Membrane Ultrafiltration for Suspension solutions of Macromolecules

• Main Authors: Lin Chih Ta, 林志達
• Other Authors: Cheng Tung Wen
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/59600715837690597121

碩士 === 淡江大學 === 化學工程學系 === 89 === In ultrafiltration systems , permeate flux is influenced by the formation of concentration polarization and membrane fouling. Inclination of membrane can enhance the permeate flux in a tubular membrane ultrafiltration system. In this study, the flux behavior in an inclined dead-end or flat-membrane cross-flow ultrafiltration system was investigated. The tested equaous solutions in the experiments were composed of Dextran T70 and Dextran T500. The operating parameters included composition, feed concentration, cross-flow velocity and inclination angle. The gas-liquid two-phase ultrafiltration system was also investigated. Increasing the cross-flow velocity will enhance the permeate flux but decrease the time required for reaching steady state. Under low liquid flow rates, the filtrate resistance is maximum at 00 inclination, get minimum at 1800 inclination. The effect of inclination on the flux is insignificant when operating at the high liquid flow rate. Under high liquid flow rates, the introduction of gas will further enhance the permeate flux when the membrance is at 1800 inclination. The compressible cake model with considering the resistance of concentration polarization layer and the effect of osmotic pressure was applied to calculate the permeate flux for dead-end ultrafiltration. Theoretial results agree with the experimental data, at a little under-estimation.