Global Challenges in Water Supply: The Role of Desalination by Forward Osmosis
Friday, April 11th at 1:00 PM to 2:00 PM in 403b Engineering Hall
Speaker: Robert McGinnis (Yale University)
Host: Dr. John Georgiadis and Dr. Menachem Elimelech
Increasing global water scarcity presents a grave challenge to the present and future health, welfare, and prosperity to great numbers of people in both the developed and developing world. This presentation will introduce a novel method of seawater desalination, intended to sustainably augment fresh water supply. Ammonia-carbon dioxide forward osmosis (FO) desalination is a separation process which is driven by the natural flow of water through a semipermeable membrane based on osmotic pressure gradients, rather than through the application of hydraulic pressure to the saline feed stream. Modeling of the total energy demand of FO will be discussed, with a comparison to the energy inputs of conventional desalination processes. Experimental data relates the efficiency of the process to limitations of mass transport in the support structures of membranes as well as to the hydrophilicity of the materials used. Ongoing lab-scale piloting efforts and future field testing will also be presented. Future improvements in membrane design and draw solute removal and recycling methods, as well as the impact of these on the efficiency of FO desalination are considered, as is the long term potential of FO compared to conventional desalination processes.
Robert McGinnis is a PhD candidate in the Environmental Engineering program at Yale University. Rob’s research interests include seawater and brackish water desalination, impaired and waste water treatment, and sustainable power production from renewable sources. He focuses on the design, characterization, and development of engineered osmotic systems, including forward osmosis, pressure retarded osmosis, direct osmotic concentration, and osmotic engines designed for the conversion of low quality heat to power. His work on a novel ammonia-carbon dioxide forward osmosis has progressed to the lab piloting stage, with funding from a consortium composed of the Office of Naval Research, NAVSEA, U.S. Army TARDEC, U.S. Bureau of Reclamation, and NASA, as well as by continuing funding from WaterCAMPWS. Rob was the recipient of the National Science Foundation Graduate Research Fellowship in 2006 and the 2008 ACS Graduate Student Award for Environmental Chemistry. He is the author of seven papers and six patents in the field of engineered osmosis.