The increase in microfibers (tiny synthetic fibers) and harmful bacteria in wastewater poses serious environmental and public health challenges. Researchers led by Professor Milenko Roš and including Professors Jolanda Pikl, Aleksandra Lobnik, Hakim El Khiar and Nataša Uranjek from the University of Maribor, Velenje School of Environmental Protection and AQUA LAB, developed an innovative approach to solve this problem . Their research, recently published in the journal Clean Engineering and Technology, explored a high-efficiency system that combines membrane filtration, a technology that uses thin barriers to separate impurities and a process that uses ozone gas to purify water, a process that uses high-efficiency Reactive oxygen species kill microorganisms.
Ross’s team was motivated by the urgent need to reduce contaminants such as microplastics, the small plastic particles that contaminate water systems, and to treat pathogens in water. Conventional wastewater treatment often fails to adequately remove microfibers and bacteria, which poses a significant threat to aquatic ecosystems and human health. “Our goal is to make the treated wastewater suitable for reuse in the agricultural and recreational industries by eliminating virtually all microfibers, microplastics and microorganisms,” explains Professor Ross.
By using specialized ceramic filters with tiny openings, the team achieved significant results in filtering suspended solids and microfibers. This is followed by a process of purifying the water using ozone gas, a method that uses highly reactive oxygen species to kill microorganisms, where the ozone gas is used to disinfect the water, completely eliminating harmful bacteria, making the treated water ideal for applications such as irrigation and bathing. The study describes a two-step treatment process that goes beyond traditional methods to remove most harmful bacteria by microfiltration alone.
The significance of this innovation lies in its ability to achieve nearly complete removal of contaminants while being adaptable to a variety of wastewater treatment environments. The study utilized a pilot plant system, a small-scale unit used to test and refine industrial processes, to analyze water samples from the Salic Valley wastewater treatment facility. Results showed that the filtration system significantly reduced unwanted particles in the water, while the process of using ozone gas to purify the water, which uses highly reactive oxygen species to kill microorganisms, effectively eliminated remaining pathogens.
Professor Ross and his team have also developed a new system designed to detect microfibers to accurately measure the content of microplastics in treated wastewater. The system uses advanced technology to study materials, providing important insights into the performance of the filtration process. “Microfiltration combined with a process that uses ozone gas to purify water, a method that uses highly reactive oxygen species to kill microorganisms, demonstrates unparalleled efficiency in producing water that meets high safety standards for reuse in a variety of applications, “Professor Ross said.
This innovative system will play a vital role in promoting water sustainability by integrating with a circular economy model, which focuses on reusing resources and minimizing waste, thereby effectively reusing resources . Treated water can support agriculture, reduce freshwater needs, and minimize environmental pollution. Researchers believe implementing similar systems globally could revolutionize wastewater management.
By addressing environmental and public health issues, the research of Professor Ross and colleagues provides a pathway to a more sustainable future. The technology represents a major leap forward in wastewater treatment, ensuring cleaner water for communities and ecosystems.
Journal reference
Rihter Pikl J., Lobnik A., Roš M., El Khiar H., Uranjek N. “Determination and removal of microfibers and coliforms in wastewater treatment wastewater”. Clean Engineering and Technology, 2024.
About the author
Professor Milenko Roš, Ph.D. He has worked at the Institute of Chemistry in Ljubljana for more than 39 years, 25 of them as head of the Water Chemistry, Biology and Technology Laboratory. His work focuses on wastewater treatment, biological treatment plant sludge management, and stoichiometry. As a professor in the field of pollution and water protection, he worked at many domestic institutions (University of Ljubljana, University of Maribor and School of Environmental Protection in Velenje) and at foreign universities (Vienna University of Technology and Warsaw University of Technology). Milenko is the author and co-author of numerous scientific articles, textbooks and more than 15 books on wastewater treatment. In the past, he served as President of the Slovenian Water Protection Society and is an active member of various national and international associations related to water protection and environmental sciences. Milenko Roš is a recipient of the William Dunbar Medal, awarded by the European Water Association for outstanding contributions to the development of applied technologies for wastewater and waste treatment.
Professor Aleksandra Lobnik, Ph.D. In 1998, he received his PhD from the Institute of Organic Analytical Chemistry, University of Graz, Austria. Since 2009, she is employed as Professor at the School of Mechanical Engineering at the University of Maribor. In 2006, she co-founded and served as CEO of IOS Ltd., a spin-off company. In 2021, she became a Slovenian Engineering Academician; she is also the president of the International Sol-Gel Society (ISGS). Participated in more than 50 domestic and foreign research projects as a project manager. Aleksandra Lobnik is also active in promoting science. She is regularly invited to participate on various conference and seminar committees. She has conducted extensive interviews on plastic/textile waste recycling technologies, sensors, nanoscience, knowledge transfer in a wide range of media and roundtables.
Yolanda Ritter-Pickle, MS, The past 18 years have been devoted to exploring innovative solutions for wastewater treatment. Her academic journey began with a degree in environmental protection, followed by a master’s degree in ecological technology at the Velenje Institute of Environmental Protection. She is currently pursuing a PhD at the Maribor School of Mechanical Engineering, focusing on the elimination of microplastics using membrane technology and the use of ozone to disinfect bacteria. As a Master of Ecological Technology from the Ministry of Natural Resources and Spatial Planning, Yolanda leads initiatives to strengthen wastewater collection and treatment infrastructure. Her environmental engineering expertise enables her to make a significant contribution to improving water quality and achieving national and European ecological goals. Jolanda plays a key role in transforming wastewater management and environmental infrastructure through a holistic approach that combines advanced scientific research with effective project management. Her work highlights the potential of innovative technologies to address pressing global challenges related to water scarcity and environmental pollution.
Hakim El-Kiyar, MSc, has been at the forefront of drinking water filtration systems since 1996, dedicated to the development, prototyping and industrialization of innovative filtration technologies. He has also designed effective technologies for purifying drinking water during emergencies and specializes in the recycling of wastewater for various industrial applications. In addition, he has created a microplastic sampling method that can quickly and easily detect microplastics in drinking water. Hakim’s groundbreaking innovations have received several awards from the Slovenian Chamber of Commerce. He has co-authored several research papers and a book on microplastic removal using thin film technology. He has received international patents for many of his products, including non-stop water filtration systems with automatic filter cleaning, continuous water filtration units, portable gravity water filtration units, and various multi-stage water purification systems. Hakim has made significant contributions to water filtration and environmental protection through his extensive work and patented technologies.
Natasha Ulanjek, B.S.graduated in chemical engineering from the Institute of Chemistry and Chemical Technology in Ljubljana. She is the head of the technical and supervisory department of Velenje Utilities Company. Her expertise includes the treatment and quality control of drinking water, as well as the optimization and enhancement of processes for wastewater treatment and biological sludge management. She designs and oversees water treatment and processing facilities as a certified engineer. Natasha has published in academic journals, participated in national and international conferences, and collaborated on various research projects with renowned institutions. She has also received several innovation awards from the Savinja-Šalek Chamber of Commerce and the Slovenian Chamber of Commerce. Natasha has been an active member of the Slovenian Water Protection Association for more than ten years and represents the country in the European Federation of National Water Services Associations. She is pursuing her PhD at the Faculty of Mechanical Engineering at the University of Maribor while working as a senior lecturer at the Faculty of Environmental Protection in Velenje, Slovenia.
