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Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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.”
Humberto E. Garcia
Nuclear Technology | Volume 123 | Number 2 | August 1998 | Pages 166-183
Technical Paper | Decontamination/Decommissioning | doi.org/10.13182/NT98-A2890
Articles are hosted by Taylor and Francis Online.
Production of sodium hydroxide has been an important process in the chemical industry. Sodium hydroxide can be derived in several ways. One way in particular is based on combining liquid sodium with water in a caustic medium. This reaction has appeared in the nuclear industry as an important process in current decommissioning activities for liquid-metal nuclear reactors. The significance is explained as follows. Liquid-metal reactors often use liquid sodium as a heat transfer medium. Being radioactive and chemically reactive, this sodium is a mixed waste that must be processed before disposal. An accepted solution is to convert the radioactive liquid sodium to sodium carbonate, a chemically inert low-level waste suitable for near-surface burial. The conversion can be carried out in two independent processes. A first process converts sodium to sodium hydroxide. A second process converts the resulting caustic product to sodium carbonate. The former process is addressed, i.e., the chemical process of combining sodium with water in a caustic medium to produce additional sodium hydroxide. Because of the particular dynamics, characterizing this chemical process is important to predict plant behavior to control actions, disturbances, and upsetting conditions. To this end, the describing formulations of this conversion are derived in a particular physical assembly. Based on the resulting description, a computer model was developed from mass and energy balance equations, swelling predictions, and hydraulic relationships present in the system. The model was then used to synthesize a simple control strategy and to analyze its performance. In particular, the control algorithms that regulate the sodium, water, and caustic flows are discussed. The controllers were then validated by computer simulation, and some plant responses are presented.