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Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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.
Syed Hameed Qaiser, Masood Iqbal, Aamer Iqbal Bhatti, Raza Samar, Javed Qadir
Nuclear Science and Engineering | Volume 172 | Number 3 | November 2012 | Pages 327-336
Technical Paper | doi.org/10.13182/NSE11-46
Articles are hosted by Taylor and Francis Online.
This paper discusses a higher-order sliding-mode-observer design for estimating reactivity in a nuclear research reactor. The nonlinear model of the Pakistan Research Reactor-1 (PARR-1) has been tuned and validated with experimental data. This model is then used for higher-order sliding-mode-observer-based reactivity estimation. In thermal reactors, reactivity is a very important reactor variable, as it determines the change of output power variation and is the main variable being manipulated for reactor power control. Linear observers have been used in the past to estimate reactivity, but the bandwidth is limited, and performance gets degraded as the operating point is changed. A nonlinear observer can efficiently address this problem. In this paper a robust higher-order sliding-mode observer is employed to estimate this variable. The higher-order sliding-mode observer is efficient and has the main advantage of reduced chattering. The estimators predict this variable with the measurement of neutron flux only. The estimated value is in close agreement with the theoretically calculated value.