Recycling of polystyrene-based external thermal insulation composite systems – Application of combined mechanical and chemical recycling. (1st August 2022)

• Record Type: Journal Article
• Authors: Netsch, Niklas; Simons, Martin; Feil, Alexander; Leibold, Hans; Richter, Frank; Slama, Julia; Yogish, Savina Padumane; Greiff, Kathrin; Stapf, Dieter
• Is Part Of: Waste management. Volume 150(2022)
• Page Start: 141
• Page End: 150
• Publication Date: 2022-08-01
• Subjects: Plastics recycling -- Circular economy -- ETICS -- Pyrolysis -- Gasification; ETICS External thermal insulation composite system -- EPS Expanded polystyrene -- EU European Union -- XPS Extruded polystyrene -- HBCD Hexabromocyclododecane -- GC-FID Gas chromatography-flame ionization detector -- GC-TCD Gas chromatography-thermal conductivity detector -- PS Polystyrene; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2022.07.001
• Languages: English
• ISSNs: 0956-053X

Abstract

Abstract: The material recycling of complex waste streams such as external thermal insulation composite systems (ETICS) is challenging, which is why their recycling in the sense of a circular economy is currently hardly established. Therefore, the combined mechanical and thermochemical recycling of ETICS based on expanded polystyrene (EPS) is investigated experimentally and by simulating full process chains in order to evaluate circular economy opportunities. Model ETICS as example for building and construction waste is pretreated mechanically, followed by either pyrolysis and / or gasification steps, and full mass and energy balances are derived. By the combined recycling, inorganic compounds can be separated to a large extent allowing a pre-concentrate generation. The plastic-rich pre-concentrate is converted into either pyrolysis oil with a high styrene monomer content of 51 wt% or to synthesis gas in the subsequent thermochemical conversions. The holistic approach enables a high carbon recycling rate between 53 and 68 wt%. In addition, the investigation reveals technology limitations and opportunities to be further developed and optimized.