Carbonation Of Steel Slag Research Articles

Sulfate-Resistant Clinker Base Cement with New Secondary Main Constituents: A Technical, Economic, and Environmental Analysis

The Spanish cement sector must adapt its production model to a green economy model. This study focuses on the use of new secondary main constituents (SMCs) suitable for a cement plant that specializes in sulfate-resistant (SR) cement production, defining a framework of technical conditions for their usage and their economic and environmental feasibility. Low-calcium-carbonate-content albero, steel slags, and iron silicate were the tested SMCs; however, they are not currently permitted in cement manufacture. CEM I 42.5 R-SR 3 (type I-SR) was mixed with 5%, 20%, and 30% of these new SMCs. XRF, XRD, leaching and other chemical tests, setting, and hardening tests were performed with no significant issues. Albero is the best option, on the whole, because of the following characteristics: availability, >100 Mt; proximity, 3 km; and acceptable compressive strength level. However, black slag cement with 30% SMC after 28 days shows the best performance, with a compressive strength of 41.3 MPa compared to 35.3 MPa for albero cement and 56.5 MPa for the type I-SR reference. Albero and steel slag at 30% content are the best option according to the cost savings of 32% (−31.5 EUR/t and −31.6 EUR/t, respectively) compared to the type I-SR reference. Regarding the carbon footprint, albero and steel slag at 30% content have the least impact, showing a 31% reduction (−254.8 kg CO2/t and −255.2 kg CO2/t, respectively) compared to the type I-SR reference. The studied SMCs meet the analytical conditions and—with the corresponding regulatory changes—offer potential cost savings for SR cement production, exhibiting a competitive advantage.

Resource efficiency and sustainability of carbonated steel slag -cement with sodium salicylate

Resource efficiency and sustainability of carbonated steel slag -cement with sodium salicylate

Life Cycle Assessment and Environmental Impact Evaluation of CCU Technology Schemes in Steel Plants

Greenhouse gas emissions are significant contributors to global warming, and steel enterprises need to find more efficient and environmentally friendly solutions to reduce CO2 emissions while maintaining high process efficiency and low production costs. Carbon capture and utilization (CCU) is a promising approach which can convert captured CO2 into valuable chemicals, reducing dependence on fossil fuels and mitigating climate change. This study uses life cycle assessment (LCA) to compare the environmental impacts of BF-BOF steel plants with and without CCU. When evaluating seven scenarios, including three carbon capture and two carbon utilization technologies, against a baseline, the results demonstrate significant environmental benefits from implementing CCU technologies. Although the activated carbon TSA route for CO2-based methanol production showed good environmental performance, its toxicity risks highlight the advantages of combining TSA with steel slag carbonation as a better non-toxic solution.

Evaluating the carbon sequestration behavior and microstructure evolution of sedimentary carbonates of granular γ-C2S

Evaluating the carbon sequestration behavior and microstructure evolution of sedimentary carbonates of granular γ-C2S

Enhancing mechanical properties of carbonated steel slag through surfactant-assisted CaCO3 crystallization

Enhancing mechanical properties of carbonated steel slag through surfactant-assisted CaCO3 crystallization

Enhanced Carbon Capture through Mineral Carbonation of Steel Slag: A Sustainable Approach to CO2 Sequestration

Enhanced Carbon Capture through Mineral Carbonation of Steel Slag: A Sustainable Approach to CO2 Sequestration

The Utilization of Carbonated Steel Slag as a Supplementary Cementitious Material in Cement.

Carbon emission reduction and steel slag (SS) treatment are challenges in the steel industry. The accelerated carbonation of SS and carbonated steel slag (CSS) as a supplementary cementitious material (SCM) in cement can achieve both large-scale utilization of SS and CO2 emission reduction, which is conducive to low-carbon sustainable development. This paper presents the utilization status of CSS. The accelerated carbonation route and its effects on the properties of CSS are described. The carbonation reaction of SS leads to a decrease in the average density, an increase in the specific surface area, a refinement of the pore structure, and the precipitation of different forms of calcium carbonate on the CSS surface. Carbonation can increase the specific surface area of CSS by about 24-80%. The literature review revealed that the CO2 uptake of CSS is 2-27 g/100 g SS. The effects of using CSS as an SCM in cement on the mechanical properties, workability, volume stability, durability, environmental performance, hydration kinetics, and microstructure of the materials are also analyzed and evaluated. Under certain conditions, CSS has a positive effect on cement hydration, which can improve the mechanical properties, workability, bulk stability, and sulfate resistance of SS cement mortar. Meanwhile, SS carbonation inhibits the leaching of heavy metal ions from the solid matrix. The application of CSS mainly focuses on material strength, with less attention being given to durability and environmental performance. The challenges and prospects for the large-scale utilization of CSS in the cement and concrete industry are described.

Elevating carbonation efficiency and CO2 capture capacity of steel slag by sodium tripolyphosphate (STP): The role of CaCO3 morphology modification

Elevating carbonation efficiency and CO2 capture capacity of steel slag by sodium tripolyphosphate (STP): The role of CaCO3 morphology modification

Synergistic effect of CO2-mixing and steel slag addition on performance and microstructure of concrete

Synergistic effect of CO2-mixing and steel slag addition on performance and microstructure of concrete

Innovative self-healing composites using steel slag and chitosan

Innovative self-healing composites using steel slag and chitosan

Experimental Study on the Effects of Carbonated Steel Slag Fine Aggregate on the Expansion Rate, Mechanical Properties and Carbonation Depth of Mortar.

Steel slag is the main by-product of the steel industry and can be used to produce steel slag fine aggregate (SSFA). SSFA can be used as a fine aggregate in mortar or concrete. However, SSFA contains f-CaO, which is the main reason for the expansion damage of mortar and concrete. In this study, the carbonation treatment of SSFA was adopted to reduce the f-CaO content; the influence of the carbonation time on the content of f-CaO in the SSFA was studied; and the effects of the carbonated SSFA replacement ratio on the expansion rate, mechanical properties and carbonation depth of mortar were investigated through tests. The results showed that as the carbonation time increased, the content of f-CaO in the SSFA gradually decreased. Compared to the mortar specimens with carbonated SSFA, the specimens with uncarbonated SSFA showed faster and more severe damage and a higher expansion rate. When the replacement ratio of carbonated SSFA was less than 45%, the carbonated SSFA had an inhibitory effect on the expansion development of the specimens. The compressive strengths of the specimens with a carbonated SSFA replacement ratio of 60% and 45% were 1.29% and 6.81% higher than those of the specimens with an uncarbonated SSFA replacement ratio of 60% and 45%, respectively. Carbonation treatment could improve the replacement ratio of SSFA while ensuring the compressive strength of specimens. Compared with mortar specimens with uncarbonated SSFA, the anti-carbonation performance of mortar specimens with carbonated SSFA was reduced.

A Review on the Carbonation of Steel Slag: Properties, Mechanism, and Application.

Steel slag is a by-product of the steel industry and usually contains a high amount of f-CaO and f-MgO, which will result in serious soundness problems once used as a binding material and/or aggregates. To relieve this negative effect, carbonation treatment was believed to be one of the available and reliable methods. By carbonation treatment of steel slag, the phases of f-CaO and f-MgO can be effectively transformed into CaCO3 and MgCO3, respectively. This will not only reduce the expansive risk of steel slag to improve the utilization of steel slag further but also capture and store CO2 due to the mineralization process to reduce carbon emissions. In this study, based on the physical and chemical properties of steel slag, the carbonation mechanism, factors affecting the carbonation process, and the application of carbonated steel slag were reviewed. Eventually, the research challenge was also discussed.

Exploring the Effect of Moisture on CO2 Diffusion and Particle Cementation in Carbonated Steel Slag

The study of the mechanisms affecting the preparation parameters of carbonated steel slag is of great significance for the development of carbon sequestration materials. In order to elucidate the mechanism of the influence of moisture on CO2 diffusion and particle cementation in steel slag, the effects of different water–solid ratios and water contents on the mechanical properties, carbonation products, and pore structure of steel slag after carbonation were investigated. The results show that increasing the water–solid ratio of steel slag can control the larger initial porosity and improve the carbon sequestration capacity of steel slag, but it will reduce the mechanical properties. The carbonation process relies on pores for CO2 diffusion and also requires a certain level of moisture for Ca2+ dissolution and diffusion. Increasing the water content enhances particle cementation and carbonation capacity in steel slag specimens; however, excessive water hinders CO2 diffusion. Reducing the water content can increase the carbonation depth but may compromise gelling and carbon sequestration ability. Therefore, achieving a balance is crucial in controlling the water content. The compressive strength of the steel slag with suitable moisture and initial porosity can reach 118.7 MPa, and 217.2 kg CO2 eq./t steel slag can be sequestered.

Accelerated carbonation of steel slag for enhanced carbon capture and utilization as aggregate in alkali-activated materials

Accelerated carbonation of steel slag for enhanced carbon capture and utilization as aggregate in alkali-activated materials

Accelerated Carbonation of Steel Slag and Their Valorisation in Cement Products: A Review

Mineral carbonation emerges as a promising technology to tackle a contemporary challenge: climate change. This method entails the interaction of carbon dioxide with metal-oxide-bearing materials to produce solid carbonates resembling common substances (chalk, antacids, or baking soda). Given that steelmaking industries contribute to 8% of the global total emissions annually, the repurposing of their by-products holds the potential to mitigate CO2 production. Steel slag is a by-product of the metallurgical industry which is suitable for capturing CO2 due to its chemical composition, containing high CaO (24%–65%) and MgO (3%–20%) amounts, which increases the reactivity with the CO2. Moreover, the carbonation process can improve the hydraulic and mechanical properties of steel slag, making this by-product interesting to be reused in building materials. Different studies have developed in the last years addressing the possibilities of reducing the environmental impact of steel products, by CO2 sequestration. This study is dedicated to reviewing the basics of mineral carbonation applied to steel slag, along with recent advancements in research. Special emphasis is placed on identifying parameters that facilitate the reactions and exploring potential applications for the resulting products. The advantages and disadvantages of steel slag carbonation for the industrialization of the process are also discussed.

Effects of sodium aluminate on fleeting semi-dry carbonation and properties of steel slag powders in low concentration CO2 atmosphere

Effects of sodium aluminate on fleeting semi-dry carbonation and properties of steel slag powders in low concentration CO2 atmosphere

Mechanistic study on the promotion of Ca2+ leaching in steel slag through high-temperature solid waste modification.

Indirect carbonation of steel slag is an effective method for CO2 storage, reducing emissions, and promoting cleaner production in the steel industry. However, challenges remain, such as low Ca2+ leaching rates and slag management complexities arising from variations in mineral compositions. To address this, a high-temperature modification process is proposed to alter the mineral composition and facilitate the synergistic utilization of calcium and iron. This study delves into the effects of various solid waste modifications on the leaching of Ca2+ and the total iron content within steel slag. Results show that high-basicity modified slag forms Ca2(Al, Fe)2O5, reducing calcium leaching. Low-alkalinity modified slag produces calcium-rich aluminum minerals and also reduces the leaching of Ca2+ ions. At a basicity of 2.5, coal gangue, fly ash, and blast slag achieve maximum Ca2+ leaching rates of 88.93%, 89.46%, and 90.17%, respectively, with corresponding total iron contents of 41.46%, 37.72%, and 35.29%. Upgraded coal gangue exhibits a 50.02% increase in calcium leaching and a 15.58% increase in total iron content compared to the original slag. This enhances CO2 fixation and iron resource utilization. Overall, the proposed indirect carbonation and iron enrichment modification offer a novel approach for the resource utilization and environmental stability of steel slag.

Enhanced mechanical property of steel slag through glycine-assisted hydration and carbonation curing

Enhanced mechanical property of steel slag through glycine-assisted hydration and carbonation curing

A thorough assessment of mineral carbonation of steel slag and refractory waste

A thorough assessment of mineral carbonation of steel slag and refractory waste

Semi-dry and aqueous carbonation of steel slag: Characteristics and properties of steel slag as supplementary cementitious materials

Semi-dry and aqueous carbonation of steel slag: Characteristics and properties of steel slag as supplementary cementitious materials