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dolomite dissolution in slag

Dec 09, 2012· Here we show, using a dissolution experiment, that dried dolomite-rich CCA have 6–10 times lower rates of dissolution than predominantly Mg …

after acid dissolution with 1 mol/L HNO 3 by inductively coupled plasma optical emission spectroscopy (ICP-OES, Perkin Elmar 7000) in triplicate, are also shown in Table 1. The Ca to Mg molar ratio of the dolomite is 1.07. For calcination, approximately 50 g of raw dolomite was placed

Through thermal simulation experiment and SEM analysis, limestone dissolution in a steelmaking slag was studied. The results showed that the dissolution rate of limestone is 5.4 times greater than lime under the same conditions in slag, the dissolution rate of limestone in slag increases rapidly with the increase of stirring gas flux. The rapid dissolution of limestone in the slag can be ...

Nov 01, 2000· In this study, the solubility of a high purity dolomite was measured directly by monitoring dissolution in Ca−Mg−HCO 3 /CO 3 solutions designed to bracket the presumed solubility product of dolomite, pK s dolomite [= −log (Ca 2+)(Mg 2+)(CO 2− 3) 2, where the values in parentheses are activities at equilibrium], between 16.0 and 19.0, at ...

Aug 26, 2003· Slag is a ubiquitous byproduct of the iron- and steel-refining industries. In northwestern Indiana and northeastern Illinois, slag has been deposited over more than 52 km2 of land surface. Despite the widespread use of slag for fill and construction purposes, little is known about its chemical effects on the environment. Two slag-disposal sites were examined in northwestern Indiana where slag ...

Lime dissolution in stagnant slag was studied first and dissolution of lime, limestone and dolomite under forced convection were carried out by new experimental setup. Dissolution of different CaO samples into stagnant converter slags was carried out in a closed tube furnace at 1873K. In the case of CaO-'FeO'-SiO2 slag, the dissolution of ...

Lime dissolution in stagnant slag was studied first and dissolution of lime, limestone and dolomite under forced convection were carried out by new experimental setup. Dissolution of different CaO samples into stagnant converter slags was carried out in a closed tube furnace at 1873K.

The dissolution of lime and dolomite into different slag systems has been the topic of many researchers [1]-[9]. Russell [1] studied lime reactivity as well as dissolution rates and reported that the dissolution of lime could be determined at room temperature by ASTM water reactivity test.

Nov 08, 2018· These observations suggest that dolomite and palygorskite formed sequentially, and support a model by which the release of Mg 2+ ions and the buffering of solution pH during dolomite dissolution promote the formation of palygorskite. This new diagenetic model explains the co-occurrence of palygorskite and dolomite in the rock record, and ...

These observations suggest that dolomite and palygorskite formed sequentially, and support a model by which the release of Mg 2+ ions and the buffering of solution pH during dolomite dissolution promote the formation of palygorskite. This new diagenetic model explains the co-occurrence of palygorskite and dolomite in the rock record, and ...

The kinetics of dolime dissolution containing 20 and 50 pct of magnesium oxide in steelmaking slags has been studied in a high-temperature experiment. The dissolution tests were carried out under static conditions at temperatures of between 1573 K and 1873 K (1300 °C to 1600 °C). Cylindrical samples of dolime were introduced into pre-melted slag at predetermined time intervals.

When the CaO and MgO content is combined, the slag viscosity can be influenced positively. The high reactivity of the soft-burnt material provides for a rapid dissolution of the dolomite grain in the slag. Top-blown oxygen converters • Limit the refractory wear in the slag zone thus extending markedly the furnace campaigns

dissolution of dolomite is a (slow) reaction rate limited process at room temperature [Lund et al., 1973]. The main aim of the current experimental research is to understand the evolution of hydraulic conductivity and flow patterns, caused by concurrent dissolution of dolomite and precipi-tation of calcium carbonate, in porous dolomite rocks. In

Dolomite by means of a quantitative laboratory investigation. The rates of dissolution of selected samples of Lirio Limestone and Isla de Mona Dolomite were measured in CO2-saturated water. These results then can be compared with other investi-gations of calcite and dolomite dissolution.

is influenced strongly by temperature and slag composition. Mechanisms of lime dissolution into slag under different conditions have been studied previously.1–9) Umakoshi et al.,2) studied the dissolution of a rotating burnt dolomite cylinder in Fe t O–CaO–SiO 2 slag as a func-tion of temperature (1350–1400°C) and rotational speed.

burnt dolomite in slag A. dissolution rate of Research Article (534) Transactions ISIJ, Vol. 24, 1984 ship between the decrease in radius and the immer-sion time is approximately linear though the linearity is worse than that for the dissolution of sintered CaO5 or MgO.6) The dissolution rates, …

Study On Lime Dissolution In Converter Slag. importance of lime dissolution in converter slagast lime dissolution in slag would ensure the power of the slag for dephosphorisation, shorten the process and reduce the consumption of the raw material as well as energy the dissolution of lime and dolomite into different slag systems has been the topic of many researchers 1-9ussell.

Elucidating dissolution kinetics and mechanisms at carbonate mineral-water interfaces is essential to many environmental and geochemical processes, including geologic CO(2) sequestration in deep aquifers. In the present work, effects of background electrolytes on dolomite (CaMg(CO(3))(2)) reactivity …

Limestone and dolomite decompose at 800-900ºC, through an endothermic reaction releasing CO 2 and CaO and MgO that react and form part of the melt. However, it is known that limestone and CaO are poorly wetted by the primary melt. The use of Calumite Slag provides between 15% and 40% of the CaO in the new glass from the batch.

In this work, the influence of a dolomite filler, in combination with pulverized fly ash, on the sulfuric acid (H 2 SO 4) resistance of alkali-activated slag (AAS) is studied.The evolution of compressive strength and mass loss, as well as mineralogical, compositional, and molecular structural alteration of hardened AAS binders containing 0%, 20%, and 40% dolomite filler, or a combination of 20 ...

Kinetics of Flux Dissolution in Oxygen Steelmaking. Neslihan Dogan. Related Papers. Steelmaking and Refining Volume AISE 1998. By stefani zahro. FUNDAMENTALS OF EAF AND LADLE SLAGS AND LADLE REFINING PRINCIPLES. By Sanup Panda. Analysis …

dissolution. The addition of crushed dolomite rock reduced the pH very slowly through the dissolution of quartz grains within the crushed rock. The MicroTox™ toxicity was reduced ... The leachate discharging from the slag fill is adversely affecting the water quality of many of the wetlands in the Calumet region. The slag contains lime and ...

Calcite dissolution Dolomite dissolution Lower Devonian Cite this article as: Rowberry M, Dubois C, Kaufmann O, Baele J-M, Blahůt J: Weathering by dolomite dissolution responsible for the formation of an important palaeotological locality in the Prague Synform.. Acta Geodyn. Geomater., 15, No. 3 (191), 297–309, 2018. DOI: 10.13168/AGG.2018.0022

17 the resistance of ground granulated blastfurnace slag (GGBS) activated with calcined 18 dolomite, as a novel alkali activator, to 5% sodium sulfate attack and 5% magnesium 19 sulfate attack. Two calcined dolomites, D800 and D1000, were prepared in the 20 laboratory at 800 °C and 1000 °C respectively.

•Insertion of dolomite-based samples of varying composition and calcination condition •Isothermal reaction duration fixed to 10 min •Disc sample not extracted at the end of dissolution test •Quenching of crucible, slag and immersed sample in liquid nitrogen Experimental setting High-temperature static dissolution investigation EAF slag ...

The 'microbial dolomite model' proposed in recent years provides new insight into the study of dolomite genesis. However, the lack of research on the precipitation rate makes it difficult to judge whether the microbial dolomite can be deposited as a thick dolomite formation alone.

Nov 01, 2015· To reduce refractory damage during steelmaking, precise control of slag composition is important. Usually, the formation and decomposition rates of interfacial layer are considered to be rate‐controlling steps. The influence of the interfacial layer on the dissolution rate was investigated. The reagents were mixed and sintered to make an oxide that simulated the interfacial layer. The sample ...

May 18, 2010· Dissolution of different CaO samples into molten synthetic 'FeO'-SiO 2 and 'FeO'-SiO 2-CaO slags was carried out in a closed tube furnace at 1873 K.The slag was kept stagnant. It was found that the dissolution rate was very fast when CaO rod was dipped into 'FeO'-SiO 2 slag. In the case of 'FeO'-SiO 2-CaO slag, the dissolution of CaO rod in the stagnant slag was retarded after ...

Oct 01, 2019· A ground granulated blast-furnace slag (SG), pulverized fly ash (PFA), and dolomite fines (DM), with the oxide composition, mineralogical and particle size analysis shown in Table 1, Fig. 1, and Fig. 2, were used as the binder.Both SG and PFA contain mainly vitreous phases enriched in calcium, aluminum, silicon, as well as trace amounts of crystalline phases (e.g., mullite, calcite, quartz).

Aug 01, 2015· The most important mechanism is the dissolution of lining into the slag. Rapid slag formation in order to bind and neutralize acidic SiO2 forming in the blow beginning, is a key point. Highly oxidizing hot slag dissolves magnesia or dolomite lining readily. Use of calcined dolomite can greatly improve the lining life.

After the development of experimental setup, lime, limestone and dolomite dissolution in slag were carried out by using the new experimental equipment. Both dissolution mechanism and dissolution rate of slag additives in slag were studied. The decomposition mechanism of limestone and dolomite is also given in present work. ...

Jul 13, 2018· On the basis of the mode of formation, dolomites can broadly be divided into two groups: primary dolomite and secondary dolomite. 2 Primary dolomite precipitate directly from aqueous solution, mostly at or near room temperature (20-35 o C), with no CaCO 3 dissolution involved. 3 However, dolomite can also form as a secondary phase replacing the precursor mineral calcite …

2.2. Dissolution Mechanism of Dolomite MgO has a tendency to form a solid product with FeO in steelmaking slags with a low melting point.10) When dolomite dissolves in slag, slag penetrates to the dolomite through the pores of the dolomite particles. CaO and MgO diffuse out of the dolomite due to the concentration differ-ence.

burnt dolomite in slag A. dissolution rate of Research Article (534) Transactions ISIJ, Vol. 24, 1984 ship between the decrease in radius and the immer-sion time is approximately linear though the linearity is worse than that for the dissolution of sintered CaO5 or MgO.6) The dissolution rates, …

In the present study, the dissolution mechanism and rate of lime, limestone and dolomite in converter slag was studied. Lime dissolution in stagnant slag was studied first and dissolution of lime, limestone and dolomite under forced convection were carried out by new experimental setup.Dissolution of different CaO samples into stagnant converter slags was carried out in a closed tube furnace ...

Apr 16, 2021· Magnesia dolomite brick has good thermal shock stability, good resistance to structural peeling and resistance. The permeability of molten slag also has the unique performance of purifying molten steel. 1. Slag resistance. Magnesia dolomite bricks have a large dissolution loss in the initial slag, and less erosion in the later slag.

Mar 29, 2019· 10%· The authors reported that the dissolution rate of sintered MgO is highly influenced by the slag composition and is much higher in the slag system of MgO-SiO 2-B 2 O 3 compared to FeO-CaO-SiO 2 slag. According to Satyoko and Lee,[ 18 ] who studied doloma and dolomite dissolution in BOF slag, the formation of magnesiowustite weakened the 2CaO ...

The rate of dissolution and mechanisms of dissolution of dolomite and magnesite were examined in the study. The major conclusions are as follows: For dolomite, it appears that the CaO is dissolved away first and the MgO grains enter the slag where they …

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