The Measurement of Condensable Fission Products in the Dragon Reactor Coolant From Core 8, Charge III to Core 4, Charge V

During the operation of the Dragon Reactor from Core 8, Charge III (April 1970) to Core 4, Charge V (October 1974) the bulk coolant was sampled and analysed for condensable fission products on a routine basis using the Dracule Probe [1]. The results of these analyses together with coolant flow data has enabled the average release rates, of various Caesium, Strontium, Silver and Iodine isotopes from the core, to be calculated. The results of these calculations are tabulated in this report. The interpretation of these results and of' data from other experiments, e.g., comparison of the concentrations of condensable fission products before and after passing through a heat exchanger, is also given along with a possible explanation of the increasing Caesium and Silver release rates observed in Charge V. The approximate release rate of Caesium from FE 492 (DR-K5) was determined from data obtained during Cores 3 and 4 Charge V and is presented in the report. A brief description of the source of error in these measurements together with their effect on the core release rates is also given. (author)