云南省八种主要乔木燃烧释放烟气及颗粒物特性分析

为探究乔木燃烧释放烟气及颗粒物特性，运用自主研发的可燃物燃烧烟气分析系统，对云南省主要乔木树种滇青冈（Cyclobalanopsis glaucoides）、光叶石栎（Lithocarpus mairei）、旱冬瓜（Alnus nepalensis）、华山松（Pinus armandii）、金合欢（Acacia farnesiana）、麻栎（Quercus acutissima）、栓皮栎（Quercus variabilis）、云南油杉（Keteleeria evelyniana）的不同器官（枝、叶、皮）分别进行模拟燃烧，实测其在不同燃烧状态（阴燃/明燃）下释放的CO、CO₂、C_xH_y、NO_x及PM_2.5的排放因子.结果表明:①乔木树种不同器官燃烧释放的烟气中颗粒物排放因子存在差异，其中，在不同燃烧状态下CO、PM_2.5、C_xH_y、NO_x的排放因子表现为叶 > 枝 > 皮，CO₂排放因子表现为叶 > 皮 > 枝.②8种乔木明燃下CO、CO₂、C_xH_y、NO_x、PM_2.5的排放因子平均值分别为（176.52±25.40）（1 250.32±168.04）（32.82±8.68）（2.53±0.71）（15.59±5.36）g/kg，阴燃下分别为（250.44±37.43）（1 062.11±145.95）（44.82±9.97）（1.92±0.57）（22.56±7.28）g/kg.CO、C_xH_y、PM_2.5的排放因子呈阴燃>明燃的排放特征，且大部分乔木树种的CO、C_xH_y、PM_2.5排放因子在不同燃烧状态下差异显著.③不同乔木树种燃烧烟气的颗粒物排放因子存在差异，其中CO、CO₂、C_xH_y、PM_2.5的排放因子均呈针叶树种>阔叶树种的特征，NO_x排放因子表现为阔叶树种>针叶树种的特征，但针、阔叶树种之间差异不显著.④不同燃烧状态下，叶燃烧产生的污染物浓度与其元素含量呈显著正相关，且阴燃状态下3种器官的CO排放因子均与自身碳元素含量呈显著正相关.研究显示，不同可燃物类型和燃烧状态对乔木燃烧释放烟气及颗粒物均有影响，不同器官之间燃烧排放特性存在一定差异，且乔木元素含量对其燃烧释放气体污染物的排放因子具有一定影响. 

Characteristics of Smoke and Particulate Matter Released by Combustion of Eight Main Tree Species in Yunnan Province

The emission characteristics of smoke and particulate matters of eight common tree species in Yunnan Province (Cyclobalanopsis glaucoides, Lithocarpus mairei, Alnus nepalensis, Pinus armandii, Acacia farnesiana, Quercus acutissima, Quercus variabilis, Keteleeria evelyniana) were investigated by using smoke analyzer, particulate analyzer and combustion simulation device. The investigation provides fundamental data for the pollutant estimation of large-scale forest fires. The emission factors (EF) of gaseous smoke (CO, CO₂, C_xH_y, NO_x) and particulate matter (PM_2.5) released under different combustion conditions (smoldering/flaming) were measured and analyzed. The results showed that: (1) The pollutant emission factors of different organs of the same tree species were different. For example, the emission factors of CO, PM_2.5, C_xH_y and NO_x were leaf > branch > bark, and CO₂ was leaf > bark > branch. (2) The average emission factors of CO, CO₂, C_xH_y, NO_x, PM_2.5 of the eight tree species in the flaming state ranged (176.52±25.40) (1250.32±168.04) (32.82±8.68) (2.53±0.71) and (15.59±5.36) g/kg, respectively. In the smoldering state, they were (250.44±37.43) (1062.11±145.95) (44.82±9.97) (1.92±0.57) (22.56±7.28) g/kg, respectively. In addition, the EFs of CO, C_xH_y and PM_2.5 in the smoldering state were higher than those in the flaming state, while the EF values of CO₂ and NO_x in the flaming state were higher than those in the smoldering state. The emission factors significantly differ between tree species under different combustion states. (3) The emission factors of combustion pollutants of the eight tree species were different. The EFs of CO, CO₂ and C_xH_y emitted by broad-leaved tree species were greater than coniferous tree species, while the EFs of PM_2.5 were on the contrary. Coniferous species were higher than broad-leaved species. However, the differences between coniferous and broad-leaved species were not significant. (4) The content of carbon and nitrogen in the leaves of the tree species was greater than that in the branches. Under different combustion states (smoldering/flaming), there was a significant positive correlation between the pollutant concentration and the element content, and a significant linear relationship was observed between the CO emission factors and the carbon content of the three organs under the smoldering state. The emission of pollutants from the combustion of trees is affected by the combustion states (smoldering/flaming) and the organs of trees, and the element content of the trees has a certain impact on the emission factors.