Hideout and hideout return: Laboratory studies and plant measurements
- Atomic Energy of Canada Ltd., Chalk River, Ontario (Canada). Chalk River Labs.
- Ontario Hydro Nuclear Technology Services, Toronto, Ontario (Canada)
- Ontario Hydro Technologies, Toronto, Ontario (Canada)
Laboratory studies on hideout in crevices and sludge piles have identified some features of the solute concentration process. The hideout process was found to depend on the heat flux, the crevice geometry, and the permeability of the medium. Hideout in deep sludge piles and concentric crevices would produce high concentrations, because escape of solutes from such locations is diffusion controlled. Because of easier escape of solutes from crevices and corrosion-product packed broach holes at broached support plates by convection processes, the concentration attained at these sites would be lower than that attained in concentric crevices or sludge piles. Hideout return studies in Ontario Hydro`s nuclear steam generators have shown such studies to be a useful tool for monitoring the cleanliness of the steam generators and the quality of chemistry control during operation. Older stations, because of designs which caused severe fouling and consequent hideout problems, released high concentrations of solutes during the return studies. Newer stations returned very low concentrations of solute, because of the measures taken to reduce fouling of the steam generators. Crevice chemistry calculations using the hideout return data suggested that near neutral solutions exist in the crevices of the Ontario Hydro steam generators. The molar ratio (Na/a) and the predicted pH in the crevices are in a region of minimum corrosion concern according to laboratory studies, indicating that factors other than pH may play important roles in the corrosion observed in steam generators.
- OSTI ID:
- 409759
- Report Number(s):
- CONF-9510292-; ISBN 1-57570-008-4; TRN: 97:000761
- Resource Relation:
- Conference: Improving the understanding and control of corrosion on the secondary side of steam generators, Airlie, VA (United States), 9-13 Oct 1995; Other Information: PBD: 1996; Related Information: Is Part Of Control of corrosion on the secondary side of steam generators. Proceedings; Staehle, R.W. [ed.] [Univ. of Minnesota, Minneapolis, MN (United States)]; Gorman, J.A. [ed.] [Dominion Engineering, McLean, VA (United States)]; McIlree, A.R. [ed.] [Electric Power Research Inst., Palo Alto, CA (United States)]; PB: 814 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Measurement of hideout return
PWR molar ratio control application guidelines: Volume 3, Hideout return evaluation guidelines. Final report