模拟生物油分子蒸馏的响应面法工况优化

Condition optimization of simulated bio-oil molecular distillation via response surface method

分子蒸馏是一种高效的生物油分离技术。本文应用刮膜式分子蒸馏装置,对模拟生物油在不同蒸馏温度、蒸馏压力和进料速率下的分离特性进行了研究,考察不同因素对族类化合物蒸出特性的影响。随后采用响应面分析法对模拟生物油分子蒸馏进行了计算机模拟,考察多种因素对分子蒸馏的交叉影响。通过ANOVA分析,模型的F值为21.25,表明模型是显著的。并以目标物酸醛酮在馏分中的质量分数为响应值得到最佳工况:蒸馏温度69.83℃,蒸馏压力1498.31Pa,进料速率5.54m L/min,此时轻质馏分中酸醛酮的质量分数为39.12%。最后在此工况下开展了模拟生物油的验证实验,结果显示馏分中目标物的质量分数为38.96%,与响应面模型吻合良好。模拟生物油经过分子蒸馏后酸醛酮的质量分数由28.50%提升至38.96%,同时酚类的质量分数由37.50%降低到25.14%。

Molecular distillation is an efficient bio-oil separation technology. The wiped-film molecular distillation apparatus was employed to investigate the separation properties of the simulated bio-oil under different process conditions including distillation temperatures,distillation pressures and feed rates,respectively. Then,the response surface method was used to study the effects of multi-factors on the molecular distillation. According to ANOVA analysis,the F-value of 21.25 implied the model was significant. The concentration of the acid,the aldehyde and the ketone in the light fraction was set as the response value and the optimum condition of 69.83℃,1498.31 Pa and 5.54 m L/min was determined. On this condition,the concentration of the acids,the aldehydes and the ketones was as high as 39.12%. Finally,the validation test of the simulated bio-oil was carried out under the optimum condition. The concentration of the target products in the light fraction of 38.96% was achieved,which was highly in accordance with the result from response surface method. The concentration of acid,the aldehyde and the ketone via molecular distillation increased from 28.50% to 38.96%,and the concentration of the phenols decreased from 37.50% to 25.14%.