ORALS

SESSION: IronWedPM2-R2	Assis International Symposium (9th Intl. Symp. on Advanced Sustainable Iron & Steel Making)
Wed. 29 Nov. 2023 / Room: Dreams 2
Session Chairs: Paulo Assis; Session Monitor: TBA

16:25: [IronWedPM210] OS
A NUMERICAL STUDY OF SCENARIOS FOR THE SUBSTITUTION OF PULVERIZED COAL INJECTION BY BLAST FURNACE GAS ENRICHED BY HYDROGEN AND OXYGEN
Jose Adilson De Castro¹ ; Giulio Antunes De Medeiros² ; Marcos De Campos³ ; Leonardo Martins Da Silva⁴ ; ¹UFF - Federal Fluminense University, Volta Redonda, Brazil; ²UFF-Programa de Pos Graduação em Engenharia Metalurgica, Volta Redonda, Brazil; ³UFF - Federal Fluminense U., Volta Redonda, Brazil; ⁴Universidade Federal Fluminense, Volta Redonda, Brazil;
Paper Id: 69 [Abstract]

A numerical simulation procedure is proposed for analyzing the partial replacement of pulverized coal injection by hydrogen, oxygen, and blast furnace gas (BFG) injections mixed with pulverized coal (PCI) within the tuyeres of large blast furnaces. The massive use of hydrogen-rich gas is highly attractive to the steelmaking blast furnace in the context of carbon net-zero hot metal production. Likewise, this new approach allows for increasing productivity and decreasing the specific emissions of carbon dioxide toward a net-zero carbon ironmaking technology. Nevertheless, pulverized coal injection gas mixture is a complex technology, in addition to the impact on chemical reactions and energy exchange, the internal temperature and gas flow pattern can also change drastically. With a view to assessing the state of the furnace in this complex operation, a comprehensive mathematical model using the multiphase theory was developed. The model simultaneously handles bulk solids (sinter, small coke, pellets, granular coke, and iron ore), gas, liquid metal and slag, and coal powder phases. The associated conservation equations are formulated for momentum, mass, chemical species, and energy while being discretized and solved using finite volume techniques. The numerical model was validated against the reference operating conditions using 220 kilograms per ton of pig iron (kg/tHM) of pulverized coal. Therefore, the combined injection of different concentrations of fuel hydrogen, blast furnace gas, and oxygen was simulated for replacing 40, 60 and 80 kg/tHM of coal injection. Theoretical analysis showed that the best scenario with stable operation conditions could be achieved with a productivity increase of 20% corresponding to a CO2 reduction of 15% and 60 kg/tHM of PCI replacement

References:
[1] Castro, J.A.; Takano, C.; Yagi, J. A theoretical study using the multiphase numerical simulation technique for effective use of H2 as blast furnaces fuel. J. Mater Res Technol., 2017, 6, 258-270. [2] Adilson de Castro, J.; Medeiros, G.A.d.; Oliveira, E.M.d.; de Campos, M.F.; Nogami, H. The Mini Blast Furnace Process: An Efficient Reactor for Green Pig Iron Production Using Charcoal and Hydrogen-Rich Gas: A Study of Cases. Metals 2020, 10, 1501. https://doi.org/10.3390/met10111501 [3] Castro, J.A. A Multi-Dimensional Transient Mathematical Model of Blast Furnace Based on Multi-Fluid Model. Doctor Thesis, Ph.D.-Tohoku University, Sendai, Japan, 2001. [4] Castro, J.A.; Araujo G.M.; Mota I.O.; Sasaki Y.; Yagi J. Analysis of the combined injection of pulverized coal and charcoal into large blast furnaces. J Mater Res Technol., 2013, 2, 308-314.

SESSION: IronThuAM-R2	Assis International Symposium (9th Intl. Symp. on Advanced Sustainable Iron & Steel Making)
Thu. 30 Nov. 2023 / Room: Dreams 2
Session Chairs: Wilson Ferreira Santos Jr.; Session Monitor: TBA

12:00: [IronThuAM02] OS
ANALYSIS OF THE HYDROGEN GAS AS FUEL FOR LARGE BLAST FURNACES USING A COMPREHENSIVE MULTIPHASE NUMERICAL SIMULATION APPROACH
Jose Adilson De Castro¹ ; Giulio Antunes De Medeiros² ; Elizabeth Oliveira³ ; ¹UFF - Federal Fluminense University, Volta Redonda, Brazil; ²UFF-Programa de Pos Graduação em Engenharia Metalurgica, Volta Redonda, Brazil; ³Center for Technological Education Celso Suckow da Fonseca, Valenca, Brazil;
Paper Id: 68 [Abstract]

A numerical simulation procedure is proposed for analyzing hydrogen, oxygen, and blast furnace gas (BFG) injections mixed with pulverized coal within the tuyeres of large blast furnaces. The massive use of hydrogen-rich gas is highly attractive to the steelmaking blast furnace in the context of carbon net-zero hot metal production. Likewise, this new approach allows for increasing productivity and decreasing the specific emissions of carbon dioxide toward a net-zero carbon ironmaking technology. Nevertheless, mixed gas with pulverized coal injections is a complex technology with drastic changes in the inner temperature and gas flow patterns, beyond their effects on the chemical reactions and energy exchanges. Focusing on the evaluation of inner furnace status under such complex operation a comprehensive mathematical model has been developed using the multi-interactions of phases theory. The model treats simultaneously the lump solids (sinter, small coke, pellets, granular coke, and iron ores), gas, liquids metal and slag, and pulverized coal phases. The governing conservation equations are formulated for momentum, mass, chemical species, and energy simultaneously discretized and solved using the finite volume technique. The numerical model is verified against a reference operational condition using pulverized coal of 195 kilograms per ton of hot metal (kg/thm). Thus, combined injections of varying fuel hydrogen, BFG, and oxygen concentrations are simulated for 180 and 220 kg/thm of coal injection. Theoretical analysis showed that stable operations conditions could be achieved with a productivity increase of 53%. Finally, we demonstrated that the net carbon utilization per hot metal ton decreased to 15%.

References:
[1] Castro JA, Takano C, Yagi J. A theoretical study using the multiphase numerical simulation technique for effective use of H2 as blast furnaces fuel. J. Mater Res Technol 2017; 6:258-270. [2] de Castro JA, de Medeiros GA, de Oliveira EM. A Comprehensive Modeling as a Tool for Developing New Mini Blast Furnace Technologies Based on Biomass and Hydrogen Operation. J. Sustain. Metall. 2020; 6:281-293. [3] de Castro JA, de Medeiros GA, de Oliveira EM, de Campos MF, Nogami H. The Mini Blast Furnace Process: An Efficient Reactor for Green Pig Iron Production Using Charcoal and Hydrogen-Rich Gas: A Study of Cases. Metals. 2020; 10(11): 1501-1522.

SESSION: IronThuAM-R2	Assis International Symposium (9th Intl. Symp. on Advanced Sustainable Iron & Steel Making)
Thu. 30 Nov. 2023 / Room: Dreams 2
Session Chairs: Wilson Ferreira Santos Jr.; Session Monitor: TBA

12:50: [IronThuAM04] OS
ANALYSIS OF THE PERFORMANCE OF SHAFT FURNACES WITH PARTIAL REPLACEMENT OF THE BURDEN WITH SELF-REDUCING PELLETS CONTAINING BIOMASS
Jose Adilson De Castro¹ ; Giulio Antunes De Medeiros² ; ¹UFF - Federal Fluminense University, Volta Redonda, Brazil; ²UFF-Programa de Pos Graduação em Engenharia Metalurgica, Volta Redonda, Brazil;
Paper Id: 70 [Abstract]

The shaft furnace known Midrex is used for the production of direct reduced iron with the use of reformed gas. Another process based on shaft reactors is the Tecnored process, which exhibits the great advantage of using self-reducing agglomerates. Therefore, it was proposed a combination of the shaft furnace for direct reduction with self-reducing pellet burden. In addition, with the aim of improving the furnace efficiency and reducing the need for reformed gas, the injection of natural gas and oxygen into the bustle region is proposed. Thus, it is possible to exploit the advantages of direct reduction involving high amounts of hydrogen and faster reactions of the self-reducing process to decrease the CO2 emission, compared to that of blast furnace. The energy profile, productivity, and carbon emission of the traditional shaft furnace were compared with the simulated results after partial replacement of the burden with self-reducing pellets containing fines of elephant grass charcoal. The simulation results for a combination of 15% of self-reducing pellets in the burden with 3.5% oxygen and natural gas injections were the best among the scenarios simulated, with the productivity being 2.9 ton/m3/day and the decrease in the amount of reformed gas being 18%.

References:
[1] Castro JA, Rocha EP, Oliveira EM, Campos MF, Francisco AS. Mathematical modeling of the shaft furnace process for producing DRI based on the multiphase theory. REM - International Engineering Journal. 2018;71(1):81-87

SESSION: MineralWedPM1-R7	Torem International Symposium (8th Intl. Symp. on Sustainable Mineral Processing)
Wed. 29 Nov. 2023 / Room: Sunflower
Session Chairs: Fernando Jose Gomes; Session Monitor: TBA

14:55: [MineralWedPM107] OS
ANALYSIS OF SUSTAINABLE IRON ORE SINTERING PROCESS USING MODELING APPROACH
Jose Adilson De Castro¹ ; Marcos De Campos² ; Elizabeth Oliveira³ ; Giulio Antunes De Medeiros⁴ ; Leonardo Martins Da Silva⁵ ; ¹UFF - Federal Fluminense University, Volta Redonda, Brazil; ²UFF - Federal Fluminense U., Volta Redonda, Brazil; ³Center for Technological Education Celso Suckow da Fonseca, Valenca, Brazil; ⁴UFF-Programa de Pos Graduação em Engenharia Metalurgica, Volta Redonda, Brazil; ⁵Universidade Federal Fluminense, Volta Redonda, Brazil;
Paper Id: 71 [Abstract]

The decreasing of CO2 emissions on the ironmaking industries is a challenging issue. The massive use of granulated biomass and biogas in the iron ore sintering process are promising technological solutions to mitigate the environmental impacts on the steel plant. We focused on the development of a computational tool to analyze and suggest new practices for the sintering process using an integrated modeling approach by applying the multiphase and multicomponent theory. New phases, chemical species and rate equations are included. The model predictions were confronted with industrial data showing good adherence. New scenarios for utilizing the combined technologies of granulated biomass and biogas injection are investigated. The model predictions indicated that the high performance of the process with suitable sinter quality could be achieved. The sintering process fully operating with renewable energy sources is demonstrated.

References:
[1] J. A. Castro, E. M. Oliveira, M. F. Campos, C. Takano and J. Yagi: Journal of Cleaner Production 198(2018), 654. https://doi.org/10.1016/j.jclepro.2018.07.082 [2] J. A. Castro, N. Nath, A. B. França, V. S. Guilherme and Y. Sasaki: Ironmaking & Steelmaking 39(2012), 605. [3] J. A. Castro, C. J. L. Pereira, V. S. Guilherme, E. P. Rocha and A. B. França: J. Mater Res Technol, 2 (2013), 323. http://dx.doi.org/10.1016/j.jmrt.2013.06.002.