UV-LED for Safe Effluent Reuse in Agriculture

In the face of the water scarcity problem, the use of treated wastewater emerges as a viable alternative to meet the demand of the agricultural sector, the main consumer of available water in the world. Thus, the development of technologies to provide safe wastewater reuse is a priority. We evaluated the reduction rate of the fecal indicator Escherichia coli naturally present in effluent from an urban wastewater treatment plant (WWTP) submitted to UV-LED (Ultraviolet-Light-Emitting Diodes) radiation, emitting UVA (365 and 405 nm) or UVC (255 and 280 nm), used alone or coupled. The 280-nm wavelength seems to be crucial to the success of the disinfection systems, as all the programs that used this wavelength reached a 4-log reduction of E. coli.