Hybrid Algal-Osmosis Membrane System for Resource Recovery and ZLD Applied to Municipal Wastewater

An algal wastewater treatment process was combined with a hybrid forward osmosis (FO) and reverse osmosis (RO) membrane system to treat urban wastewater, harvest algae for recovering energy and nutrients, and produce potable-quality water from primary settled wastewater. The technical viability of the coupled algal-membrane system was demonstrated through bench and pilot scale studies. Combining RO with an FO system is a promising method to produce potable water. The concentrated algal stream from the FO process can be used for production of biofuels and fertilizer. Anticipated advantages of this algal-membrane system include: energy-efficient wastewater treatment; conservation of resources in wastewater as biofuel energy and nutrients; clean water reclamation through a multiple barrier system; and elimination of waste disposal.