Third Coast Water Seminar: Integrating Systems for Potable Reuse and Desalination

Dr. Amy Childress delivered this seminar titled, Integrating Systems for Potable Reuse and Desalination: Reduced Energy Consumption for Increased Water Supply. The talk summarized a three-part project that considers synergistic integration of potable water reuse and desalination systems. In the first part, a modeling framework is developed to evaluate combining treated wastewater with seawater reverse osmosis (RO) streams. It was found that potable reuse scenarios, where treated wastewater is combined with intake seawater, lowered energy consumption, seawater intake volume requirements, and discharge volumes compared to scenarios with seawater only as the influent. In the second part of the research, the energy impact of combining RO brine streams and regional brine interceptor/collector streams with wastewater upstream of RO desalination at a potable reuse facility are evaluated. Two scenarios were considered: one that includes seawater inflow and infiltration that is common in coastal regions and one that does not. It was found that the marginal energy consumption of treating high-salinity streams decreases as wastewater salinity increases and that marginal energy consumption is expected to have a decreasing trend in future years. In the third part of the research, noting similarities between treatment processes at seawater RO desalination and potable reuse facilities, the developed framework is being used to consider a future scenario of augmenting a potable reuse facility with seawater to meet potable water demand during peak periods and/or droughts. Alterations that would be required at the potable reuse facility to treat higher salinity feedwater are considered including chemical additions and selection of suitable RO membranes. The benefits of additional water supply of the seawater are weighed against additional energy consumption.

The Third Coast Water Seminars are a monthly research series hosted by Current in partnership with Argonne National Laboratory, Northwestern University, the University of Illinois Urbana-Champaign, the University of Illinois at Chicago, and the University of Chicago. The series is intended to share the latest research in water and water-related technologies/areas of need to spur collaboration and solve pressing water challenges.