19 Oct Wastewater and emerging pollutants: exploring the potential of ozone
What are emerging pollutants?
Emerging pollutants are chemicals found particularly in pharmaceuticals, personal care products and pesticides.
They are not yet monitored or regulated, but they are widespread in aquatic ecosystems and raise growing concerns about their potential threat to human health and ecosystems.
What initiatives to address the problem?
This issue is recognized and addressed through European research and regulations, which highlight the hazardous nature of these substances and the importance of protecting water resources, the environment and public health.
The main European legislation in place, Directive 2013/39/EU, sets maximum concentration limits for certain pollutants in open waters to ensure safe drinking water and bathing areas.
Eliminating emerging pollutants through ozone
Wastewater treatment is a priority area of focus for PROAMBIENTE, a laboratory of the Bologna CNR Technopole. Thanks to collaboration with other prestigious research institutions-CNR, ENEA and UNIBO-a scientific study was conducted on the purification of water from emerging pollutants using the innovative Poolsan device, developed by MET, a Bologna-based company with a long history of specializing in ozone-based technologies.
The study examined the efficacy of ozone in water purification using the Poolsan system, a self-assembled device used in wastewater treatment that introduces the gas into flowing water. Ozone dissolved in water induces the degradation of organic molecules through the production of particularly reactive compounds: OH. radicals.
This process is often used in combination with other treatments, such as ultraviolet and ultrasound, depending on the organic content and intended use of the treated water.
The study tested the effectiveness of this method by treating wastewater samples generated locally during agricultural, industrial or civil activities, demonstrating the treatment’s ability to be used even in emergency situations, such as in the absence of drinking water sources due to groundwater pollution or due to interruptions in supply lines.
The results of the study
The experiments successfully removed emerging pollutants in the wastewater. After one hour of treatment, most of the pollutants were completely degraded, with the prospect of even shorter treatment times in the future. Ozone plays a crucial role in initiating oxidative degradation of pollutants, facilitating subsequent biodegradation processes. Comparative analyses using advanced analytical techniques such as HPLC and TOC confirmed the efficiency of this methodology and device.
Long-term evaluations of the treatment effects on micropollutant toxicity were conducted based on the behavior of algae and chemiluminescent bacteria. These analyses confirmed a steady decrease in toxicity compared with pretreatment conditions.
The study evaluated the water sanitization capacity of the device, showing promising results in the gradual reduction of bacterial load.
In conclusion, this study explored the potential of the Poolsan methodology and device in improving water quality. It also anticipated further investigations on bacterial inactivation and organic contaminant abatement.
The methodology’s adaptability and effectiveness make it useful for broader applications, from small isolated communities to emergency situations. Small-scale wastewater treatment along with large treatment plants can greatly mitigate environmental contamination by emerging pollutants and associated public health risks.