将建筑和拆除废物回收利用成混凝土的有效方法:生命周期方法
Abhijit Mistri1,2,3, Cheela Venkata Ravi Sankar4,5, Brajesh Kumar Dubey4
1Department of Civil Engineering, Indian Institute of Technology, Kharagpur, West Bengal, India.
概括
生命周期分析显示,热处理和机械研磨对回收粗聚合物 (RCA) 的环境影响最高. 加速碳化也是一个主要的贡献者,但可再生能源可以改变处理方法的适用性.
科学领域:
- 土木工程 土木工程是指土木工程.
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
背景情况:
- 将建筑和拆除废弃物 (CDW) 循环利用为回收粗聚合物 (RCA) 对于可持续建筑至关重要.
- 对于RCA,存在各种物业增强技术,但它们的相对环境可持续性仍然不清楚.
研究的目的:
- 通过生命周期分析 (LCA) 来比较不同RCA治疗方法对环境的影响.
- 为了确定最合适和可持续的RCA处理方法,以最小的环境足迹.
主要方法:
- 使用SimaPro软件进行的生命周期分析 (LCA),遵循ISO 14040/44指南.
- 功能单位定义为1经过处理的RCA的制备,重点是减少吸水.
- 通过改变能源组合进行敏感性分析,包括基于可再生能源的场景.
主要成果:
- 在RCA去除方法中,热处理和机械研磨具有最高的环境排放.
- 加速碳化是加强附着砂的主要排放贡献者,其次是微生物处理.
- 敏感性分析表明,基于可再生能源的能源组合可以改变首选的处理方法选择.
结论:
- RCA处理方法对环境的影响有很大差异,热和机械方法是最具影响力的.
- 能源组合的选择,特别是可再生能源的整合,极大地影响了RCA处理的可持续性评估.
- 在采用任何RCA处理技术之前,建议进行初步的特定位置的影响评估.
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