What are latest trends in the drinking water sector? Which innovations have made it or will make it into practice? These questions were raised – and answered – at the expert congress of the Swiss Association of the Gas and Water Sector (SVGW). 200 practitioners from the Swiss water sector discussed technologies and options for water quality monitoring. Attendees represented utilities, engineering companies, consultancies, water laboratory and authorities
The event was moderated by Richard Wülser, Head of Water Quality Assurance and the Water Laboratory at IWB, the local utility and partner in the AquaNES project
AquaNES opened the session of technical talks with Robin Wünsch presenting the results from the Lange Erlen demonstration site. Deploying UV/H2O2 advanced oxidation pre-treatment it is possible to reduce a range of pharmaceutical and other recalcitrant organic micropollutants before infiltrating the water into the aquifer.
As many utilities rely on bank filtration or managed aquifer recharge via soil infiltration for augmenting their groundwater resources, similar processing – yet using ozone – are already implemented into water treatment flowsheets of Swiss utilities. They come into play where source water is impacted or potentially at risk of being affected by industrial activities or damages from urban activities, e.g. traffic or landfills. In some occasions, they are indeed applied in combination with natural pre- or post-treatment processes.
Membranes also can play a crucial role in treatment trains. This is partly due to the specific mix of the water production pattern in Switzerland, where in total 40 % of the supplied water is sourced from springs. The quality of those can vary strongly in heavy rainfall events and thus robust techniques able to cope with broad ranges of intake water qualities are wanted.
The application of membranes was exemplified with two cases from Swiss utilities and the findings from the AquaNES demonstration site Tiefwerder in Berlin. Jeanette Jährig of Kompetenzzentrum Wasser Berlin could show that the single well application of capillary nanofiltration is possible under anoxic conditions with good removal of micropollutants and ions in the cut-off range of the membrane. The operational challenges, such as cleaning regimes and flux restoration could be solved satisfyingly.
Insights into the behavior of nanoparticles highlighted how treatment processes can be controlled or even tailored to remove them from the water phase. The bene
In Switzerland it is quite common that water suppliers have to blend water from springs, groundwater and surface water. This also implies to pay particular attention to the biological stability of supplied drinking water. The application of techniques such as flowcytometry and microbial water testing kits measuring ATP has made this much easier and faster, delivering results in few minutes.