Description: Das Projekt "Measurements of fission products in the experiments mol 7C/6 and mol 7C/7" wird vom Umweltbundesamt gefördert und von Forschungszentrum Karlsruhe GmbH Technik und Umwelt durchgeführt. Objective: During core melt-down accidents, significant fractions of the fission product inventory can be released from the molten fuel to the sodium, and subsequent to vessel failure; a further release of fission products from the evaporating sodium-pool to the atmosphere will occur. The physical processes which occur in the mol 7c experiments, melting of the fuel in presence of sodium, being comparable with a real accident, interesting and important information can be obtained with respect to the source term problem of core melt-down accidents. Measurement of the activity concentration of the different fission products in the sodium and relating it to the mass of disrupted and molten fuel could provide nuclide-specific transfer factors. The unique features offered by the mol 7c experiments (release of radio nuclides from genuine molten LMFBR fuel through sodium vapour and liquid) can be fully utilized with the addition of a fission products measuring device, without interfering with the main objective of the experiment. General information: the upper part of the sodium circuit of the mol 7c in-pile section extends above the reactor top cover. So, fission product activity measurements can be made in front of the expansion tank which forms the upper part of the mol 7c loop. Activity measurements are made with a ge-li detector incorporated in an under water measuring device. This device has been conceived and used for the scanning of LWR fuel elements in the reactor pool. Between the detector and the mol 7c loop a collimator tube is installed. In front of the detector the lead shield around the upper part of the mol 7c loop is provided with a window. A preliminary evaluation of the detection limits of the fission products under theses circumstances gives the following results: - isotopes considered in the evaluation: 18 - isotopes easy to be measured: 8 sr91, i131, i133, ru103, ru105, te132, i134, i135 - isotopes detectable: 6 zr95, y92, y 93, zr97, ba140, nd149 - isotopes not detectable or with interference: 4 y91, te127m, ce144, nd147. The fabrication of the measuring device is in progress and it is scheduled to be available when the mol 7c/6 experiment is being carried out.
Types:
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Karlsruhe ? Neodym ? Barium ? Brennstoff ? Emissionsgutschrift ? Iod ? Messgerät ? Natrium ? Ruthenium ? Schneller Brutreaktor ? Strontium ? Zirkonium ? Brennelement ? Brüden ? Leichtwasserreaktor ? Sensor ? Tellur ? Blei ? Altgerät ? Main ? Isotopentechnik ? Kernreaktor ? Kernschmelze ? Kühlmittel ? Messprogramm ? Messtechnik ? Radionuklid ? Schadstoffemission ? U-Bahn ? Flüssiger Stoff ? Tankbehälter ? Messverfahren ? Reaktor ? Kerntechnischer Unfall ? Kühlung ? Messdaten ? Wasser ? Produktbewertung ? Isotop ? Nachweisgrenze ? Bohrkern ? Physikalisches Verfahren ? Gebäudefenster ? Radioaktivität ? Kernschmelzunfall ? Abschirmeinrichtung ? Stoffkreislauf ? Atmosphäre ? Forschungseinrichtung ? Anlagenbetrieb ? Physikalischer Vorgang ? Radioaktive Emission ? Kohlenstoffisotop ? Spaltprodukt ? Ytrium ? Konzentrationsmessung ? Aktivitätsmessung ?
Region: Baden-Württemberg
Bounding box: 9° .. 9° x 48.5° .. 48.5°
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 1991-03-21 - 1998-03-22
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