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All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Formation of Plastic Inclusions in U71Mnk High-Speed Heavy-Rail Steel Refined by CaO-SiO{sub 2}-Al{sub 2}O{sub 3}-MgO Slag

To precisely control the characteristics of nonmetallic inclusions with high plasticity in U71Mnk high-speed heavy-rail steel deoxidized by Si and Mn, the chemical composition of CaO-SiO{sub 2}-Al{sub 2}O{sub 3}-MgO slag in the ladle furnace (LF) refining process was optimized by thermodynamic calculations. Relationships among the refining slag, nonmetallic inclusions, and elemental concentrations in the steels were analyzed to obtain the conditions for determining the optimal composition of refining slag. The optimal compositions and the component activities of CaO-SiO{sub 2}-Al{sub 2}O{sub 3}-MgO refining slag were determined and discussed according to calculations using FactSage 7.0. Finally, ten industrial experiments were performed. Variations in the compositions of LF refining slag, inclusions, and steel, as well as the sizes of the inclusions, and metallographic classification assessment of the U71Mnk steel product, were investigated and discussed to verify the feasibility and effectiveness of the optimized LF refining slag. Kinetics of steel–slag and steel-inclusion reactions during LF refining was studied and compared. The results show that to obtain low [O], [Al], and [S] contents and inclusions with high plasticity in molten steel, the optimal composition of the LF refining slag should be CaO: 44.2 to 51.7 wt pct, SiO{sub 2}: 41.4 to 47.0 wt pct, Al{sub 2}O{sub 3}: 0 to 4.7 wt pct and MgO 5.0 to 7.0 wt pct, where the basicity R is above 1.00 and the C/A ratio is above 9.00. After the LF refining process, the contents of total oxygen (T.O.), [Al], and [S] gradually stabilized in the range of 0.0008 to 0.0012 wt pct, 0.002 to 0.0028 wt pct and 0.0026 to 0.0037 wt pct, respectively. The densities of the three kinds of typical inclusions (CaO-SiO{sub 2}-Al{sub 2}O{sub 3}-MgO, MnS, and CaO-SiO{sub 2}-Al{sub 2}O{sub 3}-MgO-MnS) also decreased and reached approximately 0.25/mm{sup 2}, and no inclusion larger than 6.0 μm was found. The composition of the inclusions gradually changed into the optimal range in the CaO-SiO{sub 2}-Al{sub 2}O{sub 3}-MgO slag system during the LF refining process.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Separation of Phosphorus and Manganese from Steelmaking Slag by Selective Reduction

Steelmaking slag contains considerable amount of manganese (Mn) and phosphorus (P), and recycling them is an important issue. Since Mn is an alloy added to enhance the steel quality, while P is a harmful impurity in the steel product, they need to be separated for recycling. We have already found the possibility of separating Mn and P from steelmaking slag by selectively reducing P{sub 2}O{sub 5} and FeO while suppressing the reduction of MnO. As a fundamental study for the selective reduction of P from steelmaking slag, in this study, we vary the slag basicity, graphite mixing ratio, temperature, and crucible type to find the optimum condition. Artificial steelmaking slag with various compositions is synthesized and mixed with graphite powder in an Al{sub 2}O{sub 3} or a MgO crucible. The reduction is conducted at 1673 K, 1773 K, and 1873 K for 20 to 80 minutes. As a result, carbon saturated metal is formed from the slag, and the reduced metal and slag were separated easily. We find that a decrease in slag basicity suppressed the reduction rate of Mn while enhancing that of P. The activation energy for the reduction rate constant of P is found to be close to that of the diffusion of P in slag.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Carbonaceous Material Properties and Their Interactions with Slag During Electric Arc Furnace Steelmaking

The state of the interface between slag and carbon determines the slag foaming behavior and thus the effectiveness of carbon in electric arc furnace (EAF) steelmaking. This paper explores the interaction between synthetic slag and carbonaceous materials derived from various sources, including bio-char produced by two different technologies, graphite, coke, and char from tire pyrolysis. Different interfacial phenomena were found between slag and the carbonaceous materials examined. The interactions between bio-char and slag are found to be poor in comparison with other carbonaceous materials. Carbonaceous materials were characterized in terms of their chemical composition and the results obtained suggested that interfacial phenomena were not dominated by ash in the carbonaceous material. The effects of carbon crystalline structure on interaction with slag were evaluated by Raman spectroscopy and X-ray diffraction. Surface properties of the samples were evaluated using scanning electron microscopy, and surface morphology was identified as the principal factor affecting the interaction of slag on carbonaceous particles. The smooth surface of bio-char results in reduced slag foaming. This finding forms the basis for future research on the production of bio-char to be used as a slag foaming agent in EAF steelmaking.

36 MATERIALS SCIENCE↗
DOE OSTI2020

A deep insight on the coal ash-to-slag transformation behavior during the entrained flow gasification process

Recent research provided deep insight on the coal ash-to-slag transformation characterization during the entrained flow gasification process, with experimentation on a 40 kg/hr (dry basis) coal-fed opposed multi-burner (OMB) entrained flow gasifier and simulation via FactSage™ software. A general mechanism is presented to relate the gasifier design temperature, ash fluid temperature, and operating temperature with the degree of the slag polymerization. The change of the high temperature zone, the corresponding particle residence time in the high temperature zone, and syngas composition have obvious effects on the slag mineral transformation behavior. Mineral types formed on the wall of the gasifier chamber were mainly anorthite (CaAl 2 Si 2 O 8 ), aluminum oxide (Al 2 O 3 ), and calcium sulfide (CaS). These minerals transformed to anorthite and diopside (CaMgSi 2 O 6 ) at the slag hole zone, while the minerals at the lock hopper were anorthite, orthoclase (KAlSi 3 O 8 ), quartz (SiO 2 ), gypsum (CaSO 4 ), calcite (CaCO 3 ), and halite (NaCl). FactSage™ predicted minerals as anorthite, diopside, orthoclase, and albite (NaAlSi 3 O 8 ), etc., where the slag temperature was below the ash fluid temperature and when the ratios of CO/CO 2 and (CO + H 2 )/CO 2 were lower than 1.0 and 2.0, respectively. By simulation, residual carbon was found to be the dominant factor over syngas composition to cause mineral transformation, and this was verified experimentally. The Ca-based crystals, typically anorthite, was shifted to diopside, near the slag hole zone, and a linear relationship was found between the content ratios of diopside/(anorthite + diopside), CaO/SiO 2 , and (CaO + MgO)/SiO 2 . A dimensionless number, θ, was defined to characterize the changing chemical composition and the degree of slag polymerization, with temperature deviation from the design condition. Three zones of θ were identified and related to the deviation between the actual gasification condition from the design condition. Finally, a low slag polymerization degree corresponded with a higher temperature deviation between the actual condition and design condition, and this proved that increased residual carbon content and changing iron valence state increased the mineral types when the slag temperature was below the ash fluid temperature.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2018

Kinetics Analysis of Boron Removal from Silicon through Reactions with CaO-SiO{sub 2} and CaO-SiO{sub 2}-Al{sub 2}O{sub 3} Slags

Different types of slags have been used to refine silicon, particularly for removing boron impurity from metallurgical grade (MG) silicon. Although a number of slags have been used for silicon refining, there is limited information about boron removal kinetics, particularly during the refining reaction with CaO-SiO{sub 2}-Al{sub 2}O{sub 3} slags. This article investigates the boron removal kinetics using the CaO-SiO{sub 2}-Al{sub 2}O{sub 3} slag systems in the temperature range 1773 K to 1873 K (1500 °C to 1600 °C). All the results obtained in the present study provide a strong indication that the rate limiting step of the slag-silicon reaction kinetics was mass transport in the liquid slag. It was also shown in the study that as the reaction temperature is increased, the mass transfer coefficient is also increased. At any particular reaction temperature, adding alumina in the CaO-SiO{sub 2} slag was shown to decrease the mass transfer coefficient, which is consistent with the substantially higher viscosity of the alumina bearing slags over the CaO-SiO{sub 2} slag. The mass transfer coefficients were determined to be between 1.23 × 10{sup −6} and 2.82 × 10{sup −6} ms{sup −1}, with activation energies between 64 and 109 kJ/mol, respectively.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Characteristics of Slag Infiltration in High-Mn Steel Castings

To determine the composition difference between the solid and liquid films in plant practice for high-Mn steel castings, a reaction experiment was carried out to investigate the composition profile of MnO and SiO{sub 2} in the slag layer. Based on the experimental results, a mathematical model of the mold slag for high-Mn steel was developed to describe the nonuniform infiltration behavior of mold slag during oscillation cycles. Moreover, the effects of uneven slag films on slab lubrication and heat transfer in the mold are discussed. The results show that the concentrations of MnO and SiO{sub 2} over the flux layer have an opposite stair-step distribution, which consists of a reaction layer and nonreaction layer. When the reaction layer thickness is 5 mm, a thicker liquid film is formed between the slab and the mold. The inhomogeneity of the composition in the solid film causes large fluctuations in the heat flux in the mold, resulting in irregular depressions on the shell surface. With a reacting thickness of 10 mm, the reacting slag fills in the gap to generate a thinner solid film, which increases the overall heat flux in the mold. Since mold oscillation combined with slag rim enhances the pressure flow in the vicinity of the meniscus, the liquid slag within 80 mm of the mold wall is mixed and consumed quickly. In contrast, the liquid slag beyond 80 mm from the mold wall with a low velocity stays longer in the liquid pool. The model predictions illuminate the characteristics of slag infiltration during high-Mn steel casting, showing good agreement with plant measurements.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Enhancing CO 2 Mineralization Rate and Extent of Iron and Steel Slag via Grinding

Roughly 10% of the CO 2 emissions from iron and steel making are attributable to the direct release of CO 2 from the thermal decomposition of carbonates to produce flux, mainly CaO, used for impurity removal. Notably, these direct emissions remain even if carbon-based steelmaking is replaced by hydrogen-based steelmaking. After removing impurities from the molten metal, this flux becomes the solid waste product called ‘slag’, a primarily Ca-silicate material. The transformation of slag back into carbonates is thermodynamically spontaneous with negative ΔG in the ambient environment, meaning that ~10% of the CO 2 emissions from iron and steel making could be negated if equipment and methods were developed to support CO 2 mineralization. However, the rate of CO 2 mineralization using slag is slowed by several environmental, geometric, and processing factors. We leverage an experimentally verified model of CO 2 mineralization to determine how to efficiently accelerate the process. Increasing the crystallinity of slag, increasing the relative humidity, and reducing the grain size of slag particles provide the greatest increase in CO 2 mineralization rate at the lowest energy penalty. Increasing the concentration of CO 2 and the temperature provide only modest increases in the CO 2 mineralization rate while incurring a substantial energy penalty. For steelmaking slags, CO 2 mineralization represents low-hanging fruit as the current reuse pathways are low value. For ironmaking slag, replacing the production of amorphous slag for the cement industry with the production of crystalline slag for CO 2 mineralization becomes financially preferable when a carbon price/tax exceeds 67.40 USD/t-CO 2 .

42 ENGINEERING↗
DOE OSTI2012

Synthetic Coal Slag Infiltration into Varying Refractory Materials

The infiltrations of synthetic coal slag into 99%Al{sub 2}O{sub 3}, 85%Al{sub 2}O{sub 3}–15%SiO{sub 2}, and 90%Cr{sub 2}O{sub 3}–10%Al{sub 2}O{sub 3} refractories with a temperature gradient induced along the penetration direction were compared to one another. The infiltrating slag was synthesized with a composition that is representative of an average of the ash contents from U S coal feedstock. Experiments were conducted with a hot-face temperature of 1450°C in a CO/CO{sub 2} atmosphere. Minimal penetration was observed in the 90%Cr{sub 2}O{sub 3}–10%Al{sub 2}O{sub 3} material because interactions between the refractory and the slag produced a protective layer of FeCr{sub 2}O{sub 4}, which impeded slag flow into the bulk of the refractory. After 5 h, the 99%Al{sub 2}O{sub 3} sample exhibited an average penetration of 12.7 mm whereas the 85%Al{sub 2}O{sub 3}–15%SiO{sub 2} sample showed 3.8 mm. Slag infiltrated into the 99%Al{sub 2}O{sub 3} and 85%Al{sub 2}O{sub 3}–15%SiO{sub 2} refractory systems by dissolving the respective refractories' matrix materials, which consist of fine Al{sub 2}O{sub 3} particles and an amorphous alumino-silicate phase. Due to enrichment in SiO{sub 2}, a network-former, infiltration into the 85%Al{sub 2}O{sub 3}–15%SiO{sub 2} system yielded a higher viscosity slag and hence, a shallower penetration depth. The results suggest that slag infiltration can be limited by interactions with the refractory through the formation of either a solid layer that physically impedes fluid flow or a more viscous slag that retards infiltration.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2011

High temperature millimeter wave radiometric and interferometric measurements of slag-refractory interaction for application to coal gasifiers

Millimeter wave (MMW) radiometry can be used for simultaneous measurement of emissivity and temperature of materials under extreme environments (high temperature, pressure, and corrosive environments) such as in slagging coal gasifiers, where sensors have been identified as a key enabling technology need for process optimization. We present a state-of-the-art dual-channel MMW heterodyne radiometer with active interferometric capability that allows simultaneous radiometric measurements of sample temperature, emissivity, and flow dynamics to over 1873 K. Interferometric capability is supplied via a probe signal originating from the 137 GHz radiometer local oscillator (LO). The interferometric 'video' channels allow measurement of additional parameters simultaneously, such as volume expansion, thickness change, and slag viscosity along with temperature or emissivity. This capability has been used to demonstrate measurement of temperature and simulated coal slag infiltration into a chromia refractory brick sample as well as slag flow down a vertically placed refractory brick. Observed phenomena include slag melting and slumping, slag reboil and foam with oxygen evolution, and eventual failure of the alumina crucible through corrosion by the molten slag. These results show the promise of the MMW system for extracting quantitative and qualitative process parameters from operating slagging coal gasifiers, providing valuable information for process efficiency, control, and increased productivity.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2018

Thermodynamics of Boron Removal from Silicon Using CaO-MgO-Al{sub 2}O{sub 3}-SiO{sub 2} Slags

Slag refining is one of few metallurgical methods for removal of boron from silicon. It is important to know the thermodynamic properties of boron in slags to understand the refining process. The relation of the distribution coefficient of boron to the activity of silica, partial pressure of oxygen, and capacity of slags for boron oxide was investigated. The link between these parameters explains why the distribution coefficient of boron does not change much with changing slag composition. In addition, the thermodynamic properties of dilute boron oxide in CaO-MgO-Al{sub 2}O{sub 3}-SiO{sub 2} slags was determined. The ratio of the activity coefficient of boron oxide and silica was found to be the most important parameter for understanding changes in the distribution coefficient of boron for different slags. Finally, the relation between the activity coefficient of boron oxide and slag structure was investigated. It was found that the structure can explain how the distribution coefficient of boron changes depending on slag composition.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Modified DHTT Equipment for Crystallization Studies of Mold Slags

The double hot thermocouple technique (DHTT) enables simulations of the temperature gradient at near-service conditions during continuous casting of steel. With the equipment applied so far, a rectangular slag film of even thickness often cannot be achieved. Further, the minimum temperature frequently lies within the slag film. Modified equipment can avoid these disadvantages via the following design features. The entire furnace chamber is heated to the selected temperature of the cold wire, and the minimum temperature is not located within the slag film. Furthermore, the shape of the heating wire is improved, which enables mounting of a thin, rectangular slag film between four platinum wires. This modification allows for investigations on transparent and translucent slags. So far, the results from DHTT investigations were represented via snapshots of the samples at certain experimental times. Therefore, appropriate methods for the graphical representation of the results were suggested: the maximum crystallinity, the time related to certain crystallinities with a dependence on the position within the slag film, and the crystal growth rate. The CaO-MgO-Al{sub 2}O{sub 3}-SiO{sub 2} slag investigated with this equipment was mineralogically examined additionally, and based on thermodynamic calculations, the allocation of temperatures to certain positions within the crystallized slag film was possible.

36 MATERIALS SCIENCE↗
DOE OSTI2019

The Influence of Sulfur Content on the Carbothermal Reduction of SiMn Slag

This article examines the influence of sulfur content on the carbothermal reduction of MnO and SiO{sub 2} in SiMn slag by carbon black. The sulfur content in the synthetic slag is varied from 0 to 1.0 wt pct. Reduction experiments are carried out in a thermogravimetric (TG) furnace at 1873 K (1600 °C) under CO atmospheric pressure. The reduction rates are measured based on the weight loss data, and the samples are characterized by SEM/EDS and ICP-MS. The wetting property of slag on carbon black is also studied with the sessile drop technique. The reaction rate on the slag-metal interface is one order higher than on the slag-carbon interface. A small amount of sulfur (0.2 and 0.44 wt pct) accelerates the slag-metal reaction rate constant by 2.2 and 4.2 times, respectively. Therefore, small amounts of sulfur in slag significantly improve the reduction of MnO and SiO{sub 2}. The MnS precipitation phenomenon during slag cooling is studied by FactSage simulation and experimental verification.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Effect of Al{sub 2}O{sub 3} Addition on Mineralogical Modification and Crystallization Kinetics of a High Basicity BOF Steel Slag

Basic oxygen furnace (BOF) steel slag is a main byproduct that is produced during the converter steelmaking process. The volume instability and fast crystallization of BOF slag limits its added-value application. This article aims to understand the effect of Al{sub 2}O{sub 3} on the mineralogical modification and crystallization kinetics of a high basicity BOF steel slag. Continuous cooling transformation and time–temperature–transformation curves were constructed to determine the crystallization characteristics of BOF slag. The critical cooling rate to vitrify the slag was experimentally obtained. The crystallization sequence was clarified by integrating in situ and post-mortem observations with thermodynamic calculations. The results suggest that the addition of Al{sub 2}O{sub 3} can effectively remove free lime, decrease the melting point, and improve the glass formation ability of the high basicity BOF slag. Undercooling the slag is enhanced by increasing the cooling rate and/or adding Al{sub 2}O{sub 3}. By steering the addition of Al{sub 2}O{sub 3} and the cooling rate, BOF slag can be modified to obtain a more amorphous phase, presenting an enhanced potential to be a binder for added-value applications.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Novel Approach to Studying Influences of Na{sub 2}O and K{sub 2}O Additions on Viscosity and Thermodynamic Properties of BF Slags

Abstract:: The present work calculated the heat capacity, enthalpy change, and slag temperature of CaO–MgO–Al{sub 2}O{sub 3}–SiO{sub 2} slags after adding Na{sub 2}O or K{sub 2}O, and investigated the influences of Na{sub 2}O and K{sub 2}O on the slag viscosity under given temperatures and heat quantities. It was found that the slag viscosity decreases with the addition of Na{sub 2}O and tends to increase with K{sub 2}O additions at the same temperature. The heat capacity of the slag increases, while the enthalpy change decreases obviously with the increasing addition of Na{sub 2}O or K{sub 2}O. Under the constant heat quantity, an increase in content of Na{sub 2}O or K{sub 2}O of the slag leads to an appreciable increase in slag temperature, whereas the viscosity decreases significantly. Besides, the Na{sub 2}O or K{sub 2}O additions also help to stabilize the slag fluidity and lower energy consumption of blast furnace.

36 MATERIALS SCIENCE↗
DOE OSTI2013

The role of alumina on performance of alkali-activated slag paste exposed to 50 °C

The strength and microstructural evolution of two alkali-activated slags, with distinct alumina content, exposed to 50 °C have been investigated. These two slags are ground-granulated blast furnace slag (containing 13% (wt.) alumina) and phosphorous slag (containing 3% (wt.) alumina). They were hydrated in the presence of a combination of sodium hydroxide and sodium silicate solution at different ratios. The microstructure of the resultant slag pastes was assessed by X-ray diffraction, differential thermogravimetric analysis, and scanning electron microscopy. The results obtained from these techniques reveal the presence of hexagonal hydrates: CAH{sub 10} and C{sub 4}AH{sub 13} in all alkali-activated ground-granulated blast-furnace slag pastes (AAGBS). These hydrates are not observed in pastes formed by alkali-activated ground phosphorous slag (AAGPS). Upon exposure to 50 °C, the aforementioned hydration products of AAGBS pastes convert to C{sub 3}AH{sub 6}, leading to a rapid deterioration in the strength of the paste. In contrast, no strength loss was detected in AAGPS pastes following exposure to 50 °C. -- Highlights: •Strength of alkali-activated slag (AAS) pastes after exposure to 50 °C is studied. •AAS pastes with high alumina content lose strength after the exposure. •C{sub 4}AH{sub 13} and CAH{sub 10} form in these AAS pastes. •Conversion of these calcium alumina hydrates is associated with the strength loss. •AAS pastes with low alumina content maintain its strength after the exposure.

36 MATERIALS SCIENCE↗
DOE OSTI2016

New insights into the hydration of slag in alkaline media using a micro-reactor approach

A micro-reactor approach, developed previously, is used to study the reactions of slag in alkaline media. Micron-sized gaps are milled in slag grains using a focused ion beam (FIB) and subsequently filled with alkaline solutions, leading to dissolution and hydration of the slag. After the hydration is stopped, a scanning electron microscope (SEM) is used to image the gaps. We present the effect of pH and nature of the alkaline solution on the slag dissolution and the hydrate morphology. The results obtained in this study confirm that the presence of aluminum and calcium in solution has a strong retarding effect on the slag dissolution. A major implication of these results is that in blended cements, the reactivity of slag probably suffers from the ions released by cement into solution. We show that strongly adsorbing superplasticizers inhibit the dissolution of slag, but only at lower alkali concentrations and C–S–H seeds may also inhibit the dissolution of slag under certain experimental conditions. The obtained results are compared and contrasted with results obtained for alite and tricalcium silicate previously reported in the literature.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Experimental and Mathematical Simulation Study on the Granulation of a Modified Basic Oxygen Furnace Steel Slag

Basic oxygen furnace (BOF) steel slag is a major waste of the steelmaking industry. Utilization of BOF slag contributes to the sustainability of the steel industry by alleviating its environmental impact. Vitrification during cooling is an effective method to promote the cementitious activity of slags with the aim to apply slags in high value-added applications. In the present study, an Al{sub 2}O{sub 3}- and SiO{sub 2}-modified BOF slag was water granulated at a pilot scale. The amorphous and mineral fractions were measured quantitatively. The critical cooling rate to vitrify the modified slag was calculated through the Time-Temperature-Transformation diagrams constructed using in situ confocal scanning laser microscopy. To provide an insight into the crystallization behavior during the granulation process, a mathematical model was developed. The model was validated by comparing the amorphous fraction obtained from experiments with that from simulation. Temperature profiles of the slag particles with varied sizes were calculated with the aid of COMSOL Multiphysics software. The effect of particle size on the vitrified fraction was discussed in detail and the temperature gradient from surface to center of the particle was identified. The results provide novel fundamental understanding of the vitrification process regarding to the slag valorization, which will help the industrial implementation of granulation for pollution remediation and other engineered environmental systems such as chemical industry and pharmaceutical industry.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Lattice Boltzmann simulation of the dissolution of slag in alkaline solution using real-shape particles

Highlights: • A dissolution numerical model was proposed to capture the real dissolution kinetics of slag in alkaline solution. • The log forward dissolution rate of Si was described as a function of NBO/T and solution pH. • A threshold solid volume fraction of 0.688 was found for a voxel in 3D, 63.8% larger than that for a pixel in 2D. • The proposed dissolution numerical model provides a reliable alternative to study the dissolution kinetics of slag. A dissolution numerical model was proposed in this study to capture the real dissolution kinetics of slag in alkaline solution. It consists of three modules, i.e. (i) simulation of the initial particle parking structure of slag in alkaline solution using real-shape particles of slag, (ii) simulation of the chemical reactions between slag and solution based on the transition state theory, and (iii) simulation of the physical transport of aqueous ions using the lattice Boltzmann method. This dissolution numerical model was verified using experimental results, showing reasonable accuracy. After verification, the dissolution numerical model was implemented to study the influences of temperature and particle shape using a proper recipe of slag in alkaline solution. This recipe was designed to avoid solid phase precipitation or gel formation via thermodynamic analysis. The simulation results showed faster dissolution kinetics of slag when using higher temperatures and more irregular particle shapes.

36 MATERIALS SCIENCE↗