Zinc Plant Expansion and Modification
for Increased Metals Recovery
Björn Saxén, Florentino Estrada, Maciej Wrobel and Marko Lahtinen
Abstract Met-Mex Peñoles recently increased its zinc production capacity by
120,000 ton per annum at Torreón plant in Mexico. The expansion was based on
Outotec atmospheric Direct concentrate Leaching (DL) technology integrated to the
calcine leaching circuit. Also, new solution purification and electrowinning sections
were added for the increased capacity. As a continuation to the expansion, there is an
ongoing project aiming at improving recovery of silver and lead by new flowsheet
modifications and technology from Outotec. The pure jarosite process minimizing
metal losses to iron residue will be introduced in the leaching circuit. Sulfur cake
from iron reduction step of pure jarosite process will be recycled to the fluidized
bed roasting through a new feed pre-treatment system (FPS). Expected additional
benefits of FPS are reduced dust entrainment and more homogeneous temperature
distribution in roaster. This paper presents results and observations from the DL
expansion and describes the new flowsheet.
Keywords Zinc · Concentrate leaching · Roasting · Plant expansion · Silver ·
Jarosite
B. Saxén (B)
Outotec (Finland) Oy, PO Box 69 28101 Pori, Finland
e-mail: bjorn.saxen@outotec.com
F. Estrada
Metalúrgica Met-Mex Peñoles S.A. De C.V., Blvd. Laguna Poniente 3200, Col. Metalúrgica,
Torreón Coah, Mexico
e-mail: florentino_estrada@penoles.com.mx
M. Wrobel
Outotec GmbH & Co. KG, Ludwig-Erhard-Strasse 21, D-61440 Oberursel, Germany
e-mail: maciej.wrobel@outotec.com
M. Lahtinen
Outotec (Finland) Oy, PO Box 1000 02231 Espoo, Finland
e-mail: marko.lahtinen@outotec.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_32
365
for Increased Metals Recovery
Björn Saxén, Florentino Estrada, Maciej Wrobel and Marko Lahtinen
Abstract Met-Mex Peñoles recently increased its zinc production capacity by
120,000 ton per annum at Torreón plant in Mexico. The expansion was based on
Outotec atmospheric Direct concentrate Leaching (DL) technology integrated to the
calcine leaching circuit. Also, new solution purification and electrowinning sections
were added for the increased capacity. As a continuation to the expansion, there is an
ongoing project aiming at improving recovery of silver and lead by new flowsheet
modifications and technology from Outotec. The pure jarosite process minimizing
metal losses to iron residue will be introduced in the leaching circuit. Sulfur cake
from iron reduction step of pure jarosite process will be recycled to the fluidized
bed roasting through a new feed pre-treatment system (FPS). Expected additional
benefits of FPS are reduced dust entrainment and more homogeneous temperature
distribution in roaster. This paper presents results and observations from the DL
expansion and describes the new flowsheet.
Keywords Zinc · Concentrate leaching · Roasting · Plant expansion · Silver ·
Jarosite
B. Saxén (B)
Outotec (Finland) Oy, PO Box 69 28101 Pori, Finland
e-mail: bjorn.saxen@outotec.com
F. Estrada
Metalúrgica Met-Mex Peñoles S.A. De C.V., Blvd. Laguna Poniente 3200, Col. Metalúrgica,
Torreón Coah, Mexico
e-mail: florentino_estrada@penoles.com.mx
M. Wrobel
Outotec GmbH & Co. KG, Ludwig-Erhard-Strasse 21, D-61440 Oberursel, Germany
e-mail: maciej.wrobel@outotec.com
M. Lahtinen
Outotec (Finland) Oy, PO Box 1000 02231 Espoo, Finland
e-mail: marko.lahtinen@outotec.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_32
365