The sweet spot of forward osmosis: Treatment of produced water, drilling wastewater, and other complex and difficult liquid streams Original Research Article

Global water scarcity and substantial challenges associated with treatment of complex and impaired liquid streams have advanced the development of forward osmosis (FO), which can successfully treat and recover water for beneficial reuse. Surging research and advancements in FO, a technology once unable to compete with conventional wastewater treatment processes, have identified its sweet spot: treatment and desalination of complex industrial streams, and especially oil and gas (O&G) exploration and production wastewaters. High salt concentrations, decentralized and transient operations, the presence of free and emulsified hydrocarbons, silts and clays leached from producing formations, and process additives common in O&G drilling wastewater and produced water render many common treatment technologies ineffective. Treatment and reuse of O&G wastewater, and other complex industrial streams, in a cost effective and environmentally sound manner is critical for sustainable industrial development and to meet increasingly stringent regulations. This review focuses on the successful development and demonstration of FO membrane treatment systems, supported by a review of bench-scale, pilot, and demonstration studies on treatment of O&G waste streams, landfill leachates, centrate from anaerobic digesters, activated sludge in membrane bioreactors, and liquid foods and beverages. Recent developments in membrane fabrication, system configurations, and draw solutions are briefly reviewed.