Effect of Bioleaching Microorganisms and Solid Ore Particles on Formation of Interfacial Crud in Solvent Extraction Plants

Abstract

Effect of microorganisms and nickel sulfide ore before and after bioleaching on the emulsification was investigated. The emulsion stability was evaluated by the disengagement time or the production rate of crud. The results indicate that no crud formed and the disengagement time of system was prolonged with increasing bacteria density. And a large number of bacteria dispersed at the water-oil interface and aqueous phase and rarely existed in organic phase. The influence of bacteria on the emulsion stability was attributed to the structural characteristics and the mass transfer viscosity. And the emulsion with nickel sulfide ore after bioleaching was more stable, characterized as higher production rate of crud and lower light transmittance of aqueous phase, because bacteria alter the surface properties of minerals and increase particles’ hydrophilicity.