An investigation on the use of ultraviolet light emitting diodes (UV LEDs) in a plug-flow reactor for water treatment

摘要

In this study, a small bench-scale plug-flow reactor was designed and characterized to demonstrate the feasibility of using UV/LEDs as a UV source in flow-through advanced oxidation processes. The plug-flow reactor was characterized by investigating the effects of residence time, H2O2/methylene blue molar ratio, and initial methylene blue concentration on methylene blue decolorization in water. Methylene blue was selected as a witness dye, because it does not degrade with H2O2 or with UV alone, and it has reduced absorption in the visible spectrum when reacted with OH radicals. UV/LEDs have been employed successfully in AOPs for water treatment in research-scale systems, as demonstrated in this study. However, they currently have low optical output, which limits their applicability for water treatment to small point-of-use systems. (c) 2017 American Institute of Chemical Engineers Environ Prog, 36: 857-863, 2017