煤炭飞灰混合比率对生物质废弃物结构修改和金属迁移的影响
Shuo Yang1, Shaohui Wang1, Yudong Fu1
1Key Laboratory of Liaoning Province for Clean Combustion Power Generation and Heating Supply Technology, Shenyang Institute of Engineering, Shenyang 110136, China.
Energy & fuels : an American Chemical Society journal
|August 23, 2023
概括
煤 (CFA) 的添加改善了生物质灰沉积,通过创建一个多孔结构和结合金属. 较高的CFA比率增加了耐火晶体的形成,影响了渣的特性.
科学领域:
- 燃烧科学与工程 燃烧科学与工程
- 材料科学 材料科学 材料科学
- 环境工程 环境工程
背景情况:
- 生物质燃烧可能会导致由于金属而导致有问题的灰沉积.
- 煤炭飞灰 (CFA) 作为修改灰沉积特征的添加剂正在被探索.
- 了解生物质灰和CFA之间的相互作用对于优化燃烧过程至关重要.
研究的目的:
- 为了研究不同煤炭飞灰 (CFA) 添加比对生物质灰沉积的影响.
- 分析灰样本的微观结构变化和化学成分.
- 了解CFA在气相金属异质去除中的作用.
主要方法:
- 用电子显微镜 (EM),扫描电子显微镜 (SEM) /能量分散扫描 (EDS) 和X射线衍射 (XRD) 分析了灰沉积样本.
- 分析是在三个不同的温度 (960°C,855°C和820°C) 进行的.
- 将CFA的不同比例添加到生物质灰中 (Mr = 1:1, 1.5:1, 2:1).
主要成果:
- 在Mr = 1: 1时,一个"珊瑚礁"类似的多孔结构形成,米灰作为骨架和CFA产品作为结合剂.
- 观察到球形和丝状SiO2,Al2O3,以及具有高点K-Al-Si盐的酸盐晶体,表明CFA在金属捕获中的作用.
- 降低CFA比率 (Mr = 1.5:1或 2:1) 增加了晶体含量,MgO,Fe2O3,Al2O3可能形成耐火前体. 金属 (K2O,KCl) 作为结合剂起作用.
结论:
- 煤炭飞灰的添加显著改变了生物质灰沉积特征,促进了多孔结构,并促进了金属的固定.
- 碳酸对金属的异质固化作用通过形成高点盐而显而易见.
- 在CFA中和硫活性部位在吸附方面发挥着关键作用,这表明灰管理策略的潜力.
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