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Oxygen blast furnace with CO2 capture and storage at an integrated steel mill - Part II: Economic feasibility in comparison with conventional blast furnace highlighting sensitivities (vol 32, pg 189, 2015)

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This article is part II of the series of two papers regarding the application of oxygen blast furnace (OBF) in Ruukki Metals Ltd.’s existing steel mill, located in city of Raahe, Finland. The economic assessment presented in this paper is based on the technical modelling presented in part I of the study. OBF with CCS would lead to large reductions in CO2 emissions but also OBF without CCS would decrease emissions significantly due to decreased coke consumption. From economic point of view, other important consequences of OBF process are increased LPG or LNG (liquefied petroleum gas or liquefied natural gas) consumption, decreased electricity production (increased purchase from markets), required investments and CO2 transportation and storage costs. As CCS processes typically, especially application of OBF is a trade-off between decreased electricity production and decreased emissions. Therefore a correlation between CO2 price development and electricity price development is of interest. In this paper, several sensitivity analyses are presented with different prices for CO2, electricity and other parameters. The results present the sensitivity of different options in terms of economic feasibility for large CO2 reductions in the integrated steel mill based on blast furnace process.
... The reduction in CO 2 emissions was estimated to be in the range of 10-25% [22] (Figure 6). However, the TGR-OBF-CCS technology is relatively complicated, electricity consumption increases, and less electric power can be generated [27,[36][37][38]]. An industrial TGR-OBF installation was put into operation in Anshan, China, in 2012 [39]. ...
... The reduction in CO2 emissions was estimated to be in the range of 10-25% [22] (Figure 6). However, the TGR-OBF-CCS technology is relatively complicated, electricity consumption increases, and less electric power can be generated [27,[36][37][38]]. An industrial TGR-OBF installation was put into operation in Anshan, China, in 2012 [39]. ...
... Acronyms are explained in the text. Outlined based on literature data [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. ...
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The 2018 IPCC (The Intergovernmental Panel on Climate Change’s) report defined the goal to limit global warming to 1.5 °C by 2050. This will require “rapid and far-reaching transitions in land, energy, industry, buildings, transport, and cities”. The challenge falls on all sectors, especially energy production and industry. In this regard, the recent progress and future challenges of greenhouse gas emissions and energy supply are first briefly introduced. Then, the current situation of the steel industry is presented. Steel production is predicted to grow by 25–30% by 2050. The dominant iron-making route, blast furnace (BF), especially, is an energy-intensive process based on fossil fuel consumption; the steel sector is thus responsible for about 7% of all anthropogenic CO2 emissions. In order to take up the 2050 challenge, emissions should see significant cuts. Correspondingly, specific emissions (t CO2/t steel) should be radically decreased. Several large research programs in big steelmaking countries and the EU have been carried out over the last 10–15 years or are ongoing. All plausible measures to decrease CO2 emissions were explored here based on the published literature. The essential results are discussed and concluded. The specific emissions of “world steel” are currently at 1.8 t CO2/t steel. Improved energy efficiency by modernizing plants and adopting best available technologies in all process stages could decrease the emissions by 15–20%. Further reductions towards 1.0 t CO2/t steel level are achievable via novel technologies like top gas recycling in BF, oxygen BF, and maximal replacement of coke by biomass. These processes are, however, waiting for substantive industrialization. Generally, substituting hydrogen for carbon in reductants and fuels like natural gas and coke gas can decrease CO2 emissions remarkably. The same holds for direct reduction processes (DR), which have spread recently, exceeding 100 Mt annual capacity. More radical cut is possible via CO2 capture and storage (CCS). The technology is well-known in the oil industry; and potential applications in other sectors, including the steel industry, are being explored. While this might be a real solution in propitious circumstances, it is hardly universally applicable in the long run. More auspicious is the concept that aims at utilizing captured carbon in the production of chemicals, food, or fuels e.g., methanol (CCU, CCUS). The basic idea is smart, but in the early phase of its application, the high energy-consumption and costs are disincentives. The potential of hydrogen as a fuel and reductant is well-known, but it has a supporting role in iron metallurgy. In the current fight against climate warming, H2 has come into the “limelight” as a reductant, fuel, and energy storage. The hydrogen economy concept contains both production, storage, distribution, and uses. In ironmaking, several research programs have been launched for hydrogen production and reduction of iron oxides. Another global trend is the transfer from fossil fuel to electricity. “Green” electricity generation and hydrogen will be firmly linked together. The electrification of steel production is emphasized upon in this paper as the recycled scrap is estimated to grow from the 30% level to 50% by 2050. Finally, in this review, all means to reduce specific CO2 emissions have been summarized. By thorough modernization of production facilities and energy systems and by adopting new pioneering methods, “world steel” could reach the level of 0.4–0.5 t CO2/t steel and thus reduce two-thirds of current annual emissions.
... • fire coke batteries in a coking plant (COG) [12]; • generate heat, steam, and electricity for the smelter's own needs (COG, BFG) [13,14].; • ignite the sinter mixture on sinter strands in ignition furnaces (a mixture of BFG and COG) [15]; • increase coke savings in blast furnaces (COG, BFG, BOFG, or COREX gas as hot reduction gas after removal (CO 2 )) [16,17]; • fire blast heaters (BFG with COG or oxygen-enriched blast with recirculation of blast furnace exhaust) [18]; • supply heating furnaces in hot rolling mills (COG, BFG) [19,20]. ...
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Converter gas (BOFG) is a by-product of the steel manufacturing process in steelworks. Its usage as a substitute fuel instead of natural gas for fueling a metallurgical furnace seems to be reasonable due to potential benefits as follows: CO2 emission reduction into the ambient air and savings in purchasing costs of natural gas. Results of theoretical analysis focused on implementing converter gas as a fuel for feeding a tunnel furnace for either steel plate rolling, steel sheet hardening in its real working condition or both, are discussed. The analysis was focused on the combustion chemistry of the converter gas and its potential ecological and economic benefits obtained from converter gas usage to heat up steel in a tunnel furnace. Simulations of combustion were conducted using a skeletal chemical kinetic mechanism by Konnov. The directed relation graph with error propagation aided sensitivity analysis (DRGEPSA) method was used to obtain this skeletal kinetic mechanism. Finally, the model was validated on a real tunnel furnace fueled by natural gas. Regarding exhaust emissions, it was found that nitric oxide (NO) dropped down from 275 to 80 ppm when natural gas was replaced by converter gas. However, carbon dioxide emissions increased more than three times in this case, but there is no possibility of eliminating carbon dioxide from steel manufacturing processes at all. Economic analysis showed savings of 44% in fuel purchase costs when natural gas was replaced by converter gas. Summing up, the potential benefits resulting from substituting natural gas with converter gas led to the conclusion that converter gas is strongly recommended as fuel for a tunnel furnace in the steel manufacturing process. Practical application requires testing gas burners in terms of their efficiency, which should provide the same amount of energy supplied to the furnace when fed with converter gas.
... As many steelmaking practices have already reached close to their maximum thermodynamic limits [9,16] and emerging decarbonization options are primarily focusing on incrementally lowering emission, carbon capture is one of the few technologies to offer scalable reductions that rival steel's economic importance and need for decarbonization. Several studies discuss its technical concept [106,107], application design [108,109], and potential [110,111] as a promising decarbonization option. ...
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The iron and steel industry is the largest coal consumer and the most greenhouse gas intensive industry. It consumes about 7% of global energy supply, and conservative estimates report that it is responsible for 7–9% of global greenhouse gas emissions. Decarbonization of the iron and steel industry is thus vital to meet climate change mitigation targets and achieve a sustainable future for the industry. This paper presents a comprehensive and systematic review that considered more than 1.6 million pieces of literature and analyzes in depth a shortlist of 271 studies on the iron and steel industry's decarbonization. Applying a sociotechnical lens that investigates raw materials, iron and steel making processes, steel products making and usage, and waste and recycling, the review identifies the climate footprint of the iron and steel industry. The review also assesses current and emerging practices for decarbonization, identifying 86 potentially transformative technologies. The benefits of decarbonizing the iron and steel industry are considered through energy and carbon savings, financial savings, and other environmental and public health benefits. Barriers to decarbonization are considered across financial, organizational, and behavioral aspects. The review also discusses various financial tools and policy instruments that can help overcome the barriers. Lastly, research gaps are outlined.
... The advantages of H 2 injection were decreases in coke use and CO 2 emissions; these advantages could be combined with economic analysis when considering coke price and CO 2 allowance price, which were expected to increase over time. Recently, the coke price was estimated at US$ 350 t − 1 coke and was projected to increase to 800 t − 1 coke in 2050, by considering the trend of coal price increase [34,35]. In addition, the CO 2 allowance price was US$ 22.1 t − 1 CO2 was projected to increase to US$ 97.0 t − 1 CO2 by 2050, as a result of the increasing importance of greenhouse gas management [36] (Fig. 5). ...
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The steel sector is one of the most carbon-intensive industries, and the sustainable strategies to reduce CO2 emission on integrated mill plants are discussed continuously. By renewable H2 utilization on blast furnace (BF), it is expected to achieve both sustainable operation and CO2 emission reduction. We evaluate the application of the solid oxide electrolysis cell (SOEC) process as a source of H2 for use as an alternative to CO as the reductant in a BF. We mathematically formulated a BF model and developed an integrated BF-SOEC process. We performed techno-economic analysis to suggest the maximum H2 injection for the technical aspect, and demonstrated the process’ economic viability, considering the learning-by-doing effects on the price of the SOEC system. We also estimated the net reduction of global warming potentials and carbon intensity. Our findings showed that the coke replacement ratio ranged from 0.255 ∼ 0.334 kgCoke∙kgH2-1 depending on injection conditions and that 25 kgH2∙tHM-1 was an acceptable maximum injection rate within the stable range of BF operating indexes. We calculated H2 production cost to be US$ 8.84 ∼ 8.88 kgH2-1 in the present, but it is expected to be decreased to US$ 1.41 ∼ 4.04 kgH2-1 by 2050. Economic parity with the existing BF process will be reached between the years 2036 and 2045, depending on the maturity of the SOEC process. Injection of 25 kgH2∙tHM-1 can reduce CO2 emission by 0.26 ∼ 0.32 tCO2-eq.∙tHM-1 We expect that this sustainable strategy to reduce CO2 emission from integrated mill plants will widen applications of H2 utilization in BFs if the economic efficiency of SOEC systems can be increased.
... The recycled gas, which has a high CO content, can act as a reducing agent in the furnace thus allowing to slightly reduce the necessity of coke input, while the oxy-fuel combustion leads to higher CO 2 concentrations in the top gas. Under this configuration, CO 2 emissions can be reduced between 56 % and 84 % with respect to conventional blast furnaces [8,9], with a capture cost in the range 39-58 €/t CO2 [8,10]. ...
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In this paper we present the first systematic review of Power to X processes applied to the iron and steel industry. These processes convert renewable electricity into valuable chemicals through an electrolysis stage that produces the final product or a necessary intermediate. We have classified them in five categories (Power to Iron, Power to Hydrogen, Power to Syngas, Power to Methane and Power to Methanol) to compare the results of the different studies published so far, gathering specific energy consumption, electrolysis power capacity, CO2 emissions, and technology readiness level. We also present, for the first time, novel concepts that integrate oxy-fuel ironmaking and Power to Gas. Lastly, we round the review off with a summary of the most important research projects on the topic, including relevant data on the largest pilot facilities (2–6 MW).
... They showed a potential CO 2 emission reduction of 68 % and outlined the risks of developing a brand new concept for iron and steel production. A second paper showed that the oxygen blast furnace technology for CO 2 capture is convenient from economic point of view only for carbon tax above 50 €/t CO2 (Tsupari et al., 2015). For the sake of reference, the CO 2 emission price in 2017 was around 15 €/t CO2 (Pfahler et al., 2008) and equal to 22 €/t CO2 in the beginning of 2019 (CO2 emission trading, 2018). ...
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Carbon capture (CC), along with the efforts to reduce carbon emissions at the source, is a major action toward the mitigation of climate change and global warming due to emissions of greenhouse gases (GHGs). Carbon emissions amount to 36.3 Gt-CO2 in 2021 from 31.5 Gt-CO2 in 2022, with a drop of about 1.5 Gt-CO2 in 2020 relative to 2019 due to the COVID-19 pandemic. The carbon emissions originate from heat and power, transportation, process industries, and residential activities constitute 47.7, 24.9, 18.9, and 8.5% of the total emissions, respectively. The process industries represent the second large-scale point-source of carbon emissions next to heat and power. Additionally, the process industries have high-intensity carbon emissions up to 0.6–0.8 t-CO2/t-cement, 1.4–2 t-CO2/t-steel, and 2.7–99.2 kg CO2/bbl, with flue gas streams having high CO2 concentration up to 30%. In comparison to 0.4 t-CO2/MWh and 3–16% CO2 in the flue gas from heat and power facilities, these process industries present a highly effective target for CC application. This work reviews and critically discusses the large-scale application of CC to different process industries, namely, cement, iron and steel, oil refinery, and chemicals. CC can be achieved by three main approaches, i.e., post-combustion, pre-combustion, and oxyfuel combustion. Post-combustion and chemical-looping are the common CC approaches utilized in process industries, with the first being widely applied due to its ease of incorporation, and the latter is commonly used in the cement industry. CC with the capacity in the range of 0.4–2 Mt-CO2/yr is planned for cement plants relative to current capacities of 75 kt-CO2/yr. Similarly, CC capacity up to 0.8 Mt-CO2/yr has been integrated into iron and steel plants, in which captured CO2 is utilized for enhanced oil recovery (EOR) applications. In the oil and gas industry, CC has been widely utilized, in the context of gas purification, being an essential gas processing unit, with CC capacities up to 1.4 Mt-CO2/yr, and plans to reach 4 Mt-CO2/yr. CC cost is the main challenge for the widespread implementation of CC in process industries with a wide range of reported costs of USD9.8-250/t-CO2 depending on the process industry and the CC technology used.
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In iron-making plants, the carbon emission problem is significant, and the existing reduction strategies focus on hydrogen utilization. Among the hydrogen production processes, a sulfur-iodine (SI) cycle is one of the most competitive candidates and there is a potential for the modification of the process design specifically targeted for the applications on blast furnaces (BF). We suggest a design for the SI process to produce H2 gas for use as a reductant in the BF during iron smelting. We first validated the conventional SI process by using a commercial process simulator with plant data and simplified the process to increase energy efficiency, profitability, and CO2 mitigation. We calculated the energy efficiency of the various process designs and derived the unit production cost of H2. We discussed the economic feasibility of the SI process in BF applications and showed the potential to mitigate global warming. The energy efficiency of the conventional SI process was estimated to be 32% and was increased to 38% by excluding a sulfuric acid decomposer. The unit production cost was estimated to be 1.22US$ kgH2-1 for the conventional SI process, and 0.80US$ kgH2-1 for the modified SI process of sulfuric acid co-production. The economic feasibility of the SI/MSI cycles was confirmed with a calculation of an internal rate of return and net present value. Also, generated H2 was utilized as an alternative fuel in BF, with an expected coke replacement ratio of 0.168–0.232kgCoke mH2-3 , and for the environmental prospects, an annual reduction was expected to 1077ktCO2-eq in the hot metal production scale of 3.8 Mt y-1.
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