Evaluation of the Leaching Behavior of Hexavalent Chromium from Malaysian Electric Arc Furnace Steel Slag

2013 ◽  
Vol 652-654 ◽  
pp. 1628-1632 ◽  
Author(s):  
Kolawole Bankole Lateef ◽  
Abdul Rezan Sheikh ◽  
Mohd Sharif Nurulakmal ◽  
Norlia Baharun

This study investigates the leaching behavior of hexavalent chromium (Cr (VI)) from both industrial electric arc furnace steel slag and steel slag modified with up to 2% wt Cr2O3. The study was performed with European standard batch leaching test for 15 days and the lixiviant used were alkaline, de-ionized and rain water. The experimental work was also complimented with slag characterization using XRF, XRD and SEM/EDX analysis. After 15 days, Cr (VI) was found to be highest in rain water (0.016 mg/L) and lowest in de-ionized water (0.002 mg/L). With more Cr2O3 in EAF slag, more Cr will leach out based on the 2% wt Cr2O3 addition. Besides the lixiviant used, slag stirring speed and liquid to solid ratio also affect the dissolution of Cr (VI). With up to 2 wt % Cr2O3 in EAF slag, Cr (VI) dissolution was still lower than the threshold of 0.1 mg/L set by USEPA for public water systems. The analysis also indicated that the relative amounts of soluble basic and acidic oxides in the slag will affect the dissolution of Cr (VI).

2018 ◽  
Vol 7 (3.23) ◽  
pp. 1 ◽  
Author(s):  
Siti Zu Nurain Ahmad ◽  
Hamdan R ◽  
Wan Afnizan Wan Mohamed ◽  
N Othman ◽  
Nur Shaylinda Mohd Zin

Electric arc furnace (EAF) slag as filter media has been extensively used nowadays for wastewater treatment technology. Steel slag was produced as byproduct from steelmaking processes. However, different batches of steel slag production produce different composition. Thus, this study determined the chemical composition, pH value and points of zero charge (PZC) of two different samples of electric arc furnace (EAF) slag; high iron EAF slag (Slag HFe) and high calcium EAF slag (Slag HCa). The steel slag were characterized using X-ray Fluorescence Spectroscopy (XRF) analysis for the chemical composition, extraction with boiling water for pH value, and salt addition method for PZC. Slag HFe was mainly consisted of 38.2% ferric oxide and 20.4% calcium oxide, 10.20 pH value and pH 10.55 for PZC. While for Slag HCa, they were composed of 1.64% ferric oxide and 49.5% calcium oxide of pH value of 11.11 and pH 11.75 for PZC. Therefore, Slag HCa was considered as a more basic species compared to Slag HFe. 


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.


2011 ◽  
Vol 40 (4) ◽  
pp. 1153-1161 ◽  
Author(s):  
Radmila Milačič ◽  
Tea Zuliani ◽  
Tina Oblak ◽  
Ana Mladenovič ◽  
Janez Šč ančar

2019 ◽  
Vol 116 (2) ◽  
pp. 217
Author(s):  
Xiang Lu ◽  
Wenbin Dai ◽  
Xiaoming Liu ◽  
Daqiang Cang ◽  
Liang Zhou

Electric arc furnace steel slag was modified by wastes in hot-stage process with the aim to improve the cementitious activity. Effect of basicity on cementitious activity of modified steel slag was investigated in this research. The modified slag was characterized by XRD, DTA and Raman spectra techniques to investigate the correlations between structural features and the cementitious activity. The results showed that modified steel slag with a basicity index of 1.67 possessed the highest activity index, 107%, due to the precipitation of Belite, high content of amorphous phase and low polymerization degree. The polymerization degree of modified slag was demonstrated by nonbridging oxygen per tetrahedrally coordinated cations value which was calculated through curve-fitted Raman spectra. The value of modified slag increased as the basicity promoted from 1.05 to 1.67, indicating a lower degree of polymerization. Modified slag with a basicity index of 1.86 possessed the poor cementitious activity mainly because of the significant decrease of glass phase content.


2011 ◽  
Vol 196 ◽  
pp. 287-294 ◽  
Author(s):  
R.I. Iacobescu ◽  
D. Koumpouri ◽  
Y. Pontikes ◽  
R. Saban ◽  
G.N. Angelopoulos

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