Substance Flow Analysis of Zinc Associated with Iron and Steel Cycle in Japan, and Environmental Assessment of EAF Dust Recycling Process

Nakajima, Kenichi; Matsubae, Kazuyo; Nakamura, Shinichirô; Itoh, Shinji; Nagasaka, Tetsuya

doi:10.2355/isijinternational.48.1478

Cited by 40 publications

(23 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As it has been indicated by the authors, 2) life cycle energy consumption and CO 2 emission for the dust treatment may be much improved by the LAMS process since this process is basically carbon reduction free process.…”

Section: Reaction Of Dust With Caomentioning

confidence: 89%

“…The basic principle of the Waelz process is a carbothermic reduction of zinc-ferrite (ZnFe 2 (Received on May 29, 2008; accepted on July 14, 2008 ) Waelz rotary kiln and the formed metallic zinc subsequently evaporates into the gas phase at high temperature around 1 473 K (1 200°C). Halogens or halides volatilize jointly with the zinc and it is another function of this process while it is not discussed in this paper.…”

Section: Basic Principlementioning

confidence: 99%

“…The authors 2) have pointed out in their analysis of substance flow of zinc through Japanese iron and steel industry that EAF dust generation and the amount of zinc accompanied with the dust in 2005 have been estimated as 0.433ϫ10 6 ton and 0.865ϫ10 5 ton-Zn, respectively. Among total zinc in EAF dust, 0.495ϫ10 5 ton of zinc is estimated to be recovered as crude zinc oxide (ZnO) by the intermediate treatment processes.…”

Section: Introductionmentioning

confidence: 99%

“…However, some problems are pointed out from environmental aspects. 2,3,27) The objective of the present work is to establish the basic principle of the new EAF dust treatment process which enables to recover crude zinc oxide from the dust without carbothermic reduction.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

New EAF Dust Treatment Process with the Aid of Strong Magnetic Field

et al. 2008

Self Cite

View full text Add to dashboard Cite

A new EAF dust treatment process named as "Lime Addition and Magnetic Separation Process (LAMS Process)" has been proposed to recover zinc oxide from the dust and to use solid residue as a flux for steel refining. The LAMS Process consists of the reaction of EAF dust with CaO followed by the adequate crushing and high gradient magnetic separation. The basic principle of this process has been established by revealing the phase equilibria in the CaO-Fe 2 O 3 -ZnO system where Ca 2 Fe 2 O 5 can be in equilibrium with pure ZnO rather than ZnFe 2 O 4 , which is the major component of EAF dust, at higher CaO region. The conversion of zinc ferrite in EAF dust to ZnO and Ca 2 Fe 2 O 5 has been experimentally demonstrated by heating the dust with double molar amount of CaO at 1 173 and 1 373 K. It has also been demonstrated that the formed ZnO and Ca 2 Fe 2 O 5 can be separated by the strong magnetic field. Therefore, it may be possible to recover ZnO from EAF dust without the carbothermic reduction like Waelz process.

show abstract

Section: Reaction Of Dust With Caomentioning

confidence: 89%

Section: Basic Principlementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

New EAF Dust Treatment Process with the Aid of Strong Magnetic Field

et al. 2008

Self Cite

View full text Add to dashboard Cite

show abstract

“…In ferrous metallurgy, Zn, which is distributed in the gas phase and collected as crude ZnO, is recovered by an intermediate process such as the Waelz process and used as a raw material for zinc metallurgy. 31) However, in ferrous metallurgy, recovering elements distributed in the metal phase is not economically feasible, and hence, this is not presently in practice. Therefore, for the beneficial use of elements, it is important to develop a pre-sorting system and accurately define scrap specifications by taking into account the elements contained in the e-waste.…”

Section: Distribution Of Elements Among Gas Slag and Metal Phases Dmentioning

confidence: 99%

Evaluation Method of Metal Resource Recyclability Based on Thermodynamic Analysis

et al. 2009

Self Cite

View full text Add to dashboard Cite

Currently, several metals are commercially recycled from by-products and wastes by metallurgical processing. However, the metallurgical process has each characteristic, which causes limitation for resource recovery. The combinations of elements in secondary resources, such as byproducts and wastes, are often different from those in natural resources. There are even combinations that are not present in natural resources. Conventional metallurgical processes have been optimized for economical and efficient extraction of desired elements only from large amount of ores under constant grade. Therefore, in order to extract metals from secondary resources by the conventional metallurgical process, it is necessary to estimate the recoverability of the constituent elements by taking into account their chemical properties well in advance. In particular, analysis for combination of elements is significantly important.In this study, we developed the evaluation method of metal resources recyclability based on thermodynamic analysis, and made clear the element distribution among gas, slag and metal phases during metal recovery based on thermodynamic analysis. In an application of the method shows that Cu, and precious metals (Ag, Au, Pt, Pd) present in mobile phones can be recovered as metals in the pyrometallurgy process of Cu in a converter, while Pb and Zn can be recovered as vapor. Other elements distributed in the slag phase are difficult to recover. The result of our analysis reflects the trends observed in the distribution of metals in copper metallurgy, thereby indicating the validity of our proposed evaluation method.

show abstract