title: Reduction behavior of zinc ferrite in EAF-dust recycling with CO gas as a reducing agent.
abstract: EAF-dust containing metal oxides can be regarded as an important source for zinc and iron. In this study, the reduction behavior of zinc ferrite with CO gas as a reducing agent under different temperatures was investigated to develop a new process for the recovery of zinc and iron from EAF-dust. The results of the phase studies with synthetic franklinite show that zinc substituted wustite, and spinel with low zinc content formed at lower temperatures from 450 to 850 °C due to incomplete zinc-iron-separation. Zinc ferrite was completely reduced to metallic zinc and iron at 950 °C. After evaporation and condensation, metallic zinc was collected in the form of zinc powder while iron, the reduction residue, was obtained in the form of direct reduced iron (DRI). The mass balance indicates a high zinc recovery ratio of over 99%. The new treatment process by thermal reduction with CO gas as a reducing agent achieved higher recovery and metallization grade of both zinc and iron from EAF-dust at lower temperatures than other commercial processes. The metallic products can be used directly as semi-products or as raw materials for refinery.
authors.affiliation: Resource R & D Department, China Hi-Ment Co., Kaohsiung, Taiwan.
authors.forename: Chia-Cheng
authors.initials: CC
authors.lastname: Wu
authors.affiliation: The Experimental Forest, College of Bio-Resources and Agriculture, National Taiwan University, Nan-Tou 55750, Taiwan. Electronic address: d90541003@ntu.edu.tw.
authors.forename: Fang-Chih
authors.initials: FC
authors.lastname: Chang
authors.affiliation: Sustainable Environment Research Center, National Cheng Kung University, Tainan 709, Taiwan.
authors.forename: W-S
authors.initials: WS
authors.lastname: Chen
authors.affiliation: Department of Resources Engineering, National Cheng Kung University, Tainan 701, Taiwan.
authors.forename: Min-Shing
authors.initials: MS
authors.lastname: Tsai
authors.affiliation: The Experimental Forest, College of Bio-Resources and Agriculture, National Taiwan University, Nan-Tou 55750, Taiwan.
authors.forename: Ya-Nang
authors.initials: YN
authors.lastname: Wang
mesh_terms: D004391:Dust; D005290:Ferric Compounds / Q000737:chemistry; D005296:Ferrous Compounds; D007220:Industrial Waste / Q000032:analysis; D007501:Iron / Q000737:chemistry / Q000302:isolation & purification; D008669:Metallurgy; D059027:Recycling; D019163:Reducing Agents / Q000737:chemistry; D018505:Waste Management / Q000379:methods*; D015032:Zinc / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D004391:Dust; D005290:Ferric Compounds; D005296:Ferrous Compounds; D007220:Industrial Waste; D019163:Reducing Agents; C001215:ferrite; D007501:Iron; C034236:ferrous oxide; D015032:Zinc
keywords: EAF-dust; Reduction; Zinc ferrite; Zinc oxide