Awards

To improve the value of recovered metals, a new operating concept for the Inco flash furnace was investigated in which the flash furnace coke addition practice aimed to establish a reducing barrier on the surface of the molten bath. The descending partially oxidized sulfide mineral particles would reach the supernatant coke layer prior to the formation of slag. The key for success depends on the effectiveness of the coke layer to produce a sulfur deficient matte while maintaining the furnace production capacity.

The mechanism and rate of carbon reduction of the phases formed in the flash flame (i.e., sulfide (matte) and oxysulfide) were investigated by means of crucible graphite reduction tests. The objective of these tests was to measure the rate of solid graphite reduction of matte, oxysulfide, slag and matte+slag mixture at different temperatures. These tests were expected to permit understanding and explain the reduction mechanism of each material by comparing the respective reaction rates, product reaction gas compositions, reduced material assays and other relevant parameters. Direct visual inspection of the test crucibles would provide additional information.