Yan Qin, Kong Shao-Fei, Liu Hai-Biao, Wang Wei, Wu Jian, Zheng Ming-Ming, Zheng Shu-Rui, Yang Guo-Wei, Wu Fang-Qi
Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing 210044, China.
Department of Atmospheric Sciences, School of Environmental Studies, China University of Geosciences(Wuhan), Wuhan 430074, China.
Huan Jing Ke Xue. 2018 Apr 8;39(4):1502-1511. doi: 10.13227/j.hjkx.201707063.
Based on a dilution sampling system and domestic burning tests, size-segregated particles emitted from burning of three kinds of honeycomb coals (in view of flaming and smoldering burning conditions) and four kinds of raw coals, were collected by cascade impactors (FA-3). The contents of V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Sb, and Pb were analyzed to get their emission factors (EFs) in different particle size fractions. Results indicated that:① Zn and Pb dominated the emitted mass of heavy metals from chunk (53.16%-65.76%) and honeycomb (96.08% in 0.43 μm) during the flaming combustion condition. However, the emission of Ni was increased from 30.70% to 52.36% in the smoldering condition. Thus, combustion condition may affect the composition of heavy metals in particle matters. ② In the flaming condition, both chunk and honeycomb emission factors of heavy metals were concentrated under 1.1 μm, while the larger sized particles in the range of 5.8-10 μm were distributed. So, heavy metal components may shift to the larger size of the particles at lower combustion temperatures. ③ Fine particle matters(PM) was divided into three categories based on the size distribution of 11 kinds of heavy metal emission factors. The maximum emission values of As and V fell under the PM size category of 5.8-10 μm. The fourth cycle transition metal elements, such as Cr, Mn, Cu, Ni, and Co, fell in the range of 1.1-2.1 μm and these elements represented similar emission characteristic features. Other elements, such as Pb, Sb, Cd, and Zn, were concentrated in sizes less than 0.43 μm. ④ The additive in the honeycomb during the process may import several kinds of heavy metals and may change the combustion temperature, which remodels the mechanism of heavy metal emission. Thus, honeycomb coal may emit different heavy metals under different combustion conditions.The heavy metal emission mechanism during honeycomb coal combustion needs further investigation and the emission reduction effects (especially of heavy metals) needs to be re-estimated.
基于稀释采样系统和国内燃烧试验，通过级联撞击器（FA - 3）收集了三种蜂窝煤（考虑明火燃烧和阴燃条件）以及四种原煤燃烧排放的粒径分级颗粒物。分析了钒（V）、铬（Cr）、锰（Mn）、钴（Co）、镍（Ni）、铜（Cu）、锌（Zn）、砷（As）、镉（Cd）、锑（Sb）和铅（Pb）的含量，以获取它们在不同粒径分数下的排放因子（EFs）。结果表明：① 在明火燃烧条件下，锌（Zn）和铅（Pb）在块煤（53.16% - 65.76%）和蜂窝煤（在0.43μm粒径时为96.08%）排放的重金属质量中占主导。然而，在阴燃条件下镍（Ni）的排放量从30.70%增加到52.36%。因此，燃烧条件可能影响颗粒物中重金属的组成。② 在明火条件下，块煤和蜂窝煤的重金属排放因子都集中在1.1μm以下，而在5.8 - 10μm范围内存在较大粒径的颗粒分布。所以，在较低燃烧温度下，重金属成分可能会向较大粒径的颗粒转移。③ 根据11种重金属排放因子的粒径分布，细颗粒物（PM）被分为三类。砷（As）和钒（V）的最大排放值出现在5.8 - 10μm的PM粒径类别中。第四周期过渡金属元素，如铬（Cr）、锰（Mn）、铜（Cu）、镍（Ni）和钴（Co），落在1.1 - 2.1μm范围内，并且这些元素表现出相似的排放特征。其他元素，如铅（Pb）、锑（Sb）、镉（Cd）和锌（Zn），集中在小于0.43μm的粒径范围内。④ 蜂窝煤生产过程中的添加剂可能引入几种重金属并可能改变燃烧温度，这重塑了重金属排放机制。因此，蜂窝煤在不同燃烧条件下可能排放不同的重金属。蜂窝煤燃烧过程中的重金属排放机制需要进一步研究，并且减排效果（尤其是重金属的减排效果）需要重新评估。
