Microfiltration of Mixed Microorganism and Protein Solutions

• Published in: KAGAKU KOGAKU RONBUNSHU Vol. 18; no. 5; pp. 677 - 683
• Main Authors: Miwa, Tan, Nakao, Shin-ichi, Matsumoto, Yutaka, Totsuka, Yoshiyuki, Kimura, Shoji
• Format: Journal Article
• Language: Japanese
• Published: Tokyo The Society of Chemical Engineers, Japan 1992; Kagaku Kōgaku Kyōkai
• Subjects: Baker's Yeast; Bovine Serum Albumin; Cake Layer; Cross-Flow Filtration; E. coli; Membrane Separation; Microfiltration; PMMA; Specific Filtration Resistance
• ISSN: 0386-216X; 1349-9203
• DOI: 10.1252/kakoronbunshu.18.677

Cross-flow filtrations of model suspensions including microorganisms and protein were carried out with polymer microfiltration membranes. Bovine serum albumin (BSA) was mainly used as model protein, and three kinds of model microorganisms were employed : baker's yeast, E. coli and PMMA particles. The influence of various operating conditions, specific filtration resistance of cake layer and intermittent driving of the feed pump on permeate flux and solute rejection were studied. In these model suspensions, BSA was gradually rejected with filtration time in the same way. The steady-state flux obtained had an optimum pressure which gave a maximum permeate flux, and was hardly affected by feed concentration. A cake layer of microorganisms, which had a large permeate resistance, was formed on the membrane surface. This layer was subject to compaction with operating pressure, and its specific filtration resistance was the largest in the E. coli model suspension. It was also found that intermittent operation of the feed pump was very effective in restoring the membrane permeation rate.