Design and Research of Radioactive Waste Gas Treatment System for Medical Isotope Test Reactor

Abstract The radioactive activity concentration and gas composition of hydrogen-containing waste gas of medical isotope test reactor are very different from those of pressurized water reactor. The inert gas has higher radioactive activity concentration and contains a lot of nitrogen oxides. The difference of exhaust gas source term between test reactor and other reactor types and its cause and influence on design are analyzed. The reasonable emission control value is determined by reference to GB6249 and the site status. Based on the difference of the half-life of inert gas nuclides and the dynamic adsorption coefficient of activated carbon adsorption, the storage decay treatment of equal inert gas nuclides with short half-life (87Kr, 88Kr) and the retention adsorption treatment of 133Xe with relatively long half-life are adopted, giving full play to the advantages of the two processes, and greatly reducing the size and cost of equipment. The theoretical analysis and experimental demonstration of the effect of nitrogen oxides on the inert gas retention of activated carbon were carried out. The results showed that nitrogen oxides had no effect on the inert gas retention of activated carbon. Based on the analysis and demonstration of radioactive waste safety and system economy, the main equipment design and item classification are completed. At present, the design scheme has successfully passed the design review and safety analysis review.