农作物秸秆燃烧PM2.5排放因子的研究

农作物秸秆燃烧是一类重要的生物质燃烧形式,已是大气细粒子的来源之一.建立了实验室模拟-稀释通道采样系统,并利用这一系统测定了浙江、四川、河南、河北、北京(主要粮食产区)五地的玉米、小麦和水稻秸秆燃烧过程中PM_2.5的排放因子.结果表明:实验室模拟明火燃烧的w(PM_2.5)为7.2～39.0 g/kg,与文献5],7]～8]中野外燃烧结果相似,表明两者燃烧状态具有相似性;排放因子受秸秆燃烧状态影响显著,闷火燃烧为明火燃烧的2.4～11.5倍;同时,农作物种类不同PM_2.5排放因子也存在明显差别;而排放因子随秸秆生长地域变化比较小. 

Emission Factor of PM2.5 from Crop Straw Burning

Crop straw burning, an important category of biomass burning, contributes significantly to airborne fine particles. This work is to characterize PM_2.5 emission factor of this source. For this purpose, a system of combustion simulation-dilution tunnel sampling was developed and PM_2.5 was measured during the combustion of wheat, corn and rice straws collected from five grain producing areas, including Zhejiang, Sichuan, Henan, Hebei and Beijing. The results showed that PM_2.5 emission factors from flaming simulation were 7.2 to 39.0 g/kg comparable with those from field burning, implicating that these two combustion conditions would be similar. Moreover, 2.4～11.5 times higher PM_2.5 emission factors were observed in smoldering combustion, indicating that combustion status would affect emission features remarkably. There were also novel differences in PM_2.5 emission among different crops. However, the difference of emission factors among the straw from different regions was relatively small.