Evaluation of Ferroniobium Carbide Production in a Laboratory-Scale Plasmacan Furnace

Abstract

The Plasmacan furnace is a transferred arc, falling film, plasma furnace designed for the treatment of fine particles. A 60-kW research prototype of this furnace was tested for the production of ferroniobium carbide by the carbothermic reduction of pyrochlore. Only low niobium content alloys could be made because the prototype furnace was heavily-cooled and limited in arc current. The desired conversion of 30% could be obtained in the sleeve of the furnace and high conversions were achieved in batch experiments. The results showed that conversion reaches a maximum and then decreases as the specific energy consumption (SEC) is increased because the quality of the molten falling film is optimized at intermediate SECs. The results suggest that a ferroniobium of commercial specifications except for a high carbon content could be produced in a larger scale Plasmacan furnace process.