper copy in a request, and $10 each for additional copies of papers in the same conference and in the same request.
  • Contact the CNS office to order reprints.