Blast furnace injection for minimizing the coke rate and CO2 emissions

The results of the analysis of production data on the operation of blast furnace No. 1 (useful volume 1007 m3) of Ural Steel JSC for the period from 2013 to 2018 are presented. During this period, pellets from the Mikhailovsky GOK were used with varying degrees of fluxing: pellets of natural basicity in the ratio of CaO/SiO2 equal to 0.08 ± 0.02 units. (2013-2015) and partially fluxed pellets with a basicity of 0.52 ± 0.05 units. (from 2016 to the present). It has been established that the effectiveness of the use of pellets of various basicities is determined by their behavior in the blast furnace and depends on the proportion of pellets in the iron ore part of the charge. The gas-dynamic conditions of the smelting worsen with an increase in the proportion of pellets in the charge, which is accompanied by an increase in the specific pressure drop and forces the flow rate to be adjusted. There is an optimal level of specific pressure drop (53–55 Pa per 1 m3 of blast per minute) for the operating conditions of blast furnace No. 1 of Ural Steel, which ensures the optimum combination of the melting characteristics. Deviation from the optimal level of pressure drop leads to an increase in coke rate and a decrease in the degree of CO use, which is associated with gas distribution disturbance. Due to the increase in high-temperature properties, the replacement of non-fluxed pellets with off-fluxed pellets improves the gas-dynamic conditions in the lower part of the mine (in the cohesive zone). This leads to a decrease in the total pressure drop and specific pressure drop at a constant flow rate of the blast, and is a reserve for melting intensification. To minimize coke rate and maintain the high-performance operation of blast furnaces of Ural Steel JSC, it is necessary to work on 40–45 % of fluxed or 20–25 % acid pellets in a charge. An increase in pellet consumption while maintaining the efficiency of blast-furnace smelting is possible only if their high-temperature properties are improved. The improvement of these properties is possible as a result of optimizing the basicity and increasing the MgO content, which affects the structure and properties of the silicate bond. This work is carried out within a framework of the government order (No. FZRU-2020-0011) of the Ministry of Science and Higher Education of the Russian Federation.

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Reducing Net CO2 Emissions Using Charcoal as a Blast Furnace Tuyere Injectant

ISIJ International ◽

10.2355/isijinternational.52.1489 ◽

2012 ◽

Vol 52 (8) ◽

pp. 1489-1496 ◽

Cited By ~ 36

Author(s):

John G. Mathieson ◽

Harold Rogers ◽

Michael A. Somerville ◽

Sharif Jahanshahi

Keyword(s):

Blast Furnace ◽

Co2 Emissions ◽

Blast Furnace Tuyere

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Pathways for Low-Carbon Transition of the Steel Industry—A Swedish Case Study

Energies ◽

10.3390/en13153840 ◽

2020 ◽

Vol 13 (15) ◽

pp. 3840

Author(s):

Alla Toktarova ◽

Ida Karlsson ◽

Johan Rootzén ◽

Lisa Göransson ◽

Mikael Odenberger ◽

...

Keyword(s):

Blast Furnace ◽

Co2 Emissions ◽

Steel Industry ◽

Carbon Capture ◽

Direct Reduction ◽

Carbon Capture And Storage ◽

Steel Production ◽

Mitigation Measures ◽

Production Plant ◽

Low Carbon

The concept of techno-economic pathways is used to investigate the potential implementation of CO2 abatement measures over time towards zero-emission steelmaking in Sweden. The following mitigation measures are investigated and combined in three pathways: top gas recycling blast furnace (TGRBF); carbon capture and storage (CCS); substitution of pulverized coal injection (PCI) with biomass; hydrogen direct reduction of iron ore (H-DR); and electric arc furnace (EAF), where fossil fuels are replaced with biomass. The results show that CCS in combination with biomass substitution in the blast furnace and a replacement primary steel production plant with EAF with biomass (Pathway 1) yield CO2 emission reductions of 83% in 2045 compared to CO2 emissions with current steel process configurations. Electrification of the primary steel production in terms of H-DR/EAF process (Pathway 2), could result in almost fossil-free steel production, and Sweden could achieve a 10% reduction in total CO2 emissions. Finally, (Pathway 3) we show that increased production of hot briquetted iron pellets (HBI), could lead to decarbonization of the steel industry outside Sweden, assuming that the exported HBI will be converted via EAF and the receiving country has a decarbonized power sector.

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CO2 Utilization in the Ironmaking and Steelmaking Process

Metals ◽

10.3390/met9030273 ◽

2019 ◽

Vol 9 (3) ◽

pp. 273 ◽

Cited By ~ 4

Author(s):

Kai Dong ◽

Xueliang Wang

Keyword(s):

Stainless Steel ◽

Blast Furnace ◽

Continuous Casting ◽

Co2 Emissions ◽

Ferrous Metallurgy ◽

Large Scale ◽

Metallurgical Industry ◽

Co2 Utilization ◽

Bottom Blowing ◽

Metallurgy Process

Study on the resource utilization of CO2 is important for the reduction of CO2 emissions to cope with global warming and bring a beneficial metallurgical effect. In this paper, research on CO2 utilization in the sintering, blast furnace, converter, secondary refining, continuous casting, and smelting processes of stainless steel in recent years in China is carried out. Based on the foreign and domestic research and application status, the feasibility and metallurgical effects of CO2 utilization in the ferrous metallurgy process are analyzed. New techniques are shown, such as (1) flue gas circulating sintering, (2) blowing CO2 through a blast furnace tuyere and using CO2 as a pulverized coal carrier gas, (3) top and bottom blowing of CO2 in the converter, (4) ladle furnace and electric arc furnace bottom blowing of CO2, (5) CO2 as a continuous casting shielding gas, (6) CO2 for stainless steel smelting, and (7) CO2 circulation combustion. The prospects of CO2 application in the ferrous metallurgy process are widespread, and the quantity of CO2 utilization is expected to be more than 100 kg per ton of steel, although the large-scale industrial utilization of CO2 emissions is just beginning. It will facilitate the progress of metallurgical technology effectively and promote the energy conservation of the metallurgical industry strongly.

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