Electric melting furnace with partitioned melting cavity for solidifying

Abstract

An electric melting furnace for solidifying highly radioactive waste in glass has a melting cavity made of a non-conductive refractory and adapted to melt a raw material consisting of highly radioactive waste and a glass material by passing a current between horizontally opposing electrodes, and to extract the molten glass material through a plurality of outlet ports at a bottom portion of the furnace, the melting cavity being partitioned by a non-conductive partitioning refractory provided on the bottom portion of the furnace between outflow ports. Since the furnace is so structured that the melting cavity is partitioned by the non-electrically conductive refractory, all current lines connecting the pair of electrodes for melting the highly radioactive waste, which contains elements of the platinum group, detour around the partitioning refractory. According to the current line distribution produced, it is just as if the electrodes were located on the upper side of the refractory as seen from each section of the partitioned melting cavity. This makes it possible to prevent the current flowing between the electrodes from concentrating in deposits which collect at the furnace bottom and contain the platinum-group elements in high concentration. It is also possible to reduce melting cavity depth in comparison with the melt surface area and inter-electrode distance.