Microfiltration of beer yeast suspensions through stamped ceramic membranes

The possibility of permeate flux enhancement based on the surface modificat ion of a membrane was investigated. Crossflow microfiltration of a pure bee r yeast suspension through smooth and stamped ceramic membranes was perform ed. The stamped membrane had a helical reversed thread to increase turbulen ce in the feed flow. Both membranes had an outer diameter of about 9 mm, th e same zirkonia oxide active layer with a mean pore size of 0.23 pm. Membra nes were produced by LMPM ENSCM. Fluxes of permeate were measured for diffe rent crossflow velocities and concentrations. A ceramic membrane with a hel ically stamped surface has several advantages compared with a smooth membra ne: flux, as well as limiting flux, are higher at the same velocity of the feed, power consumption per unit volume of permeate is lower for the stampe d membrane and increases with increasing crossflow velocity of the feed. Mo delling of the flux decline indicates different mechanisms of fouling for s mooth and stamped membranes. (C) 2001 Elsevier Science B.V. All rights rese rved.