(559q) Produced Water Purification By a Vacuum Flow-through Evaporation

The costs of treating produced water typically outweigh the costs of injection, and as a result 91% of produced water in the United States was disposed of via reinjection. The expansion of oil and gas production and water intensity of hydraulic fracturing methods has increased both the demand for new water supplies and the generation of produced water. The majority of the produced water is disposed of by deep well injection, but recent studies have determined that this induces seismicity. There is a critical need to identify alternative approaches for management of produced waters throughout the United States.

In this work, we demonstrate significantly enhanced water flux and ion rejection rate in ZnO deposited membranes by a vacuum flow-through evaporation. ZnO was deposited on macroporous alumina membranes via atomic layer deposition (ALD) to improve water flux by increasing their hydrophilicity and reducing mass transfer resistance through membrane pore channels. The interaction between ZnO ALD layer and water molecules enhanced water flux and ion rejection rates. Compared to uncoated pristine membranes, it was found that ZnO ALD membranes substantially improved water flux while keeping excellent salt rejection rate.