Cleaner extraction of lead from complex lead-containing wastes by reductive sulfur-fixing smelting with low SO 2 emission
Loading...
Access rights
openAccess
URL
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
This publication is imported from Aalto University research portal.
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
View publication in the Research portal (opens in new window)
View/Open full text file from the Research portal (opens in new window)
Other link related to publication (opens in new window)
Date
2019-02-01
Major/Subject
Mcode
Degree programme
Language
en
Pages
Series
Minerals, Volume 9, issue 2
Abstract
A novel and cleaner process for lead and silver recycling from multiple lead-containing wastes, e.g., lead ash, lead sludge, lead slag, and ferric sludge, by reductive sulfur-fixing smelting was proposed. In this process, coke and iron-containing wastes were employed as reductive agent and sulfur-fixing agent, respectively. A Na 2 CO 3 -Na 2 SO 4 mixture was added as flux. The feasibility of this process was detected from thermodynamic and experimental perspectives. The influence of Fe/SiO 2 and CaO/SiO 2 , composition of the molten salt, coke addition, smelting temperature, and smelting time on direct Pb recovery and sulfur-fixation efficiency were investigated. The optimal process conditions were determined as follows: W Coke = 15%W Pb wastes ,W Na2CO3 /W Na2SO4 = 0.7/0.3, Fe/SiO2 = 1.10, CaO/SiO 2 = 0.30, smelting temperature 1200 °C, and smelting time 2 h, where W represents weight. Under these optimum conditions, 92.4% Pb and 98.8% Ag were directly recovered in crude lead bullion in one step treatment, and total 98.6% sulfur was fixed. The generation and emissions of SO2 can be avoided. The main phases in ferrous matte obtained were FeS, NaFeS 2 , Fe 2 Zn 3 S 5 , and a little entrained Pb. The slag was a FeO-SiO 2 -CaO-Na 2 O quaternary melt.Description
Keywords
Lead recycling, Lead-iron-containing wastes, Molten salt, PbO-FeO-SiO -CaO-Na O phase diagram, SO -free sulfur fixing smelting, Wastes co-treatment and recycling
Other note
Citation
Li, Y, Yang, S, Lin, W, Taskinen, P, He, J, Wang, Y, Shi, J, Chen, Y, Tang, C & Jokilaakso, A 2019, ' Cleaner extraction of lead from complex lead-containing wastes by reductive sulfur-fixing smelting with low SO 2 emission ', Minerals, vol. 9, no. 2, 119 . https://doi.org/10.3390/min9020119