Industrial scale demonstration of cold crucible induction melter using high temperature glass containing ZnO

Cold crucible induction melter (CCIM) is being used internationally for the vitrification of radioactive liquid wastes. In CCIM, vitrification of radioactive liquid waste is accomplished by direct high frequency induction heating employing a segmented, water-cooled crucible. The cooling of the segmented crucible produces a solidified glass layer, which acts as a protection against high temperature glass corrosion. The cold crucible induction melting technology offers higher throughput, better product quality in terms of leach resistance and waste loading, less secondary waste generation and long melter life, resulting in better plant availability and easy decommissioning. Its compact design is advantageous for in-cell application. In India, both laboratory and bench scale studies were carried out to arrive at the design parameters of an industrial scale cold crucible. Based on these experimental studies, an engineering scale cold crucible induction melter was developed for technology demonstration. A plant adaptable cold crucible induction melter with liquid feeding capability was developed subsequently to evaluate the performance of CCIM. The cold crucible induction melter was operated for the last several years to establish plant adaptable operations such as melter start up, feeding, homogenization and pouring. Sodium borosilicate glass compositions were used in the past for the performance evaluation of industrial scale CCIM using simulated wastes