The different activities described by the generic word recycling are presented along with an evaluation of the benefits of recycling in terms of natural resources or energy savings and reduction of Green House Gas emissions. A detailed analysis is presented of steel recycling, by-product recycling and end of life consumer goods recycling. The GHG emissions avoided thanks to sustainable steel recycling are evaluated in a long-term perspective. By-product recycling is also a major issue that has already been addressed with satisfactory results, as blast furnace slag valorization in the cement industry. This exemplifies the cross-business valorization of by-products with strong implications in terms of GHG emissions mitigation. Metal recovery is not yet as fully developed although a fairly satisfying solution is being implemented on the basis of the Rotary Hearth Furnace which separates iron from zinc with production of a DRI and concentration of zinc to a high enough level for direct use by zinc smelters. The future European regulations for consumer goods will require a high level of recyclability that will favour the design with metals instead of other materials such as plastics. Recycling is a complex, rich and fruitful concept that is popular today and will remain strong in the future. It functions both in the market economy and in the administrative world, with by-products moving around the various production shops within a business or between businesses of different crafts. Sustainable recycling is a significant and majority resource for the steel industry which, along with its partners in the recycling loop, has been a pioneer in the world of recycling.

For the promotion of zero emission society, the recycling of dust and sludge produced in the steel making process, leading to the recovery of valuable metals like Iron, Zinc, Nickel and Chromium, has highly attracted public attention. The Plant and Machinery Division of Nippon Steel Corporation has introduced the basic technologies of the rotary hearth furnace, DryIronTM Process, from Maumee Research & Engineering Inc. in the United States, and developed the process in order to recycle such dust and sludge effectively. In addition, the DryIronTM Process can also produce direct reduced iron from virgin iron ore and non-coking coal. In this paper, the features of the DryIronTM Process and the machine outline in Hikari Works of Nippon Steel Corporation are described.

A major investment programme is going on in the Sidmar steel plant. This programme will be described briefly. One of the investments was the modernization of the primary dedusting system of both BOF. The reason for this modification is twofold : reduction of the emissions through the flare stack and increase of the oxygen flow rate. This paper describes the existing equipment and all modifications made, the emission results and the very large influence on the BOF cycle time (reduction from more than 31 to 28 min only) leading to an important capacity increase of the BOF using a 1 out of 2 vessel operation.

In the series of conferences organized by VAI, the 2002 edition was devoted to steelmaking. The LD process was particularly at honour, at the occasion of its 50th anniversary. New developments at VAI in the area of upgrading and automation technologies for converter steelmaking were also presented, based on recent applications. Trends and developments in stainless steelmaking were finally reviewed and recently started-up plants were described.

Against the background of the several years lasting slump in the real price of stainless steels, different ways to reduce the production costs of these steels are analyzed. They consist in innovative technologies, some of which are already applied and others are still waiting for confirmation at the industrial scale. The emphasis is put on developments made by Voest-Alpine Industrieanlagenbau (VAI).

A new RH vacuum degassing equipment with a capacity of 2.4 Mt/year has been started up in this steel plant in 2001. This unit allows to decarburize liquid steel to a level of 30 ppm C for the production of ULC-grades, with short treatment times. The main components and features of this RH degasser are described and first metallugical results are presented.

The multiple versions of electromagnetic stirring in continuous casting are described. For long products, linear or rotational stirring appears confusing, but is clarified based on liquid steel flow pattern and metallurgical results. Rotational mould stirring is the predominant application in billet casting. For slabs, butterfly type single and double strand stirring and rotational mould stirring coexist with different metallurgical purposes. Also, the evolution to higher casting speeds has required a new type of mould stirring that combines accelerating and braking functions. The trend goes to multimode systems.

The development of a new type of stopper rod, Argorod, makes it possible to improve the steel quality during continuous casting. The main results that have been obtained concern the tightness of the joint : the new Argorod system, of second generation, has a better tightness, the assembling operation is simplified and more reliable; the optimization of the system for argon introduction: sized tube, more accurate adjustment of the couple argon flow rate / back pressure ; the accurate control of steel throughput: choice of the nozzle shape factor “material strength / stopper rod weight”: weight saving for the same or for a higher transverse strength.

If continuous casting mould slag has been the subject of many studies, this is not true for lubricating oils. Actually, there is a significant potential for progress through formulating these lubricants in order to make the industrial process more reliable and to improve both the operating conditions and the product quality. Specific laboratory tests have been carried out in order to understand the oil behaviour at high temperature. The lubrication mechanism has been further studied with the help of high-speed visualization of the phenomena occurring at the meniscus level during the industrial continuous casting of bar products. The results make it possible to better understand the mechanisms of oil lubrication and to precise the mechanisms of the formation of the first solidified steel shell along with the formation of solidification marks and solidification hooks. This should open the way for the development of new lubricants.

After the commissioning of its vacuum degasser (RH-KTB) in 1998, Companhia Siderúrgica de Tubarão (CST) started the development of slabs to be applied as high value added products, such as ultra-low carbon steel grades (ULC) for automotive applications. For this purpose, it was necessary to promote the development of a quality design system, encompassing all stages of steel manufacturing and slab casting at CST, as well as the steps of finishing rolling and coating. This paper describes the methodology for development of ULC steels at CST together with the company Sollac-Lorraine emphasizing the interchange of technical information aiming the continuous improvement. In this way, the results of the end product surface inspection are correlated with the technical parameters of steel production, including the quality events of steel refining and casting, as well as the slab conditioning.

From the viewpoint of a plate manufacturer, the status of steel plate quality for line pipe application is discussed. Technologies of the steel shop and the plate mill to create high class material are presented, as well as alloying and accelerated/intermediate cooling concepts. The levels of consistency that can be reached are illustrated on recent contracts. This includes sour gas resistant line pipe steels, applications for low temperatures and the extension of these features towards high strength grades.

The ends of food cans are submitted to higher and higher loads due to the persistent thickness reduction required by the canmakers. A finite element model supported by experimental tests shows that the physical performances of lightened food can ends are perceptibly improved by using an adapted design and the new steel grade, having increased mechanical properties and ductility, developed by Arcelor Packaging International.