The chemistry of the feed water used in NPPs must be strictly controlled in both the primary and secondary systems in order to protect against corrosion, which can compromise the integrity of power plant components leading to faulty and hazardous operation. Identification of ionic contaminants in NPP water is critical for the identification and prevention of corrosive conditions and ion chromatography is an indispensable technique to identify the individual ionic species at sub- to low-μg/L concentrations.
Nuclear Energy Information
The importance of water chemistry
Nuclear power plants (NPP) generate nearly 20% of the total electricity in the U.S. and nearly 30% in the E.U. In NPPs, water in secondary and cooling systems controls the heat created from the fission of radioactive isotopes, to produce steam, which is used to generate electricity. NPP water chemistry is important for the maintenance of nuclear safety, major component reliability, and the overall economic viability of plant operation. Each nuclear power plant has a set of water chemistry matrices that are often specific for that plant and usually based on the water chemistry history and metallurgy of the plant.
In general, the typical matrices are:
- Pure water
- Pure water with amine additives
- Borated water
- Closed cooling water (with high nitrite concentrations)
- Environmental samples (effluents, soils, air, etc.)
Reagent-Free Ion Chromatography has been adopted in most NPPs due to its ease of use and improved detection limits, which make for a good fit with the typical matrices and analytes which need to be monitored in this industry.
- Download the Applications Notebook: Ion chromatography: power plant water applications summary notebook
- Download the application note: Determination of trace anions in high-purity waters by high volume/direct injection ion chromatography
- Download the application note: Determination of transition metals at PPT levels in high-purity water and SC2 (D-clean) baths
- Download the application note: Determination of trace anions in high-purity waters by IC with the Dionex IonPac As17 column using high-volume direct injection
Pure water with amine aditives
Corrosion inhibitors and oxygen scavengers are added to control pH and create a reducing environment in both liquid and vapor phases of an NPP cooling system. Morpholine and ethanolamine (ETA), the most commonly used organic amines in E.U. and U.S. NPPs, respectively, minimize corrosion by maintaining the water and vapor phase pH between 9.5 and 9.8. Ion-exchange chromatography with suppressed conductivity detection is a well established method to determine μg/L to mg/L concentrations of common cations and amines; therefore, it is the method of choice in the NPP industry.
- Download the application note: Determination of trace cations in power plant waters containing morpholine
- Download the application note: Application of eluent generation for trace anion analysis of borated waters
- Download the application note: Determination of trace nickel and zinc in borated power plant waters containing lithium hydroxide using nonsuppressed conductivity detection
- Download the application update: Determination of trace fluoride, chloride, and sulfate in lithium-containing borated waters
Closed cooling waters
In NPPs, water in secondary and cooling systems controls the heat created from the fission of radioactive isotopes, to produce steam, which is used to generate electricity. Stress-corrosion cracking and flow-assisted corrosion in the NPP boiler, secondary, and cooling systems can cause increased maintenance time and cost, and loss of power generation. Therefore, it is important to minimize corrosion in NPPs to avoid or reduce these associated events. Ion chromatography is the method of choice for the determination of potentially corrosive ionic impurities that include fluoride, chloride, and sulfate.
- Download the application note: Determination of trace anions in high-nitrate matrices by ion chromatography
- Download the application note: Fast and sensitive determination of transition metals in power industry waters using ion chromatography
- Download the application note: Determination of polyacrylic acid in nuclear power plant pressurized water reactor secondary feed water
- Download the application brief: Determination of trace anions in nuclear power plant secondary feed water containing polyacrylic acid
Ammonium and organic acids from the degradation of morpholine, ethanolamine, and hydrazine accumulate in the secondary and condenser water systems of nuclear power plants (NPPs), which require periodic flushing and blowout. This wastewater effluent, regulated by national wastewater discharge permits, limits amine discharges at levels specified for the individual NPP that range from low μg/L to low mg/L concentrations. Therefore, a sensitive method, such as ion chromatography, is needed to determine μg/L concentrations for compliance monitoring.
Access a targeted collection of scientific application notes, case studies, videos, webinars and white papers for chemical, electronic, power and energy, plastics and polymers, and paints and pigments analysis.