İçme suyundan elektrokoagülasyon prosesi ile doğal organik madde giderimi

Yıl 2011, Cilt: 27 Sayı: 4, 309 - 316, 01.08.2011

Fuat Özyonar Bünyamin Karagözoğlu Eyüp Atmaca

Öz

Bu çalışmada içme sularından doğal organik maddelerin (DOM) Elektrokoagülasyon (EC) prosesiyle arıtılabilirliliği incelenmiştir. Bu amaçla Sivas 4 Eylül Barajının sularının arıtıldığı, Sivas içme suyu arıtma tesisi girişinden ham su numuneleri alınmıştır. Arıtma verimliliğinin ölçülmesinde çözünmüş organik karbon (ÇOK) ve UV254 absorbans parametreleri dikkate alınmıştır. Demir ve alüminyum elektrotların monopolar paralel bağlı kullanıldığı EC reaktöründe ÇOK ve UV254 absorbans giderimi üzerine; başlangıç pH, akım yoğunluğu ve elektroliz süresi gibi işletme parametrelerinin etkisi incelenmiştir. Alüminyum elektrotlarının kullanıldığı EC prosesinde başlangıç pH, akım yoğunluğu ve elektroliz süresinin optimum değerleri sırasıyla; 5, 20 A/m2 ve 20 dakika olarak bulunmuştur. Bu koşullar altında, ÇOK ve UV254 giderme verimleri sırasıyla; %78 ve %94,5 olarak elde edilmiştir. Demir elektrotları kullanılması durumunda, optimum işletme koşulları başlangıç pH 6, akım yoğunluğu 20 A/m2 ve elektroliz süresi 20 dakika olarak bulunmuştur, bu koşullarda ÇOK ve UV254 giderme verimleri sırasıyla; %65,4 ve % 80,3’tür. Ayrıca enerji ve elektrot (alüminyum ve demir) harcanımları açısından işletme maliyeti hesaplanarak EC prosesinin ekonomik değerlendirilmesi yapılmıştır. Sonuç olarak EC prosesinin içme sularından DOM gideriminde etkili bir proses olduğu ortaya konulmuştur.

Anahtar Kelimeler

Elektrokoagülasyon, Doğal organik madde, Demir ve Alüminyum elektrot, ÇOK ve UV254giderimi

Removal of natural organic matter from drinking water by electrocoagulation process

Öz

In this study, the treatability of natural organic matter (NOM) from drinking water by EC process was investigated. For this purpose, raw water samples were taken from the influent of Sivas Water Treatment Plant which is treating the water of Sivas 4 Eylül Dam. Dissolved organic carbon (DOC) and UV254 parameters were considered for the evaluation of treatment performance. The effects of various operating parameters such as initial pH, current density and electrolysis time on DOC and UV254 reduction were examined in an EC reactor using monopolar parallel connected aluminum and iron electrodes. The optimum values of initial pH, current density and electrolysis time for the EC process using aluminum electrode were found to be 5, 20 A/m2 and 20 min, respectively. Under these conditions, removal efficiencies for DOC and UV254 were obtained as 78% and 94.5%, respectively. In the case of iron electrode, removal efficiencies of DOC and UV254 were 65.4% and 80.3%, respectively under the optimum operating conditions which were found to be pH: 6, current density: 20 A/m2 and electrolysis time: 20 min. Besides, economical evaluation of the EC process was also made through calculating operating costs in terms of energy and electrode (aluminum and iron) consumptions. As a result, EC process was proved to be an effective treatment method for the removal of NOM from drinking water.

Anahtar Kelimeler

Electrocoagulation, Natural organic matter, Iron and aluminum electrodes, DOC and UV254removal

Kaynakça

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