Yield is not only a measure of our technological skills and mastering of the complex process involved from raw material to finished processes, but it further impacts our business and environmental performance. This is particularly true after the manifold increases in raw material and energy costs and mounting environmental pressure in nearly all areas of the world. Therefore, it is essential to be in control of yield and improve performance where possible.
This study is not meant to be a rigorous academic analysis of yield and yield influences but to be a guide for the practitioner to assess local situation and come up with local solution. Given the variety of steel plant layouts, products and markets served, plus the diversity of raw materials and other inputs to the steel making process, one single solution or suggestion can not be expected. Rather, every individual steel company will have to assess its own situation and come up with its own solution and strategies. This study is meant to be helpful in devising these strategies by providing an overview of general relationships and trends in the industry as well as showing good practices.
The study is based primarily on an evaluation of the industry, obtained through a questionnaire distributed amongst member companies in 2004 and 2005. In addition, experts from the member companies came to assess the results and to provide their own insight and expertise.
An important part of the project was the definition of yield for individual sections. To achieve globally comparable data this study did not ask for actual yield numbers but information and data from which the project group calculated yield numbers based on a universal definition, as given before every evaluation section in this report.
The three main objectives are:
- Benchmark current standing with respect to yield of ferrous units throughout the process chain
- Identify recent developments since last yield study (1992)
- Identify recent and expected future trends and developments.
The objective of identifying trends and expected developments was seen as a particularly important addition to the scope of the project, which was not covered in the last project. Since this is closely linked to specific conditions, it was not possible to identify universal trends. Still, it can be argued that yield will remain an important topic which is increasingly addressed not just from a technology viewpoint but also with a more holistic approach to the whole operating framework.
*The source of this article is from the report on "Yield Improvement in the Steel Industry" published by the World Steel Association in 2009. The Report covers all areas of the Steel Industry from iron making to rolling mill. For this article, we only pick EAF, Secondary Metallurgy and Continuous Casting.
Source: SEAISI, WorldSteel