Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Politecnico di Bari, Via E. Orabona n.4, 70125 Bari, Italy.
Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Politecnico di Bari, Via E. Orabona n.4, 70125 Bari, Italy.
Waste Manag. 2022 May 1;144:87-97. doi: 10.1016/j.wasman.2022.03.014. Epub 2022 Mar 22.
The use of bio-plastic-based packaging as an alternative to conventional plastic packaging is increasing. Among the plethora of different bio-based plastics, the most relevant ones are those that, at the end of their life, can be treated with the organic fraction of municipal solid waste. Even in these cases, their impact on the waste processing and recycling is not always positive. This study aim to assess on a laboratory scale the influence on combined anaerobic digestion and composting industrial processes of a bio-based plastic film, namely cellulose acetate (CA), in pure and modified (additions of additive) forms. CA films were mixed with organic waste and subjected to: (i) anaerobic digestion; (ii) active composting and (iii) two stages of curing composting. Anaerobic digestion and composting were monitored through methane yield and oxygen uptake respectively; additionally, the bio-plastics degree of disintegration was assessed during all the processes. The final disintegration of pure and modified CA was 73.82% and 54.66%, respectively. Anaerobic digestion contributes to the disintegration of the material, while aerobic treatment appears to be nearly ineffective, especially for modified CA. The presence of cellulose acetate during anaerobic digestion of food waste increased the methane yield by about 4.5%. Bioassay confirmed the absence of possible toxic effects on the final compost from the bio-plastic treatment. Although bio-based materials are not the only solution to plastic pollution, the findings confirm the need to upgrade the organic waste treatment plants and the necessity to revise the requirements for the use of compost in agriculture.
生物基塑料包装作为传统塑料包装的替代品的使用正在增加。在众多不同的生物基塑料中，最相关的是那些在其使用寿命结束时可以用城市固体废物的有机部分进行处理的塑料。即使在这些情况下，它们对废物处理和回收的影响也并不总是积极的。本研究旨在评估纤维素醋酸酯（CA）生物基塑料薄膜的纯形式和改性形式（添加添加剂）对联合厌氧消化和堆肥工业过程的影响。CA 薄膜与有机废物混合，并进行以下处理：（i）厌氧消化；（ii）活性堆肥和（iii）两阶段腐熟堆肥。通过甲烷产量和耗氧量分别监测厌氧消化和堆肥；此外，在所有过程中都评估了生物塑料的分解程度。纯 CA 和改性 CA 的最终分解度分别为 73.82%和 54.66%。厌氧消化有助于材料的分解，而好氧处理似乎几乎无效，特别是对于改性 CA。纤维素醋酸酯在食物废物的厌氧消化过程中存在时，甲烷产量增加了约 4.5%。生物测定证实了生物塑料处理对最终堆肥没有可能的毒性影响。虽然生物基材料不是解决塑料污染的唯一方法，但研究结果证实需要升级有机废物处理厂，并需要修订在农业中使用堆肥的要求。
