Turning Electric Arc Furnace Dust Waste into Oil Spot Ceramic Glaze

2016 ◽  
Vol 690 ◽  
pp. 33-38 ◽  
Author(s):  
Wantanee Buggakupta ◽  
Chanyanud Tianthong ◽  
Sirithan Jiemsirilers

Electric Arc Furnace (EAF) is commonly used in steel recycling industries. Apart from steel metal product, a waste in the form of dust is also produced and so called EAF dust. The fine particulates mainly contain zinc-iron oxides along with a small amount of heavy metals like chromium and lead, and have been categorized as a toxic waste. Proper treatments can be crucially required in order to recover crude zinc oxide and iron oxide from the dust; however, no practical recycling plants have been now readily operated in Thailand. To reduce its toxicity, EAF dust could be mixed with silica-based materials and vitrified into glass. Therefore, EAF dust can possibly be employed as a ceramic glaze raw material. This work pointed out how to make decorative “oil spot” ceramic glaze by substitution of EAF dust for a conventional iron oxide. The prepared glaze mixtures were applied over the ceramic bodies and fired at 1250 °C in oxidation atmosphere. The as-fired glaze appearances with tiny and silvery crystals floating over dark brown based-glaze were exhibited. Phase content and characteristics of the obtained glaze were analyzed. The roles of zinc oxide to iron oxide ratios on oil spot and crystal generation was concerned. A comparison of oil spot effects due to different iron oxide sources was presented and discussed. Oil spot glaze made from a combination of EAF dust and iron oxide powder was also proposed.

2021 ◽  
Vol 945 (1) ◽  
pp. 012027
Author(s):  
Hwang Sheng Lee ◽  
Yao Yi Teo

Abstract Electric arc furnace (EAF) dust waste is generated during EAF steelmaking process. Zinc and iron which comprise the highest composition in EAF dust are secondary resources for making steel products. They mainly present in the form of stable zinc ferrite (ZnFe2O4), leading to the extraction process difficult. In this study, a combined hydro-pyrometallurgical process was developed to extract both zinc oxide and iron oxide from EAF dust. Initially, hydrometallurgical leaching was used to leach zinc and iron from EAF dust. Results show that 10 M of hydrochloric acid (HCl) at 25°C can achieve zinc and iron leaching of 92% and 91%, respectively. The liquid solution post leaching was subjected to pyrometallurgical process to form Fe2O3 mixture at 250°C while retaining zinc chloride (ZnCl2) as solid residue. Then, the obtained ZnCl2 was treated with sodium hydroxide (NaOH) and nitric acid (HNO3) to form ZnO. The Fe2O3 and ZnO extraction were 2.5 g and 1.5 g, respectively out of 10 g of EAF dust with their respective purity of 87% and 98%. The developed process can provide new insight into recovering zinc oxide and iron oxide simultaneously from EAF dust, thereby paving the way to circular economy development and sustainable steel dust waste management for steel industries.


2015 ◽  
Vol 656-657 ◽  
pp. 428-433
Author(s):  
Sureerat Polsilapa ◽  
Piyakarnt Khamsriraphap ◽  
Panyawat Wangyao

Electric arc furnace dust is a byproduct from steelmaking, contained up to 50%wt of zinc ferrite. It also contains about 10-20%wt of zinc oxide and the other metal oxides. Approximately 100,000 tons of EAF dust are generated per annum within Thailand. All of the dust has been sent to landfill. The objective of this research is to investigate the kinetics mechanism of the decomposition of zinc ferrite in EAF dust to obtain zinc oxide and iron oxide by using iron powder as a reducing agent. The process was carried out by mixing zinc ferrite or EAF dust with iron powder then compressed them in a mold. The samples from compression were treated by pyrometallurgical process. The factors required to be concerned were temperatures, particle sizes of iron powder, and mole ratios of zinc ferrite per iron powder, respectively. The treated samples were analyzed by X-ray diffraction (XRD) in order to characterize zinc ferrite phase transformation. It was found that the quantity of zinc ferrite, both either pure zinc ferrite and zinc ferrite in EAF dust, were decreased after treating by the pyrometallurgical process when increasing treating time from 30 to 180 minutes at 600°C, the particle size of iron powder at 10 micron, and the mole ratio of zinc ferrite per iron powder at 1:3. Moreover about 70%wt of zinc ferrite was decomposed and the products obtained were zinc oxides (ZnO) and iron oxides (Fe3O4, FeO, Fe2O3). The reduction of zinc ferrite with iron powder was well-defined taking place by diffusion thru product layer control. The activation energy of the reduction process was found to be 47.21±2.83 kJ/mol. Therefore, the decomposition of zinc ferrite by iron powder could be carried out at 1 atm with low pyrometallurgical temperature (600°C) and equipped with hydrometallurgical process to obtain high zinc yield.


2019 ◽  
Vol 8 (6) ◽  
pp. 5504-5514 ◽  
Author(s):  
Vanessa S. Silva ◽  
Juliana S. Silva ◽  
Bruno dos S. Costa ◽  
Clayton Labes ◽  
Rosane M.P.B. Oliveira

Metals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1347 ◽  
Author(s):  
Pao Ter Teo ◽  
Siti Koriah Zakaria ◽  
Siti Zuliana Salleh ◽  
Mustaffa Ali Azhar Taib ◽  
Nurulakmal Mohd Sharif ◽  
...  

Steel slag is one of the most common waste products from the steelmaking industry. Conventional methods of slag disposal can cause negative impacts on humans and the environment. In this paper, the process of steel and steel slag production, physical and chemical properties, and potential options of slag recycling were reviewed. Since steel is mainly produced through an electric arc furnace (EAF) in Malaysia, most of the recycling options reviewed in this paper focused on EAF slag and the strengths and weaknesses of each recycle option were outlined. Based on the reports from previous studies, it was found that only a portion of EAF slag is recycled into more straightforward, but lower added value applications such as aggregates for the construction industry and filter/absorber for wastewater treatments. On the other hand, higher added value recycling options for EAF slag that are more complicated such as incorporated as raw material for Portland cement and ceramic building materials remain at the laboratory testing stage. The main hurdle preventing EAF slag from being incorporated as a raw material for higher added value industrial applications is its inconsistent chemical composition. The chemical composition of EAF slag can vary based on the scrap metal used for steel production. For this, mineral separation techniques can be introduced to classify the EAF slag base on its physical and chemical compositions. We concluded that future research on recycling EAF slag should focus on separation techniques that diversify the recycling options for EAF slag, thereby increasing the waste product’s recycling rate.


2015 ◽  
Vol 36 (2) ◽  
pp. 263-271 ◽  
Author(s):  
Aneta Magdziarz ◽  
Monika Kuźnia ◽  
Michał Bembenek ◽  
Paweł Gara ◽  
Marek Hryniewicz

Abstract Dust generated at an electric arc furnace during steel production industry is still not a solved problem. Electric arc furnace dust (EAF) is a hazardous solid waste. Sintering of well-prepared briquetted mixtures in a shaft furnace is one of possible methods of EAFD utilisation. Simultaneously some metal oxides from exhaust gases can be separated. In this way, various metals are obtained, particularly zinc is recovered. As a result, zinc-free briquettes are received with high iron content which can be used in the steelmaking process. The purpose of the research was selecting the appropriate chemical composition of briquettes of the required strength and coke content necessary for the reduction of zinc oxide in a shaft furnace. Based on the results of the research the composition of the briquettes was selected. The best binder hydrated lime and sugar molasses and the range of proper moisture of mixture to receive briquettes of high mechanical strength were also chosen and tested. Additionally, in order to determine the thermal stability for the selected mixtures for briquetting thermal analysis was performed. A technological line of briquetting was developed to apply in a steelworks.


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