CINDEFI   05381
CENTRO DE INVESTIGACION Y DESARROLLO EN FERMENTACIONES INDUSTRIALES
Unidad Ejecutora - UE
artículos
Título:
Mineralogical characterization of a polymetallic concentrate Portovelo mining district. Bioleaching by a native bacterial consortium
Autor/es:
GORDILLO F.; SUAREZ J.P.; SANMARTIN V.; GENTINA J.C.; AGUIRRE P.; DONATI E.
Revista:
ADVANCED MATERIALS RESEARCH
Editorial:
Trans Tech Publications Ltd
Referencias:
Año: 2009 vol. 73 p. 481 - 484
ISSN:
1022-6680
Resumen:
The mining district of Zaruma-Portovelo of southern Ecuador is a deposit of polymetallic
sulfides worked since 1908. Currently the small traditional mining operation processes 1800 tons of
ore a day, generating environmental waste that is accumulated and systematically discharged into
the Calera and Amarillo Rivers. In this watershed area of Puyango-Tumbes, where samples were
taken and subjected to gravimetric concentration, a mineralogical analysis of the concentrate was
made. Samples of sediments taken from areas of weathered mining shafts were used to isolate
native microorganisms for subsequent molecular and physiological characterization. The mineral
concentrate contains 66.63 % of pyrite, 175 ppm Ag and 6.9 ppm Au (with 80 % of refractory
gold). This mineral was subjected to biooxidation by the isolated native organisms. In experiments
with pulp density of 10%, the solubility of the sulfides was very significant, reaching concentrations
of Fe3 + 30 g/L and sulfate 60 g/L.