Impact of inner-wall reflection on UV reactor performance as evaluated by using computational fluid dynamics: The role of diffuse reflection

WATER RESEARCH

卷:109

Article

Li, Wentao¹  Li, Mengkai¹  Bolton, James R.²  Qu, Jiuhui¹  Qiang, Zhimin¹ 

[1] Chinese Acad Sci, Key Lab Drinking Water Sci & Technol, Ecoenvironm Sci Res Ctr, Univ Chinese Acad Sci, 18 Shuang Qing Rd, Beijing 100085, Peoples R China

[2] Univ Alberta, Dept Civil & Environm Engn, Edmonton, AB T6G 2W2, Canada

关键词: UV reactor performance;    Inner-wall reflection;    Diffuse reflection;    Fluence rate distribution;    Reduction equivalent fluence;   

DOI  :  10.1016/j.watres.2016.11.068

来源: Elsevier

【 摘 要 】

Making use of the reflected ultraviolet (UV) radiation with a reflective inner wall is a promising way to improve UV reactor performance. In this study, the impact of inner-wall reflection on UV reactor performance was evaluated in annular single-lamp UV reactors by using computational fluid dynamics, with an emphasis on the role of diffuse reflection. The UV radiation inside the reactor chamber was simulated using a calibrated discrete ordinates radiation model, which has been proven to be a reliable tool for modeling fluence rate (FR) distributions in UV reactors with a reflective inner wall. The results show that UV reactors with a highly reflective inner wall (Reflectivity = 0.80) had obviously higher FRs and reduction equivalent fluences (REFs) than those with an ordinary inner wall (Reflectivity = 0.26). The inner-wall diffuse reflection further increased the reactor REF, as a result of the elevated volume averaged FR. The FR distribution uniformity had conditioned contributions to UV reactor performance. Specifically, in UV reactors with a plug-like flow the FR distribution uniformity contributed to the REF to some extent, while in UV reactors with a mixed flow it had little influence on the REF. This study has evaluated, for the first time, the impact of inner-wall diffuse reflection on UV reactor performance and has renewed the understanding about the contribution of FR distribution uniformity to UV reactor performance. (C) 2016 Elsevier Ltd. All rights reserved.

【 授权许可】

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