ASIA - In the fifth of our special editorial series ‘Bioplastics 101’, we discuss the life cycle analysis of bioplastics, from front of pipe through to end of pipe.
A key approach used when evaluating the sustainability of a packaging material is Life Cycle Analysis (LCA) – looking at a material’s complete life cycle from raw material extraction through materials processing, manufacture, distribution, use, repair and maintenance, and disposal or recycling.
This is also known as a “cradle to grave” analysis of the environmental impacts associated with all the stages of a material's life. Upon evaluation, what you would receive is an eco-profile, which gives information such as the total energy and raw materials consumed, and the total emissions to air, water, and soil from the cradle to the finished material/product.
Where the PLA bioplastic material is concerned, its manufacturers have consistently been highlighting what they say are the numerous front- and end-of pipe benefits of the material.
Front of pipe benefits
According to an independent peer-reviewed article published in the June 2015 edition of Industrial Biotechnology, titled “Life Cycle Inventory and Impact Assessment Data for 2014 Ingeo Polylactide Production” and written by NatureWorks – manufacturer of the Ingeo biopolymer – the production of Ingeo emits fewer greenhouse gasses (GHGs) than the comparable manufacture of all common petrochemical-based plastic.
Ingeo’s latest 2015 eco-profile, which is based on the latest version of major global LCA consultant Thinkstep’s (PE INTERNATIONAL) GaBi LCA software and database, follows the ISO 14040 and 14044 standards and concludes that the production of Ingeo polymer emits fewer greenhouse gases and consumes less non-renewable energy compared to commonly used plastics such as polystyrene (PS), polyethylene terephthalate (PET), and ABS.
Remember, the raw materials for bioplastics are sourced from plants such as corn. And plants absorb carbon dioxide from the atmosphere as part of photosynthesis to produce food.
That is one of the main reasons why the level of greenhouse emissions is so low for the biobased Ingeo: it is because of the uptake of atmospheric carbon dioxide during crop production – this biogenic carbon ends up in the biopolymer produced.
On the other hand, conventional plastic materials – which is fossil-based - do not absorb any atmospheric carbon dioxide during production.
End of pipe benefits
There are a number of ways that conventional packaging material waste is handled in waste management: composting, recycling, incineration, or landfill. Biopolymers are no different.
On their own, the composting of biopolymers makes little sense as no energy is recovered (unlike in incineration), there is no carbon storage, and there is certainly no reprocessing and reuse of materials into other useful products.
However compostable foodservice packaging, such as cups and plates, do serve a purpose as a tool for food waste diversion from landfill to municipal composting facilities – they help capture and avoid improper disposal, and divert organics from becoming methane generators in landfill.
Biopolymers such as PLA can also be recycled. As PLA has a clear spectrum, it can be detected with NIR (Near Infrared – the technology used in recycling facilities to distinguish all plastics) for effective separation of plastic recycling streams.
PLA can either be mechanically recycled, as are a number of conventional plastics, or chemically recycled – meaning, converted back into lactic acid for production back into biopolymers.
Meanwhile, when incinerated, energy can also be recovered from biopolymer waste.
Of course in many cities in Asia - where there is little or no composting, recycling or proper incineration facilities – a significant proportion of waste ends up in landfill, including conventional plastic and bioplastic packaging waste material.
What bioplastics manufacturers are saying though, is that even if their waste ends up in landfills, the material isbetter in terms of lower CO2 emissions and non-renewable energy usage when compared with fossil-based plastics – biopolymers are essentially stable in landfills with no statistically significant quantity of methane released.
In other words, the environmental impact of biopolymers in landfills, in terms of greenhouse gas release, is not significant.
See other articles in the Bioplastics 101 series:
- Bioplastics 101: What are Bioplastics?
- Bioplastics 101: The Sustainability of Bioplastics Packaging
- Bioplastics 101: The Market for Bioplastics
- Bioplastics 101: Potential for an ASEAN Bioplastics Industry
The full article is available in the January 2016 issue of Packaging Business Insight Asia. To find out more, click here.