Leak rate modeling for Iodine filter in NPP Krško PCFV system during normal operation

Tijekom posljednjih nekoliko godina velika se pažnja pridaje nuklearnoj sigurnosti. U NE Krško je u tom pogledu ugrađen PCFV sustav čiji je sastavni dio jodni filtar. U sklopu ovog rada obrađeno je modeliranje propuštanja tog filtra u normalnom pogonu. Zbog aktivnog materijala zeolita koji se nalazi u filtru potrebno je zadržati njegova aktivna filtracijska svojstva. Model filtra je napravljen u programskom paketu GOTHIC. Uz pomoć mjerenih podataka model je podešen tako da može simulirati uvjete u kojima se filtar nalazi u normalnom pogonu. Ovim modelom napravljen je proračun sniženja tlaka za filtar inicijalno napunjen na projektni nadtlak od 50 mbar.Over the past few years great attention has been paid to nuclear safety. In NPP Krško there is a PCFV system embedded in this regard, whose integral component is iodine filter. As part of this paper, the modeling of leakage of this filter in normal operation was elaborated. Because of the active zeolite material contained in the filter it is necessary to retain its active filtration properties. The filter model was created in software package GOTHIC. With the aid of measured data, model is tuned to simulate conditions in which the filter is in normal operation. The model is used to calculate pressure decrease for a filter initially filled to a project overpressure of 50mbar