Improvement of Hydraulic and Mixing Efficiency of Ozone Contact Tanks

Öz

Disinfection costs of drinking water are increasing day by day due to urbanization, population growth and high energy use. Ozone is used as a pre-disinfection method for the disinfection of drinking water in some drinking water treatment plants in Turkey and becoming increasingly common in the world. It is expected that the disinfection process with ozone will become widespread in in the near future. In this study, the hydraulic and mixing efficiencies of the ozone contact tank in a drinking water treatment facility were evaluated by means of numerical simulations. The flow structure was first examined in detail based on the numerical simulation results from OpenFOAM open-source software. Then, Slot Baffle (SBD) and Porous Baffle (PBD) designs were implemented to the tank for the enhancement of hydraulic and mixing efficiencies. Eventually, the hydraulic and mixing efficiencies were assessed based on the tracer simulations for Conventional Baffle (CBD), SBD and PBD designs.

Anahtar Kelimeler

• Ozone contact tank
• Drinking water treatment
• Hydraulic and mixing efficiencies

OZON TEMAS TANKLARININ HİDROLİK VE KARIŞIM VERİMLERİNİN İYİLEŞTİRİLMESİ

Öz

İçme sularının dezenfeksiyon maliyetleri kentleşme, nüfus artışı ve yüksek enerji kullanımı nedeniyle her geçen gün artmaktadır. Ozon ile içme sularının dezenfeksiyonu ön dezenfeksiyon yöntemi olarak ülkemizde bazı içme suyu arıtma tesislerinde kullanılmakta olup Dünya’da giderek yaygınlaşmaktadır. Ülkemizde de yakın zamanda ozonla dezenfeksiyon sürecinin yaygınlaşacağı beklenmektedir. Bu çalışmada, bir içme suyu arıtma tesisinde bulunan ozon temas tankının hidrolik ve karışım verimleri sayısal benzetimler ile değerlendirilmiştir. OpenFOAM açık kaynak kodlu yazılımı kullanılarak gerçekleştirilen sayısal benzetimler ile öncelikle akım yapısı detaylı olarak incelenmiştir. Daha sonra, Üç Yarıklı Perde (ÜYP) ve Gözenekli Perde (GP) tasarımları tank içerisinde uygulanarak akım yapısındaki değişimler elde edilmiştir. Çalışmanın son bölümünde bozunmasız izleyici sayısal benzetimleri ile tankın hidrolik ve karışım verimleri Klasik Perde (KP), ÜYP ve GP tasarımları için ayrı ayrı değerlendirilerek tankın verim artışı değerlendirilmiştir.

Anahtar Kelimeler

• Ozon temas tankı
• İçme suyu arıtma
• Hidrolik ve karışım verimleri

Kaynakça

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