The climate change challenge and transitions for radical changes in the European steel industry

This paper presents ideas pertaining to transitions that are envisaged in the steel industry from Cleaner Production (CP) to Systems Innovation. Limits of the socio-technical system and the climate change challenge will induce changes in the production, distribution and consumption patterns of steel and other materials. Insights from industrial economics and evolutionary theory on innovation for sustainable development are needed to assess the rationale behind the adoption and diffusion of new breakthrough technologies named Ultra Low CO2 Steel making (ULCOS). Evolution in material consumption patterns deserves a special research agenda which focuses upon the long term evolution of the consuming sectors as major changes in the infrastructure and products that support our many energy dependent services (mobility, shelter, heat, light, etc.) are expected. These changes will be significantly amplified by greenhouse gas emission constraints

Exergy-based efficiency analysis of pyrometallurgical processes

Exergy-based efficiency analysis provides a powerful tool for optimizing industrial processes. In this article, the use of this technique for pyrometallurgical applications is explored in four steps. First, the exergy concept is introduced, the outline of exergy calculations is presented, and the role of a reference state is discussed. Second, it is shown that an unambiguous exergy calculation for pyrometallurgical streams with a complex, unknown phase composition is not straightforward. Hence, a practical methodology is proposed in which a suitable phase-based stream description is estimated prior to the actual exergy calculation. For this, the equilibrium phase composition is calculated, whereas all known stream properties are incorporated as boundary conditions. Third, the proposed methodology is validated by recalculating literature results. This reveals significant deviations for exergy values of the same pyrometallurgical streams. Our results are probably more accurate because of the incorporation of additional phase-related information. And fourth, a full analysis of a zinc-recycling process is presented. In a base case scenario, the total exergetic efficiency turns out to be only 1.2 pct. Based on this result, different process modifications are suggested and evaluated quantitatively. We find that significant efficiency gains are possible