TY - JOUR
T1 - Laboratory-scale continuous bio-oxidation of a gold concentrate of high pyrite and enargite content
AU - Canales, C.
AU - Acevedo, F.
AU - Gentina, J. C.
N1 - Funding Information:
The authors acknowledge support received from FONDECYT Project 1000284 and from DI-UCV Project 203.715.
PY - 2002
Y1 - 2002
N2 - Bio-oxidation of refractory gold concentrates is currently the alternative of choice as a pretreatment stage prior to cyanidation in gold mining. Bacterial attack removes part or the entire sulphide layer that covers the gold microparticles, facilitating the gold extraction. Common sulphides found in these minerals are pyrite and arsenopyrite, while enargite is rarely found. The objective of this work was to set up a continuous bio-oxidation system for a concentrate of high enargite and pyrite content and to evaluate the effect of the hydraulic residence time (3-8 days) and the pulp density (6-24%) on the process. Results show that the bacterial attack was directed mainly to pyrite as suggested by extractions of 32% for iron (pyrite) and only 2.4% for arsenic (enargite). Increasing residence times had a positive effect on bio-oxidation, while high pulp densities had an adverse effect.
AB - Bio-oxidation of refractory gold concentrates is currently the alternative of choice as a pretreatment stage prior to cyanidation in gold mining. Bacterial attack removes part or the entire sulphide layer that covers the gold microparticles, facilitating the gold extraction. Common sulphides found in these minerals are pyrite and arsenopyrite, while enargite is rarely found. The objective of this work was to set up a continuous bio-oxidation system for a concentrate of high enargite and pyrite content and to evaluate the effect of the hydraulic residence time (3-8 days) and the pulp density (6-24%) on the process. Results show that the bacterial attack was directed mainly to pyrite as suggested by extractions of 32% for iron (pyrite) and only 2.4% for arsenic (enargite). Increasing residence times had a positive effect on bio-oxidation, while high pulp densities had an adverse effect.
KW - Metabolic stress
KW - Pulp density
KW - Refractory concentrate
KW - Stirred tank reactor
KW - Thiobacillus ferrooxidans
UR - http://www.scopus.com/inward/record.url?scp=0036193905&partnerID=8YFLogxK
U2 - 10.1016/S0032-9592(01)00303-X
DO - 10.1016/S0032-9592(01)00303-X
M3 - Article
AN - SCOPUS:0036193905
VL - 37
SP - 1051
EP - 1055
JO - Process Biochemistry
JF - Process Biochemistry
SN - 1359-5113
IS - 10
ER -