Forward osmosis: Novel desalination of produced water and fracturing flowback

Treatment and reuse of oil and gas (O&G) production wastewater in a cost-effective and environmentally sound manner is critical for sustainable industrial development and for meeting stringent regulations. High salinity, free and emulsified hydrocarbons, silts and clays released from producing formations, and process additives common in O&G drilling wastewater render many conventional treatment technologies ineffective. Forward osmosis (FO) has been established as a promising solution for treatment and desalination of complex industrial streams, and especially for O&G exploration and production wastewaters. FO has achieved up to 85% water recovery from O&G wastewaters and can concentrate feed streams to greater than 150,000 mg/L total dissolved solids. FO can be operated as a stand-alone technology with minimal pretreatment of the feed or can be coupled with other advanced processes such as reverse osmosis (RO). FO minimizes O&G wastewater disposal and can produce clean water for beneficial reuse. Recent developments in membrane fabrication, system configurations, and draw solutions are briefly reviewed.