煤炭中含量增加对燃煤发电厂排放的综合影响:联合实验室和实地实验
Yan Zhao1, Cheng Zhang1, Lun Ma1
1State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074, China.
Journal of hazardous materials
|April 7, 2024
概括
在煤炭中增加 (Ca) 有效地减少燃烧期间的有毒 (Se) 排放,通过促进其在飞灰中被捕获. 这种方法提高了Se的稳定性,并为排放控制提供了一个环境安全的解决方案.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 煤炭燃烧是全球有毒 (Se) 排放的主要来源.
- 煤炭中的无机元素在燃烧过程中影响Se的分离,而 (Ca) 与Se保留有显著的关系.
研究的目的:
- 研究煤灰中的 (Ca) 在燃烧过程中对 (Se) 保持的作用.
- 评估增加煤炭中Ca含量的有效性,以减少气态Se排放和改善飞中的Se捕获.
主要方法:
- 在高温 (1300°C) 上,分析灰中的Ca与Se保留之间的关系.
- 研究氧化与气态Se的化学反应及其对Se吸附能力在温度范围 (3001300°C) 的影响.
- 现场应用在一个350兆瓦的装置中,使用含量较高的碳化合物 (2.745.19重量%) 的煤来监测烟气和飞灰中的Se分布.
主要成果:
- 灰中的 (Ca) 与1300°C的Se保留有很强的相关性.
- 煤炭中Ca含量增加导致烟气中的Se质量分布减少 (3.54%至2.63%) 在空气预热器入口.
- 较高的含量导致飞灰中的含量增加,浸出率显著降低 (从4.8835.74%降至1.8726.31%),表明稳定性得到改善.
结论:
- 煤中的 (Ca) 通过促进其化学吸附到飞灰上,有效地阻碍了气态Se排放.
- 增加煤炭的Ca含量是一种可行且对环境安全的策略,用于将气态Se隔离到飞中,从而减少排放.
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