Durability tests on plasma treated surrogate cemented concentrates and resins
- PDF / 518,023 Bytes
- 10 Pages / 432 x 648 pts Page_size
- 53 Downloads / 178 Views
MRS Advances © 2019 Materials Research Society DOI: 10.1557/adv.2019.478
Durability tests on plasma treated surrogate cemented concentrates and resins Eduardo Ferreira1*, Katrien Hendrix1, Nele Bleyen1, Elie Valcke1, Erik Coppens2, Katrien Meert2, Seif Ben Hadj Hassine² 1
SCK•CEN, Belgian Nuclear Research Centre, Boeretang 200, 2400, Mol, Belgium ONDRAF/NIRAS, The Belgian National Agency for the management of Radioactive Waste and enriched Fissile Materials, Kunstlaan 14, 1210 Brussels, Belgium
2
ABSTRACT Plasma incineration might be a promising technique for the conditioning of various radioactive waste streams. Assessing the long-term durability of the plasma slag is essential to predict its performance during long-term disposal. In this paper, the stability of six plasma treated surrogate cemented concentrates or resins in a high pH environment is investigated. The slags were crushed (2 different granulometries) and immobilized in a cement matrix, after which samples were submitted to long-term durability tests (stability under water at 20 °C; stability in a high relative humidity environment at 38 °C) and to an accelerated Alkali-SilicaReaction (ASR) test (1 M NaOH at 80 °C). The first results show that the expansion and strength loss of the cement-slag mixtures remain limited in the test conditions, although differences between the different materials and granulometries could be perceived. No visual damage was observed. Some tests are still ongoing and will last 2 years. *correspondent author: [email protected]
INTRODUCTION Plasma incineration is a thermal treatment that might be a promising technique for the conditioning of various radioactive waste streams, such as solid and liquid, organic and inorganic waste. Thermal treatments have the advantage of improving the homogeneity and the stability of the final waste form. Advantages of plasma incineration in particular are the fact that a pre-treatment of the waste is in most cases not necessary,
149
Downloaded from https://www.cambridge.org/core. UCSD University of California San Diego, on 12 Apr 2020 at 22:37:10, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1557/adv.2019.478
the final waste form is free of organic material, and the waste volume is often reduced significantly [1]. In Belgium, ONDRAF/NIRAS (the Belgian Agency for the Management of Radioactive Waste and Enriched Fissile Materials) is studying plasma incineration as an option to condition different types of radioactive waste for which the long-term stability and the compliance with the waste acceptance criteria of the near-surface disposal are to date not yet demonstrated or guaranteed. Among these waste streams are the cemented resins and concentrates from the nuclear power plant of Doel. The end product of the plasma treatment is a glassy waste form. The long-term durability of such a waste form is still unknown and very few studies can be found in the literature. Assessing its durability is essential to pred
Data Loading...
