UPM Biofore Magazine 1-2019

WHAT IS PLASTIC?

RENEWABLE PLASTIC The raw material used for making bio-based plastic is renewable biomass, such as sugar cane, maize, cellulose or renewable waste from the food industry (complying with Standard EN 16575 in Europe). Renewable plastic is not always biodegradable or compostable. Biomass can be used to manufacture different plastics, such as polyethylene, polypropylene and polyactide. BIODEGRADABLE PLASTIC Biodegradable plastics decompose in specific conditions. This is achieved when microorganisms metabolise and break down the structure into metabolic products such as nitrogen compounds, carbon dioxide and water. Biodegradable plastic can be bio- or fossil-based. All bio-based plastics are not biodegradable. The efficiency of biodegradation depends on the structure of the plastic and the surrounding conditions. Biodegradable plastics are not recyclable. COMPOSTABLE PLASTIC Compostable plastic is both degradable and biodegradable. Composting is the decomposition of waste primarily into carbon dioxide, water and humus. The process is usually accelerated in an industrial composter. There is no uniform definition for the environment or duration of the biodegradation process, but EN 13432 lays down standards for plastics labelled as “compostable”.

MASS BALANCE CALCULATION Mass Balancing is a method indicating the amount of materials (or mass) entering and leaving a production system. The calculation methodology compares the input of renewable bio-based feedstock going into production against the output of renewable material in the end product. RECYCLED PLASTIC More and more plastic is being collected for recycling. Plastic can be recycled either mechanically or chemically. Almost all product packaging, containers and bags made from plastic can be recycled. They must be rinsed or wiped clean before being collected. Labels do not have to be removed. In chemical recycling, plastic is broken down into its source materials or other base chemicals that can be used in plastic production or other petrochemistry products. Chemical recycling is a newly emerging field. MICROPLASTICS Microplastics are tiny pieces of plastic smaller than five millimetres in diameter. Tiny fragments of rubber are also often called microplastics. Microplastics find their way into water from several sources, for example when products wear out, when waste decomposes, and when textiles are washed. Microplastics are also added to enhance certain product properties, and this is currently being restricted everywhere. Microplastics, their effects and emission management are being researched widely.

states Hanna Koivula , lecturer in packaging technology at the University of Helsinki. “Packaging preserves nutrients and ensures that the product arrives fresh at its destination. The process should be designed to work as efficiently as possible, with an eye to future challenges such as ongoing urbanisation,” Koivula continues. Plastic remains popular due its many unrivalled properties. It is cheap, durable and cost-efficient, and it can be shaped into any form. Although fibre- based alternatives are being developed rapidly, they have yet to match the performance of conventional plastic. Milk cartons straight from the forest The best end result is often reached

through cross-industry collaboration. In February, UPMBiofuels launched a collaborative project with international dairy corporation Arla, packaging company Elopak, and chemical producers Dow. As part of the project, UPM supplies wood-based UPMBioVerno naphtha to Dow, who refine it into plastic granules. Norwegian Elopak, which manufactures packaging for Arla, utilises these granules to replace fossil-based rawmaterials. “This is an impressive project linking together the food, packaging, chemical and forest industries. Every tonne of plastic produced from wood-based UPMBioVerno naphtha replaces a tonne of plastic produced from fossil-based, non-renewable raw materials,” describes Helin.

The naphtha is produced from crude tall oil, which is a side stream from pulp production. In the first phase, it will replace fossil-based plastic rawmaterials worth the plastic coating of 40 million cartons based on mass balance. The wood-based plastic used in Arla’s dairy cartons reduces the need for fossil-based plastics by approximately 180,000 kg per year, which is roughly equal to 700,000 plastic buckets. Meanwhile, it decreases the carbon footprint of the packaging by a fifth. “A one-litre cardboard dairy carton has a 3.4 gram plastic coating. We wanted to offer a solution that is sourced entirely from the forest, using wood-based rawmaterial both for the carton and the plastic coating. The new packaging can be

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