Steel Mill Scale Research Articles

Selection of internal design of crystallizer sleeves for continuous casting of 200 mm billets

The crystallizer is the most critical and most important functional unit of a continuous casting machine (hereinafter referred to as CCM). It is the main technological unit of the CCM, an assembly for removing heat during the solidification of the solidifying metal and the formation of the ingot. The main requirement for the crystallizer is to provide maximum heat removal from the solidifying steel to the cooling water, and to obtain a strong ingot shell with a good surface at the outlet of the crystallizer, which would not be destroyed by the heat of the liquid phase and the ferrostatic pressure. During the reconstruction of the CCM by the contractor company, drawings of crystallizers and crystallizer sleeves with a double‑cone internal geometry for casting 200 mm continuous cast billets were developed. The 200 mm continuous cast billet is a billet for the production of hot‑rolled seamless steel pipes. During the operation of the crystallizer sleeves with a double‑cone internal geometry, an accelerated wear of the protective coating in the lower part of the sleeve was noted, as well as an increased rejection of hot‑rolled pipes due to defects on the outer surface of the pipes. In order to identify the cause of the defect formation, complex metallographic studies of the outer surface of the pipes were carried out. As a result of the metallographic study, surface defects classified as steel mill scale on the outer surface of the pipes were identified. To minimize the “steel mill scale” defect and reduce the wear of the protective coating of the crystallizer sleeves, work was carried out to select the optimal conditions for the crystallization of the continuous cast billet: the use of crystallizer sleeves with a three‑cone internal geometry compared to a double‑cone was investigated; maintaining the temperature difference of the water at the inlet and outlet of the crystallizer within specified limits (ΔT) was tested. It was found that the use of a crystallizer sleeve with a three‑cone internal geometry for casting 200 mm billets and the stable behavior of the ΔT parameter made it possible to ensure the required quality of the surface of seamless pipes, reduce the wear of the protective coating of the crystallizer sleeves and increase the productivity of the CCM.

A Review on Engineering Behaviour of Sustainable Concrete with Steel Mill Scale and the Effect of Admixture on Workability Improvement

Abstract: The integration of chemical admixtures and alternative materials in concrete production has become a focal point in advancing construction technologies. This study investigates the combined effects of superplasticizers and mill scale on the workability and compressive strength of M30 grade concrete. Three different superplasticizers—Auramix 200, SikaPlast®-3069 NS, and Master Polyheed 8126—are evaluated for their performance enhancements in concrete. Additionally, mill scale, an industrial by-product, is utilized to partially replace sand in varying proportions (0%, 20%, 40%, 60%, 80%, and 100%) to assess its viability as a sustainable aggregate alternative. The experimental phase is divided into three stages: initially assessing the workability and compressive strength of M30 concrete without admixtures; subsequently incorporating mill scale to observe its effect on concrete properties; and finally combining mill scale with each superplasticizer to maintain workability while evaluating the compressive strength. Slump cone tests are conducted to measure workability, and compressive strength tests are performed at 7, 14, and 28 days. Results indicate that the inclusion of superplasticizers significantly enhances workability, with Auramix 200 showing the highest improvement. The addition of mill scale up to 60% replacement level increases compressive strength, with a notable peak at 60% replacement for both plain and superplasticizer mixes. However, higher replacement levels (80% and 100%) result in reduced strength and workability. Among the superplasticizers, Auramix 200 exhibits the best overall performance in conjunction with mill scale. This study concludes that the strategic use of superplasticizers and mill scale can produce high-performance, sustainable concrete. Future research should explore long-term durability aspects and optimize mix designs for broader applications in construction

Engineering Behaviour of Sustainable Concrete with Steel Mill Scale and the Effect of Admixture on Workability Improvement

Abstract: The integration of chemical admixtures and alternative materials in concrete production has become a focal point in advancing construction technologies. This study investigates the combined effects of superplasticizers and mill scale on the workability and compressive strength of M30 grade concrete. Three different superplasticizers—Auramix 200, SikaPlast®-3069 NS, and Master Polyheed 8126—are evaluated for their performance enhancements in concrete. Additionally, mill scale, an industrial by-product, is utilized to partially replace sand in varying proportions (0%, 20%, 40%, 60%, 80%, and 100%) to assess its viability as a sustainable aggregate alternative. The experimental phase is divided into three stages: initially assessing the workability and compressive strength of M30 concrete without admixtures; subsequently incorporating mill scale to observe its effect on concrete properties; and finally combining mill scale with each superplasticizer to maintain workability while evaluating the compressive strength. Slump cone tests are conducted to measure workability, and compressive strength tests are performed at 7, 14, and 28 days. Results indicate that the inclusion of superplasticizers significantly enhances workability, with Auramix 200 showing the highest improvement. The addition of mill scales up to 60% replacement level increases compressive strength, with a notable peak at 60% replacement for both plain and superplasticizer mixes. However, higher replacement levels (80% and 100%) result in reduced strength and workability. Among the superplasticizers, Auramix 200 exhibits the best overall performance in conjunction with mill scale. This study concludes that the strategic use of superplasticizers and mill scale can produce high-performance, sustainable concrete. Future research should explore long-term durability aspects and optimize mix designs for broader applications in construction.

Development of a Waste Management Strategy in a Steel Company

The management of waste, especially ferrous waste, poses great problems in the steel industry due to strict regulations on preventing, reducing, or even eliminating the factors that generate a high degree of environmental pollution (landfills resulting from the steel industry and adjacent industries—mining, energy, etc.). The present paper presents a synthesis of the specialized literature regarding the processes used, both worldwide and nationally, regarding the transformation of raw materials (ores or concentrates) and iron-containing waste (steel mill dust, mill scale and scale, sludge from agglomeration factories, sideritic waste, etc.) into by-products that can be used in the steel industry. For technological reasons, the option of pelletizing powdered waste was applied—in laboratory conditions, according to its own recipes, with results that justify the application of the technology on an industrial scale (appearance after hardening; drop resistance). The aim of the paper was to identify a practical solution; based on this solution, original conceptual models of organizational strategies (management and processing, respectively, recovery of ferrous waste within steel companies) were developed, such as a concentration strategy, diversification, vertical integration, etc. Within graphical representations of the proposed strategies, other processing variants were mentioned: agglomeration; briquetting.

Experimental investigation on static/dynamic response and γ/n shielding of different sustainable concrete mixtures

Concrete has an influential role in the construction industry as it is a prominent building element that affects the present infrastructure and the construction industry's economy. There is a considerable consumption of raw materials needed for concrete production since crushed stone production was increased in the last decades. Thus alternatives for aggregates are highly recommended solutions for such problems. Steel slag and mill scale are considered sustainable contenders for natural resources of structural materials.Nuclear bombs accompanied with radiations and dynamic loads are considered one of the major disasters that threaten human lives and structures. Therefore, this research investigates the effect of utilizing by-product materials as coarse and fine aggregates to manufacture sustainable concrete, probably with novel static and dynamic performance and radiation attenuation capability. This issue could be done by substituting crushed stone aggregates by steel slag and silica sand by mill scale in concrete production. Fresh and hardened properties of concrete were experimentally explored. Workability, compressive, tensile and flexural strength, impact resistance, and linear attenuation capability were the major evaluated characteristics in this research work. The achievements of this study showed that a superior static and dynamic performance by up to 81.67% and 178.39% compared to normal concrete, respectively, could be achieved by utilizing steel slag and mill scale in concrete fabrication besides its considerable environmental benefits and economic affordability. Also, the radiation attenuation capability was enhanced by up to 84.1% with prepared sustainable concrete mixtures, which makes it a good candidate for radiation shielding. Thus, producing novel structures such as radiation shielding facilities probably with superior dynamic performance.

Study of self compacting concrete with partial replacement of fine aggregate with steel mill scale

Study of self compacting concrete with partial replacement of fine aggregate with steel mill scale

Preliminary study on utilization of steel mill scale in concrete

Modern society is witnessing rapid advancement in science and technology, which increases the natural resource demand. Due to these advancements, an extra burden comes on such resources. Due to this, an alternative approach requires to fulfill these demands. In the same context, concrete is one of the world's most widely used building materials. So, in present study aims to provide a sustainable alternative to one of the principal constituents of concrete, i.e., sand. Natural river sand is typically used as a fine aggregate in concrete. The water table is lowered due to the extraction of natural river sand from the river bed, posing another environmental concern. Thus, it is essential to find a substitute for river sand. The present study attempts to find an alternative in the form of the Steel Mill Scale (SMS), which is obtained as a byproduct of the Steel industry. For the study, the fine aggregate was replaced partially by the SMS in various weight-based proportions such as 5%, 10%, 15%, 20%, and 25%. Super-plasticizers were added in varying amounts to keep the Constant workability. Due to its higher water absorption rate, SMS was used in surface-saturated dry condition. All concrete properties, including compressive strength, split tensile strength, flexural strength, density, abrasion resistance, water absorption, and porosity, were tested using M30-grade concrete. Strength tests were conducted at the age of 7, 28, and 56 days, while all the other tests were done at 28 days only. In addition to all of these, XRF was performed on SMS to know the different oxides present in the material. Due to iron availability in SMS, compressive strength results were desirable up to 15% replacement, and in split tensile strength increment was clearly visible up to 15% replacement. Based on the all results, 15% replacement gives an encouraging result.

Performance of green concrete paving block imbibed with industrial scrap steel mill scale for sustainable construction

The utilization of industrial waste materials in concrete compensates the shortage of natural resources by not only solving the problem due to disposal of wastes but also by developing alternative solutions to protect the environment as well as reduction in the area requirement for landfill. The concrete made with such wastages using less energy during its production and eco-friendly is called as Green Concrete. Variety of industrial wastes is employed as whole or partial substitution for coarse or fine aggregate. Steel mill scale is one such kind of waste materials produced as a result of hot process of rolling of steel in steel companies with rich source of iron content with least impurities. This research study investigates the viability of adopting steel mill scale as a partial substitute material for fine aggregate (M-sand). The current study investigates the influence on fresh and hardened concrete paving blocks and its properties, when M-sand is replaced at 0%, 20%, 40%, 60%, 80%, and 100% with steel mill scale using a mix ratio of 1:1.6:2.1 at sustained water-cement ratio value of 0.5 and target strength at 28 days of 30 Mega Pascal. Physical and chemical characterisation of the materials, concrete compressive strength, concrete split tensile strength, water absorption, and also micro-structural examination of hardened paving blocks are experimentally investigated. Results suggest that 60% of the replacements outperformed the originals. The research findings point towards the feasibility of producing paving blocks from scrap steel mill scale for enhancing environmentally friendly construction practices and sustainable pavement infrastructure.

STUDY OF SCC WITH PARTIAL REPLACEMENT OF FINE AGGREGATE WITH STEEL MILL SCALE

STUDY OF SCC WITH PARTIAL REPLACEMENT OF FINE AGGREGATE WITH STEEL MILL SCALE

Electrical resistivity and compressive strength of cement mortar based on green magnetite nanoparticles and wastes from steel industry

Smart emerging materials are intelligent composites that have properties different from normal materials. Conductive building materials, including conductive cement mortar and concrete, may be defined as a mixture containing a certain amount of electrically conductive components (filler) designed to enable the conduction of electricity. They have amazing infrastructure applications, including building surface heating, pavement de-icing, electromagnetic defence, cathodic protection, and enhancing foundations and buried ground grid systems. In this study, green magnetite nanoparticles (Fe3O4) are synthesized using plant-mediated rout, characterized, and used as electro-conductive fillers in cement-mortar that are formulated using two types of industrial wastes from the steel industry; the steel slag (SS) and mill scale (MS) as fine aggregates instead of sand. The effect of the water/cement ratio, the content of the green conductive filler, and the industrial wastes on the electrical resistivity and compressive strength of the prepared mortars are investigated. Conventional cement mortar samples are prepared and tested similarly for comparison purposes. The results revealed that the electrical resistivity decreased and compressive strength increased with increasing the content of the conductive fillers, and response surface analysis results confirmed that smart cement-steel slag mortars with an optimum electrical resistivity of 8.83 Ω.m. and compressive strength of 36.08 MPa could be formulated with 0.55 w/c and incorporation of 8.15 wt% mill scale, 45.6 ml green magnetite nanoparticles (NPs) colloid. The developed mathematical models were estimated with high regression coefficients and a % error of less than 5.5, confirming their accuracy. Mathematical correlations between electrical resistivity and compressive strength are developed.

A STUDY OF CONCRETE INCORPORATING STEEL MILL SCALE WASTE

This paper presents the effective utilization of industrial waste steel mill scale in concrete. Tests were performed on concrete specimens incorporating 10%, 20%, 30%, and 40% steel mill scale by weight of sand and a control specimen. Results were assessed in terms of workability, compressive strength, flexural strength, and durability. The compressive and flexural strength of concrete incorporating a 20% steel mill scale was recorded higher as opposed to control and other percent replacement specimens. It was also observed that the durability and resistance against sulphate attack of concrete enhanced as the replacement proportion of mill scale were increased. Furthermore, the higher specific gravity of mill scale waste makes it a suitable material for heavyweight concrete members and radiation shield structures.

In-depth insight into the role of molybdate in corrosion resistance of reinforcing steel in chloride-contaminated mortars

The purpose of this study is to achieve a better understanding of the inhibition mechanism of molybdate as a potential corrosion inhibitor for reinforcing steel embedded in chloride-contaminated mortars. After adding sodium molybdate, mortars with and without admixed chlorides were exposed to chloride solution for evaluating the inhibition behavior of molybdate using electrochemical measurements and microstructural characterization techniques. In addition, the influence of molybdate on mechanical properties, pore structures and hydration products of mortars was also investigated. Although molybdate could yield a negative impact on mortar properties in terms of reduced strength and electrical resistance due to the increased porosity, the improved corrosion resistance was highlighted for steel in mortars containing molybdate. Based on the interactions between steel corrosion products and mill scale at the steel-mortar interface, the possible inhibition mechanisms of molybdate in chloride-contaminated mortars were proposed.

Effect of Accelerated Cooling on Linepipe Steel Mill Scale and Resulting Localized Corrosion Susceptibility

The structure and composition of mill scale on linepipe steel formed with and without accelerated cooling conditions (ACC) was investigated and correlated to localized corrosion susceptibility. The mill scale structure/composition was investigated using scanning electron microscopy equipped with x-ray energy dispersive spectroscopy and electron backscatter diffraction, as well as x-ray diffraction. Localized dissolution of the mill scale was investigated using electrochemical techniques including open-circuit potential measurements, electrochemical impedance spectroscopy, and electrochemical noise measurements in a corrosive phase solution. The various surface analytical and electrochemical techniques indicated that the mill scale formed without ACC consists of a relatively crack-free, thick inner wüstite layer with a thinner magnetite outer layer. However, the mill scale formed with ACC comprised a magnetite layer containing islands of retained wüstite, with some evidence of magnetite/iron eutectoid formation and which exhibited a relatively high density of through-scale cracks. These cracks can provide direct paths that connect the corrosive solution to the steel substrate, leading to a more rapid breakdown of the mill scale. Additionally, the cracks can form a crevice between the mill scale and the steel surface, providing sites for pit initiation and growth. Coefficient of thermal expansion mismatch thermal stress calculations indicate that a magnetite-based scale is more susceptible to cracking/spalling than a wüstite-based scale, resulting in the ACC plate being more susceptible to localized corrosion.

Engineering Behaviour of Sustainable Concrete with Steel Mill Scale

Engineering Behaviour of Sustainable Concrete with Steel Mill Scale

Steel mill scale waste and granite powder waste in concrete production -An experimental study

Fine aggregate is one of the large scale consuming materials in the construction industry. In general, river sand has been used as a fine aggregate for making concrete, mortar, etc. This river sand becoming one of the expensive materials due to its transportation from the source point and rapid consumption in the construction sector. Owing to the above circumstances, the concrete and construction industry needs a substitute for fine aggregate to be found. In this investigation, M20 grade concrete with the replacement of sand by steel mill scale waste and granite powder waste from 10% to 100% with the increments of 10%. This paper presents a detailed experimental study on compressive strength, bulk density, and water absorption of the M20 grade concrete containing steel mill scale and granite powder. The experimental outcomes indicate that the use of steel mill scale and granite powder in concrete showed improvement in the performance of concrete in strength and as well as in durability aspects.

Assessment of Recycling Potential of the Steel Mill Scale in the Composition of Mortars for Sustainable Manufacturing

The purpose of our paper is to assess the recycling potential of the mill scale in the composition of mortars, in order to improve the management of industrial wastes from steelmaking in the electric arc furnaces, by identifying the possible solutions for natural resources conservation. For this purpose, the sand from the mortar compositions was replaced, in different proportions, with the steel mills. We have presented the experimental procedures for the physical and mechanical characterizations of the mortars. The experimental results regarding the replacement of the sand with the mill scale, in order to obtain the mortars, show that both the compressive strength and the flexural strength are inferior to the standard sample. As the proportion of the mill scale (replaced by sand) increases, the mechanical strengths of the two samples decrease below the value of the mechanical strengths of the standard sample.

Effect of Iron-Bearing By-products on the Emission of SO2 and NOx in the Iron Ore Sintering Process

Iron-bearing by-products are rich in iron and carbon and are often reused in the iron ore sintering process. However, there are fewer studies on the effect of them on sintering flue gas pollutants. Four kinds of iron-bearing by-products were chosen to investigate the effect of them on the emission of SO2 and NOx and sinter quality through sinter-pot test. The results showed that all iron-bearing by-products promoted the emission of SO2, while steel slag tailings and mill scale inhibited the emission of NOx, and blast furnace dust and the sintering ESP dust promoted the emission of NOx. The main cause of blast furnace dust and the sintering ESP dust promoted the emission of SO2 and NOx was the residual unburned coke particles in them. The main cause of steel slag tailings and mill scale promoting the emission of SO2 and inhibiting the emission of NOx was the abundant iron oxides and calcium ferrite. In addition, the effect of them on sinter quality was slight. For reducing the emission of sintering flue gas pollutants, the addition ratio of blast furnace dust, steel slag tailings and mill scale should be controlled to be 1–3%, 3–4% and 2–5%, respectively. The sintering ESP dust from the 3rd electric field should not be added to raw materials, and the addition ratio of the dust from the 1st electric field and the 2nd electric field should be controlled to be 2–3%.

Corrosion Behavior of Reinforcing Steel with Mill Scale in Concrete

Corrosion of reinforcing steel rebar is a main cause for losing the long-term reliability of concrete structures. When the rebar is corroded, the rust induces cracks and detachment of the cover concrete. On the rebars, the mill scale which is a thick oxide film is formed when the rebar is hot rolled. The role of mill scale on corrosion behavior of rebars in concrete has not been clarified, yet. In this study, the corrosion behavior of rebars with mill scale in concrete was studied using a new accelerated corrosion test we developed. Commercial rebars with 19 mm diameter, which have mill scale of several tens of micrometers in thickness, were used in this study. The corrosion behavior of rebars with and without mill scale in mortar was investigated. To remove the mill scale on the rebar surface, electrolytic polishing was carried out. The rebars with or without mill scale were embedded in mortar with 5.5 mm cover thickness and the sample was cured for 28 days. In order to prompt breakdown of passive film on the rebars, 2.06 M NaCl solution was mixed to the mortar. Using these samples, Hyperbaric-oxygen accelerated corrosion test (HOACT) was carried out [1]. In the HOACT, pressurized oxygen gas is supplied to the sample, and the oxygen reduction reaction on the steel surface is enhanced, which leads to the corrosion acceleration of the steel. In this study, the mortar-covered rebar samples were located in a high pressure gas chamber, and pressurized oxygen gas of 0.6 MPa was supplied. The periods of HOACT were 14, 28 and 56 days. After finishing the HOACT, the samples were embedded in resin, and then the cross section of the sample was observed using an optical microscope. The rust composition was analyzed using Raman spectroscopy measurement. The corrosion of the rebar with mill scale was more significant than that without mill scale. In the case of the sample with mill scale after 14-day HOACT, a rust layer was formed between the steel surface and mill scale, whereas no obvious corrosion was observed on the rebar without mill scale. To investigate the effect of the mill scale on the corrosion resistance of the rebar, anodic polarization measurements of the rebars with and without mill scale were carried out in a saturated Ca(OH)2 solution with Cl-. The pitting potential of the rebar with mill scale was more noble than that of the sample without mill scale. However, when the mill scale was scratched the pitting potential was significantly shifted to the less noble direction and it was below that of the rebar without mill scale. These results show that the mill scale improves the corrosion resistance of the rebar in mortar, whereas the corrosion resistance of the rebar becomes even worth than that of the rebar without mill scale when the mill scale contains defects. After 56-day HOACT of the sample with mill scale, two rust layers were observed above and beneath the mill scale. Raman spectroscopy revealed that the rust layer above the mill scale was mainly composed of a- and g-FeOOH, and the layer just beneath the mill scale was mainly composed of Fe3O4. The rust formed on the sample with mill scale during 14-day HOACT was monolayer just above the steel surface and it was composed only of Fe3O4. It is speculated that the Fe3O4 layer grows under the mill scale at the early stage of corrosion of a rebar. [1] K. Doi, S. Hiromoto, H. Katayama and E. Akiyama, Journal of the Electrochemical Society, 165(9), C582-C589 (2018).

Effect of elevated temperature on the compressive strength of concrete produced with pulverized steel mill scale

Concrete materials in structures are usually exposed to high temperatures during fire. The relative properties of concrete after such an exposure are of great importance in terms of the serviceability of buildings. The effect of partial replacement of cement with pulverized steel mill scale (PSMS) on the compressive strength of concrete cubes was investigated in the first test. Furthermore, the influence of elevated temperatures on the compressive strength of the concrete cubes with cement partially replaced with PSMS was examined. For the second test the cubes were exposed to elevated temperatures ranging from the ambient temperature to 750°C in steps of 250°C for 2 hours and allowed to cool for 24 hours. Based on results of tests, partial replacement of cement with 10 % PSMS is recommended for use in concrete production and resistance to elevated temperature. The studies show that at this replacement, the concrete compressive strength is not adversely affected when the elevated temperature reaches 500°C. http://dx.doi.org/10.4314/njt.v36i4.6

INVESTIGATIONS ON OPERATION OF ROTARY TILTING FURNACES

Rotary tilting furnace (RTF) is a new type of fuel furnaces, that provide the most efficient heating and recycling of polydisperse materials. The paper describes results of the investigations on thermal processes in the RTF, movement of materials and non-isothermal gas flow during kiln rotary process. The investigations have been carried out while using physical and computer simulations and under actual operating conditions applying the pilot plant. Results of the research have served as a basis for development of recommendations on the RTF calculations and designing and they have been also used for constructional design of a rotary tilting furnace for heating and melting of cast iron chips, reduction smelting of steel mill scale, melting of aluminum scrap, melting of lead from battery scrap. These furnaces have a high thermal efficiency (~50 %), technological flexibility, high productivity and profitability. Proven technical solutions for recycling of ferrous and non-ferrous metals develop the use of RTF in the foundry and metallurgical industry as the main technological unit for creation of cost-effective small-tonnage recycling of metal waste generated at the plants. The research results open prospects for organization of its own production for high-quality charging material in Belarus in lieu of imported primary metal. The proposed technology makes it possible to solve environmental challenge pertaining to liquidation of multi-tonnage heaps of metal-containing wastes.