Abstract: Disclosed is a method of measuring radioactive material of an ingot, in which an ingot having a volume produced by subjecting metal waste generated in nuclear fuel processing or production facilities to melting decontamination undergoes gamma spectroscopy using a HPGe detector to measure gamma rays of U-235 (185.72 keV, 57.2%) among uranium isotopes, followed by performing detector calibration using a certified reference material and self-absorption correction depending on the density of a medium using MCNP computer code, and which enables rapid determination of whether the ingot subjected to melting decontamination may be self-disposed of or not.

Abstract: Disclosed is a method of measuring radioactive material of an ingot, in which an ingot having a volume produced by subjecting metal waste generated in nuclear fuel processing or production facilities to melting decontamination undergoes gamma spectroscopy using a NaI detector to measure gamma rays of U-235 (185.72 keV, 57.2%) among uranium isotopes, followed by performing detector calibration using a certified reference material and self-absorption correction depending on the density of a medium using MCNP computer code, and which enables rapid determination of whether the ingot subjected to melting decontamination may be self-disposed of or not.

Abstract: A melting apparatus for melt-decontaminating radioactive metal waste includes a melting furnace, a high frequency generator, a ladle, a bogie, a cooling unit and a dust collector. In detail, the melting furnace includes a crucible into which the metal waste is input, and an induction coil which is wound around the crucible to melt the metal waste. The induction coil has a hollow hole in which cooling fluid flows. The high frequency generator applies high-frequency current to the induction coil. The ladle supplies molten metal, from which slag has been removed in the crucible, into molds. The bogie is disposed adjacent to the ladle and is provided with the molds, each of which forms an ingot using the molten metal supplied thereinto. The cooling unit cools the cooling fluid and circulates it along the induction coil. The dust collector filters out dust and purifies gas.

Abstract: Disclosed herein is a method of treating radioactive metal waste using melt decontamination, wherein radioactive metal waste, which is generated from nuclear fuel processing facilities or nuclear fuel production facilities, and which cannot be easily treated by surface decontamination because it has a complicated geometric shape, and the surface contamination of which cannot be measured, can be treated by melt decontamination. The method is advantageous in that radioactive metal waste, which cannot be treated by conventional surface decontamination, can be treated, so that radioactive metal waste can be recycled, thereby obtaining economic profits, and further in that a large storage space necessary for cutting and then storing radioactive metal waste is not required, and in that excessive manpower and cost are not required.

Abstract: Disclosed is a method of disposing of radioactive metal waste using melting decontamination, including sorting radioactive metal waste generated in nuclear fuel processing or production facilities by predetermined sorting criteria, and charging sorted metal waste into a melting furnace so as to be melted; adding a impurity remover to the melt of the melting furnace to remove generated slag; pouring the melt having no slag into a mold to form an ingot; subjecting the ingot to gamma spectroscopy using a gamma spectrometer to measure gamma rays of U-235 (185.72 keV, 57.2%) among uranium isotopes, performing detector calibration using a certified reference material and self-absorption correction depending on the density of a medium using MCNP computer code, and calculating total radioactivity of the ingot from the quantified radioactivity and mass of U-235; and efficiently and rapidly determining whether the ingot subjected to radioactivity measurement satisfies a clearance limit.

Abstract: Disclosed herein is a melting apparatus for melt-decontaminating radioactive metal waste. The melting apparatus includes a melting furnace, a high frequency generator, a ladle, a bogie, a cooling unit and a dust collector. The melting furnace includes a crucible into which the metal waste is input, and an induction coil which is wound around the crucible to melt the metal waste. The induction coil has a hollow hole in which cooling fluid flows. The high frequency generator applies high-frequency current to the induction coil. The ladle supplies molten metal, from which slag has been removed in the crucible, into molds. The bogie is disposed adjacent to the ladle and is provided with the molds, each of which forms an ingot using the molten metal supplied thereinto. The cooling unit cools the cooling fluid and circulates it along the induction coil. The dust collector filters out dust and purifies gas.

Abstract: Disclosed herein is a method of treating radioactive metal waste using melt decontamination, wherein radioactive metal waste, which is generated from nuclear fuel processing facilities or nuclear fuel production facilities, and which cannot be easily treated by surface decontamination because it has a complicated geometric shape, and the surface contamination of which cannot be measured, can be treated by melt decontamination. The method is advantageous in that radioactive metal waste, which cannot be treated by conventional surface decontamination, can be treated, so that radioactive metal waste can be recycled, thereby obtaining economic profits, and further in that a large storage space necessary for cutting and then storing radioactive metal waste is not required, and in that excessive manpower and cost are not required.

Abstract: Disclosed is a method of measuring radioactive material of an ingot, in which an ingot having a volume produced by subjecting metal waste generated in nuclear fuel processing or production facilities to melting decontamination undergoes gamma spectroscopy using a NaI detector to measure gamma rays of U-235 (185.72 keV, 57.2%) among uranium isotopes, followed by performing detector calibration using a certified reference material and self-absorption correction depending on the density of a medium using MCNP computer code, and which enables rapid determination of whether the ingot subjected to melting decontamination may be self-disposed of or not.

Abstract: Disclosed is a method of disposing of radioactive metal waste using melting decontamination, including sorting radioactive metal waste generated in nuclear fuel processing or production facilities by predetermined sorting criteria, and charging sorted metal waste into a melting furnace so as to be melted; adding a impurity remover to the melt of the melting furnace to remove generated slag; pouring the melt having no slag into a mold to form an ingot; subjecting the ingot to gamma spectroscopy using a gamma spectrometer to measure gamma rays of U-235 (185.72 keV, 57.2%) among uranium isotopes, performing detector calibration using a certified reference material and self-absorption correction depending on the density of a medium using MCNP computer code, and calculating total radioactivity of the ingot from the quantified radioactivity and mass of U-235; and efficiently and rapidly determining whether the ingot subjected to radioactivity measurement satisfies a clearance limit.