And Multilayer Tetra Pak Juice Packaging Systems
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103 A publication of CHEMICAL ENGINEERING TRANSACTIONS VOL. 87, 2021 The Italian Association of Chemical Engineering Online at www.cetjournal.it Guest Editors: Laura Piazza, Mauro Moresi, Francesco Donsì Copyright © 2021, AIDIC Servizi S.r.l. DOI: 10.3303/CET2187018 ISBN 978-88-95608-85-3; ISSN 2283-9216 Comparative Life Cycle Assessment of Polyethylene Terephthalate (PET) and Multilayer Tetra Pak Juice Packaging Systems a,b a a Marina Stramarkou *, Christos Boukouvalas , Panagiota Eleni , Dimitrios c a Karalekas , Magdalini Krokida a School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechneiou, Zografou Campus, 15780, Athens, Greece b Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research “Demokritos”, Athens, Greece c Department of Industrial Management and Technology, University of Piraeus, A. Dimitriou 80, 18534, Piraeus, Greece [email protected] Food packaging provides many vital functions including protection, storage and preservation of products, as well as, information to consumers. However, the overall packaging life cycle generates significant environmental impacts since its production exploits natural resources and energy and causes environmental emissions. Moreover, packaging wastes generate increasing disposal issues, being the second largest fraction of municipal wastes after the organic fraction. During the last years there is focus on the environmental performance of juice packaging systems. Polyethylene terephthalate (PET) bottles and Tetra Pak multilayer packaging arethe dominant juice packaging options. Life cycle assessment (LCA) techniques are used to improve the understanding, as well as, to compare the environmental characteristics of different packaging systems. This research assesses the environmental impact of the two commonest juice packaging options, including their production along with their final disposal (landfilling, incineration and recycling). The aim is to compare the footprints of PET and Tetra Pak packaging, identify the hot spots and finally discover the most environmentally benign juice packaging. LCA was performed using GABI software, following the ISO 14040 series recommendations, while the impact assessment was carried out using ReCiPe 2016. The results showed that Tetra Pak was environmentally superior to alternative PET packaging in 12 of the 18 total impact categories. In fact, their differences were significant in climate change and fossil depletion caegories, the environmental importance of which is assessed by the Federal Environment Agency as "very high" and "high" respectively. Considering the extended shelf life of juices with Tetra Pak, andthe reduced environmental footprint, it can be concluded that there are clear environmental advantages for multilayer Tetra Pak juice packaging over PET bottles. Keywords: climate change, environmental footprint, end-of-life 1. Introduction The traditional functions of food packaging are to contain and protect food from degradation processes, as well as, to provide information to consumers about the included ingredients and the nutritional value. Packaging provides three main categories of protection: physical protection against mechanical damage during distribution; biological protection against microorganisms, insects or animals and chemical protection against modifications in composition caused by exposure to gases (usually oxygen), moisture or light (Ramos et al., 2015). The beverage sector uses millions of tonnes of packaging per year with juice packaging being the most competitive segment in the global beverage packaging industry. Packaging constitutes a major issue in preserving fruit and vegetable juices. As a result of the emerging consumption of juices, the global juice packaging market has achieved a strong growth and the packaging industry has greatly evolved over the last two decades mainly in terms of packaging materials (Falguera and Ibarz, 2014; Borah and Dutta, 2019). Paper Received: 15 September 2020; Revised: 7 February 2021; Accepted: 9 May 2021 Please cite this article as: Stramarkou M., Boukouvalas C., Eleni P., Karalekas D., Krokida M., 2021, Comparative Life Cycle Assessment of Polyethylene Terephthalate (PET) and Multilayer Tetra Pak Juice Packaging Systems,Chemical Engineering Transactions, 87, 103-108 DOI:10.3303/CET2187018 104 The use of plastics and especially polyethylene terephthalate (PET) in juice packaging is increased due to the low raw material’s cost and its functional advantages, such as the excellent mechanical and optical properties (Falguera and Ibarz, 2014; Ramos et al., 2015). However, plastics’ variable permeability to light, gases and low molecular weight molecules (Ramos et al., 2015) along with the poor protection of the quality of oxygen- sensitive beverages over long periods are major concerns for their use in juices (Ros-Chumillas et al., 2007). Nowadays consumers’ demand for safer products with higher quality lead the industrial packaging sector to face some remarkable advances (Ramos et al., 2015). One of them is Tetra Pak multilayer packaging, which is produced by laminating six layers of stiff paper (75% of the packaging mass), low density polyethylene (LDPE) (20%) and aluminium foil (Al) (5%). The combination of materials results in the added advantage of properties from each individual material and specifically the rigid shape of paper, the outstanding barrier properties against light, water vapour, oxygen and microorganisms of Al and the layer bonding function of LDPE. Its low weight and cost and the extension of juice shelf life are among the advantages of Tetra Pak multilayer packaging. However, the recycling of Tetra Pak still remains a challenge (Zawadiak, 2017). Nowadays, PET and Tetra Pak packaging systems present the most common options for the packaging of fruit juice products. The packaging sector produces approximately 2% of the gross national product in developed countries and about half of this packaging is used in food industry. Overall, despite its undeniable usefulness, the life cycle of packaging creates significant environmental impacts. Indeed, its production exploits natural resources and energy and causes environmental emissions (Bertolini et al., 2016). In addition, packaging waste creates disposal issues, making it the second largest fraction of municipal waste after the organic fraction and the percentage is increasing every year (Pasqualino et al, 2011). The contribution of packaging to the overall environmental impact on food supply chains has led to legislation, such as the European Council (1994), but also to a number of studies focusing on packaging management (Tencati et al., 2016; Beitzen-Heineke et al., 2017). The contribution of juices to food packaging fraction is the highest (Pasqualino et al. , 2011). It is therefore crucial to assess the environmental impacts of their entire life cycle in order to implement improvements that promote their sustainability. The first step towards improving a process or product is to properly record the current situation in order to evaluate and compare it with any future changes (Boustead, 1993). The comparison of materials and processes to determine the optimum choice presents difficulties. Life Cycle Analysis (LCA) is a scientific method developed to help address the acute environmental problems of recent years, presenting a wide variety of variations (Guinee, 2002). LCA is the most suitable and valid tool to cover the need for assessment of environmental behavior of products and processes in a reliable way since it is the compilation and evaluation of the inputs, outputs and the potential environmental impacts of a product system throughout its life cycle, as defined by the International Organization for Standardization in the ISO 14040:2006 (ISO, 2006). The aim of the present study is the assessment of the environmental impact of the two commonest juice packaging options, namely PET and Tetra Pak multilayer packaging systems, including their production along with their final disposal (landfilling, incineration and recycling). The packagings will be compared with each other in terms of their environmental aspects in order to discover the most environmentally benign alternative. 2. Materials and Methods LCA study was performed on GABI ts (v8.7.0.18) software following the ISO 14040 series recommendations (14040:2006 and 14044: 2006). The impact assessment was carried out using ReCiPe 2016 (H) and midpoint impact categories focusing on single environmental problems. 2.1 Goal and Scope The goal of this LCA was to evaluate and compare, in terms of their environmental impacts, two different process chains for the manufacturing and end-of-life of two fruit juice packaging systems: polyethylene terephthalate (PET) bottles and Tetra Pak multilayer packaging. This study’s goal was to find the packaging having the lowest environmental impact. 2.1.1 Functional Unit The functional unit was defined as the packaging containing 10−3 m3 (one liter) of juice, excluding the cap. PET packaging of 10−3 m3 of refrigerator juice weighted 48.80 g and Tetra Pak packaging 34.96 g. 2.1.2 System Boundaries The production and end of life of PET and Tetra Pak packaging systems are the processes that present the greatest changes in the environmental footprint of these packagings. Therefore, processes, such as the filling with juice, the transport and distribution, as well as, the consumption of the products were excluded from the study since they increase the complexity