Veysel EROĞLU, Yangın Çiğdem GÖMEÇ

Ilıman bölgelerde düşük kirlilik yüküne sahip atıksuların havasız arıtımı

Etkili hacimleri 6.45 litre olan iki adet Yukarı Akışlı Çamur Yataklı (YAÇY) reaktör, evsel atıksu karakterindeki sentetik su beslenerek, sürekli sistemler olarak çalıştırılmıştır. Mezofilik YAÇY reaktör 35+2.0 °C'de çalıştırılırken psikrofilik (soğuk seven) reaktör başlangıçta oda sıcaklığında çalıştırılmış, daha sonra sıcaklık adım adım 10±2.0°C'e düşürülmüştür. 10±1.0°C ve 35+2.0°C'de, 12 saat hidrolik bekleme süresinde sırasıyla %82 ve %92 civarında KOİ giderimleri gözlenmiştir. Biyogaz üretimleri, $geq$ 16°C'de her iki reaktörde hemen aynı gözlenmiş, sıcaklık 10+1.0°C'e düşürüldükten sonra belirgin bir azalma göstermiştir. Psikrofilik reaktör verimi daha düşük ölçülse bile, düşük kirlilik yükündeki atıksuların havasız arıtımı başarılı şekilde gerçekleştirilmiş, ilave ısıtma ihtiyacı göstermeyerek daha ekonomik arıtım sağlanmıştır.

Anaerobic treatment of low strength wastewaters at temperate regions

In this study, two identical lab-scale Upflow Anaerobic Sludge Bed (UASB) reactors with an effective volume of 6.45 I were used and operated as continuous systems for about 12 months. The mesophilic UASB reactor was operated at ,35+2.0 °C whereas the psychrophilic UASB reactor was operated at room temperature at the start-up and reduced to around 10+2.0°C step by step. In the study, synthetic wastewater characterizing domestic sewage was fed to both reactors. Results indicated around 82% COD removal at 10±1.0°C at a hydraulic retention time of around 12 h while at the same hydraulic retention time total COD removal could be observed around 92% at 35+2.0°C. The total biogas productions were observed about the same amount at temperatures above 16°C in both reactors. However, when the temperature in the psychrophilic UASB reactor was reduced to 10+1.0°C, total biogas production decreased significantly. pH values in the effluent of the mesophilic UASB reactor were measured slightly higher than the pH values in the effleunt of the psychrophilic UASB reactor. Although average COD removals at the psychrophilic UASB reactor was observed lower than the mesophilic UASB reactor, anaerobic treatment of low strength wastewaters could be well established and more feasible system due to no heating requirement could be achieved successfully.

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