scholarly journals Process Improvements for Direct Reduced Iron Melting in the Electric Arc Furnace with Emphasis on Slag Operation

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 402
Author(s):  
Marcus Kirschen ◽  
Thomas Hay ◽  
Thomas Echterhof

Steelmaking based on direct reduced iron (DRI, and its compacted derivative hot briquetted iron, HBI) is an anticipated important global alternative to current steel production based on FeOx reduction in blast furnaces due to its lower specific CO2 emission. The majority of DRI is melted and refined in the electric arc furnace with different process conditions compared to the melting of steel scrap due to its raw material composition being rather different. We provide data and analysis of slag composition of DRI charges vs. steel scrap charges for 16 industrial electric arc furnaces (EAFs). Suggestions for optimized slag operation and resulting process improvements of DRI melting in the EAF are given. A dynamic mass and energy model of the DRI melting in the EAF is introduced to illustrate the implications of the adapted slag operation on the EAF process with DRI charges.

2011 ◽  
Vol 378-379 ◽  
pp. 719-722 ◽  
Author(s):  
Zorica Bacinschi ◽  
Cristiana Zizi Rizescu ◽  
Elena Valentina Stoian ◽  
Dan Nicolae Ungureanu ◽  
Aurora Anca Poinescu ◽  
...  

The processing and recycling experiments of dust from Electric Arc Furnace (EAF) in industrial conditions aimed at highlighting the minimizing possibility of this waste by transforming it into a by-product that can represent either a secondary raw material for steel making in EAF or to recover iron, zinc and lead (the Waltz process). Electric-arc furnace dust (EAFD) is a by-product of steel production and recycling. This fine-grained material contains high amounts of zinc and iron as well as significant amounts of potentially toxic elements such as lead, cadmium and chromium. Therefore, the treatment and stabilization of this industrial residue is necessary. Leaching test is a method of evaluating the impact of waste that is stored (soil, water table).


2012 ◽  
Vol 57 (3) ◽  
pp. 811-821 ◽  
Author(s):  
T. Sofilic ◽  
J. Jendričko ◽  
Z. Kovačevic ◽  
M. Ćosić

Electric arc furnace (EAF) steel manufacturing is an important recycling activity which contributes to the recovery of steel resources and steel scrap/waste minimization. Because of the content of plastics, coatings and paintings as well as other nonferrous materials in the charge during melting, a strong emission of pollutants, including polluting substance group consists of persistent organic pollutions (POPs) represented by polycyclic aromatic hydrocarbon (PAH), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) occurs. This study was set out to investigate emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/Fs) from the stack of a new electric-arc furnace-dust treatment plant installed during modernisation of the Melt Shop in CMC SISAK d.o.o., Croatia. Obtained results have been compared with previously obtained results of PCDDs/Fs emission measurements from the old electric-arc furnace dust treatment without dust drop-out box, as well as quenching tower. The total PCDDs/Fs concentration in the stack off gases of both electric arc furnaces EAF A and EAF B were 0.2098 and 0.022603 ng I-TEQ/Nm3 respectively, and these results are close to previous obtained results by other authors. The calculated values of the emission factors for PCDDs/Fs calculated on the basis of measured PCDDs/Fs concentration in the stack off gases in 2008 and 2011 were 1.09 and 0.22 ng I-TEQ/ ton steel, respectively.


2015 ◽  
Vol 22 (S1) ◽  
pp. 10-16 ◽  
Author(s):  
Qi-xing Yang ◽  
An-jun Xu ◽  
Peng Xue ◽  
Dong-feng He ◽  
Jian-li Li ◽  
...  

2019 ◽  
Vol 108 (1) ◽  
pp. 64-76
Author(s):  
H. A. Abdelwahed ◽  
M. Shaheen ◽  
G. M. Megahed ◽  
E. Ahmed ◽  
M. Meraikib

Author(s):  
Ebrahim Hajidavalloo ◽  
Hamzeh Dashti

In this paper, energy and exergy analysis of an existing steel electric arc furnace (EAF) was performed to estimate the furnace potential for increasing the efficiency and decreasing the electrical energy consumption. The results of analysis show that the energy and exergy efficiencies of the furnace are 56.9% and 40.5%, respectively. Field data show that mass flow rate of hot flue gas is around 10.4 kg/s in average which contains 18.3% and 12.2% of total input energy and exergy, respectively. By using energy of flue gas for preheating the sponge iron, electrical energy consumption of the furnace could be reduced up to 88 GJ which means 21.2% reduction in electrical energy consumption and 13.6% increase in steel production. Also, exergy efficiency improves about 10.8% by using preheating scheme.


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.


2017 ◽  
Vol 6 (3) ◽  
Author(s):  
Katya Brunelli ◽  
Pietrogiovanni Cerchier ◽  
Renato Bonora ◽  
Manuele Dabalà

AbstractIn this work, nanoparticles of ZnO and zero-valent Fe were sonochemically synthesised using a solution produced from electric arc furnace dust leaching as raw material. The leaching was previously carried out using ultrasound with various concentrations of sulphuric acid. The resulting solutions contained, in addition to varying amounts of Zn and Fe, elements such as Cr, Mn, Mg, Ca, and Si. Two methods were developed, one for Fe and one for ZnO, to obtain the nanoparticles and to avoid the precipitation of the additional elements during the nanoparticle production. The synthesis of ZnO nanoparticles was performed through the formation of a precursor by sonochemical reaction with NaOH, and the thermal decomposition of this precursor by heating in furnace. The production of Fe nanoparticles involved the precipitation of FeOOH, the dissolution of FeOOH in HCl solution, and the ultrasound-assisted reduction of the iron ions with NaBH


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