真空热解工艺参数对生物油产率的影响研究

Influence of Process Parameters on Bio-oil Yield by Vacuum Pyrolysis

以油菜秸秆为原料,采用真空热解系统作为生物质热解液化试验装置,以热解终温、体系压力、升温速率和保温时间为试验因子,生物油产率为试验指标,在单因素试验的基础上,采用响应面法对生物油产率进行进一步优化,利用Design Expert 8.0.6软件分析得出生物油产率的二次多项式模型方程,对热解工艺参数进行寻优,并对优化结果进行了试验验证。研究结果表明,热解终温、体系压力和升温速率是影响生物油产率的主要因素,而保温时间对生物油产率的影响较小;最佳热解工艺参数为:热解终温494.0℃,体系压力5.0 kPa,升温速率18.4℃/min,保温时间60.0 min,在此条件下,生物油产率可达43.50%,与预测值43.63%较为接近。

Rape straw was treated by vacuum pyrolysis for bio-oil preparation. The pyrolysis temperature, system pressure, heating rate and holding time were chosen as input factors, the bio-oil yield as the output. The response surface methodology （RSM） was employed for the optimization of bio-oil yield based on single factor tests. The Design Expert 8.0.6 software was used to build a second order quadratic equation. The optimal conditions were obtained by using the equation. In addition, confirmation experiments were conducted. The results showed that the pyrolysis temperature, system pressure, heating rate were the main factors for the bio-oil yield, while the holding time was the second factor. Optimal conditions were obtained at pyrolysis temperature of 494.0 ℃ , system pressure of 5.0 kPa, heating rate of 18.4 ℃/min and holding time of 60.0 min. Confirmation runs gave 43.50 % of bio-oil yield, which is comparable to 43.63 % of predicted value.