Packaging plays an essential role in containing, protecting and preserving drinks and food. Among the various materials used for containers, glass stands out for its ability to be reused infinite times without its chemical components degrading, thus embodying the principle of the three Rs of sustainability: reuse, repair, recycle. In Italy, glass boasts an estimated recycling rate of 81,9% for 2024, confirming itself as one of the most recyclable materials.
Recycling performance of glass, PET, aluminum and multilayer polylaminate
The qualities of glass as a packaging material are explored in the study “The recyclability of container materials: the specificity of glass”, conducted by Professor Vincenzo Maria Sglavo of the University of Trento (Italy) and presented by Assovetro, the Italian association of glass manufacturers.
The study analyses the characteristics and the recyclability of the most common materials for packaging, including glass, PET, aluminium and multilayered polylaminate, highlighting their advantages and disadvantages.
Dark glass bottles, recycling over 90%
Marco Ravasi, President of Assovetro, underlined that correct recycling of packaging is fundamental for a sustainable future, and glass is positioned as an ideal material thanks to its ability to be reused e recycled infinite times without losing its properties. For example, the recycling of dark bottles reaches 90%.
Additionally, glass is preferred for long-term storage of contents, despite its weight checked greater than other materials, an aspect on which work is underway to improve its efficiency. ‘In some cases we have reached the point where 75cl still wine bottles of 300 grams‘, says Ravasi.
Eco-property, advantages and disadvantages
Professor Sglavo’s study evaluates the ecological footprint of the four materials (glass, PET, aluminum and multilayer) considering the production of virgin material, the transformation process and the production with recycled material.
Glass is distinguished by requiring less energy in production, emit less CO2 and consume less water than other materials.
For example, to produce a kilogram of glass only necessary 14 liters of water, compared to 1.350 litres of multilayer and 1.000 litres of aluminium.
Furthermore, glass has the lower CO2 footprint (600 grams per kg) among the materials analyzed, along with multilayer (1 kg per kg). However, glass has a high density, which makes it heavier than other materials, such as aluminum.
Recycling and separate waste collection
Glass and aluminum are the most efficient materials in recycling, with high rates and consolidated supply chains.
Glass, in particular, guarantees a high quality secondary raw material, reducing waste, CO2 emissions and energy consumption. Each ton of recycled glass cullet reduces emissions by 300 grams of CO2.
Aluminium, although recyclable, presents critical issues related to oxidative phenomena which reduce their efficiency.
PET, used for bottles and containers, in Italy has a recycling rate of 60% in 2022, while the multilayer polylaminate has limited recyclability, with only the paper fraction recoverable.
Glass container production: trends and challenges
In 2024, the production of glass containers in Italy and in Europe it has recorded a 3,4% decrease, influenced by the geopolitical crisis, the increase in energy prices and the decline in consumption. In particular, the production of bottles decreased by 5%, while the food jars saw an increase of 24,5%.
Foreign trade was affected by the negative trend, with a 7,8% drop in exports and 9,7% in imports of bottles, while jars recorded an increase of 44% in imports and 13,8% in exports.
In the European context, glass container production decreased by 8% in tonnes and 5% in units between the first half of 2023 and the first half of 2024, due to the war in Ukraine, oversupply and reduced demand.
Marta Strinati
Cover image: Photo by NoName_13 da Pixabay
Professional journalist since January 1995, he has worked for newspapers (Il Messaggero, Paese Sera, La Stampa) and periodicals (NumeroUno, Il Salvagente). She is the author of journalistic surveys on food, she has published the book "Reading labels to know what we eat".
