How Three Technion Researchers Could Help Save the World’s Water

March 8, 2019

Clean water. We all need it to survive. But 2.1 billion people worldwide don’t have it, and 4.5 billion lack access to adequate sanitation. And more than 840,000 people die each year from water-related diseases. What’s a thirsty world to do?

Various solutions that could positively impact these and other world water woes were presented during the recently held 15th International Conference on Small Water and Wastewater Systems (SWWS) and the 7th International Conference on Resource Oriented Sanitation (ROS), which were co-located at the Technion-Israel Institute of Technology. Among the most compelling presentations were those by three researchers from the Technion Faculty of Civil and Environmental Engineering, who discussed novel techniques for clearing particulate contaminants from water.

Prof. Michal Green, a world renowned water treatment expert, reviewed several innovative methods developed in her laboratory to remove nitrates from water. According to her, “high concentrations of nitrates are the main reason for closure of wells in the coastal aquifer of Israel with a potential for rehabilitation of tens of millions of cubic meters per year.” The various technologies developed in her laboratory, under the management of Dr. Sheldon Tarre, are designed to provide solutions to problems related to the removal of nitrates. These include the removal from brines, which are a by-product of membrane processes, by biological denitrification; removal by ion exchange and bio-regeneration; combination of nanofiltration and reverse osmosis to remove nitrates without brine production; and finally, a closed denitrification radiator with hydrogen as the electrons’ donor, a reactor characterized by high efficiency and very high efficiency of hydrogen.

Prof. Yael Dubowski examined an innovative method for removing organic micropollutants from water: irradiation of the polluted water by ultraviolet (UV) light at extremely short wavelengths. Prof. Dubowski’s research is currently focused on Triclosan, an anti-bacterial substance used in products such as soaps and toothpastes. Its presence in treated wastewater effluent and in freshwater is undesirable. According to Dubowski, “The common solutions for treating micropollutants such as triclosan in water are based, inter alia, on addition of chemicals, which complicates the operation of the system, while we offer a treatment comprising of ultraviolet irradiation only.” Prof. Dubowski and her colleagues are investigating the optimum UV wavelengths for decomposition of triclosan and other organic micropollutants, when irradiating the water with UV light at these wavelengths creates a significant chain reaction that decomposes the micropollutants and disinfects the water. The study was funded by the Volkswagen Foundation and the Lower Saxony State of Germany. Since the system is relatively simple and inexpensive, and does not require the purchase of various chemicals, it is an excellent solution for local (decentralized) treatment units.

Dr. Adi Radian, who deals with environmental chemistry with an emphasis on the development of soil and contaminated water treatment methods, introduced a new technology to remove pesticides from water by combining adsorption and biodegradation. Pesticides are usually present in polluted water at very low concentrations. So low, in fact, that the usual methods of removing them from water are ineffective. The innovative method developed by Dr. Radian is based on encapsulation of bacteria in a gel made of silicon particles. Micropollutants (pesticides, for instance) are adsorbed to the gel that envelops the bacteria and then are degraded by the encapsulated bacteria.

This was the first time that these two conferences, which are part of a series of annual conferences on small water and wastewater treatment systems under the auspices of the International Water Association (IWA) and the Israeli Water Association, were held in Israel. They were organized by Prof. Eran Friedler of the Faculty of Civil and Environmental Engineering at the Technion – Israel Institute of Technology and Prof. Amit Gross of the Zuckerberg Institute for Water Research at Ben Gurion University. Some 200 scientists, practitioners and government officials participated, about one-third from Israel and two-thirds from abroad.

For more than a century, the Technion – Israel Institute of Technology has pioneered in science and technology education and delivered world-changing impact. Proudly a global university, the Technion has long leveraged boundary-crossing collaborations to advance breakthrough research and technologies. Now with a presence in three countries, the Technion will prepare the next generation of global innovators. Technion people, ideas and inventions make immeasurable contributions to the world, innovating in fields from cancer research and sustainable energy to quantum computing and computer science to do good around the world.

The American Technion Society supports visionary education and world-changing impact through the Technion – Israel Institute of Technology. Based in New York City, we represent thousands of US donors, alumni and stakeholders who invest in the Technion’s growth and innovation to advance critical research and technologies that serve the State of Israel and the global good. Over more than 75 years, our nationwide supporter network has funded new Technion scholarships, research, labs, and facilities that have helped deliver world-changing contributions and extend Technion education to campuses in three countries.