TUZ (NaCl) VE TOKSİK (Cr6+) ŞOK YÜKLEMELERİN ARDIŞIK KESİKLİ REAKTÖRLERDE (AKR) OKSİJEN KULLANIMI VE KOİ GİDERİMİ ÜZERİNE ETKİSİ

Öz

Bu çalışmada; laboratuar ölçekli Ardışık Kesikli Reaktör (AKR) kullanılarak tuz (NaCl) ve toksik (Cr6+) şok yüklemelerinin biyolojik atıksu arıtım verimi üzerine etkisi incelenmiştir. Paralel işletilen 2 reaktörden biri kontrol reaktörü olarak çalıştırılırken diğer reaktöre, 20 g/L NaCl, 5 mg/L Cr6+ ve 10 mg/L Cr6+ şok yüklemeleri uygulanmıştır. Reaktörlerde günlük olarak kimyasal oksijen ihtiyacı (KOİ), karışık sıvıdaki askıda katı madde (MLSS), çamur hacim indeksi (ÇHİ), NaCl ve Cr6+ seviyeleri izlenmiştir. NaCl şok yüklemesi KOİ giderim verimini düşürmüş ancak reaktör 3 gün içinde dengeye gelmiştir. 5 mg/L Cr6+ şok yüklemesinde KOİ giderim oranının düşmüş olmasına rağmen sistem 3 gün içinde normal şartlarına dönerken, 10 mg/L Cr6+ şok yüklemesinde KOİ giderim oranı yine düşmüş ancak toksik madde konsantrasyonunun artması nedeniyle dengeye gelme süresi uzamış ve sistem 5. gün sonunda normal işletme şartlarına dönebilmiştir. Tüm şok yüklemelerde MLSS ve ÇHİ değerlerinde çok önemli bir değişiklik olmamıştır.

Anahtar Kelimeler

• Atıksu arıtımı, şok yükleme, tuz (NaCl), toksik (Cr6+), AKR.

Effects of Salt (NaCl) and Toxic (Cr6+) Shock Loadings on Oxygen Utilization and Carbon Removal in Sequencing Batch Reactor (SBR)

Abstract

In this study, effects of salt (NaCl) and toxic (Cr6+) shock loading on the biological wastewater treatment efficiency were determined by using laboratory scale SBR. For this aim, 2 parallel Sequencing Batch Reactors were used, one was the control and the other was shock loaded reactor. 20 g/L NaCl, 5 mg/L Cr6+ and 10 mg/L Cr6+ shock loadings were applied to one of the reactors. COD, MLSS, SVI, salt (NaCl) ve Cr6+were analyzed daily. In salt shock loading, COD removal efficiency decreased but system returned to steady state conditions within 3 days. Similarly COD removal efficiency decreased and system recovered itself in 3 days in 5 mg/L Cr6+ shock loading, but it took much time to return steady state conditions in 10 mg/L Cr6+ shock loading. In 10 mg/L Cr6+ shock loading, COD removal efficiency decreased and system recovered itself in 5 days. In both shock loadings there were no pronounced differences on MLSS and SVI profiles

Keywords

• Wastewater treatment, shock loading, salt (NaCl), toxic (Cr6+), SBR.

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