A peer-reviewed article appearing in the journal of Polymer Degradation and Stability concludes that Ingeo™ biopolymer is essentially stable in landfills with no statistically significant quantity of methane released. This conclusion was reached after a series of tests to ASTM D5526 and D5511 standards that simulated a century’s worth of landfill conditions.
“This research is the latest in a series of NatureWorks initiatives aimed at understanding and documenting the full sustainability picture of products made from Ingeo,” said Marc Verbruggen, president and CEO, NatureWorks. “We work with a cradle-to-cradle approach to zero waste. What this means in terms of landfill diversion, for example, is ideally that Ingeo foodservice ware would be composted in order to enable the landfill diversion of a food-residual stream, and that Ingeo resins and fibers would be mechanically or chemically recycled and not landfilled. However, these systems are still emerging and developing. The reality today is that a percentage of Ingeo products end up in landfills. And now we can say with certainty that the environmental impact of that landfilling, in terms of greenhouse gas release, is not significant.”
Verbruggen added that several months ago Ingeo was the first biopolymer to receive tandem certifications for sustainable agricultural practices in growing feedstock. “NatureWorks is looking at sustainability from a 360-degree perspective – from sustainable agriculture to facilitating sustainable end-of-life scenarios for Ingeo bioplastic and fiber.”
Two scenarios tested
Conditions in landfills can vary considerably by geography, management practices, and age of waste. As a result, researchers Jeffery J. Kolstad, Erwin T.H. Vink and Bruno De Wilde, and Lies Debeer of Belgium-based Organic Waste Systems performed two different series of tests spanning a broad spectrum of conditions. The first was at 21˚ C (69.8˚ F) for 390 days at three moisture levels. The first series did not show any statistically significant generation of biogas, so the team decided to push the stress tests to a higher and more aggressive level and instituted a series of high solids anaerobic digestion tests. Today, some landfills are actively managed to act as “bioreactors” to intentionally promote microbial degradation of the waste, with collection and utilization of the by-product gas. To capture this scenario, the second series of tests were designed to simulate high solids anaerobic digestion under optimal and significantly accelerated conditions and were performed at 35˚ C (95˚ F) for 170 days. While there was “some” biogas released in this aggressive series of tests, the amount released was not statistically significant according to the peer reviewed research paper. Both series of tests were designed to represent an examination of what could happen under a range of significantly accelerated anaerobic landfill conditions and were roughly equivalent to 100 years of conditions in a biologically active landfill.
Download the complete 10-page study, Assessment of anaerobic degradation of Ingeo polylactides under accelerated landfill conditions. Products made from Ingeo span multiple industries and categories, including packaging, electronics, clothing, house wares, health and personal care items, semi-durable products, and the foodservice industry. View this special edition Ingeo LookBook for a sampling of the latest Ingeo innovations.
About NatureWorks LLC
NatureWorks LLC is a company dedicated to meeting the world’s needs today without compromising the earth’s ability to meet the needs of tomorrow. NatureWorks LLC is the first company to offer a family of commercially available, low-carbon-footprint Ingeo™ lactides and biopolymers derived from 100 percent annually renewable resources with performance and economics that compete with oil-based intermediates, plastics, and fibers, and provide brand owners’ new cradle-to-cradle options after the use of their products. NatureWorks is jointly owned by Thailand’s largest chemical producer, PTT Global Chemical, and Cargill, an international producer and marketer of food, agricultural, financial, and industrial products and services.
About Organic Waste Systems
Organic Waste Systems (OWS) is a world leading company in the construction and operation of anaerobic digestion plants for solid and semisolid feedstocks, in the biodegradability testing of biopolymers, and in waste management consultancy. The company started up in 1988 and has more than 20 full-scale reference plants in 10 different countries, treating source-separated and mixed household waste as well as energy crops. OWS developed the patented DRANCO process, which converts solid and semi-solid organic waste into renewable energy, biogas, and a stable humus-like compost. OWS also provides laboratory testing services for the determination of biodegradability and compostability of plastics, packaging materials, consumer products, detergents, etc. under strict quality conditions. The laboratory is ISO-17025 accredited and also very active in standardization of biodegradation test methods and specifications.
NatureWorksLLC, press release, 2012-09-13.