EUROPEAN STEEL TECHNOLOGY AND APPLICATION DAYS 2017 - ESTAD 2017

The intensive use of automation solutions, process models as well as expert systems is well established in converter steelmaking. and It is widely recognized that automated procedures have a positive influence on productivity, product quality and operational safety. The combination of existing technologies, new support systems and the beneficial use of information management tools empower the...

BOF bottom gas purging has been established as inevitable technology for high quality demands at decreasing conversion cost levels. The trend for applying raw materials with higher variations in phosphorus at the same or increasing product quality levels increases the need for reliable, save and long-term available inert gas purging. Higher converter lifetime at decreasing converter refractory...

This work was a continuous development and multidisciplinary. Through the blowing process survey data and process parameters being were conducted developments , enhancements and adjustments at lance tip hot face parameters with Slagless technology , as well as blow process parameters, reestablishment system " autopilot " blow and mitigating actions for slopping. The main results are Increased...

BOF, due to operational conditions and location, suffer variations in the parameters whose effects on the liquid bath are usually neglected. The present paper investigated mainly two aspects: inner BOF pressure and oxygen temperature in the stagnant reservoir. The results shown that oxygen temperature changes properties like density and velocity but has small influence on jet penetration. The...

Numerical flow simulations have constantly evolved in the last decades and nowadays play an important role in the development of modern converters. The flow inside the converter is highly complex and comprises a whole lot of physical phenomena like supersonic flow, chemical reactions, heat transfer and the flow of gas bubbles in the liquid melt. Due to numerical reasons, not all flow processes...

Oxygen blowing is the main operation in the steel refining process in BOF (Basic Oxigen Furnance) steelmaking. This blow is made by an oxygen injection lance through supersonic nozzles, which must be designed for the specific operating conditions, such as flow and oxygen pressures, height in relation to the metal bath, lance height, etc.. Bad design of these nozzles directly influences the...

In order to enhance the reaction rate between the slag and the metal, the formation of metal droplets in the slag phase (metal emulsion) is an effective measure. In this paper, the formation behavior of metal droplets by the bubble rupture of the gas injected into the metal phase was investigated. To extract the metal droplets, the water soluble chloride (KCl-LiCl-NaCl) and oxide (Na2B4O7)...

In the present work, an analysis of geometric parameters of tip nozzles in operation was developed and extrapolations for futures situations were proposed. The main trigonometric relationships to evaluate the possibility of jet coalescence were determined. The results showed that the Primary Circle Diameter (PCD) is not affected only by the geometry of the nozzle, tips with up to 04 (four)...

Environmental protection has become more important in the iron and steel making industry during the last few decades. Stricter environmental protection measures are now required to comply with regulations set by government agencies. Dry dedusting systems (DDS) represent the latest technology for cleaning the primary gas of basic oxygen furnaces (BOF). Due to increasing economic pressure on the...

The primary control tool of the BOF process lies on the adjustment of the oxygen blow parameters. The best process conditions involve several variables, like oxygen flow rate, distance bath lance (DBL), number of holes for the oxygen blow, among other factors. Through a visual inspection of the jet penetration and the volume of stagnant zones, the behavior of each configuration tested was...

Treatment of hot metal in a Basic Oxygen Furnace (BOF) is a highly exothermic, complex, oxidising-refining process in order to remove hot metal impurities (mainly carbon and phosphorus) from iron and to achieve an optimal end temperature for further treatment of the crude steel. End-point control of the BOF process is in general based on static charge calculations and observation of...

The technological knowledge of BOF process represents an important key to improve metallurgical results. In a challenging and competitive market, operational stability and innovation are necessary to achieve excellent quality and suitable costs. In order to study the combined blowing (top and bottom blow) through cold physical model, in similarity with thyssenkrupp 330 tons converter, visual...

The continuous increase of the production steel in the last decades, caused the adjusted in steel plants in adapt in the new demand the acquiring manufactured steel. This study aimed to analyze the reactors ranging 6-350 tons of steel cast correlated their dimensional parameters and with the help of the tool data extrapolation, to propose the furnace of 800 tons. Ultimately, were checked the...

Sustainable steel making comprises the efficient utilization of the byproducts generated during the technological process. The general byproduct generated during the converter steelmaking process is the off gas, which contains a huge amount of physical –temperature and chemical – CO and H2 energy. The efficient utilization of both types of energy is the target of this research. The amount of...

For cleaning of primary gases from BOF-process, the well approved wet scrubbing technology is worldwide the most applied technology. Most of these installations are running for more than 20-30 years. They were originally designed for compliance with environmental regulations much less stringent and complex than nowadays. The revamp, upgrade and retrofit of these systems to fulfil actual...

ArcelorMittal USA Indiana Harbor plant is making large quantity of high Al TRIP and DP grades to meet the needs from automobile industry for high strength and high deformability steel products. During steelmaking process of these high Al TRIP and Dual Phase steel grades, it has been observed that the nitrogen behaves very differently from regular Al-killed steels. Nitrogen will drop along the...

Since the development of basic oxygen furnace (BOF) the modelling of the process reflects a huge field of activity due to the accelerated increase of BOF steel plants. The optimization of the BOF process is focussed, amongst others, also on the thermodynamic and kinetic modelling. With the program MatLab® a new BOF model has been developed. One of the main topics is the description of the...

Noticed the strong national and international industrial activity, more specifically concerning the steel production and the model of oxygen converter adopted on the different types of primary refining process, this work applies to relevant models, revaluating since the more rudimentary techniques till the current technologies. Then they will present the methods in which resulted the study of...

To further reduce process times and increase availability at the LD converters in the high-performance steel mill of voestalpine Stahl GmbH in Linz, Austria, the old hydraulic sublance manipulators were replaced with three new robotic sublance systems by Primetals Technologies Austria GmbH. The main criteria for the project were: high availability of >98 %, short cycle times in sublance-probe...

The aim of the BOF (Basic Oxigen Furnace) process is to convert carbon-rich liquid hot metal from the blast furnace to low-carbon steel, which may be refined in the secondary steelmaking shop. Fluxes are needed in this process to remove impurities from the liquid hot metal and form an appropriate slag which could be easily separated from the steel. These fluxes could require low melting points...

At thyssenkruppCSA, a positive heat balance at BOF process is faced, mainly because of low utilization of scrap and plant design. A singular logistic concept for hot metal transport between blast furnace and steel plant was stablished to optimize handling, transport and energy. An average addition of 75kg of iron ore pellets/t steel is necessary for the BOF-340t heat balance. In order to...

In this hard days for Brazil steel market, all steel shops want to achieve the same goal, work with : productivity, low costs and high performance. In this scenario the Slagless technology (which is applied into BOF converter) was important to reach this targets.After use has been reduced the number of times of nozzle exchange in more than 04 times. Was reduced too, the time to remove lance...

The application of post-combustion to avoid skull formation on BOF lances was tested in industrial trials. The main findings are that no negative impact on the metallurgical targets (i.e. carbon, temperature and phosphorus at end of blow as well as iron–oxide in the slag) could be observed. The technology is capable of avoiding the buildup of lance skull and consequently increasing the average...

There is one challenge known to all metallurgists: how much of each ferroalloy to add during steelmaking process in order to ensure the required chemistry of the steel at the lowest possible cost. As ferroalloys participate in numerous chemical reactions, the final absorption of the added elements depends on many factors, which measurements are rough or even unknown. The decision on the exact...