Explorative Multiple-Case Research on the Scrap-Based Steel Slag Value Chain: Opportunities for Circular Economy

Mohammadtaghi Falsafi,Rosanna Fornasiero

doi:10.3390/su14042284

Abstract

This paper analyses the scrap-based steel slag from the electric arc furnace and secondary metallurgy and proposes a framework for valorising its value chain. Toward this aim, the role of slag features, technological advancements for the treatment of slag, applications, legislation, and their value chain in the circular economy and industrial symbiosis opportunities are discussed within the proposed framework. By interviewing a group of Italian steelmakers, accounting for around 30% of Italian scrap-based steel volume, we analyse various value chain key factors, namely, technology, legislation, production volume, and economic aspects. Consequently, we assess the as-is situation of the sector and elaborate on the challenges and expectations for the future in terms of collaboration frameworks. The results show how vertical (by internal treatment) and horizontal integrations (by collaborating with other potential industries) support decisions on material flow and facilitate circularity in sharing this kind of material. The most influential enabler in a vertical integration is the economic aspect, while in the horizontal integration the enablers are the market and technology. We also address the importance of raw-material self-sufficiency through analysing closed-loop supply chains and collaborative supply-chain networks.

Highlights

Around 26% of the worldwide total of crude steel is produced in electric furnaces [1].Among the electric furnace production methods, the scrap-based route has attracted significant attention in recent years as the most sustainable route
This paper aims to explore the opportunities for slag valorisation in Italy through multiple-case research
The main difference between the companies is guided by the legislation for slag use of the region where they are located: while SMs 3 and 4 are located in a region where legislation allows for the use of slag in some sectors, the regional legislation for SMs 1, 2, and 5 are stricter

Summary

Introduction

Among the electric furnace production methods, the scrap-based route has attracted significant attention in recent years as the most sustainable route. The principal reason for this attention is the high fossil fuel consumption when coal is used in iron-based steel production. Coal consumption causes high levels of CO2 emissions, accounting for 10 times as much as scrap-based production. Many steelmakers (SMs) will have to recalibrate iron-based steel production as a strategic decision (e.g., [4]). These decisions are part of the carbon direct avoidance of the EU steel industry’s technological pathways [5]

Objectives

Methods

Results

Conclusion