生物质半焦气化的反应动力学

REACTIVITY STUDY ON BIOMASS CHARS IN CO_2 ATMOSPHERE

利用热重分析仪研究了CO2气氛下的生物质半焦的反应性。研究发现,所研究的4种生物质半焦都表现出了相同的反应性趋势。其反应性随着转化率的增加而增加。这可能是由于生物质焦样中的碱金属含量,尤其是钾的含量较高的原因。对比生物质气化反应动力学参数研究表明,4种焦样的气化行为可以用收缩核模型来描述,并求出了4种生物质焦样的反应动力学参数。在不同的CO2分压下进行了花生壳焦样的反应性实验研究,发现焦样的反应性正比于反应气体浓度,求出了花生壳焦样的反应动力学方程式。

Using TGA, reactivity of biomass char in CO2 atmosphere was studied. The results showed that, for four biomass chars, the reactivity in CO2 atmosphere has same trend, the reactivity increases with carbon conversion, different from reactivity of coal char in CO2 atmosphere. This result may be due to higher alkali metal content in biomass char than that in coal char. For four biomass chars, the unreacted shrinking core model can be used to describe their gasification behavior. Using the unreacted shrinking core model, the kinetics parameters for four biomass chars were evaluated. Besides, reactivity of peanut shell char in different CO2 partial pressure was also performed. By the above results, gasification kinetics model for peanut shell char was evaluated.