Glass recovery and production of manufactured aggregate from MSWI bottom ashes from fluidized bed and grate incineration by means of enhanced treatment

Julia Mühl; Stefan Skutan; Gerhard Stockinger; Dominik Blasenbauer; Jakob Lederer

doi:10.1016/j.wasman.2023.05.048

Glass recovery and production of manufactured aggregate from MSWI bottom ashes from fluidized bed and grate incineration by means of enhanced treatment

Waste Manag. 2023 Aug 1:168:321-333. doi: 10.1016/j.wasman.2023.05.048. Epub 2023 Jun 17.

Authors

Julia Mühl¹, Stefan Skutan², Gerhard Stockinger³, Dominik Blasenbauer⁴, Jakob Lederer⁴

Affiliations

¹ Christian Doppler Laboratory for a Recycling-based Circular Economy, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Getreidemarkt 9/166, 1060 Vienna, Austria. Electronic address: julia.muehl@tuwien.ac.at.
² Christian Doppler Laboratory for a Recycling-based Circular Economy, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Getreidemarkt 9/166, 1060 Vienna, Austria; Ingenieurbüro Stefan Skutan e.U., Fritz-Weigl-Gasse 1a, 3423 St. Andrä-Wördern, Austria.
³ Brantner Österreich GmbH, Dr.-Franz-Wilhelm-Straße 2a, 3500 Krems an der Donau, Austria.
⁴ Christian Doppler Laboratory for a Recycling-based Circular Economy, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Getreidemarkt 9/166, 1060 Vienna, Austria.

PMID: 37336140
DOI: 10.1016/j.wasman.2023.05.048

Abstract

Enhanced treatment of incineration bottom ashes (IBA) from municipal solid waste incineration can contribute to a circular economy since not only metals can be recovered but also glass for recycling. Moreover, the remaining mineral fraction can be utilized in concrete as manufactured aggregate. To evaluate the effects of an enhanced treatment, three IBAs from fluidized bed combustion (FB-IBAs) and three grate incineration bottom ashes (G-IBAs) were standardly treated in a jig and further processed on a pilot scale, including improved metal recovery and sensor-based glass separation. The removed glass fractions were weighed and their composition was assessed by means of manual sorting. The manufactured aggregate was also sorted manually and its total and leachate contents were determined before and after aging. Results showed general differences between FB-IBAs and G-IBAs. For G-IBAs, higher contents of heavy metals and residual metal pieces were determined, while the share of glass removed was low compared to FB-IBA. The treated mineral fractions from G-IBA contained more mineral agglomerates, whereas FB-IBAs contained more glass. However, the glass-fractions removed from FB-IBAs need further treatment to be accepted in glass recycling. Austrian limit values for utilization in concrete were met by all manufactured aggregates produced from FB-IBA, but only by one from G-IBA. Overall, the enhanced treatment in the study performed well compared to the literature. Nevertheless, further investigations are necessary to improve the recyclability of the recovered glass fractions and to determine the technical suitability of manufactured aggregates produced from IBAs.

Keywords: Circular economy; Concrete production; Fluidized bed combustion; Glass recycling; Grate incineration; Incineration bottom ash; Manufactured aggregate; Municipal solid waste incineration; Waste glass.

MeSH terms

Coal Ash
Incineration*
Metals, Heavy* / analysis
Recycling
Solid Waste / analysis

Substances

Coal Ash
Metals, Heavy
Solid Waste