Development and Optimization of Capacitive Deionization for Treatment of High-Strength Agricultural Waters

Wednesday, 4 October 2017
National Harbor 10 (Gaylord National Resort and Convention Center)
J. Orangi (Auburn University), D. Blersch (Biosystems Engineering, Auburn University), E. Davis (Materials Engineering, Auburn University), P. Chen, and M. Beidaghi (Auburn University)
Desalination technologies are expected to play an important role in producing clean water in the future, resulting a surge in the research and development of energy efficient and cost effective technologies for desalination of seawater and brackish water. Membrane-based desalination technologies such as reverse osmosis (RO) are the most commercially used desalination methods for seawater and treatment of agricultural water, but are highly energy intensive and the future development of desalination is dependent on finding more energy efficient technologies. Capacitive deionization (CDI) is an emerging technology for water desalination, and is based on the phenomenon of ion electrosorption. Simple CDI is an energy efficient technology and its applications for desalination of low molar concentration streams, like brackish water, is demonstrated. However, to expand the applications, research is focused on improving the efficiency and salt removal capacity of CDI systems. To this end, the important requirements are finding electrode materials with higher capacities and CDI systems with higher efficiencies. Also, the large-scale application of CDI for personal and industrial applications is dependent on designing CDI systems with potential to be implemented at different capacities and length scales. In this work, we have studied the CDI for removal of salt and nutrients from agricultural water. Various high surface area electrode materials were considered and the efficiency of CDI for removal is measured via downstream analyses on batch experiments and reported, allowing development of preliminary parameters for optimizing CDI systems for high-strength agricultural wastewaters.