Development of Capacitive Deionization Technology for Point-of-Use Water Purification

Development of Capacitive Deionization Technology for Point-of-Use Water PurificationIntegrated Water Management

ABOUT THE PROJECT

This research project seeks to develop a new CDI (Capacitive Deionization Technology) water purification system for point-of-use applications and replace the widely used, but very inefficient Reverse Osmosis units.

NOTABLE ACHIEVEMENTS (November 2016)

• Researchers have designed the water purification system and have worked closely with industry partner to procure the necessary components for the design of a working prototype.

PROJECT UPDATE (April 2016)

Researchers have procured electrode materials and the necessary equipment for electrode fabrication and characterization. A CDI unit has been ordered from a commercial supplier and a plan for the experimental setup for CDI prototype testing has been developed.  Researchers also collaborated with industry partners in India established closer linkages.

RESEARCH ABSTRACT

Reverse Osmosis (RO) is currently the most established and popular technology for the reduction of Total Dissolved Solids (TDS) from water. However, the residential and community based RO technologies have the recovery of about 20-25%, resulting in the wastage of about 75-80% of water. Hence, there is a global need to develop a more feasible and effective technology which reduces the wastage of water, while providing high quality potable water.

Capacitive Deionization (CDI) Technology is an incipient technology that offers a solution to this problem. In CDI, the hard water flows through the oppositely charged electrodes, held at a potential difference of 1.2V. The negative electrode attracts the cations and positive electrode attracts anions. In this process, the water recovery rate will be nearly 50%.

This research aims to develop and evaluate a CDI based water purification system for point-of-use applications. It involves some fundamental work focusing on understanding and optimizing the electrosorption process of ions, evaluating and improving the selectivity and sorption capacity of various ionic species, developing new along with evaluating alternative nano materials (e.g., grapheme and carbon nanotubes) as electrode materials, and studying the potential fouling and/or scaling of the electrodes caused by the water constituents. The results from the bench scale investigation, to be carried out in Canada, will form the basis for prototype / product development work and field testing of prototypes in India through lose collaboration with Eureka Forbes Ltd. The technology will ultimately be incorporated in the design of residential or community Water Purifiers, which can be sold to customers worldwide. These systems will provide safe drinking water with decrease wastage, high efficiency, and lower maintenance requirement.