The growing need for innovative solutions in sustainable water use affects public water supply, agriculture, and industry alike. The InLEDapp project investigated how novel UV-LED technology can contribute to chemical-free and energy-efficient water treatment (drinking water and wastewater). The aim was to demonstrate the practical feasibility of this technology and compare it with conventional methods.
The project combined laboratory studies with field tests under real-life conditions:
- Drinking water field tests took place in Japan,
- Wastewater field tests were conducted in the Czech Republic.
UV-LED systems from German and Japanese manufacturers were used.
Key Findings:
- The UV-LED systems showed reliable and stable disinfection performance over extended periods, although they performed slightly weaker than a conventional low-pressure mercury system in direct comparison.
- The direct system comparison took place during the wastewater trials in the Czech Republic, where UV-LEDs and conventional UV technologies were operated and evaluated in parallel.
- To study micropollutants, substances were deliberately irradiated with different UV sources on a lab scale to better understand degradation and transformation processes. A complex interaction between UV radiation, organic matrix, and pollutants was observed.
- After completing long-term trials, the systems were thoroughly examined. Deposits were found within the systems, which affected disinfection performance.
- This finding is particularly relevant for maintenance and cleaning: it became evident that biofouling and deposits must be considered not only for conventional systems but also for UV-LED technology.
Conclusion:
The results provide important impulses for the further development and optimization of UV-LED systems – especially in terms of system design, thermal management, cleaning methods, and operational safety. The project was successfully completed and makes a significant contribution to the development of sustainable water treatment systems.
Publications:
Oguma, K. Field demonstration of UV-LED disinfection at small and decentralized wa-ter facilities. Journal of Water & Health, jwh2023192, 2023. https://doi.org/10.2166/wh.2023.192
