A New Light UVC-LED for Wastewater Disinfection

The growth of UltravioletC Light Emitting Diode (UVC-LED) systems in the water and wastewater market has been occurring at a geometric. Based on a recent survey (Cosman 2019) the number of vendors providing UVC-LED system has increased from 3 in 2017 to over 18 in 2019. While not all the companies provide systems for water and wastewater applications, the interest and growth of the UVC-LED vendors is occurring at a very rapid pace. The Electric Power Research Institute (EPRI) (2019) estimated the UVC-LED systems would reduce the capital cost of UV systems by 75 percent and the power use by 50 percent in the wastewater industry. Aqua-Aerobic Systems Inc. (Aqua-Aerobic) installed the METWATER UVC-LED unit at its Rockford, Ill test facility. Validation test runs were completed using filtered effluent as well as secondary treated effluent to determine the effectiveness of the unit in treating wastewater. A combination of various test runs were completed to determine the conditions under which the unit could be used to treat wastewater. Based on these results, computational fluid dynamic (CFD) and light intensity modeling was recommended to develop a plan to increase the treatment capacity of the test unit. The procedures for the models have been completed, however the actual runs have not been completed due to issues related to COVID-19. It is anticipated that the results of the model will show that a change to inlet conditions as well as baffling may need to be incorporated into the design of the existing unit to improve its overall effectiveness.