Within the steelmaking industry, a large amount of zinc-bearing waste is produced which cannot be effectively treated through integrated steel mills. Concurrently, zinc smelters generate waste residues containing significant amounts of iron and zinc which are stored or landfilled. The zinc concentration of iron and steelmaking residues inhibits its recycling to the blast furnace but is insufficient to be sent directly to the zinc producers. Consequently, a means of up-concentration is required. The pilot HIsarna ironmaking furnace has shown potential for processing secondary iron-bearing resources. Furthermore, zinc can be concentrated in the off-gas flue dust, providing an enriched input for zinc smelters. The potential recyclability of blast furnace (BF) and basic oxygen furnace (BOF) dust and ‘goethite’ residue from the zinc industry has been studied. The input materials have been comprehensively characterized and their reduction–vaporization behavior, has been investigated. Individual samples were tested at temperatures of up to 1300 °C. Here, it was shown that minimal reduction of iron and volatilization of zinc occurred in the goethite and BOF samples. Conversely, even at 1000 °C, the BF dust showed complete reduction of iron and removal of zinc within 30 min. This was due to its high carbon content (40 wt%) which can act as a reductant. Consequently, mixtures of BOF dust and goethite with BF dust were studied. It has been shown that mixtures of 30:70 BF dust to goethite and 20:80 BF dust to BOF dust are suitable for recovering zinc to the gas phase and fully reducing the contained iron. Graphical Abstract: [Figure not available: see fulltext.] ... Read more

Outpaced by the speed of digital innovation in the private sector, governments are looking for new approaches to public service innovation. Drawing on three complementary innovation theories - open innovation, recombinant innovation and co-creation - this paper presents a prototype that is designed to enhance the online innovation journey for public services. The main strategy explored is that of online public-service co-creation, allowing innovators to combine online and offline efforts. The outcome of this research is a prototype of an online co-creation tool. The tool is consumed via a web-portal that includes an overview of ongoing experiments, tools, labs data sets and digital building blocks. This paper contributes by presenting the requirements and lessons learned when developing a co-creation tool for innovation in public service design. While the proposed co-creation tool is expected to enhance and speed up online cocreation efforts, findings indicate that innovators from the public and private sector still need to learn how to combine online and offline co-creation efforts. The added value expected from the online tool is that it should provide an up to date oversight of digital building blocks, innovation methods and labs. Interviews with prospective users suggest that this oversight is needed to jumpstart the first step of the innovation journey. Development of a digital sandbox - a shared online experimentation environment - is considered to be an important next step for innovation in public service design. ... Read more