HTGR Knowledge Base

Conference Article: Fission product behaviour in the primary circuit of an HTR

Decken, C.B. von der; Iniotakis, N. (Kernforschungsanlage Juelich G.m.b.H. (Germany, F.R.))

Abstract

The knowledge of fission product behaviour in the primary circuit of a High Temperature Reactor (HTR) is an essential requirement for the estimations of the availability of the reactor plant in normal operation, of the hazards to personnel during inspection and repair and of the potential danger to the environment from severe accidents. On the basis of the theoretical and experimental results obtained at the ''Institute for Reactor Components'' of the KFA Juelich, the transport- and deposition behaviour of the fission- and activation products in the primary circuit of the PNP-500 reference plant has been investigated thoroughly. Special work had been done to quantify the uncertainties of the investigations and to calculate or estimate the dose rate level at different components of the primary cooling circuit. The contamination and the dose rate level in the inspection gap in the reactor pressure vessel is discussed in detail. For these investigations in particular the surface structure and the composition of the material, the chemical state of the fission products in the cooling gas, the composition of the cooling gas and the influence of dust on the transport- and deposition behaviour of the fission products have been taken into account. The investigations have been limited to the nuclides Ag-110m. Cs-134 and Cs-137

view the full text of this article (7 pages, format: PDF, size= 373kB)

key words: cesium 134; cesium 137; contamination; deposition; diagrams; dose rates; fission products; htgr type reactors; kernforschungsanlage juelich; primary coolant circuits; radionuclide migration; silver 110; beta decay radioisotopes; beta-minus decay radioisotopes; cesium isotopes; cooling systems; gas cooled reactors; graphite moderated reactors; intermediate mass nuclei; internal conversion radioisoto; isomeric transition isotopes; isotopes; national organizations; nuclei; odd-even nuclei; odd-odd nuclei; radioactive materials; radioisotopes; reactor components; reactor cooling systems; reactors; silver isotopes;
Reference:
Specialists meeting on coolant chemistry, plate-out and decontamination in gas-cooled reactors Juelich, Federal Republic of Germany 2-4 December 1980
International Atomic Energy Agency, Vienna (Austria)
IWGGCR--2, pp:68-74