由于被动CO2矿化,与石沉相关的渣渣属性的微结构分析
Faisal W K Khudhur1, John M MacDonald1, Luke Daly2
1School of Geographical and Earth Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
概括
废渣中的二氧化碳 (CO2) 矿化捕获每公斤9-30g的CO2. 这是一场大屠杀,大屠杀.
科学领域:
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
- 环境科学 环境科学
背景情况:
- 废渣中二氧化碳矿化是一种具有前景的碳捕获方法,能量投入较低.
- 以前的研究量化了理论上的二氧化碳捕获,但忽视了微观结构和矿物学影响.
- 了解这些因素对于优化基于渣的碳捕获至关重要.
研究的目的:
- 通过详细的微观结构特征来分析遗留的废渣样本中二氧化碳的吸收.
- 为了研究渣的物理性质与其二氧化碳吸收能力之间的关系.
- 为了确定在废渣中二氧化碳矿化过程中发生的矿物质变化.
主要方法:
- 用于孔隙空间分析的X射线计算机断层扫描 (XCT).
- 扫描电子显微镜 (SEM) 使用能量分散式X射线光谱 (EDS) 进行元素分布.
- 电子反射衍射 (EBSD) 用于矿物分布.
- 用X射线衍射 (XRD),X射线光 (XRF) 和热重力测量分析 (TGA) 进行全面的表征和二氧化碳量化.
主要成果:
- 吸收的二氧化碳范围大约在 9-30 g CO2/kg 渣.
- 渣渣样本呈现出显著的多孔性 (高达~30%的体积).
- 阿克马尼特 - 格列尼特矿物质占主导地位,与大气中的二氧化碳相互作用缓慢.
- 石被确定为沉的碳酸盐,与Si-O丰富层一起形成.
结论:
- 污泥的多孔微观结构和矿物成分显著影响二氧化碳矿化.
- 在渣中被动捕获二氧化碳是可行的,吸收取决于特定的渣特性.
- 微观结构和矿物学方面的考虑对于设计有效的大规模基于渣的碳捕获解决方案至关重要.
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