水泥碳化对气候的好处被高估了
Elisabeth Van Roijen1, Kati Sethares1, Alissa Kendall1
1Department of Civil and Environmental Engineering, 2001 Ghausi Hall, University of California, Davis, 95616, USA.
Nature communications
|June 6, 2024
概括
水泥碳化重新吸收大量的二氧化碳,但其缓慢的速度减少了60%的气候效益. 拆除排放可以抵消碳吸收,因此需要准确的气候影响评估来制定脱碳战略.
科学领域:
- 环境科学 环境科学
- 气候科学 气候科学
- 材料科学 材料科学 材料科学
背景情况:
- 水泥行业是主要的二氧化碳排放者,使得快速脱碳对于气候目标至关重要.
- 之前对通过水泥碳化捕获碳的评估可能因过度简化而高估了其气候效益.
- 了解水泥材料中二氧化碳吸收和释放的动态对于有效减缓气候变化至关重要.
研究的目的:
- 量化水泥碳化总量及其对累积辐射强迫的动态影响.
- 通过考虑其缓慢的速度和寿命终端排放,重新评估水泥碳化对气候的好处.
- 分析脱碳战略对碳化过程和整体气候影响的影响.
主要方法:
- 从1930-2015年全球建模水泥碳化,以估计二氧化碳再吸收.
- 对碳化率对累积辐射强迫的动态影响的分析.
- 在拆除过程中吸收的二氧化碳与混凝土粉碎产生的生命期末排放量进行比较.
- 脱碳化策略的灵敏度分析,包括补充的水泥材料,对碳化.
主要成果:
- 从1930年到2015年,全球大约有138亿公 (Gt) 的二氧化碳通过水泥碳化再吸收.
- 与表面吸收相比,碳化的缓慢速度将其对气候的好处减少约60%.
- 来自混凝土的寿命末期拆除排放量可以与同一阶段的碳吸收量相比较.
- 脱碳化策略可以改变碳化过程以及排放和吸收的时间.
结论:
- 由于其缓慢的动力学,水泥碳化对气候的好处显著减少.
- 准确评估二氧化碳的吸收和释放,包括生命周期结束的排放,对于评估水泥对气候的影响至关重要.
- 这项研究为了解水泥碳化在脱碳化中的作用提供了更现实的框架,纠正了对其益处的错误解释.
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