PbZn 2020: The 9th International Symposium on Lead and Zinc Processing: Secondary Zinc II
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
Wednesday 2:00 PM
February 26, 2020
Room: 15A
Location: San Diego Convention Ctr
Session Chair: Etsuro Shibata, Tohoku University
2:00 PM
The EZINEX® Process for Secondary Zinc Bearing Materials: Massimo Maccagni1; Edoardo Guerrini1; 1Engitec Technologies
The problem of zinc production from secondary sources is not yet solved despite a lot of different alternatives were presented and some of them are under evaluation. The environmental pressure and the new concept of circular economy is asking for viable solutions for waste or secondary material. The EZINEX® Process is not a new technology but, industrially applied to EAF in the last decade of the last century and dormant for a long time, is newly generating some interest. Engitec started revising the old process and found and applied some modifications in order to revitalize it submitting each unit to a revision work finalized to optimize the process and to the eliminate the problems we have got in the above mentioned industrial plant experience. This new solutions were tested during an extensive work done in a demo plant. The revised process is more flexible and easy to run.
2:20 PM
Technologies for Treatment of Zinc-containing Waste from Metallurgy in KCM AD: Stefan Stoychev1; Emil Minchev1; Alexander Kyurkchiev1; Georgi Radonov1; Ivan Dobrev1; 1KCM AD
The zinc plant in KCM AD started in 1961. The current annual capacity of the plant is 75 000 tons of zinc. The technological scheme is classic – Roasting, Leaching, Electrowinning. Hydroxide cakes, generated during the leaching, are treated in the Waelz plant. In the period 2009-2011, different options for development of the company were considered with the main goals being increasing the profitability and competitiveness and minimizing the wastes for landfill. KCM decided to invest with priority in increasing the capacity of the waelz kilns and realizing a technological line for treatment of zinc-containing secondary materials and wastes, mainly EAF dusts and lead slag from the Lead plant.With the realized investments and implemented technologies, the share of treated secondary materials and wastes reached 25% of the total zinc plant input, including 10% EAFD. The circle of the recycles and residues between the two plants in KCM was closed.
2:40 PM
Zinc Reduction/ Vaporization Behavior from Metallurgical Wastes: Timothy Kerry1; Alexander Peters1; Evangelos Georgakopoulos1; Ashkan Hosseini1; Erik Offerman1; Yongxiang Yang1; 1TU Delft
The steelmaking industry produces large quantities of zinc-bearing wastes of varying forms. The amount of zinc in these materials is generally below that which is of value to the zinc smelter, consequently a method of concentration is required. Tata Steel owns and operates the pilot HIsarna ironmaking plant which, due to its high raw materials flexibility is attractive for the purpose of processing secondary iron sources. Furthermore, it can facilitate the simultaneous recovery of a zinc-enriched flue dust. The high temperature behaviour of numerous waste materials will be presented with regards to their recyclability in the HIsarna furnace. Galvanised steel scrap, blast furnace (BF) sludge and basic oxygen furnace (BOF) sludge from Tata Steel IJmuiden have been studied along with ‘goethite’ waste produced by Nyrstar. The various input materials have been comprehensively characterised and their reduction/ vaporisation behaviour recorded. Optimal process conditions for maximising zinc recovery will be elucidated.
3:00 PM
Recycling of Zinc from Galvanized Steel Scrap: Shafiq Alam1; V.I. Lakshmanan2; R. Sridhar2; 1University of Saskatchewan; 2Process Research ORTECH Inc.
A process flow sheet for zinc recovery from galvanized steel scrap in alkaline media has been studied. The process includes leaching of zinc by sodium hydroxide followed by solvent extraction using organic extractants containing oxine derivatives, such as Kelex 100, LIX-26. Zinc was stripped from the loaded organic by sulphuric acid, which was then recovered by precipitation as zinc carbonate.
3:20 PM Break
3:40 PM
Shape and Size Modification of Galvanized Steel Scrap for Introduction to the "HIsarna" Furnace: Evangelos Georgakopoulos1; Timothy Kerry1; Ashkan Hosseini1; Erik Offerman1; Yongxiang Yang1; 1TU Delft
The ReclaMet project focuses on the reclaiming of Zn, using the HIsarna iron-making process. For that, different process residues can be used as Zn sources. Steel scrap is one of these sources. However, after processing, scrap is present in different shapes and sizes. The pieces of scrap should be free flowing, and a great part of their zinc content should be readily vaporized. As a result, the optimal steel scrap shape and size must be determined.Processed steel scrap from TATA Steel, Ijmuiden, Netherlands comes in multiple different shapes and sizes. The material has been thoroughly characterized and the varying shapes have been investigated regarding i) Zn vaporization behaviour and ii) ability to flow freely in the feeding chute of the HIsarna plant. A combination of the results from these two tests has given a first indication of the optimal shape and size of steel scrap.
4:00 PM
Two Step Dust Recycling – A Modern Recycling Technology for High Zinc Containing EAF-dusts: Michael Auer1; Juergen Antrekowitsch1; 1Montanuniversität Leoben
The Waelz kiln technology is still the state-of-the-art method for the recycling of high zinc containing dusts from iron and steel industry. Due to the fact that the quality of the produced crude zinc oxide is quite low and the Waelz process is leading to again 80 % of residues which must be landfilled, the technology gets under pressure of newly developed recycling methods. One of these technologies is the 2sDR (two step Dust Recycling) process which is based on highly proved aggregates in metallurgical environment. The first step consists of a vaporization of volatile compounds under oxidizing condition in a short rotary kiln. The removal of halogens leads to a higher quality of the ZnO end-product. The second part of the new technology is operated in an electric arc furnace under reducing atmosphere and produces additionally to the ZnO an oxidic phase which should be used in construction industry.
4:20 PM Cancelled
Effect of Reducing Agent on Zinc Recovery from Primary Battery Waste in High Temperature Recycling Process: Burēak Ebin1; Martina Petranikova1; Britt-Marie Steenari1; Christian Ekberg1; 1Chalmers University of Technology
The consumption of the primary batteries, which are mainly alkaline and zinc-carbon batteries, have been rising due to increasing need to energize small portable electrical and electronic tools. The service life of primary batteries is shorter than the rechargeable batteries, and thus their usages creates high amount of waste. Battery black mass are obtained after removal of the steel shell of the spent primary batteries, and zinc is the main component of it, about 25 – 35 wt%. This research focused on to develop an environmental zinc recycling process from battery waste with reduced CO2 emission. The results show that recovery of the zinc was achieved to 99% by carbothermic reduction, and 99.8% by hydrogen reduction at 950°C. In the process, fine zinc particles were produced with a particle size varying between 200nm and 3.5µm by rapid condensation following the evaporation of zinc from the treated primary battery black mass.
4:40 PM
Production and Application of Comprehensive Recovery Process of Regenerated Zinc: Zhao Pengfei1; Dai Jianghong1; 1China ENFI Engineering Corporation
At present, secondary zinc resources are mainly concentrated in smelting dust and smelting secondary slag, including zinc dust in steel factories, zinc oxide fume in lead factories, dust in copper factories, zinc scum, furnace bottom slag and zinc smelting leaching slag. According to different characteristics of the secondary zinc resources, This paper discusses the application of zinc secondary resource recovery technology£¬and points out that the slag phase reorganization, removal of sulfur and nitrogen from flue gas£¬removal fluorine and chlorine from ashes, more metal synthesis recycling, harmless disposal of waste residue are necessary means for comprehensive utilization of secondary zinc resource. The present situation of production and application of thermal metallurgy combined with hydrometallurgy is described emphatically in this paper, so as to realize comprehensive recovery of zinc secondary resources and harmless treatment of waste residue.