Bottles PLA bottles
Bottles PLA bottles Rethinking the end of life for PLA food containers Figure 1: NaKus renewable and compostable PLA-bottles By: Fabian Coosmann Key Account- and Projektmanagement NaKu Wiener Neustadt, (Vienna), Austria In 2011, NaKu brought its first PLA bottle to the market. Since then, the Austrian company has been supplying its customers with bottles and jars in a variety of forms and shapes for different applications, such as beverages, cosmetics and solid foods. NaKu has thus established itself as a pioneer supplier for renewable and compostable food containers. Many of NaKu’s customers consider conventional plastic bottles a no go. “Modern and sustainable products need innovative packaging,” is a much-heard sentiment. Today, the trend in the market is to move away from plastic packaging and to pivot towards packaging that is 100 % renewable and compostable - two properties inherent to the NaKu bottle. The change from conventional to biobased packaging usually attracts a lot of attention and raises customer questions. It is therefore extremely important to be optimally prepared and to have the answers to these questions ready to ensure a successful market launch. As a bottle supplier, NaKu not only supplies the product but also provides supporting information, such as CO 2 -studies or photo documentation of the biodegradation process of the PLA bottles. Recently, NaKu conducted a LCA screening analysing the global warming potential of its PLA bottles. It showed a reduction of approximately 35 % in greenhouse gas emissions from cradle to gate compared to bottles made from conventional PET. Earlier cradle to grave studies came to a similar conclusion: PET bottles are more damaging to the climate than PLA bottles [1,2]. A closer look at the end of life options of PLA bottles reveals two viable alternatives, as shown in the “double loop of sustainability” developed by NaKu. The first option consists of biodegradation in a composting or AD (anaerobic digestion, or biogasification) plant, which makes sense either if the bottle still contains high amounts of organic material, or if the biogas resulting from anaerobic digestion can be used to generate energy. The second - and preferred - end of life option is mechanical, chemical or solvent based recycling. According to a recent life cycle analysis, all three recycling methods are preferable to energy recovery, if you look at it from an ecological point of view [3]. Hence, recycling is clearly the way to go. This notwithstanding, most PLA bottles still end up being incinerated with energy recovery. This third option can at least exploit the solar energy that is stored in the PLA. In other words, incinerating PLA generates a kind of “renewable energy”. However, it is NaKu’s stated goal to avoid even that by establishing recycling solutions, as recycling has been demonstrated to be the best end of life scenario. NaKu is now setting up a recycling project in which customers, sorters, recyclers and research institutes are involved, with the aim of establishing a pilot recycling stream for PLA bottles. To speed up the process, NaKu is giving discounts to customers who agree to return a certain number of postconsumer bottles for recycling. The resulting rPLA will go back into bottle production. Ultimately, the project should show that recycling and bioplastics are not a contradiction, but instead complementary and must go hand in hand. “Everybody who thinks that the success story of PLA will only continue if its recycling is accelerated is warmly invited to participate in the project”, says NaKu CEO Johann Zimmermann. It’s crystal clear to NaKu that the future is renewable, biodegradable AND recyclable, simply because one circle is not enough. NaKu is seeking to come in contact with parties interested in participating in the recycling project. www.naku.at 14 bioplastics MAGAZINE [04/20] Vol. 15
Bottles References: [1] Papong, S. et al. (2013). Comparative assessment of the environmental profile of PLA and PET drinking water bottles from a life cycle perspective. Journal of Cleaner Production, 65, 539-550. [2] Shen, L., Worell, E., & Patel, M. K. (2012). Comparing life cycle energy and GHG emissions of biobased PET, recycled PET, PLA, and man-made cellulosics. Society of Chemical Industry and John Wiley & Sons, Ltd. [3] Maga, D., Hiebel, M., & Thonemann, N. (2019). Life cycle assessment of recycling options for polylactic acid. Resources, Conservation & Recycling. COMPEO Leading compounding technology for heat- and shear-sensitive plastics Figure 2: NaKu-bottles after 0, 4 and 9 days in an industrial composting facility 0,12 — 0,1 — 0,08 — 0,06 — 0,04 — 0,02 — 0 — NaKu bottle PET bottle Material Transport Production Figure 3: global warming potential in kg CO 2 -eq of a NaKu-bottle compared to a PET-bottle Uniquely efficient. Incredibly versatile. Amazingly flexible. With its new COMPEO Kneader series, BUSS continues to offer continuous compounding solutions that set the standard for heat- and shear-sensitive applications, in all industries, including for biopolymers. • Moderate, uniform shear rates • Extremely low temperature profile • Efficient injection of liquid components • Precise temperature control • High filler loadings www.busscorp.com Figure 4: NaKus double loop of sustainabilty bioplastics MAGAZINE [04/20] Vol. 15 15
