Increase in Zinc Recovery from a Silicate
Concentrate by Pre-neutralization
Process
Maria José Dias, Adelson Dias de Souza, Caio César Spindola de Oliveira,
Daniel Dayrell Pereira and Mateus Felipe Lourêdo Araújo
Abstract The Zinc leaching process of a silicate concentrate is very similar to the
sulfide concentrate. One of the differences is the acidity: for the sulfide process (after
pyrometallurgical route), it can go up to 60 g/L; for the silicate it is around 10 g/L.
However, in order to improve the zinc recovery from the silicate (97.63%), it was
necessary to increase the acidity to 25 g/L, without consuming extra neutralizing
reagent. To achieve that, the pre-neutralization process was tested where 6% of the
zinc silicate concentrate pulp was diverged to the end of the process, while 94% of all
the material received the extra acidity, resulting in an increased recovery of 98.47%.
However, when adding the diverged flow, the overall recovery falls to 98.27%. These
results showed that the pre-neutralization process is applicable to the silicate leaching
process and can increase the recovery up to 0.64%.
Keywords Silicate · Pre neutralization · Leaching
M. J. Dias · A. D. de Souza · C. C. S. de Oliveira (B) · D. D. Pereira · M. F. L. Araújo
Nexa Resources, BR040, km 284, Três Marias 39.205-000, MG, Brazil
e-mail: caio.oliveira@nexaresources.com
M. J. Dias
e-mail: maria.dias.md1@nexaresources.com
A. D. de Souza
e-mail: adelson.souza@nexaresources.com
D. D. Pereira
e-mail: daniel.pereira@nexaresources.com
M. F. L. Araújo
e-mail: mateus.araujo.ma1@nexaresources.com
© The Minerals, Metals & Materials Society 2020
A. Siegmund et al. (eds.), PbZn 2020: 9th International Symposium
on Lead and Zinc Processing, The Minerals, Metals & Materials Series,
https://doi.org/10.1007/978-3-030-37070-1_20
247
Concentrate by Pre-neutralization
Process
Maria José Dias, Adelson Dias de Souza, Caio César Spindola de Oliveira,
Daniel Dayrell Pereira and Mateus Felipe Lourêdo Araújo
Abstract The Zinc leaching process of a silicate concentrate is very similar to the
sulfide concentrate. One of the differences is the acidity: for the sulfide process (after
pyrometallurgical route), it can go up to 60 g/L; for the silicate it is around 10 g/L.
However, in order to improve the zinc recovery from the silicate (97.63%), it was
necessary to increase the acidity to 25 g/L, without consuming extra neutralizing
reagent. To achieve that, the pre-neutralization process was tested where 6% of the
zinc silicate concentrate pulp was diverged to the end of the process, while 94% of all
the material received the extra acidity, resulting in an increased recovery of 98.47%.
However, when adding the diverged flow, the overall recovery falls to 98.27%. These
results showed that the pre-neutralization process is applicable to the silicate leaching
process and can increase the recovery up to 0.64%.
Keywords Silicate · Pre neutralization · Leaching
M. J. Dias · A. D. de Souza · C. C. S. de Oliveira (B) · D. D. Pereira · M. F. L. Araújo
Nexa Resources, BR040, km 284, Três Marias 39.205-000, MG, Brazil
e-mail: caio.oliveira@nexaresources.com
M. J. Dias
e-mail: maria.dias.md1@nexaresources.com
A. D. de Souza
e-mail: adelson.souza@nexaresources.com
D. D. Pereira
e-mail: daniel.pereira@nexaresources.com
M. F. L. Araújo
e-mail: mateus.araujo.ma1@nexaresources.com
© The Minerals, Metals & Materials Society 2020
A. Siegmund et al. (eds.), PbZn 2020: 9th International Symposium
on Lead and Zinc Processing, The Minerals, Metals & Materials Series,
https://doi.org/10.1007/978-3-030-37070-1_20
247