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The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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2024 ANS Winter Conference and Expo
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Orlando, FL|Renaissance Orlando at SeaWorld
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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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Nuclear new build procurement considerations
It may seem counterintuitive, but the best time to enhance the ability to support operations and maintenance for a new plant is before construction starts. This is one of many lessons learned by the currently operating nuclear fleet. As construction and startup of many nuclear facilities was completed, it quickly became evident that the ability to efficiently support operations and maintenance was limited. Most of the information necessary to establish and manage procurement of spare and replacement items, maintenance, and configuration of the facilities was unavailable and had to be gathered on a case-by-case, “on-demand” basis. Absence of necessary information and the associated challenges resulted in the need for staff augmentation and multiyear-long projects to develop equipment bills of material and maintenance programs and to perform technical evaluations for the huge quantities of spare and replacement items being requested.
S. Brandes, H. Daoud, U. Schmid, V. Drüke
Nuclear Science and Engineering | Volume 97 | Number 2 | October 1987 | Pages 89-95
Technical Paper | doi.org/10.13182/NSE87-A27457
Articles are hosted by Taylor and Francis Online.
The pebble-bed prototype thorium high-temperature reactor represents the second step of high-temperature gas-cooled reactor development in the Federal Republic of Germany. Nuclear commissioning of the plant began in August 1983 with the loading of the spherical elements, and first criti-cality was achieved in September 1983 with the loading of 198 180 spherical elements. A very good agreement of 0.004Δk was achieved between measured and calculated values. After full loading of the core with 674200 elements in October 1983, core physics tests were performed in air and nitrogen in August 1984 to verify the design calculations. In these tests the temperature coefficient, the control rod worths, and the reactivity of the reactor core were measured. The measured values of the temperature coefficient were within 10% of the expected values. The agreement between measured and expected control rod worths (5%) is excellent. The reactivity of the cold core with all rods withdrawn was determined to be 0.112 ± 0.005Δp. Taking into account values of the packing density of the spherical elements, which were higher than expected, the calculated value of 0.11Δp was in very good agreement.