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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
S. B. Kim, S. L. Chouhan, P. A. Davis
Fusion Science and Technology | Volume 60 | Number 3 | October 2011 | Pages 960-963
Measurement, Monitoring, and Accountancy | Proceedings of the Ninth International Conference on Tritium Science and Technology | doi.org/10.13182/FST11-A12575
Articles are hosted by Taylor and Francis Online.
The high mobility of tritium as HTO implies that, under steady-state conditions, the T/H ratio (or equivalently the HTO concentration) is the same in all water compartments of the environment. This is the basis of the specific activity (SA) model, which underlies almost all environmental tritium models. SA concepts apply to organically bound tritium (OBT) as well, since the OBT formed by a given plant process at a given time has a T/H ratio that reflects the ratio in the water that enters into that process. There is no empirical evidence that the bioaccumulation of tritium in aquatic and wetland plants will occur. OBT/HTO ratios less than one is consistently found in the laboratory where the HTO concentrations to which the plants are exposed can be held constant. These data suggest a value of 0.7 for the OBT/HTO ratio under equilibrium conditions in the laboratory. Theoretical considerations suggest that the value of the OBT/HTO ratio in plants is significantly different from one and, in most cases, greater than one. This is primarily due to the much longer residence time of OBT in plants as compared to HTO. The observed HTO concentrations are much higher than OBT concentrations, which makes OBT/HTO ratio smaller than unit in contrast with SA based expectations. In addition to this, the IMPACT model overpredicted HTO and OBT concentrations in plants and animals by a factor of 3 or 4, on average. This work is summary of the AECL funded research project (1).