Comparison of BANDI-60 core designs using Pyrex burnable absorber and annular fuel embedding gadolinia wire

Abstract

The BANDI-60 Soluble Boron-Free Small Modular Reactor (SMR) developed by KEPCO E&C is a Pressurized Water Reactor producing 200 MW of thermal power. This study proposes core designs for the BANDI-60 using two types of burnable absorbers (BAs) and compares their characteristics. One core uses the discrete Pyrex BA, and the other uses a new BA design named “cylindrically inserted and mechanically separated burnable absorber” (CIMBA). Pyrex is the borosilicate glass consisting of B2O3-SiO2, which suppresses excess reactivity to achieve a long cycle length. CIMBA is a wire-type gadolinia (Gd2O3) BA inserted into annular fuel pellets, which utilizes a spatial self-shielding effect on the fuel material and has a greater fuel inventory than discrete BAs. The core designs are performed using a McCARD code, and the results showed both cores can operate over an approximate cycle length of 4.9 years and possess a reactivity control capability ensuring a safe shutdown.