Hybrid membrane bio-systems for sustainable treatment of oil and gas produced water and fracturing flowback water

Development of unconventional oil and gas (O&G) resources through hydraulic fracturing has surged in recent years. While declines in oil prices have temporarily reduced spending towards research and development of innovative water management techniques, regulations and expected increase in freshwater demand and cost are intensifying competition among treatment providers to develop sustainable and efficient strategies for wastewater treatment and reuse. In this study, biologically active filtration, ultra filtration, and nanofiltration were tested for the treatment of O&G produced water (PW) and fracturing flowback wastewater. Results indicate that with seeding of microorganisms naturally present in PW, a resilient biofilm can develop that effectively removes organic matter from O&G waste streams. This serves as a pretreatment step for subsequent membrane desalination, mitigating membrane fouling. With thorough pretreatment, more than 99% of organic constituents and more than 94% of total dissolved solids can be removed, producing high quality permeate suitable for advanced reuse applications. (C) 2016 Elsevier B.V. All rights reserved.