高温液态水法水解稻秆的试验研究

EXPERIMENTAL STUDY ON RICE STRAW HYDROLYSIS BY HOT LIQUID WATER

以广州郊区的稻秆为原料,利用自行设计的小型反应器,以高温液态水的预处理方法,考查了反应时间、温度、压力、液固比、搅拌转速以及预热时间对稻秆水解的影响。实验结果发现:在200℃,压力为4.0MPa,液固比为20∶1,搅拌转速500r/min,预热时间为40min时还原糖浓度达到最大值,还原糖转化率为51.85%,原料转化率达到48.18%。通过范氏分析及扫描电镜对此工况下的水解残渣进行了分析,发现半纤维素水解率达到88.90%,预处理后的原料疏松,孔隙增加,因而能够较大程度地提高后续纤维素酶水解的效率。

Rice straw is one of the most abundant agricultural residues in south China without effective utilization yet. The local rice straw of Guangzhou was chosen as raw materials, the influence factors including reaction temperature, reaction time, pressure, liquid solid ratio, rotate speed and preheating time were investigated with hot liquid water method. The experimental results indicate that the optimal conditions are： 200℃, 10minutes, 4.0MPa, 20：1, 500r/min and preheat- ing 40minutes, in which the reducing sugars yield reaches to 51.85 % and the conversion ratio of raw material is 48. 18%. Then the residue was explored by SEM and van Soest method. It was concluded that the hot liquid water method could be an available way to pretreat the rice straw for downstream enzymy hydrolysis.