将煤粉在O2/N2与O2/CO2条件下进行沉降炉燃烧实验,研究了燃煤颗粒物的质量粒径分布、生成浓度以及元素组成特性。研究结果表明,燃煤颗粒物均呈三模态粒径分布,气氛的改变不影响各模态的分布趋势。相同O2含量条件下,与O2/N2气氛相比,O2/CO2气氛中PM10和PMa的生成浓度均降低,PM1中易挥发元素Na、K、S的含量升高,而难熔元素Si、Al、Mg、Ca、Fe的含量降低。随着O2浓度的增加,O2/N2燃烧气氛下PM10和PM1的生成浓度逐渐增加,O2/CO2燃烧气氛下PM10的生成浓度增加,而PM1的生成浓度先减小后增加。
Combustion experiments of a pulverized coal were conducted in a laboratory drop tube furnace (DTF) under O2/N2 and O2/CO2 conditions. The mass size distribution, concentration and elemental composition of generated particulate matter (PM) were investigated. The results showed that coal-derived PM was trimodally distributed with respect to particle size, which was not influenced by combustion conditions. Compared with the O2/N2 condition, under the O2/CO2 condition, both the inhalable particulate matter (PM10) and submicron particles (PM1) production decreased. PM1 contained higher concentrations of Na, K, S while lower concentrations of Si, Al, Mg, Ca and Fe. Under the O2/N2 condition, the PM10 and PM1 production increased with increasing O2 concentration. Under the O2/CO2 condition, with the increase of the O2 concentration, the PM10 production increased while the PM1 production decreased first and then increased.