Energy efficiency characterization and optimization of mechanical stirring multiphase dispersion processes: Applied to Kanbara reactors for hot metal desulfurization

Li, Qiang; Ma, Suwei; Feng, Mingxia; Li, Hong; Zong-shu, Zou

doi:10.1016/j.jmrt.2023.04.137

Cited by 3 publications

(2 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With the mass transfer theory, the mass transfer rate of oxygen in the gas phase and the sulfur mass transfer process in the slag phase can be represented by Equation ( 4) and Equation ( 5), respectively. Since the interface reaction rate is very fast, it can be considered that 2 O i P ≈ 0 and Si C ≈ 0; under this condition, Equations ( 4) and ( 5) are simplified to (6) and (7), respectively. Given that the reaction occurs at high temperatures and under conditions of heterogeneous nucleation, the interfacial reaction and SO 2 escaping into the gas phase via the liquid-gas interface process are not the rate-limiting steps.…”

Section: Removal Rate Of Sulfur From Slagmentioning

confidence: 99%

“…A large amount of solid waste, such as pulverized blast furnace slag, desulfurized slag, and steel slag, is produced in the process of desulfurization and converter steelmaking. The Kanbara Reactor (KR) desulfurization process is widely used in various steel plants as an efficient pre-desulfurization process before the converter process [1][2][3][4][5][6][7]. In the KR desulfurization process, an impeller lined with refractory material is submerged in the ladle, where it rotates and stirs the hot metal to create a vortex.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of Flow Rate and Partial Pressure of Oxygen on Desulfurization of KR Slag

Jiang,

Muvunyi

et al. 2024

Metals

View full text Add to dashboard Cite

KR (Kanbara Reaction) desulfurization slag is a solid waste that is not sufficiently utilized. This is because the KR desulfurization slag contains 1–2.5% sulfur, which is directly used in steel smelting to increase the sulfur content in molten steel. Therefore, the possibility of oxidation desulfurization of KR desulfurization slag was studied in this study. Experiments were conducted to investigate the possibility of removing sulfur from used KR (Kambara Reaction) slag with oxidation. The KR slag samples were treated with oxidative desulfurization in the oxygen partial pressure range of 0.05 bar–1.00 bar, with a gas flow rate ranging from 2 L min−1 to 6 L min−1, and at a temperature of 1420 °C. X-ray diffraction (XRD), an infrared carbon sulfur analyzer, and scanning electron microscopy–energy dispersive X-ray spectrometry (SEM–EDS) analysis were used to reveal the oxidative desulfurization mechanism of KR desulfurization slag. At low oxygen pressure (PO2 < 0.20 bar), the desulfurization rate of slag oxidized for 120 min increased with the increase in oxygen partial pressure. At high oxygen pressure (PO2 ≥ 0.20 bar), the desulfurization rate of slag samples did not change with the change in oxygen partial pressure, and the desulfurization rate was higher than 93.5%. At low oxygen pressure (PO2 < 0.20 bar), the residual sulfur in the slag after oxidation still existed in the slag as the CaS phase. At high oxygen pressure (PO2 ≥ 0.20 bar), the residual sulfur in the slag oxidized from the CaS phase to the 11CaO·7Al2O3·CaS phase in the slag. The sulfur removal rate was directly correlated with the slag surface area and the flow rate of the reaction gas, and it increased with an increase in both surface area and gas flow rate.

show abstract

Section: Removal Rate Of Sulfur From Slagmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Effect of Flow Rate and Partial Pressure of Oxygen on Desulfurization of KR Slag

Jiang,

Muvunyi

et al. 2024

Metals

View full text Add to dashboard Cite

show abstract

Large-scale dispersed phase-resolved direct numerical simulation (LDPR-DNS) of mechanically stirred reactors: Understanding the dispersion mechanism of multiphase flow and qualifying the droplets produced

Ma,

Li,

Peng

et al. 2024

Powder Technology

View full text Add to dashboard Cite

Effects of Different CaO/Al2O3 Ratios on the Phase Composition and Desulfurization Ability of CaO-Based Desulfurizers in Hot Metal

Shen,

Lin,

Chang

et al. 2024

Metals

View full text Add to dashboard Cite

In response to the development of low-carbon smelting technology, reducing the use of fluor-containing materials in desulfurizers is an important research topic. The development of new-generation KR (Kambara Reactor) desulfurizers is shifting towards a higher Al2O3 content rather than CaF2, yet there is currently an absence of thorough and comprehensive mechanisms for desulfurization. Consequently, this research provides an extensive comparison using a specially constructed small-scale KR desulfurization hot model test, alongside FactSage simulation and SEM analysis (of desulfurization process). The findings indicate that at 1400 °C, for the desulfurization of molten iron, the capacity for desulfurization initially increases and then diminishes as the Al2O3 content in the KR desulfurizer rises. With Al2O3 content in the desulfurizer below 22 wt.%, the phase composition predominantly consists of C3A, employing a solid(slag)–liquid(metal) diffusion method for desulfurization. The optimal desulfurization capacity (Ls: 64.1) is observed when the Al2O3 content is 15 wt.%, attributed to the simultaneous presence of CaO particle precipitation and C3A. However, as the Al2O3 content reaches 20 wt.%, all the oversaturated CaO integrates into C3A, leading to a reduction in Ls from 64.1 to 10.7, thereby diminishing the desulfurization capacity by approximately sixfold. When Al2O3 exceeds 22 wt.%, the phase composition transitions from the C3A to C12A7 phase, and the desulfurization approach shifts from solid(slag)–liquid(metal) to liquid(slag)–liquid(metal) diffusion, with Ls decreasing to 23.4. This reduction is due to C12A7’s lower sulfur capacity compared to C3A and the absence of saturated CaO particle precipitation. Therefore, for Al2O3 to effectively replace fluorite in KR desulfurizers, a higher presence of C3A phases and CaO particle precipitation are essential. The desulfurizer must contain over 65 wt.% CaO and maintain Al2O3 levels at 10~16.2 wt.%.

show abstract

Energy efficiency characterization and optimization of mechanical stirring multiphase dispersion processes: Applied to Kanbara reactors for hot metal desulfurization

Cited by 3 publications

References 55 publications

Effect of Flow Rate and Partial Pressure of Oxygen on Desulfurization of KR Slag

Effect of Flow Rate and Partial Pressure of Oxygen on Desulfurization of KR Slag

Large-scale dispersed phase-resolved direct numerical simulation (LDPR-DNS) of mechanically stirred reactors: Understanding the dispersion mechanism of multiphase flow and qualifying the droplets produced

Effects of Different CaO/Al2O3 Ratios on the Phase Composition and Desulfurization Ability of CaO-Based Desulfurizers in Hot Metal

Contact Info

Product

Resources

About