CONTRIBUCIÓN AL CONOCIMIENTO SOBRE LA MINIMIZACIÓN DEL CONSUMO DE CIANURO EN LA MINERÍA DEL ORO; SALES OXIDANTES, AIREACIÓN Y SOBREMOLIENDA PARA MINERALES CIANICIDAS

Abstract

This research aims to contribute to the knowledge about the minimization of cyanide consumption in gold mining, mainly in complex minerals such as gold sulphides and gold auroarseniides; with the use of oxidizing salts. Cyanidation assays were performed varying the cyanide concentration, aeration, pH and particle size; salts of lead acetate and lead nitrate were used as passivants. In conventional cyanidation the reagent consumptions for these minerals are high; the use of passivating salts results in a reduction in the consumption of cyanide and other reagents, under the same control parameters and mineral overmolding process. Overmolding (closed milling circuit) is the process in which the mill uses a classifier whose thick product returns to the mill, and whose fine product passes to the next separation stage. This is applied after the metallurgical characterization of the sample by microscopy, observing the partial occlusion of the gold material in pyrrhotite matrix whose treatment requires high amounts of alkali and cyanide. The treatment with lead salts (passivation salts) that superficially alter the structure of