PbZn 2020: The 9th International Symposium on Lead and Zinc Processing: By-product Recovery I
Sponsored by: The Mining and Materails Processing Institute of Japan, Nonferrous Metals Society of China, GDMB: The Society for Mining, Metallurgy Resourcce and Environmental Technology, Metallurgy & Materials Society of the Canadian Institute of Mining, Metallurgy & Petroleum, TMS Extraction and Processing Division, TMS: Hydrometallurgy and Electrometallurgy Committee, TMS: Process Technology and Modeling Committee, TMS: Pyrometallurgy Committee, TMS: Recycling and Environmental Technologies Committee
Program Organizers: Andreas Siegmund, LanMetCon LLC; Shafiq Alam, University of Saskatchewan; Joseph Grogan, Gopher Resource; Ulrich Kerney, Recylex; Cheng Liu, China Enfi Engineering Corporation; Etsuro Shibata, Tohoku University
Tuesday 11:00 AM
February 25, 2020
Room: 14B
Location: San Diego Convention Ctr
Session Chair: James Dahlstrom, Gopher Resource
11:00 AM
Hydrometallurgical Recovery of Tin from Harris Dross: Ryosuke Sato1; Koichiro Hirata1; Fumito Tanaka1; 1Mitsubishi Materials Corporation
Emerged businesses in recycling have been causing the accumulation of impurities in by-processes in base-metals smelters. In lead smelters, such impurities are basically removed by drossing. Since drosses comprise several impurity elements of approximately 20mass% each as well as lead, they require further treatment to separate into each element. Conventional pyrotreatments are, however, not effective due to affinity of impurity elements at high temperatures. The authors have developed a hydrometallurgical process to recover tin and lead separately from Harris dross which is composed mainly of tin, arsenic, and lead. In the process developed, Harris dross is leached to separate lead-bearing residue, then the leachate is mixed with limestone to precipitate burtite (CaSn(OH)6) selectively, and the effluent is mixed with slaked lime to precipitate calcium arsenate. Lead-bearing residue can be recycled to the blast furnace while burtite can be payable for tin smelters because impurities in burtite are negligible.
11:20 AM
Pb & Other Impurities Recovery from Cu Smelting Residues in JX Nippon Mining & Metals: Nobuaki Okajima1; Takuma Takei1; Shojiro Usui1; 1JX Nippon Mining & Metals Corporation
The amount of impurities, such as Pb, Sn, Sb, Bi, had increased in the copper smelting process of JX Nippon Mining & Metals Group, because of its active recycling from the urban-mine. Accordingly, it became a critical issue to bleed off such impurities from its Cu smelting circuit and recover them as products. The company constructed the plant to treat the residues from Cu smelters in the Hitachi Works in 2008. The plant, named as HMC (Hitachi Metal-Recycling Complex), has been playing an important role to bleed off and recover 11 kinds of precious metals & impurity elements, and to stabilize the Cu smelting operation with recycling activities. This report describes about the role of HMC process, especially on Pb and Sb recovery.
11:40 AM
Improving the Byproduct Availability in Zinc Production: an Alternative Extraction Process for Indium: Xinkai Fu1; Katrin Daehn1; Antoine Allanore1; Elsa Olivetti1; 1Massachusetts Institute of Technology
The large-scale application for photovoltaic materials could significantly intensify the demand for indium used in copper-indium-gallium-selenide thin films. However, indium is currently being produced almost entirely as a byproduct of zinc smelting and refining, where indium is recovered in the hydrometallurgical residues of zinc purification process. Therefore, the availability of indium can be limited by zinc production. In this work, we propose an alternative indium extraction process, based on carbothermic reduction of sphalerite in the presence of calcium oxide. This process could allow indium to be separated from zinc at minesite instead of at smelters and refineries, and increase indium recovery rate and cost efficiency. With this proposed process, we estimate that up to 20% of global identified indium resources have the economic feasibility to produce indium as a primary product or co-product of zinc.
12:00 PM
Pyrometallurgical Recovery of Valuable Metals from Flue Dusts of Copper Smelter through Lead Alloy: Wenzhao Cui1; Mao Chen2; Baojun Zhao2; 1Dongying Fangyuan Nonferrous Metals Co. Ltd; 2University of Queensland
Increased low-grade copper concentrates containing impurities such as As, Pb, Zn are used in copper production. In copper smelting and converting processes, a large amount of flue dusts are collected from the waste heat boiler (WHB) and the electrostatic precipitator (ESP). The dusts consisting of Cu, Pb, Zn, As, Fe, Bi, Ag are presented in the forms of sulphate, sulphide and oxide. The complex combination of these minerals makes it difficult to recover the valuable metals from a single lead-reduction process. Different approaches have been compared through experimental studies and thermodynamic calculations to efficiently recover most of the valuable metals and obtain clean slag. It was found that leaching, oxidation and reduction are essential steps to fix arsenic and recover valuable metals. Optimum conditions for high temperature processes of oxidation and reduction have been proposed. Most of the Ag and Bi can be recovered from lead alloy.