Efficient Water Disinfection by Hydrodynamic Cavitation

Researchers from the Faculty of Mechanical Engineering of the University of Ljubljana and the National Institute of Biology were the first in the world to show the possibility of the inactivation of viruses by hydrodynamic cavitation – rapid vaporization and recondensation of water as a result of sudden local change in pressure.

Authors: Janez Kosel, Ion Gutierrez-Aguirre, Tanja Dreo, Nejc Rački, Maja Ravnikar, Matevž Dular


The aim of water treatment is to reduce pathogenic microorganisms to the extent where they are no longer harmful to our health. The standard water disinfection procedures are problematic in terms of energy and the environment. As the first in the world, the researchers from the Faculty of Mechanical Engineering of the University of Ljubljana (Janez Kosel, Matevž Dular) and the National Institute of Biology (Ion Gutiérrez-Aguirre, Nejc Rački, Tanja Dreo, Maja Ravnikar) under the mentorship of Matevž Dular showed the possibility of the inactivation of viruses by hydrodynamic cavitation – rapid vaporization and recondensation of water as a result of sudden local change in pressure. 

In the article published in the Water Research journal, the researchers’ aim was to quantify the impact of hydrodynamic cavitation on the infectivity of bacteriophage MS-2 (model organism, a norovirus dangerous to human health). The results suggest a significant reduction in the number of ineffective MS-2 type viruses – they reached more than 4 log reductions of viral infectivity, thus achieving the threshold of disinfection as prescribed by the EPA (Environmental Protection Agency). The research opens the possibility to a new energy-efficient water disinfection methodology. The editors and reviewers of the magazine labelled the article as a historical milestone and a potentially revolutionary water disinfection technology. It was also placed among featured publications by the International Water Association (IWA). 

In addition to the research, in the past years the group from the Faculty of Mechanical Engineering of the University of Ljubljana has suggested the possibility of the use of cavitation as an energy-efficient and environmentally-friendly method for removing pharmaceuticals, cyanobacteria, algae, and bacteria. The results were presented in eight review articles and four patents and have been cited more than two hundred times. Also, the successful ERC-CoG grant (CABUM) by Matevž Dular bases on the findings of this work.
 

Source: KOSEL, Janez, GUTIÉRREZ-AGUIRRE, Ion, RAČKI, Nejc, DREO, Tanja, RAVNIKAR, Maja, DULAR, Matevž. Efficient inactivation of MS-2 virus in water by hydrodynamic cavitation. Water research, 2017, vol. 124, pp. 465-471. (Category: 1A1 (Z, A'', A', A1/2), (IF = 6.942); ZR – water resources: 1/88, IH – engineering, environmental: 2/49, JA – environmental sciences: 8/229)