Evolution of granulometry of plastic fragments sampled during the composting experiment

The materials batch of the composting experiment containing the compostable plastics was regularly sampled during the process. These sampling was done using the standardized method NF EN 12579:(12579:2013, 2013). For a batch of compost (max 580 m³) it recommends taking 12 elementary samples, each weighing 1 kg, from various locations. The quartering method described in ASTM C702/C702M:2018 (C702/C702M:2018, 2018) was used to reduce the sample size without creating a systematic bias due to product heterogeneity and obtain a representative final sample of around 10 kg per batch and per sampling time. All the compost samples were air-dried. They were then passed through a series of sieves with decreasing mesh sizes to obtain eight fractions ranging from 10 mm to 0.2 mm. Each fraction was weighed, and its water content was determined.