From Toxic Legacies to Sustainable Solutions: The Evolving Science of Industrial Wastewater Treatment

                                          Industrial wastewater-Image credit: deposit photo

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The rise and fall of the Oklahoma town of Picher illustrates the long-term dangers of industrial pollution. Once a booming mining center that supplied much of the lead and zinc used in the First World War, the town was eventually abandoned after contaminated water from thousands of derelict mine shafts caused severe lead poisoning. Its fate underscores the need for safe and effective wastewater treatment, an area that continues to evolve as new risks emerge.
A major concern today is the reliance on filtration membranes made with PFAS, known as “forever chemicals” because they resist environmental breakdown and may pose risks to ecosystems and human health. PVDF, the most widely used membrane material, is a PFAS, and growing regulatory pressure in the US and Europe is driving the search for safer alternatives. Researchers at the University of Bath, led by Olawumi Sadare, are developing a biodegradable, plant-based membrane made from lignin and cellulose. These polymers form a thin charged film on a PES support, enabling the selective removal of both positively and negatively charged pollutants. Early tests show strong performance, with the membrane removing more than 90% of two common dye pollutants. Its hydrophilic nature also helps draw water through while repelling contaminants.
Wastewater challenges vary widely by industry. Mining and manufacturing produce some of the most hazardous effluents, while pharmaceuticals and cosmetics contribute disproportionately to micropollutants in rivers and treatment plant outflow. A USGS study of wastewater from pharmaceutical facilities revealed drug concentrations far higher than in typical treatment plants and confirmed that these contaminants can persist many kilometers downstream. Because most pharmaceutical residues enter waterways through residential wastewater, treatment plants are the critical point of control.
To address this, the pharmaceutical and cosmetics sectors are facing new regulatory demands, including an EU directive requiring producers to cover most of the cost of micropollutant removal. Two treatment approaches dominate: activated carbon and ozonation. Activated carbon can be added as a powder during treatment or applied as a granular medium afterward, while ozonation uses ozone to break down pollutants. Dutch engineering firm Royal HaskoningDHV has created a system called Aurea that combines biological activated carbon filtration with ozonation. By removing many contaminants before the ozonation stage, this combined method boosts efficiency, cuts energy use by up to three-quarters, and extends the life of the activated carbon.
Both the Aurea system and the University of Bath’s plant-based membrane are still progressing through development, testing, and scale-up. Their creators are working with industrial partners and refining performance, reflecting a broader push toward safer, more sustainable technologies in wastewater treatment.