STEEL & METALLURGY :: Abstract for September 2009 Issue

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Chains which offer a strength of min 3,000 kN New Transport Concepts for Conveying of Hot DRI into Electric Arc Furnaces
By Frank Reddemann, Aumund Fördertechnik GmbH

ABSTRACT
In the next years beyond 2010 world steel production is expected to grow at a yearly rate of about 8 per cent. In addition, the continuing globalization spreads technical innovations of manufacturing processes much faster in the future than in the past. However, the demand in some areas compared to the increase in steel production in the same or other areas will certainly cause various problems of global scale. Thus, the availability of raw materials will become more and more important and a stronger focus on transport cost and time will be necessary.
Today the German AUMUND Foerdertechnik, conveying and storage specialist, is able to provide a lot of references in the fields of iron making, primary aluminium industry, foundries and mining. AUMUND products are being applied successfully in the horizontal, inclined and vertical transport of bulk materials with extremely high temperatures. They support the process of storage and reclaiming, feeding and discharge of bulk materials. AUMUND´s core business is found in the field of conveying equipment, and during the last 10 years, some unique installations have been realized which have proven their worth in the transport of Hot DRI from the direct reduction stage to the further processing stage, the transport of HBI before and after the briquetting process, and the direct and continuous feeding of material into EAF with Hot DRI.
Environmental aspects become more and more important as well. Multiple processes and methods are worldwide at disposal today. Their choice is determined by the availability and cost of energy and raw materials.
If so far the effort for improving the processes has prevailed, lately the optimization of the material transport is gaining more and more importance. New materials demand new concepts and new specialized technical solutions.
Currently, in the global iron and steel making centers, considerable efforts and investments are either being planned or implemented. The hitherto publicized capacity increase, however, will hardly cover the expected demand. For this reason, primarily new and cost-efficient processes are required.
Under this aspect, India, Russia, the Middle East and South East Asia will play a special role in the next years. In Russia the large-scale open hearth furnaces which are still important in steel making, will have to be replaced in the foreseeable future. In view of the raw material situation, the new production processes applied will probably be the Direct Reduction and the Smelting Reduction technologies.

Duplexing with the Cokeless Melting Furnace
By Richard T. Taft, Cokeless Cupolas Limited, UK, Manufactured in India by The Wesman Engineering Co. Pvt .Ltd

ABSTRACT
Consider a melting process which uses half the energy compared with any other to produce a tonne of liquid iron. Add to this the low environmental impact the process has in the one third carbon dioxide emissions to the atmosphere compared with coke melting plus no sulphur emissions when melting with natural gas. Consider the metallurgical importance of a process that carries out a degree of refining in the melting operation compared with electric melting. Add to this the flexibility with regard to charge materials that a cupola possesses compared with other melting processes.
Finally, consider the advantage of the availability of a continuous supply of consistent high quality iron at low melting cost and surely this process must be of interest to forward looking foundrymen. The cokeless melting furnace in a duplex system fulfils all the above criteria.
It is well known that a cupola is an efficient melting unit due to its inherent design. Cold charge is added to the top of the cupola and liquid iron tapped from the bottom. Even the electricity industry acknowledges this aspect in that they are trying to develop an ‘electric cupola’. Once the iron is liquid the efficiency of the cupola drops rapidly as the tapping temperature is increased and this also applies to the cokeless melting furnace. It is also well known that once there is liquid metal electricity it is the most efficient way to superheat the metal, plus the bath of the electric furnace evens out any fluctuations in analysis and changes can easily be made if required.
Combine these two furnaces together and you have a very efficient melting process. It is difficult to operate a coke cupola consistently at low temperature as the coke is carrying out three functions of providing the fuel for melting, superheating the iron in the bed and also providing carbon. By separating these functions in the cokeless melting furnace the process can be controlled much more easily and more consistently. The fuel is burnt under controlled conditions within burners where precise measurement of air and fuel ensure ideal combustion. The degree of superheat and hence the tapping temperature is controlled by the depth of the bed of spheres and at the deliberately low temperatures of around 1350oC-1400oC adopted in the duplex process, a low consumption results so only small changes in the bed height occur, which can be controlled easily. Finally, the carbon required is added to the electric furnace to give precise control of analysis. The foundry has the best of both worlds, of an efficient cupola operation and metallurgical control with the electric furnace.

“Sarralle provides a one-stop shop for setting up a steel plant”
By Nirmalya Mukherjee, Editor

ABSTRACT
NM: Could you throw some light on Sarralle Equipment India and its activities in the area of EAF, LF, Automation and Process Control, Continuous Tapping and other Auxiliary equipments?
XE: Sarralle provides a one-stop shop for setting up a steel plant – with the experience, resources and ability to provide the entire range of equipment needed within steel plants.
Sarralle provides turn-key solutions for steel plants. It designs and supplies steel plant equipment such as:

Electric arc furnaces – from 25 tons to 250 tons capacity
Ladle furnaces – from 25 tons to 300 tons capacity
Fume exhaust systems
VD / VOD
RH Degassing
Continuous Casting Machine
Ingot Vacuum Casting degasser (VCD)
All auxiliaries for the steel making process
Control & Automation system (Level I & II) for all the equipment referred to above.

Sarralle approach to the CAPEX investment: Sarralle in his strategy is intending to make the most attractive package for the customer supplying the main components from its own manufacturing units in Spain & India, where the quality, delivery and competitive prices are assured to achieve a world class performance equipment keeping the budget affordable.
Post-commissioning support: Sarralle world wide recognise as per his close contact with the customers, providing a support not only on the project stage, all his units are capable to follow the founded strategy of close support to the customer in his maintenance activities, so all Sarralle units are willing to follow this relationship in a local channel for easy and faster interaction with the customers.
With manufacturing units located across three continents, and close to its customers, Sarralle is well positioned not only to provide world class installations, also to support its customer with all the necessary assistance and spare parts (with a very short response time)– very critical for efficient and productive operations.

TENOVA GROUP PROVIDES ADVANCED TECHNOLOGIES FOR THE METAL AND MINING INDUSTRY
By our news Bureau

ABSTRACT
Perhaps some readers are not yet familiar with the relatively new name of Tenova, but they are steadily making their presence known both in India and worldwide. Tenova, formerly known as Techint Technologies, is a world-wide supplier of advanced technologies, products and services for the metal and mining industries providing innovative integrated solutions. Combined process automation and metallurgical know-how enhance the value delivered to the customers. Tenova is committed further to develop its technology in the areas that mostly impact the future of the industries it serves: quality of the products delivered by the customers, energy saving and environmental safeguard. Tenova has operating companies in 5 continents and the Indian Sub-continent, a perfect mix of a global company with local roots. The network of companies allows Tenova to be always close to the customers providing them with technological support, rapid customer service and short time delivery.
India, which is set to become the world’s second steel producer after China, is a very interesting market for Tenova; in fact Tenova has several local Indian Companies such as Multiform Machinery , headquartered in Mumbai, where its production facilities are located, with a workforce of 80, one of India’s main suppliers of cold rolling mills and strip processing lines; LOI Wesman, a company of LOI Italimpianti located in Calcutta; Hypertherm, a Company of LOI Italimpianti, located in Mumbai and TAKRAF India, specialized in mining and bulk handling equipment, located in Chennai.
The Tenova Group is part of the Techint Organization, which also includes Tenaris (worldwide producers and suppliers of steel pipe), and Ternium (flat and long steel products producers). The following companies form part of the Tenova Group

Tenova LOI-Italimpianti Tracking Simulator: High Flexibility for RHF production analysis
By Toni Rossi, Massimiliano Fantuzzi, Vittorio Laviosa
Tenova LOI-Italimpianti Genova, Italy

ABSTRACT
RHFs (Roller Hearth Furnaces) connect the casting section to the rolling area of a CSP plant. Thin slabs from the casting lines are heated in the RHF up to the rolling temperature (1050-1200°C). For complying such a task a relatively short time is necessary (compared to the reheating time of a WBF fed with cold charge). The overall length of a RHF is however longer than the minimum one necessary for the heating only. An additional furnace length corresponding to some slabs to be recovered in a soaking zone is considered after the heating zone. In this way, while the continuous casting machines are feeding the RHF with thin slabs, it is possible to perform the on-line maintenance operation at the finishing mill (rolls change). The empty space inside the RHF available for recovering slabs during the mill stop (or the corresponding time available for filling up the furnace) is normally called “buffer” or “buffer-time”. The buffer depends on the casting speed (which can be adjusted only with small variations) and the rolling speed. The target is to minimize the buffer for all the possible productions in terms of: thin slabs lengths, charging temperature, casting speed, rolling speed. This condition corresponds to the minimum RHF length for a required production mix while avoiding continuous caster slow-down or even to scrap slabs due to the furnace full.
RHFs layouts >> The basic plant layout consists of one continuous casting line connected to the finishing mill through the RHF. In order to increase the productivity a plant layout with two continuous casting lines is adopted. In this case the productivity is not simply doubled due to the fact that it is necessary to transfer the slabs from the line not directly connected to the mill to the one connected. Two solutions are generally considered: The first is with shuttle ferries (figure 1).