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Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Fusion Science and Technology
Latest News
College students help develop waste measuring device at Hanford
A partnership between Washington River Protection Solutions (WRPS) and Washington State University has resulted in the development of a device to measure radioactive and chemical tank waste at the Hanford Site. WRPS is the contractor at Hanford for the Department of Energy’s Office of Environmental Management.
Richard V Carlson, Richard Wilhelm, Kenji Okuno
Fusion Science and Technology | Volume 30 | Number 3 | December 1996 | Pages 895-899
Fuel Cycle and Tritium Technology | doi.org/10.13182/FST96-A11963051
Articles are hosted by Taylor and Francis Online.
A systematic program to study the long term generation of gas which results when tritiated water is stored on molecular sieve is ongoing at the Tritium Systems Test Assembly (TSTA). The gas that is generated, as the tritium decays, may result in safety concerns because the pressure generated in the disposal container may lead to a failure of the container.
Tritiated water is generated from processing tritiated effluent waste gases from TSTA process systems and experiments. Tritium contaminated waste gases are generated primarily from glovebox purges and process system evacuation. The various tritium compounds in the waste gas are converted to the oxide form and absorbed on molecular sieve. The tritiated water is collected on a fixed molecular sieve bed and when saturated, the water is regenerated into a 60 liter moisture (MC) filled with molecular sieve (approximately 45 kg of either type 4A or 13X molecular sieves). When the waste container is removed from the waste treatment system the container is evacuated to approximately 200 torr. The 60 liter container contains approximately 11 kg of water with amounts of tritium varying from 200 Ci to 30,000 Ci per container. The tritium content is determined by ion chamber measurement. These containers are eventually packaged and buried in retrievable shafts at the LANL waste facility located on site. Because of difficulty in the disposal of tritiated waste, TSTA currently has 20 waste containers on site that are part of this study. Periodically the gas in the waste container is sampled. The gas composition is measured with a mass spectrometer and an ion chamber. Properties measured are; pressure, gas composition (hydrogen, oxygen, nitrogen, helium-3, …) and tritium content. The waste containers have been stored at TSTA beginning in 1990. Measurements began in 1992.
Gas is generated in the container from the decay of tritium to helium-3 and from the effects of radiolysis. For every mole of tritium that decays two moles of helium-3 are generated. In addition, as the beta particle from the tritium decay loses energy it can cause the decomposition of the water absorbed on the sieve. Previous experiments predict that for every mole of tritium that decays, up to 26 moles of hydrogen and 16 moles of oxygen can result. Measurements to date indicate that significant hydrogen is generated, however it is generated at approximately one half the amount predicted from the previous experiments. Little oxygen has been found. The amount of helium-3 generated does not correlate with the expected amount from the estimated from the tritium loaded on the MC.