A hot filter was added to a 1 kg/h bench-scale continuous bubbling fluidized bed system for the fast pyrolysis of Chinese fir to get bio-oils. The effects of hot filter on the yield and stability of bio-oils were studied. The results indicated that both the yields of pyrolysis oil ( without hot filtration ) and filtered oil ( after hot filtration ) increased with the increase of pyrolysis temperature,and decreased after 475 ℃,at which the maximum yields were 58. 1% and 50. 7%,respectively. The addition of hot filter resulted in lower oil yield ( approximate 5% -10% decrease) ,which became worse when pyrolysis temperature increased. Compared to the pyrolysis-oilⅠ,the water content of filtered-oilⅠincreased from 13. 77% to 15. 83%,pH value increased from 2. 18 to 2. 23,and high-heating value decreased from 20. 47 MJ/kg to 19. 53 MJ/kg. However,it also showed significant reduction in solids contents,alkali and alkaline earth metals,and the overall decline was about 75%,which suppressed the happening of self-polymerization in bio-oils. During the aging tests,water content and kinematic viscosity of filtered-oilⅠincreased by 10. 2%and 57. 6%,but the fluctuation was less than that of pyrolysis-oilⅠ. GC/MS analysis of the bio-oils showed that less fluctuation in composition was observed in the filtered-oil Ⅰ. This indicated a positive impact of the hot filter on the quality of bio-oil.%在1 kg/h的小型鼓泡流化床热解反应装置中增设一热过滤装置,对杉木快速热解制取生物油进行了研究,考察了热过滤装置对生物油产率和品质的影响。结果表明：热解油(未经热过滤)和过滤油(经过热过滤)的产率随热解温度的升高先上升后下降,并都在475℃时达到最大值,分别为58.1%和50.7%。热过滤装置的引入降低了生物油的产率(下降5%~10%),且热解温度越高,过滤油产率下降越明显。相比于热解油Ⅰ,过滤油Ⅰ的含水率从13.77%增加到15.83%,pH值从2.18上升到2.23,热值由20.47 MJ/kg降低到19.53 MJ/kg,但固体含量、碱金属和碱土金属均有显著下降,总体下降约75%,减少了生物油中自聚反应的发生。在老化实验过程中,过滤油Ⅰ的含水率、黏度分别增加了10.2%和57.6%,但较热解油Ⅰ变化幅度小；通过GC-MS分析其组成变化,发现过滤油Ⅰ中各组分含量变化幅度较热解油Ⅰ小,表明热过滤使其中不利反应的发生得到了抑制,稳定性较好,显示出热过滤装置对生物油品质提升的良好促进作用,有利于生物油的储存、运输和使用。
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