Advanced 3D Modeling and Simulation Techniques for Decommissioning of A-1 NPP

This paper deals with advanced 3D computer-aided technologies used for modelling and simulation for decommissioning purposes. Within the A-1 NPP decommissioning process a set of activities is needed to perform successful dismantling and decontamination of rooms and equipment. Optimal process of performance of D&D of underground storage tanks and auxiliary rooms were used on the base of simulation outputs. The mockup tests were performed before using remotely controlled manipulators. The human presence during decontamination and dismantling is case by case excluded due to the radiation safety and ALARA approach. Within Bohunice A-1 Decommissioning Project an advanced computer-aided technologies were/are developed and used. Modelling software packages EUCLID and 3Dipsos together with 3D-laser scanner SOISIC are used for creating of 3D models and also for the verification of as-built state of selected systems and facilities. Software IGRIP is used for computer simulations of all D&D tasks. The 3D modelling and simulation of selected rooms and technological equipment of the A-1 NPP are used consequently in the process of decommissioning preparation and implementation. 3D modelling for the verification and simulation of operating steps is presented in the paper and its contribution to avoiding of collisions and non-optimal interventions into the building and technological parts during performing particular works is evaluated. The application of 3D models for the verification and simulation of operating steps significantly contribute to the optimal planning of D&D procedures. Minimisation of occupation doses of realisation personnel is main reason why the 3D modelling and simulations are used. The paper also presented 3D models of rooms chosen to simulate specific operations (decontamination, handling of radioactive wastes and/or dismantling by remote controlled manipulators) without risk accident, high dose rates of personnel etc. Process of selection of optimal operating procedure for decontamination and dismantling is presented as well as achieved experiences and recommendations for further work.