Desalination Energy Recovery and Brine Management through Pressure Retarded Osmosis

May 2020-June 2023

OVERVIEW

Reverse osmosis (RO) based desalination is a process that involves desalting saltwater to create drinking water. While hailed as a solution to drought-stricken regions, utilities have been tentative to adopt desalination due to its high energy costs and the potential environmental impacts from brine disposal. Pressure retarded osmosis (PRO) has been suggested as a potential technology to mitigate these issues. PRO works by capturing the potential energy that exists in the salinity gradient between brine and dilute (e.g. freshwater/wastewater) solutions. However, acquisition of a proper dilute solution can pose challenges, as energy is needed to transport and pretreat the solution before it can undergo PRO. In this study, we are analyzing the viability of using PRO as a brine management and energy recovery scheme for desalination. The overall question of this research is how will implementing PRO-based energy recovery and brine management systems affect the overall performance of desalination facilities in terms of energy consumption and environmental impact?

Above is an interactive figure that visualizes how different types of PRO membranes perform both energetically and economically for a potential PRO system that was created for Tampa Bay using Propmod (a PRO process model that we developed). More details about this figure and what it means will be explained in a future publication.

Significance

The objective of this project is to examine the viability of implementing Pressure Retarded Osmosis based energy recovery and brine management systems for both pre-existing and future desalination plants.​

Objectives

• Simulate individual membrane performance under variable foulant loading conditions using computational fluid dynamics.

• Conduct a sustainability assessment on PRO systems.

• Build a bench-scale reactor for experimental validation and testing.

team members

• Josh Benjamin

• Samar Al Mashrafi

• Bruno Fulco Mancini

Products and Publications

• Propmod Process Model: Available on GitHub.

• USF College of Engineering Interview

• Articles (3) in peer-reviewed journal Desalination and Membrane Sciences (See publication list)

Funding

• This project is funded by the U.S. Department of the Interior Bureau of Reclamation’s Desalination and Water Purification Research Program. More details are available here.

Contact

• For inquiries on this project, contact Joshua Benjamin: jab18<at>mail.usf.edu