Stefan Steinlechner

• Professor
• Montanuniversität Leoben

In different nonferrous metal-producing industry sectors, the impurity element iron has to be removed from the process solution. Examples for the arising residues are jarosite or goethite precipitates from nickel or zinc production but also red mud from aluminum production. Regardless of environmental concerns, the material is landfilled in almost...

Jarosite is an iron precipitation which is generated from the zinc and nickel industries as an industrial waste. To move towards environmental protection, the recycling of such waste is crucial. Furthermore, jarosite contains valuable elements such as silver, zinc, indium, and nickel which can be extracted for economic benefits. In this context, th...

In the basic oxygen furnace (BOF) steelmaking process, large quantities of slag are generated, which are sometimes used as by-products. However, in many cases, BOF slagBOF slag is landfilled and thus seen as waste. Typically contained elements are chromium, manganese, and phosphorus aside from the main slag formers, such as oxides of iron, calcium,...

In different nonferrous metal producing industry sectors, the impurity element iron has to be removed from the process solution. Examples are the jarositeJarositeor goethiteGoethite from nickelNickelor zincZinc production but also the red mud from aluminum production. Regardless of environmental concerns, the material is land filled in almost any c...

Due to the aggravating situations regarding climate change, resource supply, and land consumption by the landfilling of residual materials, it is necessary to develop recycling processes that allow the recovery of valuable metals from industrial residues with significantly reduced CO2 emissions. In this context, it is conceivable that processes usi...

When recycling materials containing zinc in hydrochloric acid processes, the precipitation of zinc can lead to the formation of various compounds which can be assigned to the group of zinc hydroxide chlorides. This paper compares different approaches for the selective removal of chlorineChlorine extractionfrom tetra basic zinc chlorideTetra basic z...

Millions of tons of iron precipitation residues, predominantly jarositeJarosite, are accumulating in the primary zincZinc or primary precious metals industry every year. Regardless of environmental concerns the material is land filled in almost any case, although valuables such as indiumIndium, silverSilver, gold, nickelNickel, or zincZinc are pres...

The in‐plant recycling routes of several side streams produced in Electric Arc Furnace (EAF) steelmaking remain under‐explored. In article 2100472, Abdelrahim and co‐workers characterize eight side streams and use them to produce seven different briquettes. Briquettes are assessed for their suitability to be used in EAF through a series of mechanic...

The in-plant recycling routes of several side streams produced in Electric Arc Furnace (EAF) steelmaking remain under-explored. Briquetting is an attractive technique to enable recycling of in-plant side streams. Briquettes introduced into EAF must possess certain mechanical and chemical properties. However, no standard is available to determine th...

In the course of developing an innovative process for CO2-optimised valuable metal recovery from precipitation residues accumulating in the zinc industry or nickel industry, the chlorination reactions were investigated. As the basis of small-scale pyrometallurgical experiments, the selected reaction systems were evaluated by means of thermodynamic...

Comprehensive amounts of valuable elements are lost due to the disposal of waste materials which are generated during the hydrometallurgical production of zinc. Those wastes, mainly jarosite or goethite, are predominantly immobilized and disposed on open landfills whereby the contained elements are not extracted. Several strategies were investigate...

Featured Application: The aim of this investigation is a simple and easily adaptable agglomeration process for the different quantities and qualities of EAF by-products. The costs and need of disposal for these by-products will be omitted if internal, on-site recycling is possible. Abstract: In addition to the blast furnace converter route, electri...

The present paper investigates a reduction process using a carbon-saturated iron melt to treat an imerpial smelting furnace (ISF) slag. The process allows for the removal of heavy metals that are known to negatively impact the surrounding environment (Zn, Pb and As). The work includes a short characterization of the slag, describes the reductive me...

The use of secondary raw materials in metallurgical processes such as steelmaking is an important contribution to the circular economy aspired to by EU members and many other countries. The agglomeration of dusts, fines and sludges is an important pretreatment step to enable the use of these materials in subsequent melting processes, such as steelm...

In 2018, the stainless-steel industry produced > 10 million tons of slag, which for the most part was landfilled because of chromium oxide contamination. Long-term studies indicate a possible formation of soluble hexavalent chromium, which is classified as carcinogenic. Recent research focuses on the development of a treatment technology to recover...

Recent years have seen a worldwide change in the environmental policy towards circular economy approaches. It is estimated that steel-making activities in Europe produce about 80 million tonnes annually of by-products and waste, equivalent to half of the Europe-an steel production, of which more than 10 million tonnes is waste for disposal. This wa...

Based on technological reasons or in case of indium, which has gained its importance only in recent decades, metals such as zinc, indium and silver can be found in the residues or by-products of the corresponding industry like the iron precipitate—jarosite—from primary zinc production. As a result of low zinc and lead contents, targeted economic re...

Ores nowadays often show a higher complexity, containing different valuable metals as well as disturbing elements. In the state-of-the-art smelters, the majority of these elements end up as by-products. Treatment of such by-products is in many cases not done and if processes exist, they often recover only one metal, leaving a lot of value in newly...

Recent years have seen a worldwide change in the environmental policy towards circular economy approaches. It is estimated that steel-making activities in Europe produce about 80 million tonnes annually of by-products and waste, equivalent to half of the European steel production, of which more than 10 million tonnes is waste for disposal. This was...

Indium and silver are technologically important, critical metals, and in the majority of cases, they are extracted as a by-product of another carrier metal. The importance of indium has seen recent growth, and for technological reasons, these metals can be found in industrial residues from primary zinc production, such as the iron precipitate—jaros...

The aim of this work was to develop a process for the removal of Sn, Sb and As from anode slime out of copper refinery to disburden a subsequent pyrometallurgical processing for precious metals refinement. For this reason, a detailed literature survey was conducted, followed by a characterization to find the present compounds/alloys and their morph...

Industrial wastes such as slags, dust, or precipitation residues contain significant amounts of valuable metals like zinc, lead, and copper as well as precious metals like silver and indium. Nevertheless, a lot of these waste materials are not recycled, and therefore, many valuable metals end up being sent to landfills. Because of harmful component...

High amounts of Steel Mill Dust is produced worldwide each year. Although the Waelz kiln is the preferred route for processing these wastes, significant amounts of this residue stays untreated. Very often, the unprocessed dust gets landfilled and therefore, it is lost for the recovery of zinc and further heavy metals accompanied in the waste. An al...

The focus of recycling processes for industrial residues from lead, zinc and copper industry in the past was mainly on the recovery of the base metals. Silver, gold or also PGMs are well-known valuable side elements in the corresponding ores and with this significant contents can be found in some of the residues but were not recovered in the past....

The focus of recycling processes for industrial residues from lead, zinc and copper industry in the past was mainly on the recovery of the base metals. Silver, gold or also PGMs are well-known valuable side elements in the corresponding ores and with this significant contents can be found in some of the residues but were not recovered in the past....

High amounts of Steel Mill Dust is produced worldwide each year. Although the Waelz kiln is the preferred route for processing these wastes, significant amounts of this residue stays untreated. Very often, the unprocessed dust gets landfilled and therefore, it is lost for the recovery of zinc and further heavy metals accompanied in the waste. An al...

Resources and energy have an essential importance for the industrial development in Europe. Especially the relevance of recycling processes will increase, which means that the life cycle of a product has to be considered. Therefore an intensive interaction of raw material technology, metallurgy, and material science will be necessary in the future....

The metals from the platinum group are used in many different industries, for example dental, jewelry, and chemicals. Nevertheless, the most important use is based on their catalytic properties. Approximately 50% of platinum and palladium are used as automotive and industrial catalysts. In case of rhodium, an even higher percentage (around 80–90%)...

Annual global production of zinc is more than 13 million tons. More than 50% of this amount is used for galvanizing while the rest is mainly split into brass production, zinc-based alloys, semi manufacturers and zinc compounds such as zinc oxide and zinc sulfate. For the zinc and steel industries, recycling of zinc-coated steel provides an importan...

Environmental legislation, limited resources as well as high metal prices force the metallurgical industry more and more to make use of secondary materials. For this, also residues from metal production are nowadays considered as a possible resource. Due to their often complex structure and the presence of a multi-metal-system, efficient recycling...

The product quality in the zinc oxide market significantly influences the possible utilization area. Therefore, in this paper, reactions between halide and matrix were determined depending on the impurity compound, treatment temperature and retention time. It is shown that during a thermal purification step, halides like NaCl, NaF, KF or KC1 have a...

Today PGM-recovery from spent catalysts is a standard procedure. Nevertheless still big amounts of these materials remain untreated. Furthermore the state of the art process is a very expensive solution and does not offer a recovery of all valuable materials. The present paper introduces a hydrometallurgical recovery method for PGM from spent cata...

Today PGM-recovery from spent catalysts is a standard procedure. Nevertheless still big amounts of these materials remain untreated. Furthermore the state of the art process is a very expensive solution and does not offer a recovery of all valuable materials. The present paper introduces a hydrometallurgical recovery method for PGM from spent catal...

Nowadays, beside typical scraps, more and more special residues from metallurgical processing such as slags, dusts and sludges moved into the center of interest. Due to the relatively high amounts of valuable metals in these materials, difficulties concerning their landfilling as well as high metal prices such residues already started to become int...

The recycling industry today accepts more and more secondary resources (dusts, sludges, slags, ...) as raw material for the production. The main difference to ore concentrates is the complex structure and morphology of such residues and a variety of difficult impurities contained in them. Due to that, the Christian Doppler Laboratory is investigati...

Today the waelz process is the most used facility for recycling of zinc bearing residues, especially dusts from the steel industry, but also neutral leaching residues or in smaller amounts some further complex residues. Typically the zinc is vaporized during the process and collected as zinc oxide in the bag house filter. Next to the product also i...

Due to again rising metal prizes compared with stricter environmental legislations the recycling of residues from metallurgical industry is still an important topic for research and development. A successful development of new processes for an economical treatment of such residues is based on the behaviour of these materials concerning reduction, m...

Increasing environmental regulations and rising dumping costs in combination with sustainability are finally resulting in the recycling of residues from the metallurgical industry. The common aim of companies is the “Zero-Waste-Circuit”, which means a closed recycling circle of all products of a processing route and a reuse of perhaps pre-treated b...

Typical carbonization units have the target to produce a charcoal which is in nearly all cases used as energy carrier for the production of heat in different forms. These often very old and not efficient processes are in most cases operated at temperatures between 350 and 500 �C and generate a charcoal with only medium quality. To realize an applic...

Due to always getting stricter environmental legislations as well as increasing land filling fees the efforts for treating residues from metallurgy are increasing. In case of filter dusts from metallurgical industry the high zinc bearing EAF-dusts are one main source for the recovery of secondary zinc. Although the waelz kiln is state of the art, t...

In times of increasing costs for landfilling, metal prices as well as always getting higher metal consumptions worldwide, sustainability and economic utilization of resources is a principal point in the development and improvement of recycling methods. The Christian Doppler Laboratory at the department of nonferrous metallurgy at the University, Le...

Due to always getting stricter environmental legislations as well as increasing land filling fees the efforts for treating residues from metallurgy are continuously increasing. In case of filter dusts from metallurgical industry the high zinc bearing EAF-dusts or also dusts from copper secondary industry are important sources for the recovery of se...

The recycling of steel mill dusts is getting more and more important. The costs and requirements of land filling are rising and companies are interested in new recycling strategies. The rising of sustainability hand in hand with the high rate of valuable metals in these residues supports new research activities on the recycling sector. Especially z...

Metal production and recycling industries are typically characterized by a high demand on energy. Besides this, at the reduction processes necessary in metallurgy additionally high amounts of reducing agents are used in this field of industry. Normally this high demand on carbon is covered by fossil carbonaceous materials, which results in high amo...

In the last years the environmental legislations are continuously getting stricter. Hand in hand an increase of land filling fees lead to higher efforts in treating residues because of sustainability reasons and cost effectiveness. In case of filter dusts from metallurgical industry, the high zinc-bearing electric arc furnace dusts or also dusts fr...

Because of low capacity in primary zinc metallurgy, high efforts in treating secondary raw materials (like waelz oxide) to comply with requirements of the high purity ZnO market are arising. The possibility to treat such materials in an appropriate way to form a quality that can be sold e.g. to rubber and tire industry, to ceramics industry or can...

Because of low capacities for secondary zinc oxide concentrates in primary zinc metallurgy, the upgrading of such concentrates to a quality that meets the requirements of high quality (technical) zinc oxide moves more and more into the focus of future developments. The option to treat such materials in an appropriate way to form a quality that can...

As environmental legislation has become stricter in recent decades, efforts for treating residues have also increased. The existing pyrometallurgical reprocessing methods for metal-containing wastes recover mainly only one valuable metal or produce low-grade byproducts. The aim of developing an economic process has to be the simultaneous recovery o...

The efficiency of recycling processes and the quality of the products often depend on the characteristics of the charged materials. In the case of zinc recycling, beside scrap, complex materials like filter dusts and leaching residues have also to be taken into consideration. In most cases only limited information is available concerning the smelti...

Zinc can be found in various residues from metallurgical industry especially in slags and dusts. While such materials were only a minor source for zinc recycling in the past, they have become more and more interesting during the last years, especially in industrialized countries, where a dumping is ecologically and economically difficult. The paper...

Based on the fact that in the last years the environmental legislation got tougher the efforts for treating residues increased enormously. Today the main treatment for zinc containing residues is the waelzkiln process. Even though it is state of the art there are some disadvantages like the recovery of only one metal or high amounts of slag. A good...

Today various metal containing residues, especially those from metallurgical processes, came in the centre of interests because of environmental legislation as well as the high value of metals contained in the material. For the recycling of these secondary raw materials still some processes are available and a lot of new concepts are under developm...

Hydrogen shows a lot of different advantages as reducing agent for metallurgical purposes. Fast reaction rates as well as the formation of easy condensable water damp are the most important benefits. But nevertheless the high price of hydrogen compared to the alternatively used carbon is the reason why today hydrogen only plays a minor role in meta...

The efforts for treating residues are increasing as a result of the always getting tougher environmental legislations in the last decades as well as other restrictions like the REACH-regulation in the European Union. When looking at the existing treatment methods, mainly only one metal is recovered, in the majority of cases by pyrometallurgical re...

Die Aufarbeitung von zinkhältigen Rückständen aus der Metallurgie stellt heute eine wesentliche Herausforderung hinsichtlich technologischer Umsetzung und Wirtschaftlichkeit dar. Die zu verarbeitenden Materialien stammen aus verschiedenen Bereichen der Metallurgie und zeigen zum einen eine Reihe von Gemeinsamkeiten, zum anderen aber auch Unterschie...