Responsible
- Christoph Meyer
Initial Situation and Problem
Iron and steel slags are essential by-products of iron and steel production. In 2014, the annual production of 42.6 million tons of crude steel entailed the output of 13.1 million tons of iron and steel slags in Germany. Iron and steel slags accrue inevitably and vary in amount and material composition according to the respective procedural setting. These characteristics allow for diverse utilization options. For instance, iron and steel slags are used for producing road construction material, cement or fertilizer.
The possibility to use a specific utilization option is subject to technical, economical and legal characteristics. From a steel manufacturer’s point of view, the concurrence of these characteristics poses the question how to utilize iron and steel slags in an economically reasonable way. This evokes versatile challenges: On the one hand designing and using a utilization option requires long-term commitments such as investments and/or service contracts. On the other hand short-term changes of utilization settings such as legal alterations must be taken into account.
At present a draft of a decree prospects the introduction of new critical values for the usage of substitute construction materials. It is anticipated that these new critical values will ban certain iron and steel slags from being used as road construction materials. In order to prevent a possible disposal of iron and steel slags on account of new critical values alternative utilization options are to be considered. An approach allowing to determine the relative and absolute advantages of specific utilization options while taking into account all relevant characteristics is not known.
Objective and Approach
The objective of the project consists in developing an approach using techno-economical analysis that allows an evaluation of present and possible future utilization options for iron and steel slags. The project is divided in six work packages:
- Assessment and classification of relevant energy and material flows concerning iron and steel slags.
- Modeling of relevant generation and utilization processes based on the former assessment and classification
- Assessment and classification of relevant costs pertaining to generation and utilization processes
- Model conception and implementation for techno-economical analysis and evaluation of utilization options for iron and steel slags
- Conception of scenarios for the future development of relevant energy and material flows
- Recommendations derived from scenario analysis by means of the techno-economical model