Izvestiya vuzov. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

Use of Inhibitors to Prevent Oxidation in Cooling Systems of Nuclear Power Plants. Selection of the Optimal Water Chemistry Regime Using a Model Unit

3/25/2025 2025 - #01 Chemistry, physics and technology of reactor coolants

Galanin A.V. Karandeeva N.V. Vasilyeva S.Y.

DOI: https://doi.org/10.26583/npe.2025.1.07

UDC: 621.182.44

Reliable operation of nuclear power plants (NPP) critically depends on efficient and uninterrupted functioning of their cooling systems. This study examines the ongoing problems associated with formation of scale and corrosion in these systems, specifically prevention of calcium carbonate deposition in recirculating cooling systems equipped with cooling towers. These deposits are mainly formed due to an increase in the concentration of dissolved salts during evaporation of water in the process of cooling, which leads to a decrease in the heat transfer efficiency and potential equipment failures. To address these issues, the study explored a number of countermeasures, including strategic use of corrosion and scale inhibitors, as well as pH adjustment methods. The focus is on the use of stiffness stabilizers, in particular phosphonates, which are intended to transform hard and problematic CaCO3 scale into a softer and more pliable form that can be easily removed through regular maintenance procedures. Laboratory experiments were conducted to thoroughly evaluate the effectiveness of various scale formation inhibitors under simulated operating conditions reflecting the specific conditions faced by cooling towers at various nuclear power plants. The study also examined complex interaction between such factors as carbonate index and calcium transport, and their effect on the overall effectiveness of the inhibition strategies used. The analysis has resulted in a number of practical recommendations for maintaining the optimal water chemistry regime in the NPP cooling systems. The proposed strategies, which minimize the formation of deposits and ensure the best possible heat transfer efficiency, extend significantly the service life of equipment, reduce the need for expensive and destructive repairs, and ultimately improve the safety and overall efficiency of nuclear power plants. The results obtained underline the crucial role of continuous scientific research in the field of coolant chemistry, corrosion mechanisms, and the early introduction of advanced technologies to monitor and control water quality to ensure long-term operability of nuclear power plants.

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NPP-2006 water chemistry regime salt deposition inhibitors

Link for citing the article: Galanin A.V., Karandeeva N.V., Vasilyeva S.Y. Use of Inhibitors to Prevent Oxidation in Cooling Systems of Nuclear Power Plants. Selection of the Optimal Water Chemistry Regime Using a Model Unit. Izvestiya vuzov. Yadernaya Energetika. 2025, no. 1, pp. 96-112; DOI: https://doi.org/10.26583/npe.2025.1.07 (in Russian).

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