Blast Furnace Injection Research Articles

Comparative Study on Coke Oven Gas and Refined Hydrogen-Rich Gas Injection in Blast Furnace: Effects on Tuyere and Raceway Behavior

Comparative Study on Coke Oven Gas and Refined Hydrogen-Rich Gas Injection in Blast Furnace: Effects on Tuyere and Raceway Behavior

Pulverization of municipal solid waste and utilization of pulverized product as alternative fuel for blast furnace injection

Pulverization of municipal solid waste and utilization of pulverized product as alternative fuel for blast furnace injection

Catalytic hydrothermal reaction of biomass and its application in blast furnace injection: Physicochemical, conversion mechanism, combustion behavior

This study employs a combination of experimental research and computational fluid dynamics (CFD) simulation to evaluate the optimal conditions for catalytic hydrothermal carbonization suitable for blast furnace injection. Through FTIR spectroscopy, Raman spectroscopy, ICP analysis, and combustion kinetics analysis, the physical and chemical properties of the hydrochar were determined. Subsequently, these properties along with kinetic parameters were applied to an improved CFD model to compare the flow patterns and combustion performance of hydrochar with PCI coal in blast furnaces. The results indicate that the optimal HTC conditions are identified at 300 °C with FeCl3 catalysis, yielding hydrochar (HTC-300-FeCl3) characterized by a calorific value of 32.10 MJ/kg, 98 % K element removal, and enhanced carbonaceous structure ordering. This is attributed to the addition of FeCl3 effectively enhances the generation of hydroxyl radicals in the aqueous phase and promotes deoxygenation and hydrogenation reactions in the solid phase, improving the quality of hydrochars. In addition, CFD model shows that the HTC-300 FeCl3 exhibits a higher burnout (86.2 %) and average gas temperature (2383.1 K) compared to PCI coal, indicating its greater potential as a PCI coal substitute in BF injection.

When is the right time to invest in hydrogen metallurgy projects for iron and steel enterprises?

Hydrogen metallurgy technology is considered a key technology for the iron and steel industry to achieve carbon neutrality. However, it has been slow to be widely promoted in China due to factors such as stranded costs from carbon metallurgy equipment, hydrogen production costs, consumer preferences, and carbon costs. Based on these comprehensive consideration, this paper establishes a predictive model for investment timing of hydrogen metallurgy projects, takes an example of a Chinese steel enterprise with medium production scale. The research results show that the hydrogen metallurgy project with a hydrogen-rich blast furnace injection technology (hydrogen-rich BF) route is the most economically advantageous after 2026; after 2048, the net income of the hydrogen metallurgy project with a hydrogen-based shaft furnace direct reduction technology (hydrogen-based DRI) route will be greater than the stranded costs of carbon metallurgy projects, making it the most economically advantageous project. However, market dynamics and equipment variations significantly influence project viability.

Investigation on pyrolysis behavior and kinetic analysis of banana tree bark and coal blends in blast furnace injection

Investigation on pyrolysis behavior and kinetic analysis of banana tree bark and coal blends in blast furnace injection

Optimizing Combustion Efficiency in Blast Furnace Injection: A Sustainable Approach Using Biomass Char and Coal Mixtures

Optimizing Combustion Efficiency in Blast Furnace Injection: A Sustainable Approach Using Biomass Char and Coal Mixtures

Co-combustion behavior and catalytic mechanism of high CaO/SiO2 biomass mixed with anthracite for blast furnace injection: Experiment, modeling and DFT investigation

The physical and chemical properties of apricot tree (AT), corncob (CC), and anthracite (CC) were systematically analyzed. Their combustion behaviors and blends were examined using a non-isothermal thermogravimetric method, which revealed the catalytic mechanism of biomass mineral composition in the combustion process. The presence of high CaO content resulted in better combustibility, particularly with an addition ratio of more than 50 % AT, which enhanced anthracite combustion. Kinetic analysis indicated that the random pore model had a better fit than the volume reaction model. At 75 % addition of AT and CC, the lowest apparent activation energies were observed, with values of 100.5 kJ/mol and 110.23 kJ/mol, respectively. Density functional theory calculations demonstrated that the presence of CaO caused reconfiguration in the coal's molecular structure, making it easier for aliphatic chains attached to six-membered rings to detach. The co-combustion process and catalytic combustion mechanism of biomass and coal were discussed, highlighting CaO's ability to remove oxygen-containing functional groups and aliphatic chains, while facilitating O2 diffusion within the molecular structure. Conversely, SiO2 tended to generate silicates, leading to the deactivation of CaO's catalytic effect.

Feasibility analysis and environmental impact evaluation of biochar derived from mango pit for blast furnace injection

Biochar, produced by the pyrolysis of carbon–neutral biomass, has great potential to replace pulverized coal (PC) injection in blast furnace (BF) ironmaking. Herein, this study aimed to develop a low-ash and low-alkali metal biochar from mango pit (MP) and evaluate its environmental impact as an alternative fuel for BF ironmaking. This paper first studied the feasibility of mango pit biochar (MPB) as an alternative fuel. Compared with other preparation conditions, MPB prepared at 600 °C for 60 min (MPB-600–60) had the most similar fuel performance to PC, which was confirmed by principal component analysis (PCA). Moreover, MPB-600–60 exhibited lower ash and alkali metal content compared to PC. The co-combustion experiment demonstrated that MPB-600–60 could promote the combustion of mixed fuel, and the optimal combustibility was achieved when the addition ratio of MPB-600–60 was 80%. Comprehensive life cycle assessment (LCA) revealed that the reduction of global warming potential (GWP) amounted to 220 kg CO2 eq/tHM if MPB 100% replaced PC. These results indicated that MPB could significantly reduce the greenhouse gas emissions and the environmental impact of BF ironmaking. This study provides a novel and promising approach for developing low-carbon and clean alternative fuels in BF ironmaking.

Cross-upgrading of biomass hydrothermal carbonization and pyrolysis for high quality blast furnace injection fuel production: Physicochemical characteristics and gasification kinetics analysis

Cross-upgrading of biomass hydrothermal carbonization and pyrolysis for high quality blast furnace injection fuel production: Physicochemical characteristics and gasification kinetics analysis

Municipal solid waste gasification by hot recycling blast furnace gas coupled with in-situ decarburization to prepare blast furnace injection of hydrogen-rich gas

Waste-to-energy is one of the most effective methods to save energy and reduce carbon emissions. This paper proposes a novel process of municipal solid waste (MSW) gasification by hot recycling blast furnace gas (BFG) coupled with in-situ decarburization to prepare blast furnace injection of hydrogen-rich gas. MSW gasification by the hot BFG is conducted by using Aspen Plus software coupled with equilibrium model or kinetic model. Compared to the equilibrium model, kinetic simulation results exhibit good agreement with the experimental results. Moreover, the technological analysis is also performed to investigate the coupled effects of gasification temperature, MSW/BFG ratio, and steam/MSW ratio on the H2-rich syngas generated from MSW gasification. The results reveal that all the investigated influencing factors have been found with a significant effect on the H2-rich syngas formation. The 25.95 vol% of H2 and 37.20 vol% of CO during MSW gasification by the hot BFG are achieved at a gasification temperature of 900 °C, steam/MSW ratio of 0.46 kg/kg, and MSW/BFG ratio of 0.34 kg/Nm3.

Numerical investigation of the impact of injecting coke oven gas on raceway evolution in an ironmaking blast furnace

Using coke oven gas (COG) as a cost-effective alternative fuel in the ironmaking blast furnace has gained considerable attention. However, its dynamic impact on the raceway's shape and size remains to be determined. This study presents a comprehensive investigation using a 3D transient Computational Fluid Dynamics (CFD) model to study and compare the effects of injecting COG and reformed COG on the dynamic raceways of blast furnaces. The complex multiphase flow and thermochemical behaviours associated with the combustion of COG and reformed COG in the dynamic raceway are quantified and compared in terms of the evolution of the raceway profile, gas temperature, and species distribution when using different injection rates. The results indicate that injecting COG leads to forming a larger raceway size by 5 % compared to reformed COG. The gas temperature along the tuyere centerline exhibits higher values by 2 %−7 %, while the molar fraction of CO and CO2 increases by 30 % and 15 %, respectively. Moreover, the molar fraction of O2 and H2 shows a 3 % increase under similar injection rates. These findings help to understand the potential of reformed COG injection to further reduce carbon emissions compared to COG injection in blast furnaces.

New insights into the influence of hydrogen on important parameters of blast furnace

In the pursuit of curbing carbon dioxide emissions, hydrogen is being explored as a substitute for coke in the blast furnace smelting process. This research delved into the potential of hydrogen to mitigate carbon emissions, employing a hydrogen-rich blast furnace model for calculations. A novel approach for preheating hydrogen through blast furnace injection was proposed, accompanied by a more scientifically rigorous CO2 assessment method. This approach encompassed not only CO2 generation during blast furnace smelting but also factors in CO2 emissions from the hot blast stove and hydrogen preheating stove. Simulation outcomes underscored the significant carbon reduction potential of hydrogen. However, it's noteworthy that introducing preheated hydrogen into the blast furnace didn't guarantee lower CO2 emissions. For hydrogen volumes below 300 m³/THM, CO2 emissions rose as hydrogen temperature increased. Conversely, when hydrogen injection surpasses 300 m3/THM, elevated hydrogen temperatures correspond with decreased CO2 emissions. The most significant reduction in CO2 emissions, amounting to 26.1%, occurred when hydrogen at 1250 °C was blown at a rate of 350 m³/THM. These findings contribute to a more comprehensive understanding of hydrogen's potential for emissions reduction, underscoring the importance of intricate factors in optimizing its implementation in the blast furnace smelting process.

Application of catalysts in biomass hydrothermal carbonization for the preparation of high-quality blast furnace injection fuel

The low energy density of biomass is a crucial limitation for their application in the steel industry. This study used catalyst-catalysed hydrothermal carbonization (HTC) to prepare higher-quality hydrochar from biomass. The effects of acid-base homogeneous catalysts (Fe(NO3)3·9H2O and CaO), liquid phase product (circulating water) and carbonization temperatures on the physicochemical properties and microscopic morphology of hydrochars were investigated. The results showed that higher carbonization temperature, circulating water and Fe(NO3)3·9H2O all raised the higher heating value (HHV) of hydrochar. When 4% of Fe(NO3)3·9H2O was added, the HHV of hydrochar reached 30.05 MJ/kg, which was 1.15 times higher than without catalysts. The above three conditions can also make the ordering degree in the carbonaceous structure lower ordered and enhance the reaction performance of the hydrochar. Meanwhile, the addition of Fe(NO3)3·9H2O at 240 °C can reduce the hydrochar ignition and burnout temperatures and enhance the combustion performance. Moreover, it was demonstrated that circulating water promoted the HTC more than deionized water. In conclusion, adding Fe(NO3)3·9H2O or circulating water to the HTC process can produce higher-quality hydrochar.

Enhancement of hybrid combustion of semi-coke and bituminous coal by rare earth oxides

ABSTRACT The use of semi-coke instead of anthracite coal for blast furnace injection to reduce ironmaking costs is becoming increasingly popular. To optimise the usage of semi-coke, it is essential to investigate the mixed combustion of semi-coke and bituminous coal. Within this study pulverised coal combustion was analysed using a thermogravimetric analyser. The results showed that the proportion of semi-coke in the mixed pulverised coal did not exceed 30%. However, 1 wt-% La2O3 as a catalyst increased the proportion of semi-coke by 15%. In addition, the kinetics of combustion of pulverised coal was investigated using the Flynn Wall Ozawa method and the catalyst reduced the activation energy of the reaction. The average activation energy decreased from 84.24 KJ/mol to 74.59 KJ/mol, especially at a conversion of 0.4, with a maximum reduction of 17.3%. Overall, La2O3 is an effective catalyst to increase the utilisation of semi-coke for practical industrial applications.

Hydrothermal carbonization of waste furniture for clean blast furnace fuel production: Physicochemical, gasification characteristics and conversion mechanism investigation

This study aimed to investigate the physical and chemical characteristics of hydrochar derived from waste furniture through hydrothermal carbonization (HTC) and evaluate its suitability as a fuel for blast furnace injection, the formation mechanism of biomass conversion to hydrochar was also systematically investigated. The optimal HTC conditions were determined as 260 °C, liquid–solid mass ratio of 2:1. The resulting hydrochar exhibited a high calorific value of 27.78 MJ/kg, a specific surface area (St) of 3.01 m2/g, and K and Na concentrations of 203 mg/kg and 416 mg/kg, respectively. The apparent activation energy (E) for gasification was measured as 154.54 kJ/mol, indicating its potential as a clean injection fuel for blast furnaces. During HTC, cellulose, hemicellulose, and lignin underwent hydrolysis, decarboxylation, polymerization, and aromatization processes, resulting in the transformation of water-soluble small molecules into polymerized hydrochar and water-insoluble large molecules into polyaromatic hydrochar. This study provides insights into the possibility of replacing fossil fuels in the blast furnace iron-making process.

Kinetic and experimental analysis of the effect of particle size on combustion performance of low-rank coals

Low-rank coal resources are abundant, which is the key to realizing coal high-value utilization. This paper focused on the effect of particle size of low-rank coal on combustion performance by experiment and kinetic analysis, and proved the feasibility and safety of low-rank coal enlarged particle size for blast furnace injection. Form the research results, the explosive, combustion and gasification behavior of samples are related to its volatile content, the oxygen content, the specific surface area and the reactive sites in the coal. Safety is the key to realize the injection high-proportion or even all low-rank coal, and the increasing of particle size can effectively inhibit its explosive and reduce its combustibility. For low-rank coal with 25%-40%, d2 (0.074–0.150 mm) is an appropriate particle size for blast furnace injection, which ensures safety and better combustibility. Furthermore, there are differences in the heat and mass transfer process of different particle sizes during the combustion process by affecting its behaviors such as organic matter consumption and volatile matter removal. The apparent activation energy of coal decreases with the increase of volatile content and particle size.

Ash melting behavior and mechanism of high-calcium bituminous coal in the process of blast furnace pulverized coal injection

Abstract High-calcium bituminous coal has the advantages on combustibility, but its ash melting point is low, and it is easy to slag in blast furnace injection process. In order to explore the ash melting slag formation mechanism of high-calcium bituminous coal, the mineral evolution of ash in the combustion process of high-calcium bituminous coal and the influence of ash components on the liquid formation in the melting process were studied. The results showed that the melting behavior of ash gradually occurs with the change in the morphology, and the main mineral transformation is carried out around different deposition forms of Ca and Si. The liquid phase formation of ash at high temperature is the essential reason of its melting behavior. The higher the content of CaO, the higher the starting temperature of the liquid phase formation. The higher the content of SiO2, the lower the starting temperature of the liquid phase formation, and the more the liquid phases generated at a given temperature. Increasing the content of Al2O3 can expand the temperature range of reducing the formation of ash liquid phase to 1,473–1,673 K. When the temperature is above 1,573 K, Fe2O3 can promote ash liquid phase formation.

Investigation on co-combustion behavior and kinetic analysis of bamboo char/waste plastics (PVC) hydrochar

The combustion properties of bamboo char (BC), PVC hydrochar and blends were studied by non-isothermal thermogravimetric method. The high carbon structure order and ash content of BC are the main reasons for its poor combustion performance. Blending with PC can effectively improve its combustion performance, and there is an obvious negative synergistic effect between PC and BC, which is most obvious when the content of PC is 40%. The accuracy of fitting degree of RPM model is better than that of VM model, the activation energies (E) of BC and PC are 102.1 kJ/mol and 60.9 kJ/mol, respectively. Finally, a coupling process of fuel preparation and blast furnace injection was proposed, and the environmental and economic benefits were calculated. The total cost can be reduced by 29.18 CNY/T, carbon emissions can be reduced by 73.16 KG/T, and the maximum proportion of PVC hydrochar is only 40%.

Preparation of Biomass Hydrochar and Application Analysis of Blast Furnace Injection

Hydrothermal carbonization (HTC) technology was used to carbonize and improve biomass raw material to obtain hydrochar. The effects of HTC temperature and holding time on the yield, composition, structure, combustion behavior, and safety of hydrochar were studied systematically. In addition, the results show that with the increase in HTC temperature and the prolongation of holding time, the yield of hydrochar gradually reduces, the fixed carbon content of hydrochar increases, the volatile content decreases, and a large number of ash and alkali metals enter the liquid phase and are removed. Further, the analysis of the combustion properties and the structure of hydrochar can be observed in that, as the HTC process promotes the occurrence of polymerization reactions, the specific surface area gradually reduces, the degree of carbon ordering increases, and the combustion curve moves toward the high-temperature zone and gradually approaches bituminous coal. Since biomass hydrochar has the characteristic of being carbon neutral, blast furnace injection hydrochar can reduce CO2 emissions, and every 1 kg/tHM of biomass hydrochar can reduce CO2 emissions by 1.95 kg/tHM.

Improvement and prediction on high temperature melting characteristics of coal ash

Abstract In order to improve the high temperature melting characteristics of bituminous coal with low ash melting point, three kinds of anthracites were used to improve the ash melting characteristics of blended coal to meet the requirement of blast furnace injection. The complete melting temperature of pulverized coal ash had been calculated by using FactSage thermodynamic calculation software. The results showed that after adding different proportions of anthracite with high ash melting point, the deformation temperature, softening temperature, hemispherical temperature, and flow temperature of the blended coal increased. After adding different proportions of Yang Quan anthracite, compared to Bu Lian Ta bituminous coal, the ash melting point of blended coal increased by 98, 136, 149, and 170 K, respectively. The relationship between the ash melting point of pulverized coal and the calculated value of ash complete melting temperature was obtained as: T ST = 0.7098T C + 257.98.