鸡粪热解特性与动力学分析

Behavior and Kinetics Analysis on Chicken Dung Pyrolysis

应用同步热分析仪,以不同升温速率对鸡粪进行热解,研究其热解特性和动力学。结果表明,鸡粪热解可以分为5个阶段,随着升温速率增加,反应的特征温度和最大失重速率变化较明显。根据Malek法确定热解机理为随机成核和随后成长,把试验数据代入热解鸡粪热解反应式拟合计算得到的活化能和频率因子,与Ozawa法计算的结果相同,确定活化能E为180.83 kJ/mol,频率因子lgA为14.27 s-1,反应级数n为1/3。通过常规热解试验,分析样品在一定温度的固体产率,得到的结果与热重试验的数据接近,验证了热重分析结果的可靠性。

The thermochemical characteristicsand kinetics of chicken dung were studied on thermogravimetric apparatus at different heating rates. It was showed that five steps were included in the pyrolysis process of chicken dung： losing water, pre-pyrolysis, main pyrolysis, second pyrolysis and carbonization. As heating rate increased, the most weight loss rate increased greatly, and the characteristic temperature became higher. With Malek method,reaction model could be determined, which indicated that pyrolysis mechanism of chicken dung was random nucleation and later growth. As the activation energy and frequency factor were estimated by bringing into pyrolysis reaction, the results were similar with the consequence calculated by Ozawa method, which showed that activation energy E was 180.83 kJ/mol, frequency factor lgA was 14.27 s-~ and activation series n was 1/3. By conventional pyrolysis experiment and analyzing the solids product ratio at the certain temperature, the result was in accordance with the residual carbon from TG test, which proved that result from TG test was reliable.