Eawag

The biologically active, slow-flow sand filters of lake water treatment would remove nanoplastics from the raw water very efficiently. This was shown both in the laboratory and in larger, realistic tests and modelling.

What has been a purification process in wastewater treatment plants for decades can also be used decentrally or semi-centrally as a recycling process for nutrients. Early separation of "solid and liquid" plays a key role here. It allows for flexible solutions in terms of process technology, especially in the treatment of urine. New studies also show that the processes can be used not only for human urine, but also for that of cows or pigs.

Ozonation is an established treatment process to remove micropollutants from wastewater. However, since unstable toxic reaction products can be formed in the process, biological post-treatment is necessary. Results from the Ecotox Centre and Eawag show how well different post-treatment methods reduce ecotoxicological effects. The combination of ozonation and activated carbon proved to be the most effective.

Eawag researchers are using computer algorithms to predict the toxicity of chemicals to fish. Machine learning can help set priorities for experiments and, in the longer term, enable a tremendous reduction of animal testing.

Chlorination of drinking water reduces infections – and it changes the composition of the intestinal flora of young children, as a study published recently in “Nature Microbiology” shows. The results indicate that the diversity of the intestinal flora isn’t reduced and bacteria associated with gut health are increased.

Eawag is taking its experience with the treatment of faecal sludge in low-income countries and applying this know-how in Switzerland. The aim is to develop solutions that allow wastewater to be used as a source of energy and nutrients.