The effect of culture salinity on the harvesting of microalgae biomass using pilot-scale tangential-flow-filter membrane

In this study, the effect of culture salinity (4-6% NaCl) on the harvesting of two microalgal strains (i.e., Picochlorum sp., and Tetraselmis sp.) was investigated using pilot-scale TFF membranes. The cultures of these two strains were collected from their respective continuous cultivation in 2, 25,000 L raceway ponds. For both strains, an increase in culture salinity aggravated the membrane fouling and hence negatively influenced the permeate flux rate, biomass concentrating factor, and energy requirement in biomass harvesting. For the TFF membranes, an increase in 1% NaCl salinity, the volume of processed permeate reduced by 30-44 %, the energy consumption per unit volume of permeate increased by 3-63%, and the biomass concentrating factor reduced by 47-61%.