Postdoctoral Fellow
Department of Mechanical & Industrial Engineering

University of Toronto

Dr Marina Freire-Gormaly is a Postdoctoral Fellow at the University of Toronto in Mechanical Engineering. Her research is on the development of a stand-alone solar powered reverse osmosis water treatment system for remote communities. She has a Masters of Applied Science from the University of Toronto on Carbon Capture and Storage Technology. She was the sole-course instructor of a 4th year undergraduate and graduate level course called "Innovative Technologies and Organization in Global Energy Systems", which explores how engineers influence the complex interlinked energy systems which power our communities. She has worked at Ontario Power Generation on the Darlington New Nuclear Project and the Darlington Refurbishment Project. Marina is the Student Affairs Chair for the Canadian Society of Mechanical Engineers. She is passionate about research, teaching and service to inspire the next generation of engineers to tackle society’s growing water and energy challenges.

Experimental Characterization of Membrane Fouling under Intermittent Operation and Its Application to the Optimization of Solar Photovoltaic Powered Reverse Osmosis Drinking Water Treatment Systems

The World Health Organization estimates that 760 million people worldwide lack access to clean drinking water. The regions with the highest water scarcity are usually off-grid, remote and have high solar insolation. Therefore, the use of solar powered reverse osmosis water treatment systems is a viable solution. However, to minimize the costs, these systems are configured with minimal battery storage and operated intermittently with extended shutdown periods. Literature lacked an experimental characterization of the effect of this intermittent operation on membrane fouling and an associated design optimization framework. 


This work on solar powered reverse osmosis systems is divided into two main parts: (1) the experimental characterization of membrane fouling under intermittent operation, and (2) the development of an analytical membrane fouling model and a design optimization framework for these systems.


A new fully-instrumented experimental lab-scale system was designed, built, commissioned and operated with triplicate measurements of membrane permeability and membrane salt rejection for the experimental characterization. A new pilot-scale experimental system was also designed, built and operated. The membrane fouling was characterized experimentally for intermittent and continuous operation. The effect of anti-scalant and rinsing was also investigated. Membrane autopsy was also performed using scanning electron microscopy.


An analytical membrane fouling model was developed based on the experimental results. Furthermore, a novel design framework was developed using this new analytical membrane fouling model. This design optimization framework can be used for the configuration of community-specific solar photovoltaic reverse osmosis systems that are reliable throughout the system life at a minimal cost.