• UV-LED Lamps for Sustainability in Water Treatment (REGiREU)

Thursday, 13 May, 2021
IQS Tech Transfer

Image of the pilot reactor equipped with UV-LEDs

REGiREU is one of the projects that has been approved under the RIS3CAT-Agua strategy, in which water plays the leading role, supported by the Government of Catalonia and co-financed by the European Regional Development Fund (ERDF), which has recently concluded.

Research on water regeneration technologies and risk management for reuse have been the priority lines of action for this community, with the idea of replacing the current linear model of water cycle management with another one based on the principles of the circular economy..

IQS has been part of REGiREU, along with leading entities and centres in the water sector, led by researchers from the GESPA Group (Engineering and Environmental Processes Simulation Group) with the IQS School of Engineering, led by professors Dr Maria Auset and Dr Rafael González.

The GESPA Group led the study on replacing mercury UV lamps, traditionally used to eliminate persistent organic pollutants and for water disinfection, with UV-LED lamps that bring multiple advantages: they do not use mercury, they last longer (estimated at up to 100,000 hours), they consume less energy (up to 75% more efficient), and they are smaller in size, enabling design optimization and making them easier to use.

Objectives achieved

By using a pilot reactor, custom designed to be able to reproduce real water purification conditions on a small scale, equipped with a series of UV-LEDs, the researchers have been able to demonstrate the effectiveness of these lamps for disinfection and eliminating persistent organic pollutants in water cycles, specifically polybrominated diphenyl ethers (PBDEs).

• First, these UV-LEDs have optimal performance and provide many more hours of useful life than their predecessors – they have already been in use inside the pilot reactor for three years.

• They enable the definitive elimination of mercury, a major pollutant.

• They start up immediately and do not need to heat up like the previous ones with mercury.

• Finally, these UV-LEDs make it possible to work at several simultaneous wavelengths, and users can choose the wavelength – or combination of them – that best suits the required working conditions. Regarding disinfection conditions and the removal of emerging contaminants, IQS researchers have found that the optimal combination involves working at 225 and 265 nm. simultaneously.