Application of multi-functional nanoparticle to nuclear power plant during severe accident or decontamination process using its magnetic property

Abstract

Radioactive nuclides are generally released into the containment during severe accident progression, and some of them exist in the coolant used for mitigation strategies such as IVR-ERVC and core catcher. Control and removal of them is crucial before releasing the coolant outside the containment. Also, primary system decontamination or related components decontamination are one of the biggest issues around the world. During decontamination process, removal efficiency, amount of radioactive wastes and control of them become important. On this basis, a system using nanoparticles with magnetite as a core material and porous layer surrounding it where functional groups are attached is proposed in this study to be applied in nuclear power plant. Magnetic property of the magnetite enables collection by external magnetic field, and porous layer enlarges surface area around the core. Specific functional groups attached on the surface can selectively catch radioactive ions. After certain cycle of usage, contaminated coolant that contains the nanoparticles could be purified through some facility called ‘collector’ where external magnetic fields are applied. With the collector, localization of the radioactive nuclides and minimization of the radioactive waste become possible using magnetic property of the particles, which will minimize the waste compared with conventional approaches where secondary pollution like big amount of radioactive coolant or related facilities are accompanied. Therefore, collection efficiency in the collector part becomes important to guarantee the system, and several calculations were performed to assess the parametric effects in this study.