Modelling of the Radiological Contamination of the RBMK-1500 Reactor Control and Protection System Channels’ Cooling Circuit

Gintautas Poskas^1,2, Rimantas Zujus¹

¹Nuclear Engineering Laboratory, Lithuanian Energy Institute, Kaunas, Lithuania.
²Department of Thermal and Nuclear Energy, Kaunas University of Technology, Kaunas, Lithuania.

DOI: 10.4236/wjet.2015.33C001                

Abstract

The article presents results of modelling and analysis of component contamination of the RBMK- 1500 reactor Control and Protection System channels’ Cooling Circuit (CPSCC) at Ignalina NPP Unit 1. The modelling was performed using a computer code LLWAA-DECOM (Tractebel Energy Engineering, Belgium), taking into consideration CPSCC components characteristics, parameters of the water flowing in the circuits, system work regimes, etc. During the modelling, results on activity of CPSCC components’ deposits, nuclide composition of the deposits and dose rates after the final shutdown of the reactor, as well as activity decay of the most contaminated CPSCC components’ deposits were obtained. Analysis showed that there is a significant difference in contamination levels between CPSCC components. The rundown header from the channels of the reactor’s fast acting scram system is the most contaminated component, and contamination of the least contaminated component is only 0.27% compared to the activity of the most contaminated component. Corrosion nuclides are the nuclides that mostly contribute to contamination of the CPSCC deposits.

Keywords

Ignalina NPP, RBMK-1500 Reactor, Radiological Contamination

Conflicts of Interest

The authors declare no conflicts of interest.

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