Utilization Of Blast Furnace Slag Research Articles

Preparation of Glass–Ceramics Using Low-Pressure Sintering Method for High-Value Utilization of Blast Furnace Slag

Preparation of Glass–Ceramics Using Low-Pressure Sintering Method for High-Value Utilization of Blast Furnace Slag

Comprehensive Utilization and Control Measures of Iron and Steel Slag

With the increase of steel production, the amount of steel slag piled up is on the rise. The article analyzes the current situation of blast furnace slag utilization, elaborates on the current treatment technology of blast furnace slag, and points out that in the future, the utilization of blast furnace slag will develop towards the direction of developing high value-added products, and the sensible heat recovery rate of blast furnace slag is expected to increase. Analyze the current application status and treatment process of converter slag. The comprehensive treatment technology of converter slag is limited by multiple factors, and it is proposed to control converter slag from the production source through "slag recycling".

Developing Geopolymer Composites with Structural Damage Control Potential: Utilization of Blast Furnace Slag, Calcined Clay, and MWCNT

Developing Geopolymer Composites with Structural Damage Control Potential: Utilization of Blast Furnace Slag, Calcined Clay, and MWCNT

Recycling of iron and steel slag for carbon reduction and low‐environment load application

AbstractThe high‐value utilization of blast furnace slag (BFS) and steel slag (SS) as a valuable resource in the field of carbon reduction represents a green revolution, and also is an indispensable path toward breaking through resource and environmental constraints and achieving high‐quality, sustainable development through solid waste utilization in the steel industry. Achieving resource recycling while harnessing the untapped latent energy of resources and exploring their carbon sequestration capabilities has become a crucial avenue for further valorization through waste utilization. BFS and SS discharged from iron‐making or steel‐making furnaces carry a significant amount of latent heat, especially the calcium oxide component in SS, which gives it a unique advantage in the field of comprehensive BFS and SS utilization and carbonation‐based SS utilization. This article discusses the current research status of low‐carbon‐waste‐heat utilization in the production of microcrystalline glass, cementitious materials, functional adsorbents, and other products through front‐end modification of molten BFS and SS. This report also provides an overview of carbon capture by utilizing BFS and SS, offering insights into the research directions for subsequent heat recovery, online quality adjustment, high‐value utilization, and carbon sequestration using BFS and SS in the steel industry.

Experimental Investigation of Sustainable Concrete Production using Blast Furnace as A Cement Substitute- A art of Review

The pursuit of sustainable construction practices has led to a growing interest in alternative materials that can reduce the environmental impact of traditional concrete production. This experimental study focuses on the utilization of blast furnace slag as a substitute for cement in concrete, aiming to assess its mechanical properties, environmental impact, and overall sustainability. The primary objectives of this research are threefold. Firstly, the study seeks to evaluate the mechanical properties of concrete by varying the content of blast furnace slag in the mix, with a specific emphasis on strength, durability, and structural performance. This involves conducting a comprehensive analysis of the concrete's compressive strength, flexural strength, and other relevant mechanical characteristics. Secondly, a life cycle assessment (LCA) will be employed to analyze the environmental impact of the concrete mixtures. This assessment will compare carbon dioxide (CO2) emissions, energy consumption, and overall sustainability of the concrete produced with varying percentages of blast furnace slag. The LCA will provide valuable insights into the environmental implications of using slag as a cement substitute, aiding in the identification of eco-friendlier concrete production practices. Lastly, the research aims to assess the environmental impact of blast furnace slag itself when employed as a cement substitute. This involves examining the production, transportation, and incorporation of blast furnace slag into the concrete mix, providing a holistic view of its sustainability across the entire life cycle. The experimental approach involves the meticulous design of concrete mixes with different percentages of cement replaced by blast furnace slag. The varying mix designs will be tested for mechanical properties, and the data obtained will be used to draw correlations between slag content and concrete performance. In summary, this research endeavors to contribute to the body of knowledge surrounding sustainable concrete production by exploring the mechanical, environmental, and sustainability aspects of utilizing blast furnace slag as a cement substitute. The findings of this study are anticipated to provide valuable insights for the construction industry to adopt more environmentally friendly practices while maintaining or enhancing concrete performance.

Understanding CO2 adsorption in layered double oxides synthesized by slag through kinetic and modelling techniques

As main by-product in iron and steel industry, high value-added utilization of blast furnace slag had received extensive attention. In this paper, a novelty technology was proposed for using blast furnace slag as raw material to obtain excellent CO2 adsorbent-layered double oxides. The characteristics of layered double hydroxides and layered double oxides were investigated in detailed. Most notably, the laminate structure of layered double hydroxides collapsed and the pore structure, particle size distribution and functional groups of the sample had been greatly changed. The layered double oxides were occupied by phases of CaO, Ca12Al14O32Cl2 and MgO. The transformation mechanism of the layered double oxides preparation was obtained. In addition, CO2 concentration and temperature influencing on CO2 adsorption of layered double oxides were studied and established a suitable kinetic model. The optimal kinetic mechanism model of CO2 adsorption by layered double oxides was PSO. The activation energy and pre-exponential factors were 56.88 kJ‧mol−1 and 12.26 min−1, respectively. Ultimately, CO2 adsorption capacity comparison and preliminary economic evaluation were conducted to assess the industrial feasibility of this technology. This work achieved the goals between CO2 reduction and high value-added utilization of solid waste in iron and steel industry.

Incorporating non-destructive UPV into machine learning models for predicting compressive strength in SCM concrete

The utilization of blast furnace slag (BFS) as supplementary cementitious material (SCM) has garnered significant attention due to its potential to reduce ordinary Portland cement consumption and associated CO2 emissions. This study focuses on predicting the compressive strength of SCM concrete containing BFS using various machine learning (ML) models. Specifically, artificial neural network (ANN), Support Vector Machine (SVM), and Decision Tree (DT) models were constructed, with blast furnace slag to binder ratio (BFS/B), age (A), and ultrasonic pulse velocity (UPV) as input parameters, and compressive strength as the output. Prior to model development, extensive statistical analysis was conducted on the dataset. Hyperparameter optimization via grid search was employed to enhance model performance. Evaluation metrics were utilized to compare the predictive capabilities of the models. Results revealed that the ANN model outperformed other ML models in predicting the compressive strength of SCM concrete containing BFS.

Utilization of Blast Furnace Slag as an Enhancer in Masonry Mortars Made with Thermally Treated Waste Concrete Powder

Every year, a massive amount of natural materials are subjected to high temperatures during cement production, resulting in 5% to 8% of total global carbon dioxide (CO2) emissions. The employment of supplementary cementitious materials (SCMs) for developing construction materials could reduce the use of natural materials and CO2 emissions during cement manufacturing. One option to accomplish this is to examine the possibility of producing masonry mortars using thermally treated waste concrete powder (WCP) and ground granulated blast furnace slag (GGBFS). The main objective of the present study is based on this. The study was conducted in two phases. In Phase I, WCP was thermally treated at various temperatures of 0 °C, 300 °C, 500 °C, and 700 °C and then used to prepare mortars at a binder-to-fine aggregate ratio of 1:3. From the strength results obtained in Phase I, a mortar mixture made with 500 °C WCP was selected for Phase II investigation. Mortars were produced by replacing the 500 °C WCP with GGBFS at 0%, 25%, 40%, 60%, 70%, and 85%. It was found that the performance of the mortars was enhanced when GGBFS was used up to 60%. The mortar mixture containing 60% thermally treated WCP and 40% GGBFS produced the optimal physical and mechanical properties. Also, material characterization was carried out on the binders using X-ray fluorescence, scanning electron microscopy, and thermogravimetric analysis. The results indicate that the thermally treated WCPs and GGBFS contain oxides similar to cement, making them suitable for mortar production. In conclusion, the study has shown the feasibility of producing masonry mortars using thermally treated WCP and GGBFS.

Comprehensive utilization of blast furnace slag, municipal sludge and kaolin clay in building brick manufacture: Crystalline transformation, morphology observation and property assessment

At present, the comprehensive utilization of bulk industrial solid waste has attracted wide attention. The recycling of industrial solid waste in building materials not only provides valuable insights for the management of solid waste, but also alleviates the over-exploitation of natural clay resources in the construction industry. In this study, municipal sludge (MS) and blast furnace slag (BFS) were incorporated into kaolin clay (KC) to synthesize sustainable composite bricks, and the sintering effects and engineering properties of bricks were adjusted by changing BFS dosages. The results indicated that the addition of BFS would promote liquid glassy phase production in bricks due to the higher content of alkali/alkaline-earth metal oxides, and the ingredient, viscosity and content of liquid glassy phases could also be regulated through varying the dosage of BFS (0-15%), thereby affecting the pore structure, particle arrangement/consolidation and performance of bricks. Among all synthesized bricks, the optimum dosages of BFS, MS and KC for satisfying the building standard thresholds were 10%, 40% and 50%, with corresponding linear shrinkage, porosity, density, water absorption, compressive and flexure strengths of 12.97%, 18.15%, 1.83 g/cm3, 0.82%, 15 MPa and 38 Mpa, respectively. Finally, mechanism analysis further demonstrated that the formation and evolution of liquid glassy phases were the key responsibility for adjusting the brick micromorphology and performance. Based on this study, using MS and BFS in brick manufacturing benefited the value-added utilization of industrial solid wastes, clean protection of environments and sustainable production of building materials, providing a reference for the process optimization and potential application of MS and BFS wastes in masonry construction.

Utilizing granulated blast furnace slag as an alternative cement binder

This study addresses the challenges associated with the accumulation of technogenic waste in the production of ferrous and non-ferrous metals. We present the findings of global research on the utilization of blast furnace slag as a sustainable alternative to traditional cement binders. Our scientific investigation focuses on the laboratory exploration of replacing cement binders with a highly efficient clinkerless alternative based on blast furnace slag. The fundamentals of formulating clinkerless binders from slag were thoroughly examined for binder design. Through an extensive review, we conducted tests to identify an optimal composition, constrained within the ranges of 70-90% blast-furnace granulated slag, 14% lime, 1.5-2% gypsum, 1.5-2% C-3, and 2-25% microsilica. The outcome of these tests resulted in the development of a novel binder that combines the characteristics and properties of a lime-slag binder with the advantages of a low water consumption binder. This clinker-free binder presents a sustainable solution for construction, serving as a viable substitute for traditional cement. Our findings contribute to the ongoing efforts in adopting environmentally friendly practices in the construction industry.

The Photocatalytic Activity of CaTiO3 Derived from the Microwave-Melting Heating Process of Blast Furnace Slag.

The extraction of titanium-bearing components in the form of CaTiO3 is an efficient utilization of blast furnace slag. The photocatalytic performance of this obtained CaTiO3 (MM-CaTiO3) as a catalyst for methylene blue (MB) degradation was evaluated in this study. The analyses indicated that the MM-CaTiO3 had a completed structure with a special length-diameter ratio. Furthermore, the oxygen vacancy was easier to generate on a MM-CaTiO3(110) plane during the photocatalytic process, contributing to improving photocatalytic activity. Compared with traditional catalysts, MM-CaTiO3 has a narrower optical band gap and visible-light responsive performance. The degradation experiments further confirmed that the photocatalytic degradation efficiency of pollutants by using MM-CaTiO3 was 3.2 times that of pristine CaTiO3 in optimized conditions. Combined with molecular simulation, the degradation mechanism clarified that acridine of MB molecular was stepwise destroyed by using MM-CaTiO3 in short times, which is different from demethylation and methylenedioxy ring degradation by using TiO2. This study provided a promising routine for using solid waste to obtain catalysts with excellent photocatalytic activity and was found to be in keeping with sustainable environmental development.

Experimental study of high-temperature resistance of alkali-activated slag crushed aggregate mortar

Rational utilization of blast furnace slag improves resource utilization rate and is a measure to ameliorate environmental degradation and climate crisis. Alkali-activated slag cementitious material (AASCM) has high temperature resistance and can provide material choice for high temperature environment construction and building fire resistance. In order to solve the thermal incompatibility problem between aggregate and paste of AASCM mortar with natural aggregate, a special type of mortar with alkali-activated slag as cementitious material was examined, which aggregates consisted of crushed and sieved particles of alkali-activated slag paste. The compressive strengths of 126 cubic and 126 prismatic specimens during and after high-temperature treatment were investigated. The test results showed that both the compressive and flexural strengths of the mortar during and after high-temperature treatment decreased with increasing temperature. Moreover, the compressive strength of the mortar after high-temperature treatment was higher than that during the treatment in which strength grade and temperature were constant. The formulated equations for calculating the compressive and flexural strengths during and after high-temperature treatment provided a basis for evaluating the fire resistance of this new type of masonry material. The microstructure and composition of the mortar were analyzed using scanning electron microscopy with energy-dispersive spectrometry and X-ray diffraction. At 600 °C, the mortar gradually produced new products akermanite, merwinite and gehlenite.

High value utilization of waste blast furnace slag: New Ni-CeO2/hBFS catalyst for low temperature CO2 methanation

In the steel industry, large amounts of blast furnace slag (BFS) by-products are inevitably produced and a lot of carbon dioxide is emitted. But at present, slag reuse technology has low added value. In this paper, a high value-added process using blast furnace slag to prepare catalysts for the hydrogenation of carbon dioxide to methane was proposed. Ni-CeO2/hBFS catalyst was prepared by primary wet impregnation using nitric acid modified blast furnace slag (BFS) as a support. CO2 conversion of Ni-CeO2/hBFS catalysts achieved 81.6 % at 350 °C, and the catalyst was not significantly deactivated in a 100 h stability test. The results indicate that: the addition of CeO2 improved the dispersion of Ni particles at high loadings, limited the growth of the Ni particle size and enhanced the synergy between the CO2 adsorption sites, the catalytic active sites and the support, thus improved the catalytic performance at low temperatures. This study provides an effective way for carbon dioxide emission reduction and high-value utilization of blast furnace slag, and developed a Ni-CeO2/hBFS catalyst with superior stability and catalytic performance in long-term operation, thus, the catalyst has great potential for industrial application in the carbon dioxide methanation reaction.

Preparation and performance of composite activated slag-based binder for cemented paste backfill

The utilization of blast furnace slag (BFS) and fly ash (FA) to replace ordinary portland cement (OPC) has become a hot topic in the preparation of low-cost cemented paste backfill (CPB). This study has prepared a composite activated slag-based binder (CASB) using BFS and FA as the basic raw materials and desulfurization gypsum (DG) and cement clinker (CC) as the activator. The optimum ratio of CASB was determined based on the orthogonal test and the efficacy coefficient method. The hydration products and hydration mechanism of CASB materials were further investigated using XRD, TG, and SEM tests; on this basis, the compressive strength of hardened CASB-CPB under different working conditions and the rheological properties of fresh slurry were investigated, and the cost analysis and environmental effects of CASB were carried out. The results show that the optimum ratio of CASB was 15:12:13:60 for FA: CC: DG: BFS; the hydration mechanism of CASB was the coupled alkali-sulfate activation of CC and DG, and the main hydration products were hydrated calcium silicate gels (C–S–H gels) and ettringite (AFt); increasing the mass concentration (Cw) at a constant cement-aggregate ratio (C/A), which caused a significant improvement in the compressive strength at 7 and 28 d while reduced the flowability of the slurry; CASB considerably reduced the filling cost compared to OPC, and effectively immobilization the heavy metals in the tailings. This paper has developed a cement alternative binder of CASB, which has considerable significance for the comprehensive utilization of solid waste, reduction of filling costs, and improvement of economic and ecological benefits of the mine.

Life cycle assessment of a novel blast furnace slag utilization system

A novel system was proposed to realize the high value-added utilization of blast furnace slag. In this study, a comprehensive analysis concerning energy consumption, environmental impact and economic cost of the system was conducted based on the perspective of life cycle. Considering the serious situation of global warming, CO2 emission cost was also included. Main contributors in terms of environmental impact, energy consumption and economic cost were traced through contribution analysis. Global warming potential was the most prominent environmental issue (contributing 65.71% to total impact) and material cost offered the largest economic burden (contributing 90.57% to total cost). However, the adsorption capacity of two products offset total CO2 emission to −6103.62 kg·tslag−1 and decreased total economic cost to 352.26 $·tslag−1, turning the major limitation into a great opportunity. Most energy was consumed in upstream production of chemicals and only 3.18% of the total energy consumption came from the downstream utilization process. According to the sustainability evaluation among three processes, pretreatment performed worst and the hydrotalcite-like compounds synthesis process best. Additionally, sensitivity analysis indicated that overall performance of the system could be efficiently improved by reducing hydrochloric acid consumption. Analysis results in this study exhibited the huge potential of the system in emission reduction and could provide guidance for further improvement.

Highly efficient production of hydrotalcite-like compounds from blast furnace slag

The resource utilization of blast furnace slag was the research hotspot at home and abroad. This study aimed to obtain hydrotalcite-like compounds from slag using co-precipitation method. The optimum process conditions for the synthesis of hydrotalcite-like compounds were investigated using single-factor in a self-designed laboratory-scale system. Furthermore, the synthesis mechanism of hydrotalcite-like compounds was established. The pH of 11.5, precipitation temperature of 343 K, crystallization temperature of 383 K, and crystallization duration of 6– 10 h were shown to be the optimum process conditions for the synthesis of hydrotalcite-like compounds. The leachate formed a typical crystal layered structure of hydrotalcite-like compounds under optimum process conditions through chemical reactions between compounds and sufficient crystallization. The completion of this work provided a new technological path for the utilization of blast furnace slag, which was more conducive to the energy saving and emission reduction of the iron and steel industry.

Experimental Research on Foam Concrete with Partial Replacement of Fine Aggregates by Blast Furnace Slag, Fly Ash, and Glass Powder

Aerated concrete blocks are made according to the design proportions in this project. Cement, fine particles, a foaming agent, and water are the ingredients of foam concrete. Sand prices are significantly rising these days. We may lower the cost of sand by replacing it with a replacement material. In the current investigation, sand is partially substituted by varying weights and quantities of blast furnace slag, fly ash, and glass powder. To gain a better understanding of the utilization of blast furnace slag, Fly Ash, and glass powder in various literatures, their impact on Compressive Strength foam concrete is explored.

Techno-economic analysis of a novel full-chain blast furnace slag utilization system

As the main solid waste in the iron and steel industry, the waste heat recovery and comprehensive utilization of blast furnace slag had great significance for energy conservation and sustainable development. This paper proposed a novel full-chain blast furnace slag utilization system to solve the problem of waste heat recovery and high value-added production. Cascade recovery of slag waste heat was realized by using coal gasification reaction and the waste heat recovery ratio reached 73.61%. Meanwhile, two kinds of high value-added products of X-type zeolite and hydrotalcite-like compounds were synthesized simultaneously by using the beneficial components of blast furnace slag after fully recovering waste heat. Ultimately, the economic feasibility of the system was analyzed from two aspects of investment and profit. Under the reasonable economic assumptions, payback period of the project was 0.14 years, 10-year net present value was $ 326493.98 million, return on investment and internal rate of return were 737.74% and 312.82%, respectively. Through sensitivity analysis, the project could still be profitable in the production year under the condition that the sensitive factors of the system fluctuated within 40%. With great economic benefit and anti-risk ability, the novel full-chain blast furnace slag utilization system had potential in energy saving and emission reduction of iron and the iron and steel industry and the prospect of large-scale application.

Effect of Oily Sludge Treatment with Molten Blast Furnace Slag on the Mineral Phase Reconstruction of Water-Quenched Slag Properties.

Blast furnace slag, which is the main by-product of the ironmaking process discharged at 1450 °C, contains high-quality sensible heat, while oily sludge is the main solid waste produced in the process of gas exploration, storage, and transportation. The energy and resource utilization of blast furnace slag is complementary to the environmentally friendly treatment of oily sludge, which has provided a new idea for the multi-factor synergistic cycle and energy transformation of the two wastes. The pyrolysis of the oily sludge with the molten blast furnace slag was conducted in the current paper. Results showed that the oily sludge was rapidly pyrolyzed, and the heavy metal elements in the oily sludge were solidified. The solidification rate of the heavy metals exceeds 90%, except for vanadium. The reconstituted water-quenched blast furnace slag still has good activity, and it will not affect the further use of the slag after pyrolysis (BFS-P).

A novel synergistic method on potential green and high value-added utilization of blast furnace slag

In order to utilize blast furnace slag resource at low cost, pollution-free, refinement and high value-added, a novel technical route was proposed to collaboratively produce zeolite and hydrotalcite-like compound. In this study, the changing property of slag in the treatment process was investigated and the thermodynamic and kinetic analyses of the leaching reaction were conducted to prove its feasibility. The silica gel and residue liquid were separated effectively from the slag. Then, 13X zeolite and hydrotalcite-like compound were successfully synthesized from water quenching blast furnace slag using hydrochloric acid treatment followed by hydrothermal method and co-precipitation method. The successful formation of 13X zeolite and hydrotalcite-like compound were obtained effectively with good surface morphology and crystal structure. Mass balance of the blast furnace slag utilization process was established. Meanwhile, these two samples exhibited good behavior of CO2 adsorption capacity and enjoyed a promising market prospect. The maximum adsorption capacities of 13X zeolite and hydrotalcite-like compound were 116.48 mg g−1 at 313 K and 149.63 mg g−1 at 873 K, respectively. Finally, the preliminary economic evaluation of the integrated system was conducted, and the economic benefit of 1 kg slag was about 1.281 $.