Investivgation of on-line chelant addition to PWR steam generators. Annual report, program start through 1980. [Chemistry; compatibility]

Technical Report · Mon Nov 01 04:00:00 EST 1982

DOI:https://doi.org/10.2172/6671450· OSTI ID:6671450

Tvedt, T. J.; Wallace, S. L.; Griffin, F. Jr.

The investigation of chelating agents for continuous water treatment of secondary loops of PWR steam generators were conducted in two general areas. These were the study of the chemistry of chelating agents and the study of materials compatability with chelating agents. Both studies were conducted at conditions of temperature, pressure, and chemical environment similar to those encountered in operating steam generators. The kinetics for the thermal decomposition of the calcium complex of EDTA 230-270 C were investigated. The reaction was shown to be first order and the decomposition rate was shown to significantly increase with temperature. Initial decomposition was found to be due to hydrolysis. Iminodiacetic acid (IDA) and 2-hydroxyethyliminodiacetic acid (HEIDA) were identified as initial decomposition products. Hydrazine was shown to accelerate the decomposition reaction. The corrosivity of an EDTA/hydrazine solution on alloys which are used in PWR steam generators were studied. It was determined that the rate of corrosion decreased with time, until a condition of negligible corrosion was established. As corrosion decreased all metal surfaces became black in appearance.

• Research Organization: Dow Chemical U.S.A., Freeport, TX. Texas Div.
• DOE Contract Number: AC02-79ET34015
• OSTI ID: 6671450
• Report Number(s): DOE/ET/34015-2; ON: DE83003936
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
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36 MATERIALS SCIENCE
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ALKALINE EARTH METAL COMPLEXES
ALLOYS
AMINO ACIDS
BOILERS
CALCIUM COMPLEXES
CARBOXYLIC ACIDS
CHELATING AGENTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
CHEMISTRY
CHROMIUM ALLOYS
COMPATIBILITY
COMPLEXES
CORROSION
DECOMPOSITION
EDTA
HYDRAZINE
INCONEL 600
INCONEL ALLOYS
IRON ALLOYS
IRON BASE ALLOYS
KINETICS
NICKEL ALLOYS
NICKEL BASE ALLOYS
NIOBIUM ALLOYS
NITROGEN COMPOUNDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PWR TYPE REACTORS
PYROLYSIS
REACTION KINETICS
REACTORS
STEAM GENERATORS
STEELS
THERMOCHEMICAL PROCESSES
VAPOR GENERATORS
WATER CHEMISTRY
WATER COOLED REACTORS
WATER MODERATED REACTORS
WATER TREATMENT
YIELDS