Life Cycle Assessment Model for the Use of Alternative Resources in Ironmaking

Abstract

The iron and steel industry represents an important case for industrial ecology due to its ability to accept waste-derived inputs and due to the generation of useful by-products. With the objective of supporting environmentally conscious decisions regarding resource use and waste management, a life cycle assessment (LCA) tool for ironmaking was developed. The tool combines mass flow-based process models with an LCA database to assess the use of alternative resources in ironmaking, considering various process configurations. The article contains a description of the tool and a case study illustrating two areas of application. In the first part of the case study, an inventory analysis focused on the effects of feedstock recycling of waste plastics in ironmaking on heavy metal distribution is presented. It is demonstrated how uncertainties in input heavy metal concentrations and mass transfer can be incorporated into the model to predict the heavy metal loads in the process outputs. In the second part, the substitution of coke with a range of alternative reducing agents are assessed with regard to impact on climate change and fossil resource depletion. It was found that the use of sustainably sourced charcoal and waste-derived reducing agents is beneficial both with respect to the impact on climate change and fossil resource depletion at the respective calculated coke replacement ratio, whereas the results for heavy oil, coke oven gas, and raw tar indicate that trade-offs between impact categories occur. The results also highlight the importance of considering the avoided impacts of alternative treatments for waste-derived resources. Keywords:blast furnace industrial ecology life cycle assessment (LCA) mass flow model sustainable resource use waste management Supporting information is available on the JIE Web site

Influence of waste plastic utilisation in blast furnace on heavy metal emissions

“…According to previous works Pilz and Bürgler, 2007;Vadenbo et al, 2013), that applied transfer coefficients to assess emissions, a clear dependency between emission levels of heavy metals and their respective inputs into the blast furnace should be expected.…”

“…To our knowledge, Vadenbo et al (2013), Pilz and Bürgler (2007), and Bürgler et al (2007) were the only ones who accounted for the additional input of heavy metals into the blast furnace and the emissions induced when utilising waste plastics. Vadenbo et al (2013) conducted a detailed LCA to investigate the effects on heavy metal distribution of waste plastics utilised in ironmaking. For their LCA model, they assumed a linear relationship between the input of heavy metals and the resulting emission levels based on fixed transfer coefficients (TC) for the blast furnace.…”

“…Special emphasis is given to testing the so far commonly used assumption of a linear relationship (fixed transfer coefficients) between input and output flows of heavy metals , Pilz and Bürgler (2007), Vadenbo et al (2013)). As an alternative to fixed transfer coefficients, the usage of so-called emission factors (EF) is evaluated.…”

“…To assess the environmental impact of the steel industry Life Cycle Assessment (LCA) (Burchart-Korol, 2013;Norgate et al, 2007;Vadenbo et al, 2013) have been carried out and extensive Life Cycle Inventory (LCI) data has been collected (Bieda, 2012;Huang et al, 2010;Jing et al, 2014). Spengler et al (1998) developed a Multi Criteria Decision Making (MCDM) concept to support environmental assessment of recycling measures in the iron and steel industry.…”

An Evaluation of Input–Output Value for Sustainability in a Chinese Steel Production System Based on Emergy Analysis

“…In addition to emergy analysis, other eco-economic assessments have also been tried to evaluate the sustainability of steel production. For example, the life cycle assessment method, which mainly concerns the environmental impact of goods and services, has been used at different scales [31][32][33][34]. Although each method has its own advantages and disadvantages, it may be more scientific and informative to combine several eco-economic assessments with emergy analysis.…”