Smelting Mechanism in the Reaction Shaft of a Commercial Copper Flash Furnace

Abstract

Water-quenched samples were taken from a commercial flash furnaceFlash furnaceat three levels along its reaction shaft during operation at high feed rate. The samples were subjected to a series of analysis and observation. Such processes of the feed in reaction shaft as oxidationOxidation, desulfurization, melting, slagSlagand matte formation and etc., variations of particle size along axial and radical direction of the shaft are investigated. The following smeltingSmeltingmechanism in reaction shaft named as ``Multi-particle and multi-phase fusion modelModel'' is proposed: (1) Fragmentation and collision of concentrate particles take place simultaneously in reaction shaft with particle size growing up. Collision produces large-size ``unit melt'' which falls into the reaction layer in the settler bath. (2) In the settler reaction layer below the shaft, weak bath smeltingSmeltingreactions take place among the shaft products, producing final matte and slagSlagwhich separate into two layers. (3) The processes in the shaft are all progressive along the whole height of the shaft. The predominant reaction in the shaft is oxidationOxidation, not reductionReduction.