Evaluation of amine inhibitors for suitability as crevice buffering agents. Final report

Technical Report · Tue Mar 01 04:00:00 EST 1994

OSTI ID:10140703

Jayaweera, P ^[1]; Hettiarachchi, S ^[1]

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1. SRI International, Menlo Park, CA (United States)

This report describes the results of a research effort to evaluate the suitability of some selected amines and amino acids as a crevice-buffering agents in pressurized water reactor (PWR) steam generators. The amines may be useful for buffering acid crevices, and the amino acids, because they contain both acidic and basic groups, may be useful for acidic and caustic crevices. Five commercially available amines and two amino acids were studied during this research. The study involved (1) the hydrolysis of these commercially available amines and amino acids, including measurement of their kinetics of decomposition, in simulated steam generator bulk water at 290 C, and (2) determination of their thermal stability in a simulated crevice environment. The study showed that, although the high-molecular-weight amines undergo hydrothermal decomposition, they have a better buffering capacity than their low-molecular-weight counterparts at 290 C. The amines provide effective crevice buffering by increasing the pH of the crevice solution by as much as 2.84 and to 4.24 units in the experimental setup used in this program. It was concluded that polyamines provide excellent buffering of the simulated crevice environment at 290 C and morpholine remains the best low-molecular-weight amine investigated. However, detailed volatility studies of the amines were not considered in this work. Such data would be needed before in-plant testing to ensure that the amines can concentrate in steam generator crevices to the levels assumed in this study.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (United States); SRI International, Menlo Park, CA (United States)
• Sponsoring Organization: Electric Power Research Inst., Palo Alto, CA (United States)
• OSTI ID: 10140703
• Report Number(s): EPRI-TR--103721; ON: UN94009570
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210200
36 MATERIALS SCIENCE
360105
AMINES
AMINO ACIDS
CORROSION AND EROSION
CORROSION INHIBITORS
CORROSION PROTECTION
CREVICE CORROSION
EXPERIMENTAL DATA
INCONEL 600
MATERIALS TESTING
PH VALUE
POWER REACTORS
NONBREEDING
LIGHT-WATER MODERATED
NONBOILING WATER COOLED
PWR TYPE REACTORS
STEAM GENERATORS
WATER CHEMISTRY