Evaluation of the Efficiency of Ozone Nanobubbles in Wastewater Treatment

• Grant number: 25/12044-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: August 01, 2025
• End date: July 31, 2028
• Field of knowledge: Engineering - Sanitary Engineering - Water Supply and Wastewater Treatment
• Principal Investigator: Renato Falcão Dantas
• Grantee: Michel Alves Branco
• Host Institution: Faculdade de Tecnologia (FT). Universidade Estadual de Campinas (UNICAMP). Limeira , SP, Brazil
• Associated research grant: 24/23386-6 - Evaluation of the Efficiency of Ozone Nanobubbles in Wastewater Treatment, AP.R

Abstract

Ozonation has emerged as one of the most prominent advanced techniques for wastewater treatment due to its ability to remove a wide range of organic contaminants and to promote effective disinfection. This prominence is evident in the increasing number of water and wastewater treatment plants around the world that employ ozonation units. However, the application of ozone in wastewater treatment faces some limitations, particularly its short residence time in solution, which typically lasts only a few minutes.An innovative and promising solution to enhance the performance of ozone in various applications is the use of ozone nanobubbles. These nanobubbles significantly increase the transfer of ozone from the gas phase to the liquid phase, where the treatment takes place. Another important feature of nanobubbles is their relative stability in solution, which allows ozone to remain active for days or even weeks. As nanobubbles gradually collapse over time, they promote the formation of reactive radicals, which further support the treatment process.Nevertheless, there are still several knowledge gaps that need to be addressed in this technology, including: (i) understanding the mechanisms of ozone decomposition and radical formation; (ii) validating ozone measurement methods in the presence of nanobubbles; (iii) accurately assessing the contribution of nanobubbles in the presence of microbubbles; (iv) conducting cost analysis to evaluate the energy demands of bubble production and its economic feasibility, among others.This project is a pioneering initiative aimed at exploring the fundamental aspects of nanobubble technology as well as evaluating its effectiveness in removing micropollutants and disinfecting wastewater, with a focus on effluents from sewage treatment plants (WWTPs). The data generated by this project will undoubtedly be valuable to both scientists and companies working with ozone in water and wastewater treatment. (AU)