Vol.:(0123456789) 1 3 Chemical Papers https://doi.org/10.1007/s11696-019-00694-0 ORIGINAL PAPER Design and optimization of open‑channel water ultraviolet disinfection reactor Tipu Sultan 1  · Zeshan Ahmad 1  · Khazar Hayat 2 Received: 6 June 2018 / Accepted: 21 January 2019 © Institute of Chemistry, Slovak Academy of Sciences 2019 Abstract Design and optimization have developed gradually from a methodology for academic attraction into a technology that has made a signifcant impact on the industrial growth. A careful and well-optimized design of open-channel water ultraviolet (UV) disinfection reactor ensures the achievement of minimum UV dose required, as well as allowing the minimum opera- tional costs. Such UV reactors are mostly utilized in water treatment plants throughout the world to provide the system for disinfecting the drinking water. Yet, at present, lack of rigorous quantitative understanding of behavior in such reactor geometries is shown to limit the versatile and efcient optimization of UV reactor. A new UV reactor design concept is essential that should be able to consider the three signifcant parameters, namely: uniform UV light propagation within the open-channel UV reactor, providing optimum lamp positioning within the volume of the UV reactor and should allow optimum fow rate of the water. It is approved that computational fuid dynamics (CFD) simulation can be used as a quick and cheap means for design and optimization of water disinfection UV reactor. A novel design and optimization approach which combines CFD modeling, design of experiment (DOE), response surface method (RSM) and goal-driven optimization (GDO) was presented for open-channel water UV disinfection reactor. This methodology includes a heuristic approach from scratch to the fnal optimal solution. The optimal design variables which have the optimum value of the object functions were identifed through proposed methodology. The results showed that the CFD method can be employed for estimation of the optimum design, even though the shape of the open-channel UV reactor is complex. The CFD results reveal that the UV dose distribution and fow of water were largely dependent on the lamp positioning. This paper demonstrates that UV reactor optimization in conceptual design is possible using a commercial CFD package. As a conclusion, the proposed design and optimization technique based on DOE, RSM and GDO could be a suitable technique prior to a fnal design of open-channel water UV disinfection reactor. Keywords CFD · Fluence rate · Open-channel · Optimization · Reactor design · Water disinfection Introduction Water is important pillar of life and with the passage of time, water resources are rapidly depleting. Water is important not only for human being but also for all other living things. Water resources are getting polluted due to industrial and human activities. There is dire need to preserve the water resources, to discover better water treatment processes and to optimize the existing treatment processes. Water disinfec- tion using ultraviolet (UV) light is an emerging and prom- ising technology/water treatment process. UV disinfection is also named as green technology due to the absence of disinfection by products (DBPs). Koutchma et al. (2004) investigated that the inactivation of the pathogens is Reyn- olds number dependent: higher the Reynolds number, higher Electronic supplementary material The online version of this article (https://doi.org/10.1007/s11696-019-00694-0) contains supplementary material, which is available to authorized users. * Tipu Sultan sultan.sindhu@gmail.com 1 School of Engineering (SEN), Department of Mechanical Engineering, University of Management and Technology, C-II Johar Town, Lahore 54770, Pakistan 2 Mechanical Engineering Department (Old Campus), The University of Lahore, 1-KM Raiwind Road, Lahore, Pakistan