Slag Reduction Kinetics of a Lead Slag
from a Secondary Lead Smelter
Stuart Nicol, Joseph Grogan, Boyd Davis and Trevor Lebel
Abstract In the classical pyrometallurgy route for lead smelting, the smelter produces a slag containing measurable quantities of lead. The lead in the slag is most
often discharged from the smelter, leading to the disposal of significant quantities
of lead. The slag needs to be safely stored to prevent the release of lead into the
environment. In this work, the recovery of lead, and other deleterious elements, from
a lead smelter slag has been investigated experimentally. Thermodynamic simulation was performed to determine the viability of a methane reduction process. Based
on the thermodynamic simulation and knowledge of the phases and distribution of
elements between the phases in the smelter slag, methane reduction was tested on
a bench scale. A comparison between the thermodynamic predictions and observations provides an insight into the processes occurring during reduction and the kinetic
limitations of this process.
Keywords Lead slags · Reduction · Slag cleaning
Introduction
In both primary and secondary lead smelters, significant quantities of lead are discharged into the environment each year. Without the use of a settling (or zinc fuming)
furnace, slag is discharged from the smelter containing between 0.5 and 3 wt% Pb [1].
This results in a smelter discharging significant quantities of lead into the surrounds
each year.
Primary smelter slag is cleaned at some smelters with the zinc fuming furnace,
resulting in a discharge slag with less than 0.1 wt% Pb. Other techniques have been
used, including settling furnaces and TSL furnaces. However, this slag cleaning is
only performed if there is sufficient zinc in the slag to make the process financially
S. Nicol · J. Grogan (B)
Gopher Resource, 685 Yankee Doodle Road, Eagan, MN 55121, USA
e-mail: joe.grogan@gopherresource.com
B. Davis · T. Lebel
Kingston Process Metallurgy, 759 Progress Avenue, Kingston, ON K7M 6N6, Canada
© 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_4
41
from a Secondary Lead Smelter
Stuart Nicol, Joseph Grogan, Boyd Davis and Trevor Lebel
Abstract In the classical pyrometallurgy route for lead smelting, the smelter produces a slag containing measurable quantities of lead. The lead in the slag is most
often discharged from the smelter, leading to the disposal of significant quantities
of lead. The slag needs to be safely stored to prevent the release of lead into the
environment. In this work, the recovery of lead, and other deleterious elements, from
a lead smelter slag has been investigated experimentally. Thermodynamic simulation was performed to determine the viability of a methane reduction process. Based
on the thermodynamic simulation and knowledge of the phases and distribution of
elements between the phases in the smelter slag, methane reduction was tested on
a bench scale. A comparison between the thermodynamic predictions and observations provides an insight into the processes occurring during reduction and the kinetic
limitations of this process.
Keywords Lead slags · Reduction · Slag cleaning
Introduction
In both primary and secondary lead smelters, significant quantities of lead are discharged into the environment each year. Without the use of a settling (or zinc fuming)
furnace, slag is discharged from the smelter containing between 0.5 and 3 wt% Pb [1].
This results in a smelter discharging significant quantities of lead into the surrounds
each year.
Primary smelter slag is cleaned at some smelters with the zinc fuming furnace,
resulting in a discharge slag with less than 0.1 wt% Pb. Other techniques have been
used, including settling furnaces and TSL furnaces. However, this slag cleaning is
only performed if there is sufficient zinc in the slag to make the process financially
S. Nicol · J. Grogan (B)
Gopher Resource, 685 Yankee Doodle Road, Eagan, MN 55121, USA
e-mail: joe.grogan@gopherresource.com
B. Davis · T. Lebel
Kingston Process Metallurgy, 759 Progress Avenue, Kingston, ON K7M 6N6, Canada
© 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_4
41