A carregar...
Publicação
Environmental sustainability assessment of biodegradable bio-based poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from agro-residues
| Nome: | Descrição: | Tamanho: | Formato: | |
|---|---|---|---|---|
| 4.28 MB | Adobe PDF |
Orientador(es)
Resumo(s)
In the context of a circular bio-based economy, more public attention has been paid to the environmental sustainability of biodegradable bio-based plastics, particularly plastics produced using emerging biotechnologies, e.g. poly(3-hydroxybutyrate-co-3-hydroxyvalerate) or PHBV. However, this has not been thoroughly investigated in the literature. Therefore, this study aimed to address three aspects regarding the environmental impact of PHBV-based plastic: (i) the potential environmental benefits of scaling up pellet production from pilot to industrial scale and the environmental hotspots at each scale, (ii) the most favourable end-of-life (EOL) scenario for PHBV, and (iii) the environmental performance of PHBV compared to benchmark materials considering both the pellet production and EOL stages. Life cycle assessment (LCA) was implemented using Cumulative Exergy Extraction from the Natural Environment (CEENE) and Environmental Footprint (EF) methods. The results show that, firstly, when upscaling the PHBV pellet production from pilot to industrial scale, a significant environmental benefit can be achieved by reducing electricity and nutrient usage, together with the implementation of better practices such as recycling effluent for diluting feedstock. Moreover, from the circularity perspective, mechanical recycling might be the most favourable EOL scenario for short-life PHBV-based products, using the carbon neutrality approach, as the material remains recycled and hence environmental credits are achieved by substituting recyclates for virgin raw materials. Lastly, PHBV can be environmentally beneficial equal to or even to some extent greater than common bio- and fossil-based plastics produced with well-established technologies. Besides methodological choices, feedstock source and technology specifications (e.g. pure or mixed microbial cultures) were also identified as significant factors contributing to the variations in LCA of (bio)plastics; therefore, transparency in reporting these factors, along with consistency in implementing the methodologies, is crucial for conducting a meaningful comparative LCA.
Descrição
Funding Information:
The studied PHBV pellet production was carried out at a pilot scale (FCT-UNL, Portugal and IVV Fraunhofer, Germany) and subsequently simulated to an industrial scale (i.e. upscaling of 50 times) within the context of the Horizon project “Granting society with low environmental impact innovative packaging” (GLOPACK). The production at these two scales was assumed to obtain a similar function (or the same functional unit (FU), i.e. 1 kg of PHBV pellets formulated for food packaging to be delivered at the gate, including two main steps. PHBV powder was first produced from fruit residues via microbial synthesis, followed by extraction and purification, namely “PHBV powder production” hereafter. Secondly, the additive (i.e. boron nitride as a nucleating agent) was added to the PHBV powder (0.5 wt%) to increase the PHBV crystallinity, followed by compounding into pellets, referred to as “material processing”. Lignocellulosic fibres, e.g. milled wheat straws) were also considered as an optional filler (up to 20 wt%) (Fig. 1). More details regarding microbial synthesis can be found in Matos et al. (2021).
Funding Information:
We thank GLOPACK's Consortium partners for providing data and sharing expertise, in particular the colleagues from Instituto de Biologia Experimental e Tecnológica (iBET), University of Montpellier, Fraunhofer Institute for Process Engineering and Packaging IVV, and InnovEn, for assisting in acquiring the primary data and modelling the industrial production (upscaling).
Publisher Copyright:
© 2024 The Authors
Palavras-chave
Bio-based biodegradable plastic Biodegradability End-of-life Life cycle assessment (LCA) poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) Sustainability Environmental Engineering Waste Management and Disposal Management, Monitoring, Policy and Law SDG 7 - Affordable and Clean Energy SDG 9 - Industry, Innovation, and Infrastructure SDG 12 - Responsible Consumption and Production SDG 13 - Climate Action