Tons Of Steel Research Articles

Mathematical Modeling on Slag Consumption and Lubrication in a Slab Continuous Casting Mold

In the current study, a two-dimensional mathematical model was applied to investigate the slag lubrication in continuous casting mold of slab through the acquisition of the average slag consumption per oscillation cycle and the shear stress acting on the shell. The thickness and the consumption of the slag in the shell/mold gap and the downward velocity on either side of the liquid slag were monitored at different distances below meniscus and compared with different casting parameters. With the increase of the distance below meniscus from 10 to 300 mm, the thickness of the total slag and the liquid slag decreased, and thickness was within 0.78 to 1.11 and 0.04 to 0.33 mm, respectively. The average slag consumption at four different locations below meniscus was approximate, within 0.0287 to 0.0298 kg/s in three adjacent oscillation cycles. With enough slag consumption, the shear stress was extremely small and was below 80 Pa at 100 and 300 mm below meniscus. With the decrease of the casting speed from 1.6 to 1.2 m/min, the casting superheat from 45 to 25 K and the oscillation frequency from 180 to 100 cpm, and the increase of the oscillation amplitude from 2 to 5 mm, the average slag consumption per ton of steel and the slag consumption (kg/m2) increased, and the consumption was within 0.0245 to 0.0415 kg/s and mainly below 0.40 kg/m2, respectively, which resulted in the improvement of the lubrication in the shell/mold gap.

Modelling of the thermal state and the melting loss of a graphite electrode in the conditions of the evaporative cooling in the arc furnace

The cost of the graphite electrodes amounts greater proportion in the final value of the finished product. This calls for finding opportunities to reduce the maintenance costs of AC and DC furnaces used in foundries. The aim of the study is the creation of a mathematical model and the analysis of the efficiency of the evaporative cooling method in reducing the amount of the graphite electrodes used in small capacity arc furnaces. The mathematical model and the computer program allow determining the thermal state of the electrode and the melting loss of the graphite, the model is developed for a primarily cylindrical electrode and takes into account: the current passing through an electrode, the time of the electrode being in the electrified furnace, and the parameters of the water evaporative cooling. The paper presents the received data about the melting loss of the graphite per ton of steel against the water consumption during the evaporative cooling. The graphite consumption in the arc furnaces of 10–12 tons’ capacity is reduced by 40 %. The recommended water consumption for the evaporative cooling of electrodes for all types of foundry furnaces is 0.1–0.2 m3/h.

Achieving Low Coke Rate Using Calibrated Iron Ore as the Sole Iron Source in Burden Charge During the Successful Recommissioning of Blast Furnace in Syria

In the backdrop of war and amid sanctions on Syria, a mini blast furnace has been successfully recommissioned in Hassia, Syria, and the hot metal produced is used for the production of 130 mm2 mild steel billets, providing import substitution as presently the billets are being imported from countries such as Russia, Ukraine, etc. Emmar Steel (ES) is an integrated steel plant having a production capacity of about 0.5 million tons of steel per annum. ES operates a mini blast furnace (MBF) with a designed capacity of 500 TPD (tons per day) to produce hot metal. ES is the only steel plant, which houses a blast furnace and the first of its kind in the whole of Syria, the Gulf region, and in the countries surrounding Syria (excluding Turkey). In the past two decades, almost all blast furnaces across the globe use a charge burden consisting of various permutations and combinations of iron ore, sinter/pellets of iron-bearing materials as sources of iron depending on their availability, ease of operation, and economies of scale. But, sometimes due to the non-availability of iron ore fines, sintering, and pelletizing facilities, it becomes necessary to manage the charging burden only with iron ore as the sole source of iron. The present paper describes the efforts taken to achieve a low coke rate of 568 kgs/ton of hot metal (THM) during the recommissioning period of about 4 months (May to August 2018), wherein it produced about 56800 tons of hot metal from about 86100 tons of calibrated iron ore with peak production of 650 TPD against the designed capacity of 500 TPD in the mini blast furnace of ES located at Hassia, Syria.

Ladle Steel Slag in Activated Systems for Construction Use

The construction industry needs to reduce greenhouse gases, in which cement production is currently responsible for generating between 4% and 6% of the total CO2 released into the atmosphere. Similarly, many industries produce large amounts of solid waste, which often have low value-added applications or are directly taken to landfills, with consequent negative environmental impacts. One of these industries is the steel industry, which in 2016 generated 18.4 Mt of slag (melting and refining slag) among all European Union countries. In terms of refining steel slag (ladle or white slag), it is estimated that for each ton of steel, between 20 and 30 kg of slag is produced; that is, in 2016, more than 700,000 tons of white slag were generated. It is also known that this material has cementitious properties and can be used as a precursor in alkaline activation processes. Depending on the concentrations used of the activating agent, a higher or lower mechanical performance of the developed materials can be obtained. This work studied the alkali activation of a ladle slag used to manufacture mortars, subjecting them to an initial curing of 24 h at different temperatures (20, 40, and 70 °C). Sodium silicate and sodium hydroxide were used as activating agents, using percentages of Na2O between 5% and 10% to obtain an optimal dosage of the activator. The physical and mechanical properties of the mortars were evaluated at different ages of curing. In addition, monitoring was undertaken of linear shrinkage due to drying and the mineralogical changes due to activation and curing time.

Design and Engineering Application of Direct Mixing Lubrication System for Emulsion Pipeline in Secondary Cold Rolling Mill

With the benefit fierce competition in the steel industry market in recent years, double cold reduction products have been developed towards strength improvement and thickness reduction. The traditional cold-rolling lubrication process with a fixed flow rate and concentration cannot solve the problems which cover uncontrollable shape of strip product and the excessive consumption of lubricating oil. Moreover,based on the analysis of the traditional direct application lubrication system of double cold reduction, a set of design scheme suitable for the emulsion pipeline direct mixing lubrication system of double cold reduction unit is proposed.The design complete the selection of key components which include the static mixer and atomization nozzle selection, pump and oil pump design selection, pipeline design selection, flow type selection, pressure gauge selection, electronic control cabinet design selection and other aspects. Equipment of the emulsion pipeline direct mixing lubrication system of double cold reduction has been developed. Comparing with characteristics of the traditional direct aplication lubrication system, the emulsion pipeline direct mixing lubrication system was better applied to the production practice of a 1220 double cold reduction mill. The consumption of ton of steel was reduced by 9.6%. The rolling energy consumption and oil consumption comprehensive costs decreased by 10.7%, and the strip steel section thickness difference was reduced by 19.3%. In addition, the plate shape quality defect rate decreased by 25.6 %, otherwise creating a large economic benefit for the unit and promoting the application value.

Development and progress on hydrogen metallurgy

Hydrogen metallurgy is a technology that applies hydrogen instead of carbon as a reduction agent to reduce CO2 emission, and the use of hydrogen is beneficial to promoting the sustainable development of the steel industry. Hydrogen metallurgy has numerous applications, such as H2 reduction ironmaking in Japan, ULCORED and hydrogen-based steelmaking in Europe; hydrogen flash ironmaking technology in the US; HYBRIT in the Nordics; Midrex H2™ by Midrex Technologies, Inc. (United States); H2FUTURE by Voestalpine (Austria); and SAL-COS by Salzgitter AG (Germany). Hydrogen-rich blast furnaces (BFs) with COG injection are common in China. Running BFs have been industrially tested by AnSteel, XuSteel, and BenSteel. In a currently under construction pilot plant of a coal gasification-gas-based shaft furnace with an annual output of 10000 t direct reduction iron (DRI), a reducing gas composed of 57vol% H2 and 38vol% CO is prepared via the Ende method. The life cycle of the coal gasification—gas-based shaft furnace—electric furnace short process (30wt% DRI + 70wt% scrap) is assessed with 1 t of molten steel as a functional unit. This plant has a total energy consumption per ton of steel of 263.67 kg standard coal and a CO2 emission per ton of steel of 829.89 kg, which are superior to those of a traditional BF converter process. Considering domestic materials and fuels, hydrogen production and storage, and hydrogen reduction characteristics, we believe that a hydrogen-rich shaft furnace will be suitable in China. Hydrogen production and storage with an economic and large-scale industrialization will promote the further development of a full hydrogen shaft furnace.

EVALUATION OF THE USE OF BOF SLAGS FOR PREPARING SURFACE BY BLASTING

ABSTRACT: Approximately 400 million tons of steel slags are generated annually worldwide. For each ton of steel, between 130 and 100 kg of slags are produced depending on the process and the composition. Although efforts have been made to recycle this slag, a significant part still ends up in the landfill, Therefore, it is necessary to look for new alternatives of use. One of the possibilities is its use in the surface preparation of building materials surfaces. Blasting has many applications in different industries, but the associated environmental problems imply a low number of research works developed in this field. Although BF (Blast furnace) slag is regulated by the standard UNE-EN ISO 8504-2:2002, BOF (Basic Oxygen Furnace) slag is not. The aim of this paper is to analyze the possible application of these wastes as a substitute for traditional abrasives. The results show that it is possible to use BOF slag both for surface cleaning. However, a more in-depth investigation is needed. Key Words: circular economy; slags; civil engineering; abrasive blasting.

Strength Development in Bio Mineralised Steelslag Bricks using Micp Process

Steel slag annual production in India is about 12 million tonnes per annum. Steel slag is one of the industrial residue came out from steel industries. The amount of steel slag produced from different steel industries is 150-200kg per tonnes of steel produced These steel slag is dumped in land and pollute the environment. Paper mills produce the large amount of lime sludge is about 5 lakh tonnes per annum. These steel slag used as binder material and coarse aggregate also in different sieve sizes. These both steel slag and lime material contains large amount of calcium mineral compared than other waste materials. The conventional burnt clay brick manufacturing firing process develops the 750 million tonnes of co2 emissions per year. The Bio mineralised steel slag bricks developed by using these waste materials and bacillus bacteria. These microbes generates the calcium carbonate precipitation in the steel slag bricks. The strength development of these BMSS bricks were achieved by addition of NBU medium supply and carbonation process. The scanning electron microscope (SEM), mineralogical composition analysis, X-ray diffraction analysis, compressive strength and water absorption test are conducted to support the strength development in bio mineralised steel slag bricks.

Lost Material Stock in Buildings due to Sea Level Rise from Global Warming: The Case of Fiji Islands

This study developed a methodology to estimate the amount of construction material in coastal buildings which are lost due to climate change-induced sea level rise. The Republic of Fiji was chosen as a case study; sea level rise is based on predictions by the Intergovernmental Panel on Climate Change for the years 2050 and 2100. This study combines the concept of a geographic information system based digital inundation analysis with the concept of a material stock analysis. The findings show that about 4.5% of all existing buildings on Fiji will be inundated by 2050 because of an expected global sea level rise of 0.22 m (scenario 1) and 6.2% by 2100 for a sea level rise of 0.63 m (scenario 2). The number of buildings inundated by 2050 is equivalent to 40% of the average number of new constructed buildings in Fiji Islands in a single year. Overall, the amount of materials present in buildings which will be inundated by 2050 is 900,000 metric tons (815,650 metric tons of concrete, 52,100 metric tons of timber, and 31,680 metric tons of steel). By 2100, this amount is expected to grow to 1,151,000 metric tons (1,130,160 metric tons of concrete, 69,760 metric tons of timber, and 51,320 metric tons of steel). The results shall contribute in enhancing urban planning, climate change adaptation strategies, and the estimation of future demolition flows in small island developing states.

Rheological study and numerical analysis of high concentration iron ore slurry pipeline transportation

Steel making plants require around 3 times of minerals quantity as raw materials (fuel minerals also) to produce 1 ton of steel. Globally steel plants produce around 1800 million tons of steel per annum. This requires around 5.4 billion tons of minerals, which leads to generation of very high levels of emissions pollutants during surface transportation by road, rail and sea ways. To reduce the emission of pollutants in steel industry, hydraulic transportation technology is the solution for bulk movement of minerals through long distance underground slurry pipelines. This technology can move minerals over 33 million tons per annum for a distance of over 500 kms below the ground. The eco-friendly nature of this mineral’s movement has reduced Carbon, SOX, NOX, SPM emission levels by over 90% comparing to surface movement methods. It has also reduced energy consumption more than 90%. The movement of minerals through underground slurry pipelines contribute significantly for minerals conservation of our planet. The overall costs also reduced by over 70% through this technology for moving bulk quantities of minerals. The present study focused on rheological characteristics for hydraulic transportation of high concentration of iron ore slurry through pipeline using beneficiated iron ore from Odisha. The iron ores available in Odisha is different mineralogical characteristics in comparison with other ores available in India as well as global. Based on the rheological studies, available empirical mathematical model has been modified with respect to mineralogy of ore to predict viscosity of the slurry at different concentration.

Mechanical and sliding wear characterization of LD sludge filled hybrid composites

Linz-Donawitz Sludge (LD sludge) are the wastes generated during the production of steel in LD converter. Huge quantity of LD sludge is generated per tonne of steel produced. This waste can be gainfully used as a filler material in polymer matrix composites. In this work mechanical and sliding wear characterizations of aerial root of Banyan tree fiber filled epoxy-LD sludge composites have been evaluated. Six set of composite samples are fabricated by varying the fiber weight percentage by keeping fixed percentage (10 wt%) of LD sludge. Scanning electron microscopic analysis of fiber and composite is done to study the surface morphology of fiber, as well as to investigate the bonding between the matrix and reinforcement phases. Tensile strength, compressive strength, flexural strength and micro-hardness tests have been carried out as per ASTM standard. Sliding wear tests are carried out in a pin on disc apparatus as per ASTM G 99. Taguchi experimental design is adopted to carry out the sliding wear tests. It is observed that with increase in fiber content mechanical properties of the composites increases. From the Taguchi experimental design it is found that fiber content is the most predominant control factor affecting the wear rate of the composites.

Performance, Quality, and Control in Steel Logistics 4.0

In the steel industry, logistics is very often part of the value chain since storage processes and therefore cooling processes contribute to the product quality to a very larger degree. As a result, steel logistics is concerned with the storage and movement of – in our case – work in process (WIP) materials. Thousands of tons of steel are transported with cranes and heavy-duty vehicles and stored in stacks at large yards every day. The whole industry is under pressure to reduce costs, which strongly influences logistics operations. The efficiency of transport and storage processes is a crucial success factor and is challenged by highly dynamic processes and environments. In this article we focus on slab logistics with respect to logistics performance measurement, quality assurance, and operational control in the processes that directly follow the continuous caster. Closely related to this, we concentrate on selected aspects of the steel production value chain, especially concerning the logistics part. We evaluate the performance measurement and simultaneously show how quality assurance may be supported. Finally, methods from the domain of prescriptive analytics are employed to automate or support human resources in handling complex logistics operations.

Türkiye Demir Çelik Sektörü Rekabeti ve Endüstri 4.0

<p class="ql-align-justify">In Turkey in 2018 it produced about 37,3 million tons of steel in the world top ten steel producing countries 8th position. In 2018, exports of iron and steel products amounted to USD 11.5 billion and imports amounted to USD 18.4 billion. This corresponds to 11% of total exports and 8% of total imports. Iron and steel exports and imports are in the third place. In addition, Iron and Steel Sector, automotive, machinery manufacturing, construction, infrastructure, defense, and so on. is the basic industry for the industry. At the end of the study; most steel producing countries and Turkey top 10 iron and steel sector competitive advantages and disadvantages in the world are examined. Competitive advantage for the transition to Industry 4.0 has been studied, using technology and resources effectively to ensure global competitive advantage. “The Global Competitiveness Index 4.0” in Turkey with 62.1 points out of 100 points in 141 countries and ranks 61., China produces 928.3 million tons of 1,808.4 million tons of steel, 51% of which is the world's top steel producer, and the Global Competitiveness Index is ranked 28th with 73.9 points. India is ranked 2nd with 106.5 million tons of steel production and the Global Competitiveness Index is ranked 68th with 61.4 points. Japan ranks 3rd with 104.3 million tons of steel production and the Global Competitiveness Index is ranked 6th with 82.3 points. Ore, scrap, energy-importing Turkey, iron exceed 4.0 applications to provide a competitive advantage to industry in the steel industry will provide a competitive advantage.&nbsp;

КОМПЛЕКСНИЙ ТЕХНІКО-ЕКОНОМІЧНИЙ АНАЛІЗ ВПЛИВУ КОНСТРУКЦІЇ ВЕРХНІХ продувальних ПРИСТРОЇВ НА ОСНОВНІ ПОКАЗНИКИ ВИРОБНИЦТВА СТАЛі в кисневих конвертерах

У статті наведено результати розрахунково-аналітичної оцінки впливу конструкції верхнього продувального пристрою на основні техніко-економічні показники процесу виплавки сталі в кисневих конвертерах з донною подачею нейтрального газу. Проведення комплексної економічної оцінки базувалося на сумуванні відхилення відносних витрат виробництва, що пов’язані з забезпеченням виплавки залізовуглецевого напівпродукту (вартість основних шихтових матеріалів), без врахування вартості модернізації основного технологічного устаткування. За результатами проведених досліджень встановлено, що при використанні класичної конструкції верхньої кисневої фурми нижча теплота згоряння конвертерного газу складає 10 МДж/м3. У порівнянні з класичною конструкцією двоярусна, двоконтурна та триярусна фурми забезпечують зниження нижчої теплоти згоряння конвертерного газу на 8,5, 4,4 та 27,1 % відн. відповідно. При компенсації зниження теплоти згоряння димових газів за рахунок використання природного газу та врахування усіх основних параметрів технологічного процесу виплавки сталі економія складає 3,23 $ США / т сталі для двоконтурної, 6,81 $ США / т сталі – для двохярусної та 11,61 $ США / т сталі – для трьохярусної конструкції фурм у порівнянні з використанням класичної конструкції.

The ship recycling market in Brazil - The Amazon potential

Despite the considerable Brazilian coastline and vast water transportation cargo and passenger capacity, Brazil currently does not have a satisfactory amount of research aimed at ship recycling markets, especially in the Amazon region. This study aims to characterize this market in Brazil through research and data filtering related to national vessel fleets. Fleet data were obtained from the National Agency of Waterway Transportation (ANTAQ). Quantitative spatialization of the fleet was based on geostatistical distribution that show the current state of this market potential in the country. According to the ANTAQ database, in Brazil, there are approximately 3.8 million tons of steel that are suitable for dismantling, and this steel is distributed among 5319 vessels. There is no disposal plan for these vessels, which can result in environmental and social harm, and creates business opportunities. In this research, the great potential of this market was characterized to contribute, under socially and environmental optics, to the better organization of this sector in the country. Today 36% of existing vessels in the country have been operating for more than 20 years, and operation is concentrated in two major poles: the first is in the north, which is influenced by the city of Manaus (Amazon Region), and the second is in the state of Rio de Janeiro which is influenced by the offshore market. Based on the total amount of lightweight (LDT) and the number of vessels, both that could be potentially considered for decommissioning, this research shows the Brazilian market has global potentiality to attract and retain the ship recycling industry.

Utilization of Malaysia EAF slags for effective application in direct aqueous sequestration of carbon dioxide under ambient temperature

Iron and steel industries are among the contributors of CO2 emission in large volume into the atmosphere, causing detrimental effects to the environment and the ecosystem at large scale. These industries also generate solid wastes in the form of electric arc furnace (EAF) slag during operations which result in about 10–15% slag wastes per ton of steel produced. In this study, the EAF slags from an iron and steel-making factory in Klang, Malaysia was utilized for CO2 sequestration through direct aqueous mineral carbonation. According to the surface area analysis, the fresh EAF slag has a mesoporous structure, its elemental composition shows the presence of 20.91 wt.% of CaO that was used for the sequestration of CO2 through carbonation. The sequestration capacity was found to be 58.36 g CO2/kg of slag at ambient temperature in 3 h, with the liquid/solid (L/S) ratio of 5:1 and using <63μm particle size. Moreover, the shrinking core model (SCM) was used to analyze the solid-fluid reaction in a heterogeneous phase and the CO2 sequestration shows to be controlled by the product layer phase. The EAF slag is demonstrated to have the potential of CO2 sequestration at ambient temperature.

Life cycle water use and wastewater discharge of steel production based on material-energy-water flows: A case study in China

Abstract As a water-intensive industry, iron and steel production has caused serious water resource problems in China. This paper first proposes a material flow analysis-input-output model that considers water use factors and system boundaries for a life cycle water analysis. The life cycle water use and wastewater discharge inventories of different products are quantified, and water flow diagrams of life cycle water withdrawal, consumption and discharge for a steel plant in China are graphically mapped. The results show that the total life cycle water withdrawal, water consumption and water discharge per ton of steel in the case plant were 14.93 t, 5.90 t, and 9.23 t. The steelmaking process constituted the largest fraction, while the cold rolling processes constituted the smallest fraction. By analyzing the direct and indirect water and material-energy-water flow, the indirect water usage in energy and material flows was found to be more important to the water flow in the life cycle water use and discharge for steel production, especially for electricity. However, there were many differences among the subprocesses. In coking and sintering, the main factor was material flow; for ironmaking, water flow; for steelmaking, energy and water flows; and for hot rolling and cold rolling, energy flow.

Photovoltaic waste assessment: Forecasting and screening of emerging waste in Australia

Australia has to meet the challenges of End-of-Life treatment of photovoltaic modules in coming years due to rapid growth of photovoltaic capacity during the last decades. This paper contributes towards the sustainable management of decommissioned solar panels through the estimation of PV waste flow between the years 2031–2047 based on the actual installation of the PV modules from 2001 to 2018, and the provision of a forecasting model applying on four major scenarios to project the waste generated from 2048–2060. Assuming three forecasting schemes, and consistent annual-growth-rate of PV installation for each scenario, the future PV waste was quantified. Considering the PV installation from 2001 to 2018, the cumulative waste is estimated to be 0.8 million tonnes until 2047. The mainstream of the waste is estimated to be glass and aluminium with 541,209 and 116,483 tonnes respectively, followed by 8375 tonnes of copper and 71,329 tonnes of steel. The PV waste includes various valuable substances which, if appropriately recycled, can bring significant economic benefit. With regards to all PV penetration scenarios in the electricity generation market until 2030, Australia is estimated to face around 1–8 million tonnes of decommissioned PV until 2060. The recovery of the EoL PV raw materials can lead to value creation of nearly 1.2 billion dollars. These findings can shed light on the possibility of a circular economy and suggest an active contribution of all parties and a very well-planned coordinated approach prevent the potential environmental impacts and maximize resource efficiency.

Waste and material flow analysis in the end-of-life wind energy system

In the specific case of French onshore wind farms, waste management of these systems has become an important factor of the wind energy industry’s sustainability. The aim of this paper is to quantify wind turbine (WT) material wastes and flows across the Champagne-Ardenne (CA) region from 2002 to 2020. To do so, a material flow analysis (MFA) model was used. It included three maintenance strategies used for onshore wind turbines. Results show that more than 1 million tons of material will ultimately be generated at the EoL of CA wind farms. The main EoL materials are ferrous and non-ferrous metals, polymers, glass and concrete. The main EoL materials are ferrous and non-ferrous metals, polymers, glass and concrete. In this total, blades and composite EoL materials that need to be managed, account for more than 27,000 tons; there are 523,227 tons of steel and iron materials that need to be handled; 6617 tons of copper, and 28,179 tons of aluminum flows. Landfill concrete accounts for 734,230 tons. When the concrete in foundation is not considered, 73% of an average wind turbine can be recycled. With the first generation of WT reaching their EoL phase and taking into account that no dismantling or recycling facilities of WT components have emerged in the French territory, the potential of WT wastes available for treatment (recycle, incinerate, landfill etc.) is still increasing.

CO2 Utilization in the Ironmaking and Steelmaking Process

Study on the resource utilization of CO2 is important for the reduction of CO2 emissions to cope with global warming and bring a beneficial metallurgical effect. In this paper, research on CO2 utilization in the sintering, blast furnace, converter, secondary refining, continuous casting, and smelting processes of stainless steel in recent years in China is carried out. Based on the foreign and domestic research and application status, the feasibility and metallurgical effects of CO2 utilization in the ferrous metallurgy process are analyzed. New techniques are shown, such as (1) flue gas circulating sintering, (2) blowing CO2 through a blast furnace tuyere and using CO2 as a pulverized coal carrier gas, (3) top and bottom blowing of CO2 in the converter, (4) ladle furnace and electric arc furnace bottom blowing of CO2, (5) CO2 as a continuous casting shielding gas, (6) CO2 for stainless steel smelting, and (7) CO2 circulation combustion. The prospects of CO2 application in the ferrous metallurgy process are widespread, and the quantity of CO2 utilization is expected to be more than 100 kg per ton of steel, although the large-scale industrial utilization of CO2 emissions is just beginning. It will facilitate the progress of metallurgical technology effectively and promote the energy conservation of the metallurgical industry strongly.