Improvements in and relating to the electrothermal reduction of zinc ores or other oxidized zinc compounds or mixed ores, for producing metals

摘要

In a process for the reduction of oxidized zinc ores or compounds as in the parent Specification, the heat required for the endothermic reduction is provided by electricity, the charge acting as the resistance thereto, the non gaseous products being liquefied and withdrawn as the reduction proceeds, the specific voltage (volts (cm)) is decreased in a downward direction to correspond to the variations of resistivity of the charge caused by its progressive exhaustion. The variation in specific voltage may be provided by increasing the length of the current path between electrodes of a given electric circuit. The electrodes are preferably arranged in groups arranged at different levels. In the lower regions of the furnace the voltage may be substantially annulled and the heat required for completing the metallurgical reaction is generated by burning a combustible gas at the lower part of said region.