Effect of organics on nuclear cycles. Final report

Technical Report · Wed Jul 01 04:00:00 EDT 1992

OSTI ID:10171587

Riddle, J M ^[1]

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1. Halliburton NUS Environmental Corp., Pittsburgh, PA (United States). Chemistry Services Section

Organics entering the nuclear cycle undergo hydrolysis or radiolysis and form carboxylic acids, acetic, formic, and propionic acids being the most prominent. Sequestered sulfur, halogens, metal species, and silica may also be released. The corrosion effects of halogens and sulfate are reasonably well understood. Historically, organic acids at low levels (e.g., 10 to 50 ppb) in nuclear cycles have been viewed as a nuisance or as potentially detrimental. This study reviews literature references of the effects of organics in nuclear cycles. Sources of organics and corrosion effects on plant materials are given from various references. Acetate can neutralize caustic in PWR steam generator crevices, whereas formate and oxalate as sodium salts can decompose to sodium carbonate. Sodium carbonate in crevices hydrolyzes to carbon dioxide and sodium hydroxide, which promotes SCC and IGA of Alloy 600. Formate and oxalate can act as oxygen scavengers in the BWR cycle and mitigate IGSCC of austenitic stainless steel. No firm evidence exists that organic acids have caused corrosion in turbines, piping, or heat exchangers in nuclear cycles, although organic acids at high levels can cause specific corrosion effects as a result of low pH.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (United States); Halliburton NUS Environmental Corp., Pittsburgh, PA (United States). Chemistry Services Section
• Sponsoring Organization: Electric Power Research Inst., Palo Alto, CA (United States)
• OSTI ID: 10171587
• Report Number(s): EPRI-TR--100785; ON: UN92019631
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210200
36 MATERIALS SCIENCE
360105
ACETIC ACID
ADDITIVES
CARBOXYLIC ACIDS
CHEMICAL RADIATION EFFECTS
CORROSION AND EROSION
CORROSIVE EFFECTS
FORMIC ACID
HYDROLYSIS
ION EXCHANGE MATERIALS
ORGANIC COMPOUNDS
POWER REACTORS
NONBREEDING
LIGHT-WATER MODERATED
NONBOILING WATER COOLED
PROPIONIC ACID
PWR TYPE REACTORS
RESINS
STEAM GENERATORS
WATER CHEMISTRY