An Efficient Contact Tank Design for Potable Water Treatment

Öz

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. 

Anahtar Kelimeler

• Temas tankı,içme suyu arıtma,HAD,türbülans

An Efficient Contact Tank Design for Potable Water Treatment

Öz

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. 

 

Anahtar Kelimeler

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

Kaynakça

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