The radioactivity analysis of {sup 14}C in the graphite samples from the dismantled KRR-1 and 2 sites by a high temperature furnace and a LSC
- Korea Atomic Energy Research Institute (Korea, Republic of)
The radioactivity of {sup 14}C of the graphite samples from the dismantled Korea Research Reactor 1 and 2 (the KRR-1 and 2) site was analyzed and proposed to be disposed of as a low level radioactive waste rather than self-disposed of. The graphite wastes, with a weight of seven tons, have been generated during the dismantling of a research reactor with a capacity of one MW from 1995 to 2006. The graphite was used as a moderator for the research reactor and so has been radio-activated by thermal neutron. It was thought that the graphite wastes mainly included a radioisotope of stable carbon, {sup 14}C, a pure beta emitter with a half life of 5,730 years and with a maximum decay energy of 156 keV. Therefore, it has been requested to sec whether the dismantled graphite radioactive wastes including {sup 14}C can be self-disposed of or not. In the present study, the radioactivity of {sup 14}C in the graphite sample used in the research reactor was analyzed by using a commercialized high temperature furnace and a Liquid Scintillation Counter (LSC). The combustion temperature of the furnace was five hundred degrees centigrade and especially the temperature in the catalyst region was eight hundred degrees centigrade. The recovery from the furnace was 95% for {sup 14}C and the LSC had a quenching efficiency of approximately 66%. Carbosorb was used as a trapping solution for {sup 14}C. The radioactivity of {sup 14}C was measured by a LSC through the procedure of a pre-treatment such as the combustion of a sample in the temperature range of 500-800 degrees centigrade by a high temperature furnace, trapping of {sup 14}C into Carbosorb and cocktailing it with a scintillator. The radioactivity was analyzed to have a concentration with a value of much more than a domestic legal limit for a self-disposal. And an individual effective dose rate estimation was also carried out. Finally, it is suggested that the graphite wastes from the dismantled research reactor should be disposed of at a low level radioactive waste disposal site and monitored. (authors)
- Research Organization:
- American Society of Mechanical Engineers (ASME), Three Park Avenue, New York, NY 10016-5990 (United States); Technological Institute of the Royal Flemish Society of Engineers (TI-K VIV), Het Ingenieurshuis, Desguinlei 214, 2018 Antwerp (Belgium); Belgian Nuclear Society (BNS) - ASBL-VZW, c/o SCK-CEN, Avenue Hermann Debrouxlaan, 40 - B-1160 Brussels (Belgium)
- OSTI ID:
- 21156341
- Resource Relation:
- Conference: ICEM'07: 11. International Conference on Environmental Remediation and Radioactive Waste Management, Bruges (Belgium), 2-6 Sep 2007; Other Information: Country of input: France; 7 refs.; Proceedings may be ordered from ASME Order Department, 22 Law Drive, P.O. Box 2300, Fairfield, NJ 07007-2300 (United States)
- Country of Publication:
- United States
- Language:
- English
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