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A new ironmaking process suitable for the supply of minimills will make its debut in Brazil before the close of 2007. The Tecnored process provides a low CapEx and environmentally-friendly method of producing iron units by treating ore fines and iron bearing wastes blended with carbon fines and pellatised.
In recent years various authors have discussed the remarkable opportunities increasingly becoming available with the use of alternate iron units in the Electric Arc Furnace (EAF) in minimills, especially as the availability of premium quality scrap has become more problematic due to both unprecedented levels of worldwide crude steel production and minimills moving towards the production of high end products.
In the authors' opinion, the ultimate targets of the use of alternate iron-units by minimills are:
- To increase plant productivity;
- To improve both quality and cost reduction;
- To improve overall charge supply to the plant;
- To allow the steelmakers to add value without equivalent added cost
With these central objectives in mind liquid hot-metal, among all other possible scrap substitutes, has proven to be by far the best. This is normally the conclusion when a 'value in use' analysis of hot-metal against other alternate iron units is performed.
At the same time the evolution of steel shop technology has also shifted rapidly to accommodate new charge mixes. Indeed, from 100% low-C scrap charge without liquid heels that have characterised many EÀF shops in the past 20 years, the charge mix of a modern EAF steel shop has constantly evolved rapidly towards the use of high-C charges and liquid heel practices.
In this scenario, processes like Tecnored can lead to new opportunities in the value chain of the steel industry.
TECNORED PROCESS
Tecnored coal based ironmaking is a quantum leap technology, patented worldwide, that uses a moving bed shaft furnace (Fig 1) served by classical peripherals and featured by two innovations:
* The side feeders of solid fuels that prevent the Boudouard reaction (C+ CO2- 2CO with heat absorbed) in the upper shaft hence saving en erg);
* The internal postcombustion of the upstream CO gases that provides additional energy for the rapid reduction of the selfreducing agglomerates in the reduction zone of the furnace.
Tecnored produces blast-furnace type high carbon molten...