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Division Spotlight
Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
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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Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
Joanna McFarlane, Jungsook C. Wren, Robert J. Lemire
Nuclear Technology | Volume 138 | Number 2 | May 2002 | Pages 162-178
Technical Paper | Reactor Safety | doi.org/10.13182/NT138-162
Articles are hosted by Taylor and Francis Online.
Iodine species released into a reactor containment building following a loss-of-coolant accident is determined by the relative timing and quantity of iodine and other fission products released from the fuel, chemical thermodynamics in the fuel channel, and reaction kinetics in cooler regions of the heat transport system (HTS). Iodine speciation along the transport path from the fuel to cooler regions of the HTS and into containment is evaluated using chemical thermodynamics calculations, leading to a prediction of the volatile iodine mole fraction that theoretically would enter containment. Sensitivities to a decrease in the cesium-to-iodine ratio, a decrease in iodine concentration in the coolant, and an increase in oxygen partial pressure are tested. The role of the presence of other elements, namely, molybdenum, tellurium, uranium, and lithium, are also evaluated. Under most conditions, the mole fraction of iodine entering containment in volatile form is found to be <0.1%. There are circumstances, however, when cesium iodide can be destabilized by a low cesium-to-molybdenum ratio in an oxidizing atmosphere such as steam. To further explore this situation and to validate the code, chemical equilibrium calculations are also compared to earlier Knudsen-cell experimental studies of the interaction of cesium, iodine, molybdenum, and urania. In these experiments, the partial pressures of cesium molybdate and elemental iodine are measured as a function of temperature over the range 1100 to 1500 K. The calculated Cs2MoO4 vapor pressures agree with the experimental results within an order of magnitude at temperatures up to 1200 K; and between 770 and 1150 K, the agreement is within a factor of 2 to 5 depending on the chemical system.