Akademik Veri Yönetim Sistemi
Tezin Türü: Doktora
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Çevre Mühendisliği Bölümü, Türkiye
Tezin Onay Tarihi: 2005
Tezin Dili: İngilizce
Öğrenci: Tuba Hande Ergüder
Danışman: GÖKSEL NİYAZİ DEMİRER
Özet:This study was carried out to develop combined cultures which were composed of anaerobic and aerobic cultures, and could survive and operate under alternating aerobic and/or microaerobic / anaerobic conditions in semi-continuous and Upflow Sludge Blanket (USB) reactors. Granular combined cultures with median diameter of 1.28-1.86 mm and 0.8 mm were developed from suspended anaerobic and aerobic cultures in semi-continuous and USB reactors, respectively. Significant specific methanogenic activity (SMA, 14-42 mL CH4/g VSS.hr) and specific oxygen uptake rate (SOUR, 6-47 mg DO/g VSS.hr) values of combined granules in semi-continuous reactors were comparable to those of anaerobic and aerobic granules. Similarly, combined granules in USB reactors exhibited noteworthy SMA and SOUR values of 11-77 mL CH4/g VSS.hr and 10-75 mg DO/g VSS.hr, respectively. Combined granules developed in semi-continuous reactors were found to overcome the drawbacks of both anaerobic and aerobic granules such as the need for long start-up and low stability, respectively. Combined cultures were also developed from anaerobic granular and suspended aerobic cultures in three USB reactors aerated at 10 mL air/min for 4 hours/day (R2), every other day (R3) and 24 hours/day (R4). The use of combined cultures was found to be advantageous compared to the anaerobic granules for the treatment of low strength wastewaters. During municipal wastewater treatment at influent 5-day biochemical oxygen demand (BOD5) concentration of 53-118 mg/L (Hydraulic retention time, HRT: 0.75 day), combined cultures in R2, R3 and R4 exhibited average BOD5 removal efficiencies of 52, 75 and 76%, respectively. Combined granules developed in USB reactor also displayed significant BOD5 removal efficiencies (66-68%) during municipal wastewater application (HRT: 0.75 day). Combined cultures/granules developed in USB reactors might be proposed as an alternative for municipal wastewater treatment due to their advantages such as achievement of required discharge standards, prevention of biomass loss / settleability problems unlike activated sludge systems and possible methanogenic activity as well as high settling characteristics comparable to those of anaerobic granules.