UV-C LED and when will it be primetime in wastewater

In the wastewater industry, energy and operation costs are major factors in selection of a disinfection technology. UV-C LED systems are based on a solid-state technology, which generally tends to operate with low electrical consumption and less relative space to conventional UV technology. A comparison of LED UV to UV systems applied to wastewater indicates that there can be large cost savings for this technology as applied to wastewater systems. An UV-C LED pilot study is ongoing at Mill Creek Wastewater Treatment Plant located in Cincinnati, Ohio, USA. This wastewater facility is an activated sludge wastewater treatment plant that is highly impacted by wet weather flows that currently uses hypochlorite for disinfection of the treated effluent. The UV-C LED system would acts as a disinfection step after secondary treatment replacing the hypochlorite system. The main focus of this study is to understand the performance, limitations, and challenges of LED UV in the wastewater environment with aspirations of a future large-scale system. The factors that were examined included disinfection efficacy, energy use, operating cost, and life-cycle cost. The results from the pilot will feed into a municipal system design using UV-C LEDs, decreasing not only the costs and maintenance of the systems but also reduce or eliminate harmful chemical usage. New technologies often begin life at very high cost and low accessibility to some markets. There are often limits in place that prevent fully utilizing newer technology; but, over time costs come down, availability increases and new possibilities open up. Ultraviolet Light Emitting Diode (LED) technology can be seen to follow the same path. This technology has been used for limited applications such as sensors and low-flow water treatment products. It is the premise that advancements in output power and efficiency of UV-C LEDs will see it grow into new markets including city level water treatment. This paper will present an economic case study to answer questions for deploying UV LED technology in the water and wastewater markets.