Abstract:

In order to understand the flocculation and separation processes of fermentation broth and improve the separation efficiency，this paper，at a microscale，examined the influence of shearing force and size of flocs in the flocculation process of fermentation broth on the effect of removing the flocs by filtration.With micronomicin fermentation broth as the research target，the research changed the shearing force on the flocs in the flocculation process.The size and size distribution of the flocs under different shearing forces were measured within 0.02—2000 μm with a laser particle size analyzer.The filtering rate and settling rate of the flocs were determined.The experiment results showed that the size of the flocs decreased with increasing shearing force and the size distribution span of the flocs increased with increasing shearing force.The settling rate of the flocs increased with increasing size of the flocs; under a moderate shearing force，the flocs had a moderate size and size distribution span and a bigger compaction degree，and the filtering rate of the flocs reached a maximum value.The experiment results indicated that the shearing force in the flocculation process evidently affected the size，size distribution span and compaction degree of the flocs and affected the filtering rate and settling rate of the flocs.

Key words:

絮凝体微尺度, 分离, 絮凝, 过滤, 发酵液, 小诺霉素

摘要： 为探索发酵液絮凝分离过程规律以提高分离效率，本文在微观层面上研究发酵液絮凝过程中的剪切力、絮凝体尺度对絮凝体过滤分离效果的影响。以小诺霉素发酵液为研究对象，在絮凝过程中改变絮凝体所受的剪切力，使用激光粒度分析仪在0.02～2000 μm尺度内测定不同剪切力下絮凝体的粒度及粒度分布，并测定絮凝体的过滤速率及沉降速率。实验结果显示：絮凝体的粒度随剪切力的增大而减小，絮凝体的粒度分布宽度随剪切力的增大而增大；絮凝体的沉降分离速率随絮凝体粒度的增大而增大；在适度的剪切力下絮凝体有一适度的粒度及粒度分布宽度和较大的密实度，此时絮凝体的过滤分离速率有一最大值。实验结果表明：絮凝过程中的剪切力显著影响絮凝体的粒度、粒度分布和密实度，从而显著影响絮凝体的过滤速率及沉降速率。

关键词:

絮凝体微尺度, 分离, 絮凝, 过滤, 发酵液, 小诺霉素