ABSTRACT

The UV-C light emitting diode (LED) has shown numerous advantages over the traditional UV mercury lamp for water sterilization applications. Multi-chip LED array was used to provide sufficient UV fluence for bacteria inactivation in limited time. According to the point light source characteristic of LEDs, the arrangement of LEDs in the batch reactor is crucial to optimize the inactivation efficiency. In this study, the inactivation of Escherichia coli (E. coli) was investigated using the 280 nm UV-C LED array. Input electrical power, chip interspace (L) and distance (D) between the reactor and water surface were analysed in terms of their effects on the inactivation of the microorganisms. An optimal inactivation efficiency of E. coli was obtained under the condition of L = D=25 mm to reach 4.0 log without using a magnetic stirrer. Additionally, the increasing rate of log inactivation of E. coli decreased with input power due to the significant decrease of wall plug efficiency of the UV-C LEDs.

摘要

在水消毒应用中，UV-C 发光二极管 (LED) 显示出优于传统 UV 汞灯的众多优势。多芯片 LED 阵列用于在有限的时间内为细菌灭活提供足够的紫外线通量。根据 LED 的点光源特性，批式反应器中 LED 的排列对于优化灭活效率至关重要。在这项研究中，使用 280 nm UV-C LED 阵列研究了大肠杆菌（大肠杆菌）的灭活。输入电功率、芯片间隙 (L) 和反应器与水面之间的距离 (D) 就它们对微生物灭活的影响进行了分析。大肠杆菌的最佳灭活效率在不使用磁力搅拌器的情况下，在 L = D = 25 mm 的条件下获得了 4.0 log。此外，由于 UV-C LED 的壁插效率显着降低，大肠杆菌对数失活率的增加随着输入功率的增加而降低。