Forward osmosis with waste glycerol for concentrating microalgae slurries

Forward osmosis of microalgal suspensions was performed by using a dialysis membrane submerged in pure glycerol or a simulated crude glycerol of a biodiesel production process. Freshwater, marine and hypersaline microalgae were concentrated from around 1 to 2.5 g·L− 1 within an hour of treatment with crude glycerol. Cultures of marine microalgae could be osmotically dehydrated using crude glycerol as the draw solution at fluxes of around 2.75 L·m− 2·h− 1. This dewatering method was shown to be reliable and may be used in conjunction with other dewatering methods to improve the overall energy efficiency of a biomass recovery process.