滇中地区5种常见树种树皮热解和燃烧的烟密度研究

Smoke Density of Bark Pyrolysis and Combustion of 5 Common Tree Species in Central Yunnan Province

烟是火灾致人伤亡的主要危险因素之一,烟密度对火场能见度、灭火人员生命安全产生重要的影响。为比较不同种树皮烟密度大小差异及含水率、质量对树皮烟密度等级的影响,采用烟密度测定仪对不同含水率、质量的云南松(Pinus yunnanensis)、华山松(Pinus armandii)、直干桉(Eucalyptus maideni)、云南油杉(Keteleeria evelyniana)、栓皮栎(Quercus variabilis)5种树木的树皮进行了热解和燃烧的烟密度测定。结果表明:在质量、含水率相近的情况下,5种树皮在试验期间热解和燃烧平均产烟量由大到小依次为云南松、华山松、云南油杉、直干桉和栓皮栎,针叶树种树皮的热解和燃烧烟密度明显高于两阔叶树种树皮。在质量相近的情况下,随着含水率的增加,华山松、云南油杉、直干桉、栓皮栎树皮的烟密度均呈现先上升后下降的趋势,云南松呈现下降趋势;在含水率相近的情况下,云南油杉、栓皮栎、直干桉树皮的烟密度均随着质量的增加而增加,云南松、华山松树皮的烟密度随着质量的增加呈现先增加后减少的趋势。

Smoke is one of the main risk factors for human casualties caused by fire.Smoke density has an important impact on the visibility of fire site and the life safety of fire extinguishers.In order to compare the effect of moisture content and quality on smoke density of bark,the pyrolysis and combustion smoke density of Pinus yunnanensis bark,Pinus armandii bark,Eucalyptus maideni bark,Keteleeria evelyniana bark,Quercus variabilis bark with different moisture contents and masses were determined by smoke density tester.The results showed that,in the case of similar mass and moisture content,the average amount of smoke produced by pyrolysis and combustion of 5 barks during the experiment from large to small was Pinus yunnanensis,Pinus armandii,Keteleeria evelyniana,Eucalyptus maideni,Quercus variabilis.The smoke density of conifer tree was significantly higher than that of broadleaf tree.In the case of similar quality,with increasing moisture,the smoke density of Pinus armandii bark,Keteleeria evelyniana bark,Eucalyptus maideni bark,Quercus variabilis bark showed a downward trend after the first rise,Pinus yunnanensis bark showed a downward trend.Under similar moisture content,the smoke density of Keteleeria evelyniana bark,Quercus variabilis bark and Eucalyptus maideni bark increased with the increase of the mass.The smoke density of Pinus yunnanensis bark and Pinus armandii bark first increased and then decreased with the increase of mass.According to the carbon formation of the bark during the test,it was suggested that the mass of smoke density test was 2.5 g.