Überblick über die neueren Arbeiten auf dem Gebiet des Wasserstoff-und Tritiumverhaltens in Hochtemperaturreaktoren

This report comprises the contributions of members of the "Institut für Reaktor-Entwicklung" (IRE) to the "Und Seminar on Hydrogen and Tritium Behaviour in High Temperature Reactors", which was held March 8, 1978, at KFA Jülich. At the beginning the problem is introduced and the investigations at IRE related to this area are presented in their context. Then follow the individual papers on the subjects mentioned. At first the experiences with the operation of the experimental facility AUWARM and the newest results in the current testing program are discussed. Therafter the model investigations with hydrogen and deuterium on the problem of hydrogen- and tritium permeation are reported and a computer program for balancing tritium in pebble-bed-HTRs is described. Last notleast the studies on the behaviour of tritium in matrix graphite and the experiments on primary coolant purification by titanium gettering are shortly communicated. The results given in this report are preliminary informations on the actual status of the current investigations

Direkte Endlagerung ausgedienter Brennelemente DEAB Strahlenexposition im bestimmunsgemaessen Betrieb

The collective dose to the personnel from external irradiation and inhalation is below 10% of the occupational dose limit for personnel belonging to category A defined according to section 49 StrlSchV (German radiation protection ordinance). The potential radiation exposure of the population, adults and infants, is derived via the airborne exposure pathway. The results show that the derived doses are markedly below the dose limits defined in section 45 StrlSchV, despite the very conservative figures used for the emission source strength. The radiation dose to the lungs of an infant, for instance, is derived to be below 4% of the dose limit. (HP)Die Kollektivdosis des Betriebspersonals durch aeussere Strahlung und Inhalation liegt unterhalb 10% des Dosisgrenzwertes fuer beruflich exponierte Personen der Kategorie A nach Paragraph 49 StrlSchV. Die potentielle Strahlenexposition wird fuer Erwachsene und Kleinkind berechnet via Ableitung durch den Luftpfad. Die Grenzwerte des Paragraph 45 StrlSchV werden deutlich unterschritten trotz der sehr konservativ ausgesetzten Emissionsquellstaerke. Im Fall der Lunge beim Kleinkind liegt die Strahlenbelastung unter 4% des Grenzwertes. (HP)Available from TIB Hannover: RO 6452(52)+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Ein neuer Ansatz zur Bewertung der Wirksamkeit von Barrieren im Endlager. Hauptband und Kurzfassung. Technischer Anhang 1: Risikobezogene Bewertung begrenzter Freisetzungen. Technischer Anhang 2: Dokumentierte Erfahrung hinsichtlich dichter Dammbauwerke im Salinar. Technischer Anhang 3: Grundlagen der Bewertung von Hydroxylapatit als chemische Barriere gegenueber Schwermetallen Abschlussbericht

Multi-barrier systems are accepted as the basic approach for long term environmental safe isolation of radioactive waste in geological repositories. Assessing the performance of natural and engineered barriers is one of the major difficulties in producing evidence of environmental safety for any radioactive waste disposal facility, due to the enormous complexity of scenarios and uncertainties to be considered. This report outlines a new methodological approach originally developed basically for a repository in salt, but that can be transferred with minor modifications to any other host rock formation. The approach is based on the integration of following elements: (1) Implementation of a simple method and efficient criteria to assess and prove the tightness of geological and engineered barriers; (2) Using the method of Partial Safety Factors in order to assess barrier performance at certain reasonable level of confidence; (3) Integration of a diverse geochemical barrier in the near field of waste emplacement limiting systematically the radiological consequences from any radionuclide release in safety investigations and (4) Risk based approach for the assessment of radionuclide releases. Indicative calculations performed with extremely conservative assumptions allow to exclude any radiological health consequences from a HLW repository in salt to a reference person with a safety level of 99,9999% per year. (orig.)Published in 5 separate volumesSIGLEAvailable from TIB Hannover: F01B581+a: F01B582+a: F01B583+a: F01B584+a: F01B585+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman