双螺杆挤压耦合碱预处理对芦苇酶解效果的影响  

Effects of twin-screw extrusion coupled with alkali pretreatment on enzymatic hydrolysis of reed

作　　者：徐佳 张智强 王颖赛 李园 冯昆鹏 周生飞 XU Jia;ZHANG Zhiqiang;WANG Yingsai;LI Yuan;FENG Kunpeng;ZHOU Shengfei(Xiong′an Institute of Innovation,Xiong′an New Area,Hebei 071700,China)

机构地区：[1]雄安创新研究院,河北雄安新区071700

出　　处：《河北科技大学学报》2022年第6期661-668,共8页Journal of Hebei University of Science and Technology

基　　金：河北省重点研发计划项目(22326411D)。

摘　　要：为了提高芦苇中木质纤维素的利用率,减少预处理过程中的能耗、水耗及废水,对双螺杆挤压耦合碱预处理芦苇的工艺条件及酶解效果进行了研究。首先,考察双螺杆螺纹元件、螺杆转速、碱用量、处理温度和保温时间对芦苇酶解效果的影响,对比不同预处理前后芦苇纤维结构和化学组成的变化;其次,通过对预处理后芦苇的逆流洗涤工艺进行优化,分析芦苇的化学组分和酶解得率;最后,采用扫描电镜和傅里叶变换红外光谱仪对预处理前后芦苇的纤维结构进行表征。结果表明:采用双螺杆挤压在KOH用量为4%(质量分数)、温度为90℃、保温2 h、逆流洗涤用水量的固液比(m/v)为1∶8的条件下,能够有效破坏芦苇纤维结构,脱除表面蜡质,木质素脱除率达到72%,预处理后芦苇在较低纤维素酶用量(10 FPU/g底物)下,水解48 h后总糖得率达到0.45 g/g(干芦苇)。因此,双螺杆挤压耦合碱预处理可以提高芦苇酶解转化利用率,工艺过程能耗低、水耗低、无废水排放,为芦苇原料化利用提供了一种低成本、绿色可行的技术方案。In order to improve the utilization of lignocellulose in reeds and reduce the consumption of energy and water and the production of wastewater in the pretreatment process,the technological process conditions and enzymatic hydrolysis effect of twin-screw extrusion coupled with alkali pretreatment of reeds were studied.Firstly,the effects of the twin-screw thread element,screw speed,alkali dosage,treatment temperature and holding time on the enzymatic hydrolysis of reed were investigated,and the changes of the structure and chemical composition of reed fiber before and after different pretreatment were compared.Then,by optimizing the countercurrent washing process of reed after pretreatment,the chemical composition and enzymatic hydrolysis yield of reed were analyzed.Finally,the structure of reed fibers before and after pretreatment was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy.The results show that the twin-screw extrusion under the conditions of 4%KOH treatment at 90℃for 2 h and a solid-liquid ratio of 1∶8(m/v)for counter-current washing could effectively damage the reed fibers structure and remove the surface wax,and the lignin removal rate reached 72%.The total sugar yield of the pretreated reeds reaches 0.45 g/g(dry reed)after 48 h of hydrolysis at a low cellulase dosage(10 FPU/g substrate).Twin-screw extrusion coupled with alkali pretreatment of reed can improve the enzymatic hydrolysis efficiency with low energy and water consumption and no wastewater discharge,which provides a low-cost and green feasible technological solution for the utilization of reed biomass.

关 键 词：生化反应工程 芦苇 双螺杆挤压 预处理 逆流洗涤 酶水解 

分 类 号：X712[环境科学与工程—环境工程]