0
Research Papers

[+] Author and Article Information
V. Subramanian, J. M. Joseph, H. Subramanian, J. J. Noël

Department of Chemistry,
University of Western Ontario,

D. A. Guzonas

Chalk River, ON K0J 1J0, Canada

J. C. Wren

Department of Chemistry,
University of Western Ontario,
e-mail: jcwren@uwo.ca

Manuscript received April 9, 2015; final manuscript received July 13, 2015; published online February 29, 2016. Assoc. Editor: Thomas Schulenberg.

ASME J of Nuclear Rad Sci 2(2), 021021 (Feb 29, 2016) (6 pages) Paper No: NERS-15-1051; doi: 10.1115/1.4031199 History: Received April 09, 2015; Accepted August 05, 2015

## Abstract

Chemical kinetic models are being developed for the $γ$-radiolysis of subcritical and supercritical water (SCW) to estimate the concentrations of radiolytically produced oxidants. Many of the physical properties of water change sharply at the critical point. These properties control the chemical stability and transport behavior of the ions and radicals generated by the radiolysis of SCW. The effects of changes in the solvent properties of water on primary radiolytic processes and the subsequent aqueous reaction kinetics can be quite complicated and are not yet well understood. The approach used in this paper was to adapt an existing liquid water radiolysis model (LRM) that has already been validated for lower temperatures and a water vapor radiolysis model (VRM) validated for higher temperatures, but for lower pressures, to calculate radiolysis product speciation under conditions approaching the supercritical state. The results were then extrapolated to the supercritical regime by doing critical analysis of the input parameters. This exercise found that the vapor-like and liquid-like models make similar predictions under some conditions. This paper presents and discusses the LRM and VRM predictions for the concentrations of molecular radiolysis products, $H2$, $O2$, and $H2O2$ at two different irradiation times, 1 s and 1 hr, as a function of temperature ranging from 25°C to 400°C. The model simulation results are then compared with the concentrations of $H2$, $O2$, and $H2O2$ measured as a function of $γ$-irradiation time at 250°C. Model predictions on the effect of $H2$ addition on the radiolysis product concentrations at 400°C are presented and compared with the experimental results from the Beloyarsk Nuclear Power Plant (NPP).

<>

## References

Yetisir, M., Gaudet, M., and Rhodes, D., 2013, “Development and Integration of Canadian SCWR Concept With Counter-Flow Fuel Assembly,” Proceedings of 6th International Symposium on Supercritical Water-Cooled Reactors (ISSCWR-6), Shenzhen, Guangdong, China, Mar. 3–7, Canadian Nuclear Society (CNS), Canada, .
Guzonas, D. A., 2009, “SCWR Materials and Chemistry Status of Ongoing Research,” Proceedings of the GIF Symposium, Paris, France, Sept. 9–10, OECD Nuclear Energy Agency for the Generation IV International Forum, France, pp. 163–171.
Spinks, J. W. T., and Woods, R. J., 1990, An Introduction to Radiation Chemistry, 3rd ed., Wiley-Interscience, New York.
Yakabuskie, P. A., Joseph, J. M., and Wren, J. C., 2010, “The Effect of Interfacial Mass Transfer on Steady-State Water Radiolysis,” Radiat. Phys. Chem., 79(7), pp. 777–785. 0969-806X
Wren, J. C., and Glowa, G. A., 2000, “A Simplified Kinetic Model for the Degradation of 2-Butanone in Aerated Aqueous Solutions Under Steady State Gamma-Radiolysis,” Radiat. Phys. Chem., 58(4), pp. 341–356. 0969-806X
Guzonas, D. A., Brosseau, F., Tremaine, P., Meesungnoen, J., and Jay-Gerin, J.-P., 2012, “Water Chemistry in a Supercritical Water-Cooled Pressure Tube Reactor,” Nucl. Technol., 179(2), pp. 205–219.
Guzonas, D. A., Tremaine, P., and Jay-Gerin, J.-P., 2009, “Chemistry Control Challenges in a Supercritical Water-Cooled Reactor,” Power Plant Chem., 11(5), pp. 284–291.
Kritzer, P., 2004, “Corrosion in High-Temperature and Supercritical Water and Aqueous Solutions: A Review,” J. Supercrit. Fluids, 29(1–2), pp. 1–29.
Ohtaki, H., Radnai, T., and Yamaguchi, T., 1997, “Structure of Water Under Subcritical and Supercritical Conditions Studied by Solution X-ray Diffraction,” Chem. Soc. Rev., 26(1), pp. 41–51.
Galkin, A. A., and Lunin, V. V., 2005, “Subcritical and Supercritical Water: A Universal Medium for Chemical Reactions,” Russ. Chem. Rev., 74(1), pp. 21–35. 0036-021X
Lin, M., Katsumura, Y., Muroya, Y., He, H., Wu, G., Han, Z., Miyazaki, T., and Kudo, H., 2004, “Pulse Radiolysis Study on the Estimation of Radiolytic Yields of Water Decomposition Products in High-Temperature and Supercritical Water: Use of Methyl Viologen as a Scavenger,” J. Phys. Chem. A, 108(40), pp. 8287–8295.
Causey, P., and Stuart, C. R., 2011, “Test Plan for Pulse Radiolysis Studies of Water at High Temperature and Pressure,” Chalk River Laboratories, Chalk River, ON, Canada, .
Haygarth, K., and Bartels, D. M., 2010, “Neutron and β/γ Radiolysis of Water up to Supercritical Conditions. 2. SF6 as a Scavenger for Hydrated Electron,” J. Phys. Chem. A, 114(28), pp. 7479–7484. 1089-5639 [PubMed]
Lin, M., Katsumura, Y., He, H., Muroya, Y., Han, Z., Miyazaki, T., and Kudo, H., 2005, “Pulse Radiolysis of 4,4′-Bipyridyl Aqueous Solutions at Elevated Temperatures: Spectral Changes and Reaction Kinetics up to 400°C,” J. Phys. Chem. A, 109(12), pp. 2847–2854. 1089-5639 [PubMed]
Meesungnoen, J., Guzonas, D. A., and Jay-Gerin, J.-P., 2010, “Radiolysis of Supercritical Water at 400°C and Liquid-Like Densities Near 0.5  g/cm3—A Monte Carlo Calculation,” Can. J. Chem., 88(7), pp. 646–653. 0008-4042
Elliot, A. J., and Bartels, D. M., 2009, “The Reaction Set, Rate Constants and g-Values for the Simulation of the Radiolysis of Light Water Over the Range 20°C to 350°C Based on Information Available in 2008,” Chalk River Laboratories, Chalk River, ON, Canada, .
Arkhipov, O. P., Verkhovskaya, A. O., Kabakchi, S. A., and Ermakov, A. N., 2007, “Development and Verification of a Mathematical Model of the Radiolysis of Water Vapor,” At. Energy, 103(5), pp. 870–874.
Yurmanov, V. A., Belous, V. N., Vasina, V. N., and Yurmanov, E. V., 2010, “Chemistry and Corrosion Issues in Supercritical Water Reactors,” Proceedings of the Nuclear Plant Chemistry Conference, Quebec City, Canada, Oct. 3–8, Canadian Nuclear Society (CNS), Canada, Paper No. 11.02.
Gruzdev, N. I., Shchapov, G. A., Tipikin, S. A., and Boguslavskii, V. B., 1970, “Investigating the Water Conditions in the Second Unit at Beloyarsk Nuclear Power Station,” Therm. Eng., 17(3), pp. 20–22 [Teploenergetika 17 20–22 (1970) (in Russian)]. 0040-6015
Hochanadel, C. J., 1952, “Effect of Cobalt Gamma-Radiation on Water and Aqueous Solutions,” J. Phys. Chem., 56(5), pp. 587–594. 0022-3654
Subramanian, V., Nastaran, Y., Joseph, J. M., Guzonas, D. A., and Wren, J. C., 2015, “Supercritical Water Radiolysis Model Development: A Two Way Approach,” Phys. Chem. Chem. Phys. (submitted). 1463-9076
Wagner, W., and Kretzschmar, H. J., 2008, International Steam Tables—Properties of Water and Steam Based on the Industrial Formulation IAPWS-IF97, 2nd ed., Springer-Verlag, Berlin, Germany.
de Curieres, I., 2014, “The Evolution of Chemistry in PWR Nuclear Power Plants: Overview and Safety Perspectives,” Nuclear Plant Chemistry Conference, Sapporo, Japan, Oct. 26–31, Atomic Energy Society of Japan (AESJ), Japan.
Macdonald, D. D., 1992, “Viability of Hydrogen Water Chemistry for Protecting In-Vessel Components of Boiling Water Reactors,” Corrosion, 48(3), pp. 194–205.

## Figures

Fig. 1

Radiolysis product concentrations as a function of temperature predicted by the LRM and VRM after 1 s and 1 hr irradiation at a dose rate of 1000 kGy hr−1. The left panels show the concentrations in M (mol dm−3), whereas the right panels show the concentrations in units of g kg−1 (adopted from Subramanian et al. [21]).

Fig. 2

(a) Concentrations of H2 in the vapor phase and (b) H2O2 in liquid phase measured as a function of irradiation time at 250°C. The symbols represent the experimental data and the lines represent the predictions by the VRM (solid line), the LRM (broken lines) without interfacial mass transfer (without MT), and the LRM (dash dot) with mass transfer (with MT).

Fig. 3

O2 concentration predicted by the models at 250°C. The lines represent the predictions by the VRM (solid line), the LRM (broken lines) without interfacial mass transfer (without MT), and the LRM (dash dot) with mass transfer (with MT). In the experiments, [O2] was below the detection limit, which is indicated as a dotted line.

Fig. 4

Effect of H2 addition on suppression of radiolytic production of O2 and H2O2 predicted by the VRM (solid lines) and the LRM (broken lines). The shaded area enveloped by solid lines represents the range of values over different irradiation periods predicted by the VRM, and symbols represent plant data from Beloyarsk NPP Unit-1 (♦, direct H2 addition and 𝕧, NH3 addition) (adopted from Subramanian et al. [21]).

## Discussions

Some tools below are only available to our subscribers or users with an online account.

### Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related Proceedings Articles
Related eBook Content
Topic Collections