在可凝结颗粒物中的无机成分的评估,作为表面聚合,空间悬浮状态和颗粒大小的函数
Hongliang Guan1, Quanfeng Liu1, Wei-Ping Pan2
1Key Laboratory of Power Station Energy Transfer Conversion and System, Ministry of Education, North China Electric Power University, Beijing 102206, China.
Journal of hazardous materials
|May 17, 2024
概括
这项研究评估了空气污染控制装置 (APCD) 用于控制超低排放发电厂中的煤炭制颗粒物 (CPM). 湿式烟气脱硫 (WFGD) 显示了最高的去除效率,特别是对于超微粒的颗粒.
科学领域:
- 环境工程 环境工程
- 化学工程是化学工程的重要组成部分.
- 大气科学 大气科学
背景情况:
- 燃煤发电厂是颗粒物的重要来源,需要超低排放标准的先进控制技术.
- 传统的空气污染控制装置 (APCD) 在有效去除细颗粒和超细颗粒物 (CPM) 方面面临着挑战.
研究的目的:
- 评估超低排放发电厂中CPM在不同APCD中的去除效率和颗粒大小分布.
- 分析PCD处理后在CPM中的组成变化,包括金属元素和离子.
主要方法:
- 在湿静电沉器 (WESP),湿烟气脱硫 (WFGD) 和选择性催化减少 (SCR) 系统中对CPM去除效率和尺寸分布进行实验性评估.
- 在APCD处理前后,对CPM进行成分分析,重点关注主要金属元素和水溶性离子.
主要成果:
- WFGD显示了最高的整体CPM去除效率 (98%),特别是在超微粒子.
- WESP显示有效地去除了微微和超微微的CPM,但增加了超细的水溶性离子形成,导致整体效率为负.
- SCR的整体效率低 (34%),超细颗粒的去除率为负;微量元素的去除 (Hg,Se) 是有限的.
结论:
- 超细颗粒范围最容易受到APCD之间的效率差异的影响.
- 优化SCR条件以减少SO4 ((2-) /NH4 ((+) 形成和WESP喷雾系统对于在超低排放发电厂有效控制CPM至关重要.
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