使用放射性PET塑料废弃物在混凝土中部分替代水泥?
K Grigoriadis1, J Bañuls-Ciscar1, A Caverzan2
1European Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027 Ispra, VA, Italy.
Waste management (New York, N.Y.)
|August 19, 2023
概括
玛辐射聚乙烯二甲 (PET) 废粉在作为部分水泥替代品使用时不会显著提高混凝土的强度. 这项研究验证了辐射PET在混凝土应用中无法恢复非辐射PET失去的机械强度.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 环境科学 环境科学
背景情况:
- 波特兰水泥生产对全球二氧化碳排放 (5-8%) 的贡献很大.
- 聚乙烯二甲 (PET) 废物是环境污染的主要因素.
- 之前的研究表明,玛辐射的PET废粉可以部分取代混凝土中的水泥,以减少二氧化碳足迹.
研究的目的:
- 独立评估和验证有关使用玛辐射PET废物粉末作为混凝土中部分水泥替代物的说法.
- 评估PET废物辐射对混凝土机械性能和二氧化碳减排潜力的影响.
主要方法:
- 实验室对不同水平 (2.5%,5%,5%,10%) 的混凝土粉末和砂进行研究,以PET废物代替水泥.
- 测试不同玛辐射剂量 (0,10,100kGy) 对PET废物的影响.
- 使用X射线衍射 (XRD),热重力测量分析 (TGA) 和差分扫描热量测量 (DSC) 的微结构分析.
主要成果:
- 与非辐射PET废物相比,PET废物的高达100kGy的马辐射并没有导致混凝土的机械强度明显恢复.
- 该研究发现,当放射性PET废物作为部分水泥替代品使用时,不会显著提高混凝土的机械强度.
- 微结构分析提供了对照射对PET的影响及其在水泥基质中的相互作用的见解.
结论:
- 作为部分水泥的替代品,使用玛辐射PET废弃物粉末并不能有效地减轻通常在非辐射PET废弃物中观察到的强度降低.
- 这些发现挑战了马辐射显著提高PET废物的可行性作为强度回收的混凝土添加剂的前提.
- 可能需要进一步的研究,以探索在建筑材料中利用PET废物的替代方法,或了解缺乏强度改善的根本原因.
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