Polonium behavior following a vacuum window rupture in a lead-bismuth eutectic based accelerator driven system

Erik Karlsson; Jörg Neuhausen; Alexander Aerts; Ivan I Danilov; Robert Eichler; Andreas Türler; Alexander Vögele

doi:10.1016/j.apradiso.2020.109551

Polonium behavior following a vacuum window rupture in a lead-bismuth eutectic based accelerator driven system

Appl Radiat Isot. 2021 Feb:168:109551. doi: 10.1016/j.apradiso.2020.109551. Epub 2020 Dec 4.

Authors

Erik Karlsson¹, Jörg Neuhausen², Alexander Aerts³, Ivan I Danilov¹, Robert Eichler¹, Andreas Türler⁴, Alexander Vögele⁵

Affiliations

¹ Paul Scherrer Institut, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland; University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.
² Paul Scherrer Institut, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland. Electronic address: joerg.neuhausen@psi.ch.
³ SCK·CEN, Boeretang 200, 2400, Mol, Belgium.
⁴ University of Bern, Freiestrasse 3, 3012, Bern, Switzerland.
⁵ Paul Scherrer Institut, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland.

PMID: 33307436
DOI: 10.1016/j.apradiso.2020.109551

Abstract

Accelerator driven fast nuclear reactors cooled by lead-bismuth eutectic (LBE) are developed for transmuting long-lived radionuclides in spent nuclear fuel. Due to the nature of the coolant, operating the reactor will result in a production of ²¹⁰Po by neutron capture. Understanding the behavior of this highly radiotoxic nuclide in the event of a failure of the window separating the evacuated proton beam guide from the reactor core is required for safety assessments. The present work aims at acquiring this knowledge by studying the evaporation of polonium from neutron-irradiated LBE and its deposition in a scaled down model of the beam tube. Experimental results along with Monte Carlo simulations indicate that polonium adsorbs as a single species with an adsorption enthalpy of approximately -156 kJ/mol.

Keywords: Accelerator driven system; Adsorption; Lead-bismuth eutectic; Polonium; Stainless steel; Thermochromatography; Transmutation; Vacuum.