Alternative Reducing Agents in Metallurgical Processes: Devolatilization of Shredder Residue Materials
Number of Authors: 3
2016 (English)In: Journal of Sustainable metallurgy, ISSN 2199-3823 (print), 2199-3831 (online)Article in journal (Refereed) Epub ahead of print
Plastic-containing shredder residue material has the potential to be used as an alternative reducing agent in nonferrous bath smelting processes. This would lead to not only decreased dependency on primary sources such as coal or coke but also to an increase in the efficiency of utilization of secondary sources. This calls for systematic scientific investigations, wherein these secondary sources are compared with primary sources with respect to devolatilization characteristics, combustion characteristics, reactivity, etc. As a first step, in this paper, devolatilization characteristics of plastic-containing shredder residue material (SRM) are compared to those of coal using thermogravimetric analysis. Proximate analysis has shown that SRM mainly decomposes by release of volatiles, while coal shows high fixed carbon content, which is reported to contribute to reduction reactions. To study the reduction potential of the evolved materials, composition of evolved off-gas was continuously monitored using quadrupole mass spectroscopy. The composition of volatiles shows H2, CO, and hydrocarbons which are known to have reduction potential. Therefore, it is essential that SRM would be used in a process that could utilize the evolved volatiles for reduction. Furthermore, to understand the potentials of different plastic materials as reducing agents, the devolatilization mechanisms and volatile composition of three common plastics, namely, polyethylene, polyurethane, and polyvinylchloride and their mixtures have been studied. The results show the interaction between the plastics within the binary and ternary mixtures. Similar phenomena may occur during devolatilization of SRM, which contains different type of plastics.
Place, publisher, year, edition, pages
Metallurgy and Metallic Materials
Research subject Process Metallurgy
IdentifiersURN: urn:nbn:se:ltu:diva-60056DOI: 10.1007/s40831-016-0094-0OAI: oai:DiVA.org:ltu-60056DiVA: diva2:1043707