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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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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Latest News
Glass strategy: Hanford’s enhanced waste glass program
The mission of the Department of Energy’s Office of River Protection (ORP) is to complete the safe cleanup of waste resulting from decades of nuclear weapons development. One of the most technologically challenging responsibilities is the safe disposition of approximately 56 million gallons of radioactive waste historically stored in 177 tanks at the Hanford Site in Washington state.
ORP has a clear incentive to reduce the overall mission duration and cost. One pathway is to develop and deploy innovative technical solutions that can advance baseline flow sheets toward higher efficiency operations while reducing identified risks without compromising safety. Vitrification is the baseline process that will convert both high-level and low-level radioactive waste at Hanford into a stable glass waste form for long-term storage and disposal.
Although vitrification is a mature technology, there are key areas where technology can further reduce operational risks, advance baseline processes to maximize waste throughput, and provide the underpinning to enhance operational flexibility; all steps in reducing mission duration and cost.
Guanyi Wang, Yikuan Yan, Shanbin Shi, Zhuoran Dang, Xiaohong Yang, Mamoru Ishii
Nuclear Technology | Volume 205 | Number 1 | January-February 2019 | Pages 297-306
Technical Paper | doi.org/10.1080/00295450.2018.1493317
Articles are hosted by Taylor and Francis Online.
As one of the future directions of nuclear energy development, small modular reactor (SMR) designs meet the demands of safety, sustainability, and efficiency by eliminating circulating pumps and using natural circulation–driven flows to transfer fission energy to power. However, natural circulation–driven flows could be affected by two-phase-flow instability that may occur during accidental scenarios of pressurized water reactor (PWR)-type SMRs due to relatively small driving force. In view of the influence of two-phase-flow instability during accident transients for a PWR-type SMR, experiments are performed in a well-scaled test facility to investigate potential thermal-hydraulic flow instabilities during blowdown events. The test facility has a height of 3.44 m, and the operating pressure limit is 1.0 MPa. The scaling analyses ensure that the scaled phenomena, i.e., depressurization of the reactor pressure vessel (RPV) and emergency core cooling system valve actuation, could be accurately simulated in the test facility. Important thermal-hydraulic parameters including RPV pressure, containment pressure, local void fraction and temperature, pressure drop, and natural circulation flow rate are measured and analyzed during the blowdown events. Test results show that throughout the experiment the liquid level is always maintained above the heated core and the RPV pressure decreases. Oscillations of the natural circulation flow rate, water level, and pressure drop are observed during blowdown transients. Specific reasons for and mechanisms of the observed instability phenomena are discussed.