超滤膜技术在L-阿拉伯糖发酵液精制中的应用

摘要

In this paper, the applicability of ultrafiltration membrane(UF) in the purification process of L-ara-binose fermentation liquid was studied. The influence rules of pore size, operating pressure, operating tempera-ture, and cross-flow velocity on the flux of ultrafiltration and downstream procedures (ion exchange) were in-vestigated. The results showed that: the optimum pore size was 1.0 μm;the optimum operating pressure was 0.4 MPa;the optimum operating temperature was 50℃;the optimum cross-flow velocity was 6 m/s;the average flux was 119.8 L/(m2·h). The optimum cleaning condition was hot water(65℃) and chemical cleaners, and the recovery was more than 95%after cleaning. Compared with the classical pad filtration process, UF technology can promote the downstream ion exchange capacity more than 51.45%;which was 68.02%, Compared to the classical rotary drum vacuum filtration process. In conclusion,UF technology can intercept yeast, bacteria, gelatin, protein and pigments and other impurities in Yeast, bacteria, gelatin, protein and pigments and other impurities efficiently;keep downstream ion exchange production running smoothly;increase the quality of L-arabinose product.%为研究超滤膜分离技术在L-阿拉伯糖发酵液精制提纯工艺中的应用，采用超滤膜系统对L-阿拉伯糖发酵液进行分离，从膜孔径、操作压力、操作温度、错流流速4个方面考察了发酵液对超滤膜通量的影响，以及不同过滤方式对后续离子交换树脂工作交换容量的影响。结果表明：选用孔径为1.0μm的超滤膜，控制操作压力0.4 MPa、操作温度50℃、错流流速6 m/s，其超滤膜对L-阿拉伯糖发酵液的平均膜通量为119.8 L/（m2·h）。采用热水（65℃）与化学清洗剂相结合的清洗方式，可使每次超滤膜的膜通量恢复至新膜通量的95%以上。超滤膜分离技术较之板框过滤可使后续离子交换树脂的工作交换容量提高51.45%，较之真空转鼓过滤可使后续离子交换树脂的工作交换容量提高68.02%。综上结果，超滤膜分离技术可以高效地截留L-阿拉伯糖发酵液中的酵母、菌体、胶质、蛋白及色素等杂质，使后续的离子交换工序顺利进行，从而提高L-阿拉伯糖的产品品质。