Desalinating Produced Water: A Framework for Brine Concentration and Valorization in the Permian Basin

Abstract

Oilfield produced water (PW) in the Permian Basin is projected to exceed 25 million barrels a day by 2030, continuing to pose challenges straining saltwater-disposal (SWD) wells and raising induced seismicity concerns that can constrain production. While recycling it to fracture new wells is progressing well (20% estimated), the vast volume is disposed of via SWD wells. The pore pressure build-up is increasing the risks of induced seismicity (mostly deep disposal) and potential communication to other wells. Simultaneously, West Texas and southeast New Mexico experience chronic drought and water scarcity, creating demand for alternative water sources such as treated produced water. This thesis develops a comprehensive framework grounded in non-ideal thermodynamic modeling, pilot performance data, and navigating evolving regulatory policy for desalinating produced water for beneficial reuse. Produced water volumes and chemistry are characterized, noting extreme salinities (often 100,00 – 200,000 mg/L TDS) and emphasizing the need for robust pre-treatment to remove organic compounds, contaminants, solids, and scale-forming ions. The thesis further evaluates desalination technologies, from advanced membrane processes (e.g., osmotically assisted and low-salt-rejection reverse osmosis) to thermal methods (mechanical vapor compression and humidification-dehumidification), in the context of the Permian Basin’s abundant water, heat, and natural gas resources. Case studies and pilot projects in the Basin demonstrate the viability of achieving high-quality treated water while reducing volume requiring disposal. An integrated framework is proposed for selecting treatment trains and desalination technologies and planning for concentrate management. While disposal by injection is currently cheaper, the strategic use of waste heat, technological innovations, and valorization can shrink the cost gap. Lastly, this thesis explores areas for improvement and recommends future research to further transform a waste challenge into a new water supply and alleviate disposal impacts.