29th Symposium on Fusion Technology (SOFT 2016)

P4.156 Investigation of some critical scenarios due to various failures of ICSI Cryogenic Distillation System

8 Sep 2016, 14:20

1h 40m

Foyer 2A (2nd floor), 3A (3rd floor) (Prague Congress Centre)

Board: 156

Poster H. Fuel Cycle and Breeding Blankets P4 Poster session

Speaker

George Ana (National Institute for Cryogenics and Isotopes Technologies - ICSI)

Description

During normal operation of a CANDU reactor, large amounts of tritiated heavy water is being produced as result of neutron absorption by the heavy water used as moderator and cooling agent. Tritium in the heavy water, being radioactive, brings a significant contribution to the personal doses and also represents an environmental hazard if a waterspill occurs. The Pilot Plant for T2 and D2 separation from Rm. Valcea (Romania) is an experimental facility built to confirm the technological data and the functional characteristics of equipments for designning and construction of an industrial facility capable to process the tritiated water from Units 1 and 2 from NPP Cernavoda. The technology employed is based on Liquid Phase Catalytic Exchange (LPCE) and Cryogenic Distillation (CD) processes and the whole system is in preoperation stage. The CD system consists of a cascade of four distillation columns placed inside a vaccum insulated coldbox and a refrigeration unit which provides the cooling capacity for the columns condensers. This paper analyzes some critical scenarios due to single failure mode or a combination of failures such as loss of cooling capacity, loss of cooling agent into the columns, and loss of electric power (loss of cooling power and vacuum system shut down), cases seen as conservatives for the system in order to investigate the behaviour during abnormal operation or accident. The study presented in the paper is concerning the Pilot Plant for T2 and D2 separation from Rm. Valcea but gives information and some references for the methodology that can be implemented for CD Sytem from NPP Cernavoda and ITER Isotope Separation System.