对生物絮凝剂产生菌酱油曲霉(Aspergillus sojae)的廉价培养条件进行了探讨,在此基础上利用自制的放大反应器进行了扩大培养生产絮凝剂的研究.结果表明:在摇瓶培养条件下,发酵液对高岭土悬浊液的絮凝率为99.3%;在扩大培养条件下,发酵液对高岭土悬浊液的絮凝率为99.6%,对多种实际废水也具有良好的絮凝效果,其中处理染织厂废水的综合效果最好,对COD、色度、浊度的去除率分别为68.5%、96.2%、95.8%.考察了发酵液对Cr(Ⅵ)的还原作用,并对还原条件及其性能进行了系统研究.结果表明:生物絮凝剂对Cr(Ⅵ)具有良好的还原作用,处理低浓度含Cr(Ⅵ)废水时还原率>90%.初步推断Cr(Ⅵ)的还原主要依赖于酱油曲霉体内合成并分泌到体外的溶解性还原酶.
The low-cost conditions of cultivating bioflocculant producing strain Aspergillus sojae were studied. On this basis, the scale-up cultivation of the bioflocculant in the self-made reactor was also studied. The experimental results show that when dealing with Kaolin clay suspension, the flocculation ratio of the bioflocculant is 99.3% under bottle-shaking culture and 99.6% under scale-up condition, and the fermentation broth has good purifying effect in the treatment of various wastewaters. Especially in the treatment of yam-dyed wastewater, the satisfactory effect is achieved with the removal rates of COD, chroma and turbidity of 68.5%, 96.2% and 95.8% respectively. The experiment of Cr( VI ) reduction using fermentation broth was also carried out. The factors affecting reduction rate such as pH, reaction time, Cr(Ⅵ) concentration and other coexisting ions were studied. The experimental results indicate that the fermentation broth has a good reduction efficiency and the reduction rate of treating Cr(Ⅵ) solution with low concentration is above 90%, and soluble enzymes which are produced and secreted to the outside of the cell of Aspergillus sojae appear to be responsible for the reduction.