Analysis of Accumulation and Crystallization of Boric Acid in the Reactor Core during WWER Emergency Operation

Abstract:

The results of hand calculation of boric acid accumulation in the core in a new generation WWER-TOI reactor in case of LOCA are presented. Variants of reducing the H₃BO₃ concentration in the HA-3 system down to 1, 2, 4 and 8 g/kg are considered. The mass of boric acid deposits on the core internals depending on the value of boric acid concentration in the HA-3 system is determined. The obtained results allow concluding that the accumulation and crystallization of boric acid in the core is possible.

• Periodical: Key Engineering Materials (Volume 743)
• Pages: 389-393
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.743.389
• Online since: July 2017
• Authors: Andrei V. Morozov*, Anna V. Pityk, Sergei V. Ragulin, Aleksandra S. Soshkina
• Keywords: Accumulation, Boric Acid, Concentration, Emergency Mode, WWER

References

[1] S.G. Kalyakin, O.V. Remizov, A.V. Morozov, Yu.S. Yur'ev, Yu.V. Klimanova, Substantiation of design functions of the passive flood system HA-2 for improved NPP project with VVER reactor, Proceedings of Graduate Schools. Nuclear Power Engineering. 2 (2003).

[2] A.V. Morozov, O.V. Remizov, A.A. Tsyganok, Experimental Study of Non-equilibrium Thermal-hydraulic Processes in a Passive VVER Core Reflooding System, Proceedings of Graduate Schools. Nuclear Power Engineering. 4 (2009) 115-123.

[3] A.V. Morozov, O.V. Remizov, Experimental Substantiation of Design Functions of the VVER Auxiliary System of Passive Core Reflooding, Thermal Engineering. 5 (2012) 22-27.

[4] A.V. Morozov, O.V. Remizov, Experimental Study of VVER Steam Generator Model Operation in Condensation Mode, Thermal Engineering. 5 (2012) 16-21.

[5] S.G. Kalyakin, A.P. Sorokin, V.A. Pivovarov, R.S. Pomet'ko, Yu.F. Selivanov, A.V. Morozov, O.V. Remizov Experimental studies of the thermophysical processes in justification of the safety of the new generation of VVER. Atomic Energy. 116. No. 4 (2014).

DOI: 10.1007/s10512-014-9856-6

[6] I.I. Schmal, M.A. Ivanov, Boric acid mass transfer processes in accidental conditions. Proceedings of the 9th International Scientific and technical conference «Safety Assurance of WWER NPP», Podolsk, JSC EDO «Gidropress», (2015).

[7] P. Cohen, Water technology of power reactors, Atomizdat, Moscow, (1973).

[8] I.U. Nikolaeva, Investigational study of boron carryover forms in conditions of low and medium temperature hydrothermal process: PhD thesis, Lomonosov Moscow State University, Moscow, (2009).

[9] O.S. Alekhin, Boric acid and sodium metaborate aqueous solutions bulk properties at temperatures 323 – 575 K and pressures of 10 – 80 MPa, Extended abstract of PhD thesis, St. Petersburg, (1994).

[10] I.I. Kopytov, S.G. Kalyakin, V.M. Berkovich, A.V. Morozov, O.V. Remizov, Experimental investigation of non-condensable gases effect on Novovoronezh NPP-2 steam generator condensation power under the condition of passive safety systems operation. Proceedings of the 17th International Conference on Nuclear Engineering, ICONE17, Brussels, (2009).

DOI: 10.1115/icone17-75942

[11] A.A. Nemodruk, Z.K. Karalova, Boron analytical chemistry, Nauka, Moscow, (1964).