通过从建筑和拆除 (C&D) 废弃物中制备回收水泥,回收聚合物和回收混凝土来封存碳
Jing Luo1, Rong Huang1, Junjie Wang1
1Department of Civil Engineering, Tsinghua University, Beijing 100084, China.
Materials (Basel, Switzerland)
|October 26, 2024
概括
中国中国中国中国.
科学领域:
- 环境科学 环境科学
- 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.
背景情况:
- 中国是世界上最大的建筑垃圾生产国.
- 目前在中国的废弃混凝土回收产生低质量的材料,与发达国家不同.
- 废混凝土的有效处置和再利用是一个重大的全球性问题.
研究的目的:
- 为高质量的回收混凝土生产引入混凝土循环模型.
- 探索有效利用废混凝土的技术手段.
- 评估回收混凝土的碳捕获潜力.
主要方法:
- 开发一个具体的循环模型.
- 技术手段的应用,包括有效的分离,碳封存和重新激活.
- 计算二氧化碳排放减少和碳汇潜力.
主要成果:
- 高质量的回收混凝土可以取代传统的混凝土,减少原材料消耗.
- 与普通波特兰水泥相比,回收水泥生产可以减少47% - 94%的二氧化碳排放.
- 全球将普通波特兰水泥替换为回收水泥,每年可以封存1.4至3.08千兆的二氧化碳.
结论:
- 拟议的混凝土循环模型能够有效地回收和利用废混凝土.
- 回收混凝土生产大大减少了碳排放,并产生了相当大的碳汇.
- 在全球范围内实施废混凝土回收利用可以减轻气候变化影响.
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