摘要
随着燃煤电厂以及钢铁等非电行业超低排放改造的进行,固定污染源可过滤颗粒物(FPM)排放浓度逐渐降低,可凝结颗粒物(CPM)的排放逐步引起关注.然而目前对CPM的认识不足,尚没有国际统一的标准测量方法.本研究分析了可用于固定源CPM测量的3种方法,包括冷凝法、稀释间接法和稀释直接法,并在燃煤电厂、钢铁焦化厂和钢铁烧结厂等固定源进行了CPM现场测量.结果表明,8个电厂和钢铁厂冷凝法测得的CPM质量浓度均显著高于稀释间接法和稀释直接法测量结果.冷凝法测得的CPM中含有大量的SO24-、Cl-等水溶性离子,其浓度显著高于稀释间接法和稀释直接法测量结果.稀释直接法测量的CPM浓度相对较低.冷凝法测量过程中由于水蒸气过饱和冷凝成水吸收SO2和HCl等易溶于水的气体,进而显著高估了CPM实际排放浓度.稀释间接法能模拟实际大气环境中CPM的形成过程,且不存在冷凝水吸收等问题.
With the retrofitting of coal-fired power plants and steel plants for ultra-low-emission control,the concentration of filterable particles(FPM)from these sources is decreasing gradually.The condensable particle matter(CPM)draws more attention.The understanding of CPM emission concentration and chemical characteristics is still limited.There has been no standard determination method of CPM in China until now.In this study,three methods,including the dry impinger method(US EPA method 202),indirect dilution method,and direct dilution method,are discussed and compared in measuring CPM emissions from coal-fired power plants,coke-making plants and sintering plants.The results show that method 202 overestimates the emissions of CPM,due to the fact that the gaseous HCl or SO2 dissolves into condensable liquid and cannot be completely eliminated by N2 purging after sampling.Instead,CPM measured using the indirect dilution method better represents its real emission levels into the atmosphere.
作者
蒋靖坤
邓建国
王刚
张莹
李妍菁
段雷
郝吉明
JIANG Jing-kun;DENG Jian-guo;WANG Gang;ZHANG Ying;LI Yan-jing;DUAN Lei;HAO Ji-ming(School of Environment,Tsinghua University,Beijing 100084,China;State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex,Beijing 100084,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2019年第12期5234-5239,共6页
Environmental Science
基金
国家重点研发计划项目(2018YFC0213202)
