Investigations on the radiolytic gas formation in cemented low and medium level waste products
Creators
- 1. Hahn-Meitner-Institut fuer Kernforschung Berlin G.m.b.H. (Germany, F.R.)
- 2. Kernforschungszentrum Karlsruhe G.m.b.H. (Germany, F.R.). Inst. fuer Nukleare Entsorgungstechnik
Description
Investigations on the gas formation during gamma irradiation have been carried out on three types of low and medium level waste products substantially arising from the reprocessing of LWR fuels. These include cementitious products containing NaNO3, neat cement stone and cemented Zircaloy-4 products. Oxygen and hydrogen were the only gases produced in the gamma radiolysis experiments. Cementitious products not containing nitrates nor simulated medium level waste salts gave only hydrogen upon gamma irradiation. The yields of hydrogen are between 3 and 8 ml H2 (STP) per kilogram of cement stone and megarad. The hydrogen yield is lesser by 50% when cement samples containing up to 17% by weight of Zircaloy-4 are irradiated; this may be attributed to the formation of zirconium hydride phases. The addition of nitrates has essentially two effects: the hydrogen yield drops to about one tenth in products containing 10% by weight of nitrates as compared to the nitrate-free samples; furthermore oxygen is produced in addition to hydrogen. (orig.)
Abstract (German)
Fuer 3 wesentliche Typen von LAW/MAW-Produkten aus der Wiederaufarbeitung von LWR-Brennstoffen wurden γ-Radiolysegasuntersuchungen durchgefuehrt. Die Experimente umfassten NaNO3-beladene Zementstein-Produkte, reinen Zementstein und Zircaloy-4-Zementstein-Produkte. Die γ-Radiolyseexperimente zeigten als Radiolysegase lediglich Sauerstoff und Wasserstoff. Zementsteinproben, die keine Nitrate bzw. MAW-Simulatsalze enthalten, produzieren nur H2 bei der γ-Bestrahlung. Die H2-Mengen liegen bei 3 bis 8 ml H2 (unter Normalbedingungen) pro 1 kg Zementstein und 1 Megarad. Bei Zementsteinproben, die bis zu 17 Gew.-% Zircaloy-4 enthielten, wurde die H2-Ausbeute um approx.50% gesenkt, was auf die Bildung von Zirkoniumhydridphasen zurueckgefuehrt wird. Der Zusatz von Nitraten bewirkt 2 wesentliche Effekte: Die Wasserstoffausbeute faellt bei 10 Gew.-% Nitratgehalt im Endprodukt auf approx.-1/10 im Vergleich zu den nitratfreien Proben, ausserdem wird neben H2 auch O2 produziert. (orig.)Additional details
Additional titles
- Original title (German)
- Untersuchungen zur Radiolysebildung zementierter LAW-MAW-Produkte
Publishing Information
- Journal Title
- Atomkernenerg. Kerntech.
- Journal Volume
- 37
- Journal Issue
- 4
- Series
- Atomkernenerg. Kerntech.
- Journal Page Range
- 245-248
- ISSN
- 0004-7198
INIS
- Country of Publication
- Germany
- Country of Input or Organization
- Germany
- INIS RN
- 12630060
- Subject category
- S12: MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; S38: RADIATION CHEMISTRY, RADIOCHEMISTRY AND NUCLEAR CHEMISTRY; S36: MATERIALS SCIENCE;
- Descriptors DEI
- AQUEOUS SOLUTIONS; CEMENTS; GAMMA RADIATION; GASES; HYDROGEN; INTERMEDIATE-LEVEL RADIOACTIVE; LOW-LEVEL RADIOACTIVE WASTES; NITRATES; OXYGEN; RADIOACTIVE WASTE DISPOSAL; RADIOLYSIS; ZIRCALOY 4; ZIRCONIUM HYDRIDES
- Descriptors DEC
- ALLOYS; BUILDING MATERIALS; CHEMICAL RADIATION EFFECTS; CHEMICAL REACTIONS; DECOMPOSITION; DISPERSIONS; ELECTROMAGNETIC RADIATION; ELEMENTS; FLUIDS; HOMOGENEOUS MIXTURES; HYDRIDES; HYDROGEN COMPOUNDS; IONIZING RADIATIONS; MANAGEMENT; MIXTURES; NITROGEN COMPOUNDS; NONMETALS; OXYGEN COMPOUNDS; RADIATION EFFECTS; RADIATIONS; RADIOACTIVE MATERIALS; RADIOACTIVE WASTES; SOLUTIONS; TIN ALLOYS; TRANSITION ELEMENT ALLOYS; TRANSITION ELEMENT COMPOUNDS; WASTE DISPOSAL; WASTE MANAGEMENT; WASTES; ZIRCALOY; ZIRCONIUM ALLOYS; ZIRCONIUM BASE ALLOYS; ZIRCONIUM COMPOUNDS