An Efficient Contact Tank Design for Potable Water Treatment

Year 2018, Volume: 29 Issue: 2, 8279 - 8294, 01.03.2018

Ender Demirel , Mustafa Aral

https://doi.org/10.18400/tekderg.322491

Cited By: 8

Abstract

Bu
çalışmada bir temas tankının içindeki türbülanslı akış ile arıtıcı
konsantrasyonunun hareketinin üç boyutlu sayısal benzetimi ikinci mertebeden
yakınsak bir hesaplama modeli kullanılarak gerçekleştirilmiştir. Arıtıcının
zamanla değişen akım ile karışımı Large Eddy Simulation (LES) türbülans
yaklaşımı kullanılarak modellenmiştir. Temas tankının girişinden enjekte edilen
arıtıcı konsantrasyonunun tankın çıkışındaki dağılımını gösteren Kalma Süresi
Dağılımı (KSD) ve toplam KSD eğrileri kullanılarak temas tankının hidrolik ve
karışım verimlerine ait endeksler belirlenmiştir.  Tank içindeki şaşırtma perdeleri üzerinde
yapılan değişiklik ile temas sisteminin verimi arttırılarak enerji sarfiyatlarının
azaltılabileceği gösterilmiştir. Önerilen yeni perde tasarımı sayesinde temas tankının
hidrolik verimi %44, karışım verimi ise %42 oranında arttırılmış, suyun
iletilmesi için gereken enerji sarfiyatı ise %43 oranında azaltılmıştır. 

Keywords

Temas tankı, içme suyu arıtma, HAD, türbülans

An Efficient Contact Tank Design for Potable Water Treatment

Abstract

In this study, a second order accurate Large Eddy
Simulation (LES) model is used to simulate three-dimensional turbulent flow and
disinfectant transport in a contact tank. The hydraulic and mixing indexes of
the tank are evaluated based on computational tracer studies. It is shown that
the energy consumption rates of the contact tank can be reduced by the use of the
proposed slot-baffle design instead of the conventional baffle system that is used
in these facilities. The proposed slot-baffle design improves the hydraulic
efficiency by 44%, mixing efficiency by 42% and reduces the energy required to
drive the flow through the system by 43%. The outcome reported in this study
shows that the energy consumption in water treatment plants can be significantly
reduced when the novel baffle design is implemented on existing contact tanks
without expensive infrastructure modifications. 

 

Keywords

Contact tank, treatment of potable water, CFD, turbulence, LES

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