Vibrating membrane filtration as improved technology for microalgae dewatering

• Microalgae membrane filtration is highly improved with vibratory technology.
• Fouling is notably reduced by using shear enhancement.
• Tests at laboratory and pilot scale have been performed.
• Several commercial polymeric membranes and two microalgae species were tested.
• Dynamic membrane filtration reduces cost compared with conventional one.

The effect of shear-enhanced filtration by vibratory process in microalgae dewatering is presented in this paper. The aim of this research was to investigate the technical performance and improvement of vibrating membrane filtration compared with conventional tangential cross-flow filtration in microalgae concentration.An industrial-scale available commercial set-up was used. Several membrane materials as polyethersulfone, polyacrylonitrile, etc., and mean pore sizes (from 7000 Da to 0.2 μm) were tested and compared in both filtration set-ups. Experiments were carried-out with Nannochloropsis gaditana and Phaeodactylum tricornutum microalgae.It has been demonstrated that, even if the choice of the membrane depends on its cut-off, its material and the type of microalgae filtrated, dynamic filtration is always the best technology over a conventional one. If with conventional filtration permeability values were in the vicinity of 10 L/h/m2/bar in steady state phase, with dynamic filtration these values increased to 30 L/h/m2/bar or more.