基于平行反应模型的稻壳生物油燃烧机制研究

Mechanism Research on Rice Husk Bio-oil Combustion Based on Parallel Reaction Model

利用热重–红外联用技术(thermogravimetric-Fourier transform infrared spectroscopy,TG-FTIR)研究稻壳生物油的燃烧过程。基于平行反应模型理论,使用多峰高斯拟合方法分析不同升温速率下稻壳生物油的失重速率曲线,并对燃烧各阶段释放的物质进行红外分析。结果表明,生物油燃烧的失重速率曲线可以描述为6个高斯函数峰的叠加。前3个拟合峰对应轻质有机物的挥发,第4个拟合峰对应重质有机物的分解和缓慢氧化,最后2个拟合峰对应二次焦炭的燃烧。升温速率的提高影响各拟合峰所占份额,加剧生物油挥发,减少二次焦炭生成,但仅对最后2个拟合峰的动力学参数有明显影响。最后结合多峰高斯拟合结果和红外分析结果提出稻壳生物油燃烧模型。

The combustion of bio-oil from rice husk was carried out on a thermogravimetric （TG） analyzer coupled with a Fourier transform infrared spectroscopy （FTIR）. Based on parallel reaction model, multi-peaks Gaussian fitting was utilized to analyze the first derivative curves of weight loss at different heating rates and the evolution of gas released from combustion was investigated by FTIR. The results show that the first derivative curves of weight loss could be described as an overlap of six Gauss peaks. The first three peaks are attributed to the volatilization of light compounds, the forth peak is corresponding to the heavy compounds decomposition, and the last two peaks are characteristic to the burning of secondary char. Higher heating rates affect the share of six peaks, boost the volatilization of bio-oil, decrease secondary char yield, but have no effects on the kinetic parameters of the fitting peaks except the last two. Moreover, a combustion model of rice hunk bio-oil from rice husk is proposed by integrating the results from multi-peaks Gaussian fitting and FTIR.