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http://dx.doi.org/10.4491/KSEE.2017.39.12.706

A Study on Applicability of Coagulant Mixer and Flow Analysis of the Non-powered Vortex Mixer using CFD  

Kim, Soo Yeon (Department of Civil & Environmental Engineering, Hanbat National University)
Chae, Jong Seong (Department of Civil & Environmental Engineering, Hanbat National University)
Kim, Sin Young (Department of Civil & Environmental Engineering, Hanbat National University)
Zhang, Meng Yu (Department of Civil & Environmental Engineering, Hanbat National University)
Ohm, Tea In (Department of Civil & Environmental Engineering, Hanbat National University)
Publication Information
Journal of Korean Society of Environmental Engineers / v.39, no.12, 2017 , pp. 706-713 More about this Journal
Abstract
This study compared and analyzed the water treatment efficiency and the applicability of water treatment plant using the existing Mechanical Rapid-Mixer by introducing the Non-powered Vortex Mixer to the domestic water treatment plant. For this study, fluid flow characteristics and head loss of a Non-powered Vortex Mixer are calculated by Computational Fluid Dynamics (CFD)respectively. The head loss rate inside the mixer was 11.30% when the inflow velocity was 0.5 m/sec, 16.27% at 0.6 m/sec and 21.44% at 0.7 m/sec, the head loss rapidly increased at the optimal velocity of 0.5 m/sec. For the inflow velocity of 0.5 m/sec, the turbulent intensity at the inlet was 2.37% and at the outlet was 7.83%, so there was sufficient mixing strength for the particulate matter and the coagulant. The result of the water quality of the treatment plants with the inflow velocity of 0.38 m/sec that was operated in three years after replacing all 12 units of the existing Rapid-Mixer with the Non-powered Mixer met the standards. Hence, it is possible to reduce the energy consumption of 64,143 ~ 65,306 kWh/year since the Rapid-Mixer is replaced by the Non-powered Vortex Mixer.
Keywords
Non-powered Vortex Mixer; Water Treatment Efficiency; Computational Fluid Dynamic (CFD); Head Loss Rate; Turbulent Intensity;
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Times Cited By KSCI : 1  (Citation Analysis)
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