Author:
Ndayiragije Jean Pierre,Su’ud Zaki,Waris Abdul
Abstract
Abstract
The Modified CANDLE (MCANDLE) burnup scheme divides the reactor core into several regions in an axial or radial direction with equal volume. It works like the CANDLE burnup scheme except that, in the CANDLE burnup scheme, the reactor core is divided into three main regions in the axial direction. Namely, spent fuel, burning region and fresh fuel region. In this study, the design of a modular modified CANDLE fast reactor using helium gas as a coolant has been performed. One of the important roles of a modified CANDLE fast reactor is that it can utilize natural uranium as fuel without the need for enrichment or reprocessing. This type of reactor can be used, including in developing countries, without the nuclear proliferation problem. Using helium gas as a coolant gives hope for a fast reactor due to its properties, such as its less neutron absorption, less radioactive, and as helium is an inert gas, prevents chemical reactions with other materials. The study was performed on a rector with a thermal power of 450MWth. The active core was divided into ten regions with equal volume in radial directions. The refueling scheme has been optimized every ten years of burnup to obtain a good reactor design. In the beginning, the fuel was put in the first region after ten years of burnup was moved to the second region, after another ten years of burnup was moved to the third region and so on until the tenth region where the fuel gets out. The neutronic calculation has been performed using the SRAC (Standard Reactor Analysis Code system). The collision probability method (PIJ) was employed for cell burnup calculation, and CITATION was used for the reactor core design with JENDL 4.0 as the nuclear data library.