Thermochemical Calculation of the Quaternary CaO-SiO2-Al2O3-MgO System at 1600°C for Predicting the MgO-Saturation and MgO-MgO · Al2O3Equilibrium of Secondary Metallurgical Slag

2013 ◽  
Vol 85 (4) ◽  
pp. 564-569 ◽  
Author(s):  
Jürgen Goriupp ◽  
Johannes Schenk ◽  
Gerald Klösch ◽  
Martin Hiebler
Keyword(s):  
Metallurgical Slag ◽  
Thermochemical Calculation

THE TREATMENT AND MINIMIZATION OF METALLURGICAL SLAG AS WASTE

2010 ◽  
Vol 9 (1) ◽  
pp. 101-106 ◽  
Author(s):  
Igor Cretescu ◽  
Maria Cioroi ◽  
Licuta Nistor Cristea
Keyword(s):  
Metallurgical Slag

JUSTIFICATION OF THE USE OF METALLURGICAL SLAGS AS A BACKFILL MATERIAL FOR QUARRY CAVITIES

2021 ◽  
pp. 15-25
Author(s):  
Volodymyr Bondarenko ◽  
◽  
Oleksandr Filonenko ◽  
Mykhailo Petlovanyi ◽  
Vladyslav Ruskykh ◽  
...  
Keyword(s):  
Blast Furnace ◽  
Large Scale ◽  
Experimental Studies ◽  
Metallurgical Slag ◽  
Open Pit ◽  
Practical Significance ◽  
Steel Smelting ◽  
Backfill Material ◽  
Steel Making ◽  
Metallurgical Slags

Purpose. Experimental studies of the interaction of blast-furnace and steel-making slags with open pit waters during their direct contact and assessment of the volume of filling of the formed man-made cavities during mining of mineral deposits. Methods. Based on the analysis, the current low level of metallurgical slag and the lack of real and effective directions of their large-scale utilization were determined. The laboratory studies of the interaction of metallurgical slags with open pit water at a certain time of interaction, generally accepted methods for studying the chemical composition and concentration of substances in water, computer-aided design software packages and drawings to determine the volumes of the open pit mined-out area were used. Results. The dynamics of changes in the products of interactions of steel-smelting slags with open-pit waters at a certain ratio and period of interaction was investigated. It was found that the concentration of pollutants upon contact of water with steel-making slag changes according to polynomial dependences on the time of their interaction, decreasing by the 30th day, which eliminates the danger for the aquifer. The safest type of metallurgical slag was recommended for the formation of the bottom layer of the backfill massif. The volumes of the mined-out area of the open pit were determined in detail to assess the volumes of placement of the backfill material based on metallurgical slags. Scientific novelty. The safety of the contact of backfill materials based on steelmaking slags with open pit water was scientifically proven, which is confirmed by the established polynomial patterns of changes in concentrations and pollutants from the ratio and time of interaction. Practical significance. The formation of the backfill massif on the basis of blast-furnace dump and steel-smelting slags will allow achieving an environmental effect, such as their safe disposal as a reclamation of technologically disturbed lands by mining and restoration of the economic value of the land plot, as well as preventing the formation of new dumps.

Research on the Recovery of Copper from Metallurgical Slag

Mining Revue ◽  
2021 ◽  
Vol 27 (3) ◽  
pp. 40-44
Author(s):  
Eugen Traistă ◽  
Camelia Bădulescu ◽  
Maria Lazăr ◽  
Camelia Traistă
Keyword(s):  
Metallurgical Slag ◽  
Industrial Wastes ◽  
Raw Material ◽  
Pollutant Emissions ◽  
Material Base ◽  
Metallurgical Slags ◽  
Slag Processing ◽  
Metallurgical Processes ◽  
Initial Research ◽  
Over Time

Abstract Metallurgical slag is one of the most common industrial wastes. Many of these wastes are not stable over time, by reacting with water and air, continuously generating emissions of heavy metals. Metallurgical slag processing is necessary for at least two reasons: reducing pollutant emissions and broadening the raw material base. The recovery of these slags is very difficult because they are the result of metallurgical processes that aimed to fix metals considered impurities in chemical matrices as stable as possible. This paper presents the initial research on the behavior of metallurgical slags against different leaching technologies.

scholarly journals Enhancing Arsenic Solidification/Stabilisation Efficiency of Metallurgical Slag-Based Green Mining Fill and Its Structure Analysis

Metals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1389
Author(s):  
Wei Gao ◽  
Zifu Li ◽  
Siqi Zhang ◽  
Yuying Zhang ◽  
Pingfeng Fu ◽  
...  
Keyword(s):  
High Efficiency ◽  
Calcium Nitrate ◽  
Outer Sphere ◽  
High Specific Surface Area ◽  
Sodium Sulphate ◽  
Metallurgical Slag ◽  
Hydration Reaction ◽  
Mechanism Analysis ◽  
Low Carbon ◽  
Sphere Complex

To dispose of arsenic-containing tailings with low carbon and high efficiency, sodium sulphate (Na2SO4), sodium hydroxide (NaOH), calcium nitrate Ca(NO3)2 and calcium hydroxide Ca(OH)2 were independently added to metallurgical slag-based binder (MSB) solidification/stabilisation (S/S)-treated tailings (MSTs) to enhance the MST arsenic S/S performance. Results showed that only Ca(OH)2 could increase the unconfined compressive strength of MST from 16.3 to 20.49 MPa and decrease the leachate As concentration from 31 μg/L to below 10 μg/L. Na3AsO4·12H2O and NaAsO2 were used to prepare pure MSB paste for mechanism analysis. The results of microstructure analyses showed the high specific surface area and amorphous properties of calcium–sodium aluminosilicate hydrate facilitated the adsorption or solid-solution formation of As(V) and As(III). As(V) formed an inner-sphere complex in ettringite, whereas As(III) formed an outer-sphere complex, and the relatively larger size and charge of As(V) compared with SO42− restrict substitution inside channels without affecting the ettringite structure under high loading of As(V). The added Ca(OH)2 promoted the hydration reaction of MSBs and facilitated the formation of a Ca–As(V) precipitate with low solubility, from Ca4(OH)2(AsO4)2·4H2O (Ksp = 10−27.49) to Ca5(AsO4)3(OH) (Ksp = 10−40.12). This work is beneficial for the application of cement-free MSB in the S/S process.

AM1 studies on the stabilities of anionic σ-complex regioisomers: thermodynamics of regioselectivity in the reaction of methide, methoxide, and hydroxide anions with electron-deficient aromatics

1994 ◽  
Vol 72 (7) ◽  
pp. 1709-1721 ◽  
Author(s):  
Erwin Buncel ◽  
Richard M. Tarkka ◽  
Julian M. Dust
Keyword(s):  
Gas Phase ◽  
Global Minimum ◽  
Condensed Phases ◽  
Am1 Calculations ◽  
Calorimetric Data ◽  
Electron Pairs ◽  
X Ray ◽  
Carbon Nucleophiles ◽  
Meisenheimer Complexes ◽  
Thermochemical Calculation

Heats of formation (ΔHf) for a series of aromatics that are progressively more electron deficient (benzene, 6; nitrobenzene, 7; 4-fluoronitrobenzene, 8; 1,3-dinitrobenzene, 9; 2,4,6-trinitroanisole, 2; and 1,3,5-trinitrobenzene, 1) were determined by semiempirical AM1 calculations. As a probe of the factors that govern the regioselectivity exhibited in the formation of anionic σ-adducts (Meisenheimer complexes), experimental gas-phase ΔHf values for the prototypical oxygen and carbon nucleophiles (hydroxide, methoxide, and methide anions) were used in a thermochemical calculation along with the calculated ΔHf of the electrophiles and the adducts to determine the heats of complexation (ΔHc). The present results show that for the series of nitroaryl electrophiles, 7, 9, and 1, hydroxide and methide anions exhibit the same regioselectivity based on thermodynamics of Meisenheimer complex formation. Specifically, Meisenheimer complexes derived from attack at a position para to at least one nitro group (designated MC-4) are formed with the greatest exothermicity (ΔHc). Exothermicity of complexation increases for both hydroxide and methide adduct formation as the number of nitro groups in the electrophile is increased, from 7 to 9 and to 1, but formation of the methide adducts occurs uniformly with greater exothermicity than that of hydroxide adducts. These results are considered in light of solution calorimetric data that quantify adduct stability in condensed phases. Surprisingly, it is found that regioselectivity inverts for CH3−as compared to OH−and CH3O−in complexation with 2,4,6-trinitroanisole, 2. Thus, while methoxide and hydroxide form adducts at C-1 of TNA with higher exothermicity than at C-3, methide preferentially forms an adduct at C-3 according to the same enthalpy criterion. These results arise from the degree of stereoelectronic stabilization that may be imparted to the respective Meisenheimer complexes formed from ipso attack, that is, the adducts (MC-1) that are geminally disubstituted with electronegative heteroatom groups. For the methoxide MC-1 of TNA, 2, full stereoelectronic stabilization is provided by n–σ* donation from nonbonding electron pairs of the acetal-like methoxyl moieties to suitable C—O acceptor bonds. However, the methide moiety of the comparable MC-1 of TNA cannot partake in such an interaction and, so, with methide, MC-3 formation is preferred over MC-1. Further evidence is provided by consideration of the two energy minima obtained from optimization of the geometry of the oxygen-centred adducts formed by attack of methoxide at C-1 of TNA, 2. In the presence of a point charge that simulates an ion-paired cation, an "M-shaped" conformer is favoured for MC-1, while in the absence of a counterion the "S-shaped" conformer is favoured. Without a complexing counterion M and S conformers are both local minima, while the "S" conformer constitutes the global minimum. The AM1 optimized structure for the "M" conformer compares favourably to published X-ray data. The greater exothermicity of formation of the "S" conformer in the absence of the counterion is indicative of stereoelectronic stabilization of the O-adduct. The geometry is rationalized as a result of minimizing steric repulsion and maximizing the n-σ* stabilization of the C-1 adduct.

Site Specific Isolation of a Metallurgical Slag Dump

1990 ◽  
pp. 1217-1218
Author(s):  
E. Adam ◽  
J. Brauns ◽  
H. Hötzl ◽  
F. Lamm ◽  
U. Ritscher ◽  
...  
Keyword(s):  
Metallurgical Slag ◽  
Site Specific ◽  
Slag Dump

Application of metallurgical slag to treat geothermal wastewater with high concentrations of arsenic and boron

2018 ◽  
Vol 16 (5) ◽  
pp. 2373-2384 ◽  
Author(s):  
B. M. Mercado-Borrayo ◽  
M. Solís-López ◽  
R. Schouwenaars ◽  
R. M. Ramírez-Zamora
Keyword(s):  
Metallurgical Slag ◽  
High Concentrations
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