Center for Molecular Modeling - FWO M. Mertens FWO3F02015004101

210Po production in the European DEMO fusion reactor

sven — Thu, 22 Aug 2019 10:48:42 +0000

M.A.J. Mertens, U. Fischer, P. Pereslavtsev, R. Stieglitz, J.-M. Noterdaeme, S. Cottenier

Nuclear Fusion

59 (10), 106029

2019

Abstract

The radionuclide inventory plays a central role in the safety of nuclear installations both during operation and their decommissioning. In nuclear fusion reactors using Pb-Li tritium breeding blankets, the undesired production of radiotoxic ²¹⁰Po is still an unresolved safety issue. In this work, neutron transport calculations and inventory calculations are combined to predict the ²¹⁰Po inventory in a DEMO fusion reactor using either a Helium Cooled Lithium Lead or a Water Cooled Lithium Lead breeding blanket. In order to guarantee that the environmental ²¹⁰Po release associated with an ex-vessel leak-of-PbLi accident remains below the no-evacuation limit, the ²¹⁰Po concentration in the Pb-Li should be kept below 1500 appt. It was found that no Pb-Li purification is required to keep the ²¹⁰Po concentration in DEMO below this limit. However, in case the Pb-Li makes direct contact with water, more volatile Po-containing (oxy-)hydroxides could form. If these species increase the ²¹⁰Po release rate by more than a factor two, safety measures will be required. Therefore, ²¹⁰Po generation in DEMO does not pose a hazard in case of a regular ex-vessel leak-of-PbLi accident, unless possibly in case the Pb-Li makes contact with water.

DOI

http://dx.doi.org/10.1088/1741-4326/ab36aa

Po-Containing Molecules in Fusion and Fission Reactors

sven — Fri, 05 Jul 2019 15:04:35 +0000

M.A.J. Mertens, A. Aerts, I. Infante, J. Neuhausen, S. Cottenier

Journal of Physical Chemistry Letters

10 (11), 2879-2884

2019

Abstract

Fission and fusion reactors can only play a role in the future energy landscape if they are inherently safe by design. For some reactor concepts, a major remaining issue is the undesired production of radiotoxic 210Po. To filter out the volatile Po species, information on their molecular composition is needed. An experimental characterization is very challenging due to the large required amount of radioactive Po. An alternative quantum chemistry approach was taken to predict the temperature-dependent stability of relevant diatomic Po-containing molecules. Experimental data on lighter analogue molecules was used to establish a well-founded methodology. The relative occurrence of the Po species was estimated in the cover gas of (i) the lead–bismuth eutectic coolant in the accelerator-driven MYRRHA fission reactor and (ii) the Pb–Li eutectic tritium breeder in the DEMO fusion reactor. In both systems, Po is found to occur mainly as PbPo molecules and atomic Po.

DOI

http://dx.doi.org/10.1021/acs.jpclett.9b00824

M. Mertens

wim — Wed, 29 Mar 2017 08:43:20 +0000

Project promotor

S. Cottenier

Financierende instantie

FWO-aspirant

Project data

01/10/2015 to 30/09/2017

Mandaatmaanden

Project titel

Personeel

M. Mertens

Project ref.

FWO M. Mertens FWO3F02015004101