Filterability of exopolysaccharides solutions from the red microalga Porphyridium cruentum by tangential filtration on a polymeric membrane

ABSTRACTThe red microalga Porphyridium cruentum is exploited industrially for its exopolysaccharides (EPS) and pigments production. EPS produced by P. cruentum are partially released and dissolved into the surrounding environment, they can be recovered from the culture medium after removing the cells. This paper presents a parametric study of the ultrafiltration of EPS solutions on organic membrane. The EPS solutions were produced in conditions representative of an industrial production. They were filtered at lab-scale on a flat, PES 50 kDa MWCO membrane in a complete recirculation mode of permeate and retentate. Permeate flux-transmembrane pressure (TMP) curves were established up to the limiting flux for the filtration of solutions with various values of concentration in EPS (0.10–1.06 kg GlcEq m–3), fluid tangential velocity (0.3–1.2 m s–1) and temperature (20°C and 40°C). The reversible and irreversible parts of fouling were evaluated for each experiment and the critical flux was determined for an int...